Viewing: service.c
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved.
* Use is subject to license terms.
*
* Copyright (c) 2010, 2017, Intel Corporation.
*/
/*
* This file is part of Lustre, http://www.lustre.org/
*/
#define DEBUG_SUBSYSTEM S_RPC
#include <linux/delay.h>
#include <linux/fs_struct.h>
#include <linux/kthread.h>
#include <linux/ratelimit.h>
#include <lustre_compat/linux/timer.h>
#include <obd_support.h>
#include <obd_class.h>
#include <lustre_net.h>
#include <lu_object.h>
#include <uapi/linux/lnet/lnet-types.h>
#include "ptlrpc_internal.h"
/* The following are visible and mutable through /sys/module/ptlrpc */
int test_req_buffer_pressure = 0;
module_param(test_req_buffer_pressure, int, 0444);
MODULE_PARM_DESC(test_req_buffer_pressure, "set non-zero to put pressure on request buffer pools");
module_param(at_min, int, 0644);
MODULE_PARM_DESC(at_min, "Adaptive timeout minimum (sec)");
module_param(at_max, int, 0644);
MODULE_PARM_DESC(at_max, "Adaptive timeout maximum (sec)");
module_param(at_history, int, 0644);
MODULE_PARM_DESC(at_history,
"Adaptive timeouts remember the slowest event that took place within this period (sec)");
module_param(at_unhealthy_factor, int, 0644);
MODULE_PARM_DESC(at_unhealthy_factor,
"Multiple of at_max when delayed RPCs considered unhealthy");
module_param(at_early_margin, int, 0644);
MODULE_PARM_DESC(at_early_margin, "How soon before an RPC deadline to send an early reply");
module_param(at_extra, int, 0644);
MODULE_PARM_DESC(at_extra, "How much extra time to give with each early reply");
/* forward ref */
static int ptlrpc_server_post_idle_rqbds(struct ptlrpc_service_part *svcpt);
static void ptlrpc_server_hpreq_fini(struct ptlrpc_request *req);
static void ptlrpc_at_remove_timed(struct ptlrpc_request *req);
static int ptlrpc_start_threads(struct ptlrpc_service *svc);
static int ptlrpc_start_thread(struct ptlrpc_service_part *svcpt, int wait);
/* Holds a list of all PTLRPC services */
LIST_HEAD(ptlrpc_all_services);
/* Used to protect the @ptlrpc_all_services list */
struct mutex ptlrpc_all_services_mutex;
static struct ptlrpc_request_buffer_desc *
ptlrpc_alloc_rqbd(struct ptlrpc_service_part *svcpt)
{
struct ptlrpc_service *svc = svcpt->scp_service;
struct ptlrpc_request_buffer_desc *rqbd;
OBD_CPT_ALLOC_PTR(rqbd, svc->srv_cptable, svcpt->scp_cpt);
if (rqbd == NULL)
return NULL;
rqbd->rqbd_svcpt = svcpt;
rqbd->rqbd_refcount = 0;
rqbd->rqbd_cbid.cbid_fn = request_in_callback;
rqbd->rqbd_cbid.cbid_arg = rqbd;
INIT_LIST_HEAD(&rqbd->rqbd_reqs);
OBD_CPT_ALLOC_LARGE(rqbd->rqbd_buffer, svc->srv_cptable,
svcpt->scp_cpt, svc->srv_buf_size);
if (rqbd->rqbd_buffer == NULL) {
OBD_FREE_PTR(rqbd);
return NULL;
}
spin_lock(&svcpt->scp_lock);
list_add(&rqbd->rqbd_list, &svcpt->scp_rqbd_idle);
svcpt->scp_nrqbds_total++;
spin_unlock(&svcpt->scp_lock);
return rqbd;
}
static void ptlrpc_free_rqbd(struct ptlrpc_request_buffer_desc *rqbd)
{
struct ptlrpc_service_part *svcpt = rqbd->rqbd_svcpt;
LASSERT(rqbd->rqbd_refcount == 0);
LASSERT(list_empty(&rqbd->rqbd_reqs));
OBD_FREE_LARGE(rqbd->rqbd_buffer, svcpt->scp_service->srv_buf_size);
OBD_FREE_PTR(rqbd);
}
static int ptlrpc_grow_req_bufs(struct ptlrpc_service_part *svcpt, int post)
{
struct ptlrpc_service *svc = svcpt->scp_service;
struct ptlrpc_request_buffer_desc *rqbd;
int rc = 0;
int i;
if (svcpt->scp_rqbd_allocating)
goto try_post;
spin_lock(&svcpt->scp_lock);
/* check again with lock */
if (svcpt->scp_rqbd_allocating) {
/* NB: we might allow more than one thread in the future */
LASSERT(svcpt->scp_rqbd_allocating == 1);
spin_unlock(&svcpt->scp_lock);
goto try_post;
}
svcpt->scp_rqbd_allocating++;
spin_unlock(&svcpt->scp_lock);
for (i = 0; i < svc->srv_nbuf_per_group; i++) {
/*
* NB: another thread might have recycled enough rqbds, we
* need to make sure it wouldn't over-allocate, see LU-1212.
*/
if (svcpt->scp_nrqbds_posted >= svc->srv_nbuf_per_group ||
(svc->srv_nrqbds_max != 0 &&
svcpt->scp_nrqbds_total > svc->srv_nrqbds_max))
break;
rqbd = ptlrpc_alloc_rqbd(svcpt);
if (rqbd == NULL) {
CERROR("%s: Can't allocate request buffer\n",
svc->srv_name);
rc = -ENOMEM;
break;
}
}
spin_lock(&svcpt->scp_lock);
LASSERT(svcpt->scp_rqbd_allocating == 1);
svcpt->scp_rqbd_allocating--;
spin_unlock(&svcpt->scp_lock);
CDEBUG(D_RPCTRACE,
"%s: allocate %d new %d-byte reqbufs (%d/%d left), rc = %d\n",
svc->srv_name, i, svc->srv_buf_size, svcpt->scp_nrqbds_posted,
svcpt->scp_nrqbds_total, rc);
try_post:
if (post && rc == 0)
rc = ptlrpc_server_post_idle_rqbds(svcpt);
return rc;
}
/**
* ptlrpc_save_lock() - Part of Rep-Ack(Reply Acknowledgement) logic
* @req: pointer to struct ptlrpc_request
* @lock: pointer to lustre_handle (to be saved)
* @no_ack: if True, server will not wait for client ack. (incl difficult reqs)
*
* Puts(saves) a lock and its mode into reply state assotiated to request reply
*/
void ptlrpc_save_lock(struct ptlrpc_request *req, struct lustre_handle *lock,
bool no_ack)
{
struct ptlrpc_reply_state *rs = req->rq_reply_state;
int idx;
LASSERT(rs != NULL);
CDEBUG(D_RPCTRACE, "nlocks %d\n", rs->rs_nlocks);
LASSERT(rs->rs_nlocks < RS_MAX_LOCKS);
idx = rs->rs_nlocks++;
rs->rs_locks[idx] = *lock;
rs->rs_difficult = 1;
rs->rs_no_ack = no_ack;
}
EXPORT_SYMBOL(ptlrpc_save_lock);
struct ptlrpc_hr_partition;
struct ptlrpc_hr_thread {
int hrt_id; /* thread ID */
spinlock_t hrt_lock;
wait_queue_head_t hrt_waitq;
struct list_head hrt_queue;
struct ptlrpc_hr_partition *hrt_partition;
};
struct ptlrpc_hr_partition {
/* # of started threads */
atomic_t hrp_nstarted;
/* # of stopped threads */
atomic_t hrp_nstopped;
/* cpu partition id */
int hrp_cpt;
/* round-robin rotor for choosing thread */
int hrp_rotor;
/* total number of threads on this partition */
int hrp_nthrs;
/* threads table */
struct ptlrpc_hr_thread *hrp_thrs;
};
struct ptlrpc_hr_service {
/* CPU partition table, it's just cfs_cpt_tab for now */
struct cfs_cpt_table *hr_cpt_table;
/** controller sleep waitq */
wait_queue_head_t hr_waitq;
unsigned int hr_stopping;
/** roundrobin rotor for non-affinity service */
unsigned int hr_rotor;
/* partition data */
struct ptlrpc_hr_partition **hr_partitions;
};
struct rs_batch {
struct list_head rsb_replies;
unsigned int rsb_n_replies;
struct ptlrpc_service_part *rsb_svcpt;
};
/** reply handling service. */
static struct ptlrpc_hr_service ptlrpc_hr;
/* maximum mumber of replies scheduled in one batch */
#define MAX_SCHEDULED 256
/* Initialize a reply batch. */
static void rs_batch_init(struct rs_batch *b)
{
memset(b, 0, sizeof(*b));
INIT_LIST_HEAD(&b->rsb_replies);
}
/* Choose an hr thread to dispatch requests to. */
static
struct ptlrpc_hr_thread *ptlrpc_hr_select(struct ptlrpc_service_part *svcpt)
{
struct ptlrpc_hr_partition *hrp;
unsigned int rotor;
if (svcpt->scp_cpt >= 0 &&
svcpt->scp_service->srv_cptable == ptlrpc_hr.hr_cpt_table) {
/* directly match partition */
hrp = ptlrpc_hr.hr_partitions[svcpt->scp_cpt];
} else {
rotor = ptlrpc_hr.hr_rotor++;
rotor %= cfs_cpt_number(ptlrpc_hr.hr_cpt_table);
hrp = ptlrpc_hr.hr_partitions[rotor];
}
rotor = hrp->hrp_rotor++;
return &hrp->hrp_thrs[rotor % hrp->hrp_nthrs];
}
/* Dispatch all replies accumulated in the batch to one from
* dedicated reply handling threads.
*/
static void rs_batch_dispatch(struct rs_batch *b)
{
if (b->rsb_n_replies != 0) {
struct ptlrpc_hr_thread *hrt;
hrt = ptlrpc_hr_select(b->rsb_svcpt);
spin_lock(&hrt->hrt_lock);
list_splice_init(&b->rsb_replies, &hrt->hrt_queue);
spin_unlock(&hrt->hrt_lock);
wake_up(&hrt->hrt_waitq);
b->rsb_n_replies = 0;
}
}
/**
* rs_batch_add() - Add a reply to a batch.
* @b: pointer to struct rs_batch where @rs will be added
* @rs: pointer to ptlrpc_reply_state to be added to @b
*
* Add one reply object to a batch, schedule batched replies if overload.
*/
static void rs_batch_add(struct rs_batch *b, struct ptlrpc_reply_state *rs)
{
struct ptlrpc_service_part *svcpt = rs->rs_svcpt;
if (svcpt != b->rsb_svcpt || b->rsb_n_replies >= MAX_SCHEDULED) {
if (b->rsb_svcpt != NULL) {
rs_batch_dispatch(b);
spin_unlock(&b->rsb_svcpt->scp_rep_lock);
}
spin_lock(&svcpt->scp_rep_lock);
b->rsb_svcpt = svcpt;
}
spin_lock(&rs->rs_lock);
rs->rs_scheduled_ever = 1;
if (rs->rs_scheduled == 0) {
list_move(&rs->rs_list, &b->rsb_replies);
rs->rs_scheduled = 1;
b->rsb_n_replies++;
}
rs->rs_committed = 1;
spin_unlock(&rs->rs_lock);
}
/* Reply batch finalization. Dispatch remaining replies from the batch
* and release remaining spinlock.
*/
static void rs_batch_fini(struct rs_batch *b)
{
if (b->rsb_svcpt != NULL) {
rs_batch_dispatch(b);
spin_unlock(&b->rsb_svcpt->scp_rep_lock);
}
}
#define DECLARE_RS_BATCH(b) struct rs_batch b
/* Put reply state into a queue for processing because we received
* ACK from the client
*/
void ptlrpc_dispatch_difficult_reply(struct ptlrpc_reply_state *rs)
{
struct ptlrpc_hr_thread *hrt;
ENTRY;
LASSERT(list_empty(&rs->rs_list));
hrt = ptlrpc_hr_select(rs->rs_svcpt);
spin_lock(&hrt->hrt_lock);
list_add_tail(&rs->rs_list, &hrt->hrt_queue);
spin_unlock(&hrt->hrt_lock);
wake_up(&hrt->hrt_waitq);
EXIT;
}
void ptlrpc_schedule_difficult_reply(struct ptlrpc_reply_state *rs)
{
ENTRY;
assert_spin_locked(&rs->rs_svcpt->scp_rep_lock);
assert_spin_locked(&rs->rs_lock);
LASSERT(rs->rs_difficult);
rs->rs_scheduled_ever = 1; /* flag any notification attempt */
if (rs->rs_scheduled) { /* being set up or already notified */
EXIT;
return;
}
rs->rs_scheduled = 1;
list_del_init(&rs->rs_list);
ptlrpc_dispatch_difficult_reply(rs);
EXIT;
}
EXPORT_SYMBOL(ptlrpc_schedule_difficult_reply);
void ptlrpc_commit_replies(struct obd_export *exp)
{
struct ptlrpc_reply_state *rs, *nxt;
DECLARE_RS_BATCH(batch);
ENTRY;
rs_batch_init(&batch);
/*
* Find any replies that have been committed and get their service
* to attend to complete them.
*/
/* CAVEAT EMPTOR: spinlock ordering!!! */
spin_lock(&exp->exp_uncommitted_replies_lock);
list_for_each_entry_safe(rs, nxt, &exp->exp_uncommitted_replies,
rs_obd_list) {
LASSERT(rs->rs_difficult);
/* VBR: per-export last_committed */
LASSERT(rs->rs_export);
if (rs->rs_transno <= exp->exp_last_committed) {
list_del_init(&rs->rs_obd_list);
rs_batch_add(&batch, rs);
}
}
spin_unlock(&exp->exp_uncommitted_replies_lock);
rs_batch_fini(&batch);
EXIT;
}
static int ptlrpc_server_post_idle_rqbds(struct ptlrpc_service_part *svcpt)
{
struct ptlrpc_request_buffer_desc *rqbd;
int rc;
int posted = 0;
for (;;) {
spin_lock(&svcpt->scp_lock);
if (list_empty(&svcpt->scp_rqbd_idle)) {
spin_unlock(&svcpt->scp_lock);
return posted;
}
rqbd = list_first_entry(&svcpt->scp_rqbd_idle,
struct ptlrpc_request_buffer_desc,
rqbd_list);
/* assume we will post successfully */
svcpt->scp_nrqbds_posted++;
list_move(&rqbd->rqbd_list, &svcpt->scp_rqbd_posted);
spin_unlock(&svcpt->scp_lock);
rc = ptlrpc_register_rqbd(rqbd);
if (rc != 0)
break;
posted = 1;
}
spin_lock(&svcpt->scp_lock);
svcpt->scp_nrqbds_posted--;
list_move_tail(&rqbd->rqbd_list, &svcpt->scp_rqbd_idle);
/*
* Don't complain if no request buffers are posted right now; LNET
* won't drop requests because we set the portal lazy!
*/
spin_unlock(&svcpt->scp_lock);
return -1;
}
static void ptlrpc_at_timer(cfs_timer_cb_arg_t data)
{
struct ptlrpc_service_part *svcpt;
svcpt = cfs_from_timer(svcpt, data, scp_at_timer);
svcpt->scp_at_check = 1;
svcpt->scp_at_checktime = ktime_get();
wake_up(&svcpt->scp_waitq);
}
static void ptlrpc_server_nthreads_check(struct ptlrpc_service *svc,
struct ptlrpc_service_conf *conf)
{
struct ptlrpc_service_thr_conf *tc = &conf->psc_thr;
unsigned int init;
unsigned int total;
unsigned int nthrs;
int weight;
/*
* Common code for estimating & validating threads number.
* CPT affinity service could have percpt thread-pool instead
* of a global thread-pool, which means user might not always
* get the threads number they give it in conf::tc_nthrs_user
* even they did set. It's because we need to validate threads
* number for each CPT to guarantee each pool will have enough
* threads to keep the service healthy.
*/
init = PTLRPC_NTHRS_INIT + (svc->srv_ops.so_hpreq_handler != NULL);
init = max_t(int, init, tc->tc_nthrs_init);
/*
* NB: please see comments in lustre_lnet.h for definition
* details of these members
*/
LASSERT(tc->tc_nthrs_max != 0);
if (tc->tc_nthrs_user != 0) {
/*
* In case there is a reason to test a service with many
* threads, we give a less strict check here, it can
* be up to 8 * nthrs_max
*/
total = min(tc->tc_nthrs_max * 8, tc->tc_nthrs_user);
nthrs = total / svc->srv_ncpts;
init = max(init, nthrs);
goto out;
}
total = tc->tc_nthrs_max;
if (tc->tc_nthrs_base == 0) {
/*
* don't care about base threads number per partition,
* this is most for non-affinity service
*/
nthrs = total / svc->srv_ncpts;
goto out;
}
nthrs = tc->tc_nthrs_base;
if (svc->srv_ncpts == 1) {
int i;
/*
* NB: Increase the base number if it's single partition
* and total number of cores/HTs is larger or equal to 4.
* result will always < 2 * nthrs_base
*/
weight = cfs_cpt_weight(svc->srv_cptable, CFS_CPT_ANY);
for (i = 1; (weight >> (i + 1)) != 0 && /* >= 4 cores/HTs */
(tc->tc_nthrs_base >> i) != 0; i++)
nthrs += tc->tc_nthrs_base >> i;
}
if (tc->tc_thr_factor != 0) {
int factor = tc->tc_thr_factor;
const int fade = 4;
/*
* User wants to increase number of threads with for
* each CPU core/HT, most likely the factor is larger than
* one thread/core because service threads are supposed to
* be blocked by lock or wait for IO.
*/
/*
* Amdahl's law says that adding processors wouldn't give
* a linear increasing of parallelism, so it's nonsense to
* have too many threads no matter how many cores/HTs
* there are.
*/
preempt_disable();
if (cpumask_weight
(topology_sibling_cpumask(smp_processor_id())) > 1) {
/* weight is # of HTs */
/* depress thread factor for hyper-thread */
factor = factor - (factor >> 1) + (factor >> 3);
}
preempt_enable();
weight = cfs_cpt_weight(svc->srv_cptable, 0);
for (; factor > 0 && weight > 0; factor--, weight -= fade)
nthrs += min(weight, fade) * factor;
}
if (nthrs * svc->srv_ncpts > tc->tc_nthrs_max) {
nthrs = max(tc->tc_nthrs_base,
tc->tc_nthrs_max / svc->srv_ncpts);
}
out:
nthrs = max(nthrs, tc->tc_nthrs_init);
svc->srv_nthrs_cpt_limit = nthrs;
svc->srv_nthrs_cpt_init = init;
if (nthrs * svc->srv_ncpts > tc->tc_nthrs_max) {
CDEBUG(D_OTHER,
"%s: This service may have more threads (%d) than the given soft limit (%d)\n",
svc->srv_name, nthrs * svc->srv_ncpts,
tc->tc_nthrs_max);
}
}
/**
* ptlrpc_service_part_init() - Initialize percpt data for a service
* @svc: pointer to ptlrpc_service struct
* @svcpt: pltrpc_service_part which is to get intialize
* @cpt: CPU ID @svcpt will be tied to
*
* Returns:
* * %0 on success
* * %negative on failure
*/
static int ptlrpc_service_part_init(struct ptlrpc_service *svc,
struct ptlrpc_service_part *svcpt, int cpt)
{
struct ptlrpc_at_array *array;
int size;
int index;
int rc;
svcpt->scp_cpt = cpt;
INIT_LIST_HEAD(&svcpt->scp_threads);
/* rqbd and incoming request queue */
spin_lock_init(&svcpt->scp_lock);
mutex_init(&svcpt->scp_mutex);
INIT_LIST_HEAD(&svcpt->scp_rqbd_idle);
INIT_LIST_HEAD(&svcpt->scp_rqbd_posted);
INIT_LIST_HEAD(&svcpt->scp_req_incoming);
init_waitqueue_head(&svcpt->scp_waitq);
/* history request & rqbd list */
INIT_LIST_HEAD(&svcpt->scp_hist_reqs);
INIT_LIST_HEAD(&svcpt->scp_hist_rqbds);
/* acitve requests and hp requests */
spin_lock_init(&svcpt->scp_req_lock);
/* reply states */
spin_lock_init(&svcpt->scp_rep_lock);
INIT_LIST_HEAD(&svcpt->scp_rep_active);
INIT_LIST_HEAD(&svcpt->scp_rep_idle);
init_waitqueue_head(&svcpt->scp_rep_waitq);
atomic_set(&svcpt->scp_nreps_difficult, 0);
/* adaptive timeout */
spin_lock_init(&svcpt->scp_at_lock);
array = &svcpt->scp_at_array;
size = at_est2timeout(obd_get_at_max(NULL));
array->paa_size = size;
array->paa_count = 0;
array->paa_deadline = -1;
/* allocate memory for scp_at_array (ptlrpc_at_array) */
OBD_CPT_ALLOC(array->paa_reqs_array,
svc->srv_cptable, cpt, sizeof(struct list_head) * size);
if (array->paa_reqs_array == NULL)
return -ENOMEM;
for (index = 0; index < size; index++)
INIT_LIST_HEAD(&array->paa_reqs_array[index]);
OBD_CPT_ALLOC(array->paa_reqs_count,
svc->srv_cptable, cpt, sizeof(__u32) * size);
if (array->paa_reqs_count == NULL)
goto failed;
cfs_timer_setup(&svcpt->scp_at_timer, ptlrpc_at_timer,
(unsigned long)svcpt, 0);
/*
* At SOW, service time should be quick; 10s seems generous. If client
* timeout is less than this, we'll be sending an early reply.
*/
at_init(&svcpt->scp_at_estimate, 10, 0);
/* assign this before call ptlrpc_grow_req_bufs */
svcpt->scp_service = svc;
/* Now allocate the request buffers, but don't post them now */
rc = ptlrpc_grow_req_bufs(svcpt, 0);
/*
* We shouldn't be under memory pressure at startup, so
* fail if we can't allocate all our buffers at this time.
*/
if (rc != 0)
goto failed;
return 0;
failed:
if (array->paa_reqs_count != NULL) {
OBD_FREE_PTR_ARRAY(array->paa_reqs_count, size);
array->paa_reqs_count = NULL;
}
if (array->paa_reqs_array != NULL) {
OBD_FREE_PTR_ARRAY(array->paa_reqs_array, array->paa_size);
array->paa_reqs_array = NULL;
}
return -ENOMEM;
}
/**
* ptlrpc_register_service() - Initialize service on a given portal (LNET)
* @conf: pointer to ptlrpc_service_conf (configuration)
* @parent: Parent directory under sysfs
* @debugfs_entry: Parent directoy under debugfs
*
* This includes starting serving threads, allocating and posting rqbds and
* so on.
*
* Return pointer to ptlrpc_service on Success else ERR_PTR on failure
*/
struct ptlrpc_service *ptlrpc_register_service(struct ptlrpc_service_conf *conf,
struct kset *parent,
struct dentry *debugfs_entry)
{
struct ptlrpc_service_cpt_conf *cconf = &conf->psc_cpt;
struct ptlrpc_service *service;
struct ptlrpc_service_part *svcpt;
struct cfs_cpt_table *cptable;
char param[MAX_OBD_NAME * 4];
u32 *cpts = NULL;
int ncpts;
int cpt;
int rc;
int i;
ENTRY;
LASSERT(conf->psc_buf.bc_nbufs > 0);
LASSERT(conf->psc_buf.bc_buf_size >=
conf->psc_buf.bc_req_max_size + SPTLRPC_MAX_PAYLOAD);
LASSERT(conf->psc_thr.tc_ctx_tags != 0);
cptable = cconf->cc_cptable;
if (cptable == NULL)
cptable = cfs_cpt_tab;
if (conf->psc_thr.tc_cpu_bind > 1) {
CERROR("%s: Invalid cpu bind value %d, only 1 or 0 allowed\n",
conf->psc_name, conf->psc_thr.tc_cpu_bind);
RETURN(ERR_PTR(-EINVAL));
}
if (!cconf->cc_affinity) {
ncpts = 1;
} else {
ncpts = cfs_cpt_number(cptable);
if (cconf->cc_pattern != NULL) {
struct cfs_expr_list *el;
rc = cfs_expr_list_parse(cconf->cc_pattern,
strlen(cconf->cc_pattern),
0, ncpts - 1, &el);
if (rc != 0) {
CERROR("%s: invalid CPT pattern string: %s\n",
conf->psc_name, cconf->cc_pattern);
RETURN(ERR_PTR(-EINVAL));
}
rc = cfs_expr_list_values(el, ncpts, &cpts);
cfs_expr_list_free(el);
if (rc <= 0) {
CERROR("%s: failed to parse CPT array %s: %d\n",
conf->psc_name, cconf->cc_pattern, rc);
RETURN(ERR_PTR(rc < 0 ? rc : -EINVAL));
}
ncpts = rc;
}
}
OBD_ALLOC(service, offsetof(struct ptlrpc_service, srv_parts[ncpts]));
if (service == NULL) {
if (cpts != NULL)
cfs_expr_list_values_free(cpts, ncpts);
RETURN(ERR_PTR(-ENOMEM));
}
service->srv_cptable = cptable;
service->srv_cpts = cpts;
service->srv_ncpts = ncpts;
service->srv_cpt_bind = conf->psc_thr.tc_cpu_bind;
service->srv_cpt_bits = 0; /* it's zero already, easy to read... */
while ((1 << service->srv_cpt_bits) < cfs_cpt_number(cptable))
service->srv_cpt_bits++;
/* public members */
spin_lock_init(&service->srv_lock);
service->srv_name = conf->psc_name;
service->srv_watchdog_factor = conf->psc_watchdog_factor;
INIT_LIST_HEAD(&service->srv_list); /* for safty of cleanup */
/* buffer configuration */
service->srv_nbuf_per_group = test_req_buffer_pressure ?
1 : conf->psc_buf.bc_nbufs;
/* do not limit max number of rqbds by default */
service->srv_nrqbds_max = 0;
service->srv_max_req_size = conf->psc_buf.bc_req_max_size +
SPTLRPC_MAX_PAYLOAD;
service->srv_buf_size = conf->psc_buf.bc_buf_size;
service->srv_rep_portal = conf->psc_buf.bc_rep_portal;
service->srv_req_portal = conf->psc_buf.bc_req_portal;
/* With slab/alloc_pages buffer size will be rounded up to 2^n */
if (service->srv_buf_size & (service->srv_buf_size - 1)) {
int round = size_roundup_power2(service->srv_buf_size);
service->srv_buf_size = round;
}
/* Increase max reply size to next power of two */
service->srv_max_reply_size = 1;
while (service->srv_max_reply_size <
conf->psc_buf.bc_rep_max_size + SPTLRPC_MAX_PAYLOAD)
service->srv_max_reply_size <<= 1;
service->srv_thread_name = conf->psc_thr.tc_thr_name;
service->srv_ctx_tags = conf->psc_thr.tc_ctx_tags;
service->srv_hpreq_ratio = PTLRPC_SVC_HP_RATIO;
service->srv_ops = conf->psc_ops;
for (i = 0; i < ncpts; i++) {
if (!cconf->cc_affinity)
cpt = CFS_CPT_ANY;
else
cpt = cpts != NULL ? cpts[i] : i;
OBD_CPT_ALLOC(svcpt, cptable, cpt, sizeof(*svcpt));
if (svcpt == NULL)
GOTO(failed, rc = -ENOMEM);
service->srv_parts[i] = svcpt;
rc = ptlrpc_service_part_init(service, svcpt, cpt);
if (rc != 0)
GOTO(failed, rc);
}
ptlrpc_server_nthreads_check(service, conf);
rc = LNetSetLazyPortal(service->srv_req_portal);
LASSERT(rc == 0);
mutex_lock(&ptlrpc_all_services_mutex);
list_add(&service->srv_list, &ptlrpc_all_services);
mutex_unlock(&ptlrpc_all_services_mutex);
if (parent) {
char *path, *tmp;
rc = ptlrpc_sysfs_register_service(parent, service);
if (rc)
GOTO(failed, rc);
path = kobject_get_path(&parent->kobj, GFP_KERNEL);
if (path) {
tmp = path + strlen("/fs/lustre/");
scnprintf(param, sizeof(param), "%s.%s.stats",
tmp, service->srv_name);
tmp = param;
while ((tmp = strchr(tmp, '/')) != NULL)
*tmp = '.';
kfree(path);
}
}
ptlrpc_ldebugfs_register_service(debugfs_entry, param, service);
rc = ptlrpc_service_nrs_setup(service);
if (rc != 0)
GOTO(failed, rc);
CDEBUG(D_NET, "%s: Started, listening on portal %d\n",
service->srv_name, service->srv_req_portal);
rc = ptlrpc_start_threads(service);
if (rc != 0) {
CERROR("Failed to start threads for service %s: %d\n",
service->srv_name, rc);
GOTO(failed, rc);
}
RETURN(service);
failed:
ptlrpc_unregister_service(service);
RETURN(ERR_PTR(rc));
}
EXPORT_SYMBOL(ptlrpc_register_service);
/**
* ptlrpc_server_free_request() - free the request
* @req: ptlrpc request
*
* Actually free the request, must be called without holding svc_lock.
* note it's caller's responsibility to unlink req->rq_list.
*/
static void ptlrpc_server_free_request(struct ptlrpc_request *req)
{
LASSERT(atomic_read(&req->rq_refcount) == 0);
LASSERT(list_empty(&req->rq_timed_list));
/*
* DEBUG_REQ() assumes the reply state of a request with a valid
* ref will not be destroyed until that reference is dropped.
*/
ptlrpc_req_drop_rs(req);
sptlrpc_svc_ctx_decref(req);
if (req != &req->rq_rqbd->rqbd_req) {
/*
* NB request buffers use an embedded
* req if the incoming req unlinked the
* MD; this isn't one of them!
*/
ptlrpc_request_cache_free(req);
}
}
/**
* ptlrpc_server_drop_request() - drop a reference count of the request
* @req: pltrpc request
*
* drop a reference count of the request. if it reaches 0, we either
* put it into history list, or free it immediately.
*/
void ptlrpc_server_drop_request(struct ptlrpc_request *req)
{
struct ptlrpc_request_buffer_desc *rqbd = req->rq_rqbd;
struct ptlrpc_service_part *svcpt = rqbd->rqbd_svcpt;
struct ptlrpc_service *svc = svcpt->scp_service;
int refcount;
if (!atomic_dec_and_test(&req->rq_refcount))
return;
if (req->rq_session.lc_state == LCS_ENTERED) {
lu_context_exit(&req->rq_session);
lu_context_fini(&req->rq_session);
}
if (req->rq_at_linked) {
spin_lock(&svcpt->scp_at_lock);
/*
* recheck with lock, in case it's unlinked by
* ptlrpc_at_check_timed()
*/
if (likely(req->rq_at_linked))
ptlrpc_at_remove_timed(req);
spin_unlock(&svcpt->scp_at_lock);
}
LASSERT(list_empty(&req->rq_timed_list));
/* finalize request */
if (req->rq_export) {
class_export_put(req->rq_export);
req->rq_export = NULL;
}
spin_lock(&svcpt->scp_lock);
list_add(&req->rq_list, &rqbd->rqbd_reqs);
refcount = --(rqbd->rqbd_refcount);
if (refcount == 0) {
/* request buffer is now idle: add to history */
list_move_tail(&rqbd->rqbd_list, &svcpt->scp_hist_rqbds);
svcpt->scp_hist_nrqbds++;
/*
* cull some history?
* I expect only about 1 or 2 rqbds need to be recycled here
*/
while (svcpt->scp_hist_nrqbds > svc->srv_hist_nrqbds_cpt_max) {
rqbd = list_first_entry(&svcpt->scp_hist_rqbds,
struct ptlrpc_request_buffer_desc,
rqbd_list);
list_del(&rqbd->rqbd_list);
svcpt->scp_hist_nrqbds--;
/*
* remove rqbd's reqs from svc's req history while
* I've got the service lock
*/
list_for_each_entry(req, &rqbd->rqbd_reqs, rq_list) {
/* Track the highest culled req seq */
if (req->rq_history_seq >
svcpt->scp_hist_seq_culled) {
svcpt->scp_hist_seq_culled =
req->rq_history_seq;
}
list_del(&req->rq_history_list);
}
spin_unlock(&svcpt->scp_lock);
while ((req = list_first_entry_or_null(
&rqbd->rqbd_reqs,
struct ptlrpc_request, rq_list))) {
list_del(&req->rq_list);
ptlrpc_server_free_request(req);
}
spin_lock(&svcpt->scp_lock);
/*
* now all reqs including the embedded req has been
* disposed, schedule request buffer for re-use
* or free it to drain some in excess.
*/
LASSERT(atomic_read(&rqbd->rqbd_req.rq_refcount) == 0);
if (svcpt->scp_nrqbds_posted >=
svc->srv_nbuf_per_group ||
(svc->srv_nrqbds_max != 0 &&
svcpt->scp_nrqbds_total > svc->srv_nrqbds_max) ||
test_req_buffer_pressure) {
/* like in ptlrpc_free_rqbd() */
svcpt->scp_nrqbds_total--;
OBD_FREE_LARGE(rqbd->rqbd_buffer,
svc->srv_buf_size);
OBD_FREE_PTR(rqbd);
} else {
list_add_tail(&rqbd->rqbd_list,
&svcpt->scp_rqbd_idle);
}
}
spin_unlock(&svcpt->scp_lock);
} else if (req->rq_reply_state && req->rq_reply_state->rs_prealloc) {
/* If we are low on memory, we are not interested in history */
list_del(&req->rq_list);
list_del_init(&req->rq_history_list);
/* Track the highest culled req seq */
if (req->rq_history_seq > svcpt->scp_hist_seq_culled)
svcpt->scp_hist_seq_culled = req->rq_history_seq;
spin_unlock(&svcpt->scp_lock);
ptlrpc_server_free_request(req);
} else {
spin_unlock(&svcpt->scp_lock);
}
}
static void ptlrpc_add_exp_list_nolock(struct ptlrpc_request *req,
struct obd_export *export, bool hp)
{
__u16 tag = lustre_msg_get_tag(req->rq_reqmsg);
if (hp)
list_add(&req->rq_exp_list, &export->exp_hp_rpcs);
else
list_add(&req->rq_exp_list, &export->exp_reg_rpcs);
if (tag && export->exp_used_slots) {
if (test_bit(tag - 1, export->exp_used_slots) &&
!(lustre_msg_get_flags(req->rq_reqmsg) & MSG_RESENT)) {
DEBUG_REQ(D_ERROR, req, "export slot is used already");
}
set_bit(tag - 1, export->exp_used_slots);
}
}
void ptlrpc_del_exp_list(struct ptlrpc_request *req)
{
__u16 tag = 0;
if (unlikely(!req->rq_export))
return;
if (likely(req->rq_reqmsg))
tag = lustre_msg_get_tag(req->rq_reqmsg);
spin_lock(&req->rq_export->exp_rpc_lock);
list_del_init(&req->rq_exp_list);
if (tag && !req->rq_obsolete && req->rq_export->exp_used_slots)
clear_bit(tag - 1, req->rq_export->exp_used_slots);
spin_unlock(&req->rq_export->exp_rpc_lock);
}
/**
* ptlrpc_request_change_export() - Change request export
* @req: ptlrpc request export to be changed
* @export: new export @req is changed to
*
* Change request export and move hp request from old export to new
*/
void ptlrpc_request_change_export(struct ptlrpc_request *req,
struct obd_export *export)
{
if (req->rq_export != NULL) {
LASSERT(!list_empty(&req->rq_exp_list));
/* remove rq_exp_list from last export */
ptlrpc_del_exp_list(req);
/* export has one reference already, so it's safe to
* add req to export queue here and get another
* reference for request later
*/
spin_lock(&export->exp_rpc_lock);
ptlrpc_add_exp_list_nolock(req, export, req->rq_ops != NULL);
spin_unlock(&export->exp_rpc_lock);
class_export_rpc_dec(req->rq_export);
class_export_put(req->rq_export);
}
/* request takes one export refcount */
req->rq_export = class_export_get(export);
class_export_rpc_inc(export);
}
/* to finish a request: stop sending more early replies, and release
* the request.
*/
static void ptlrpc_server_finish_request(struct ptlrpc_service_part *svcpt,
struct ptlrpc_request *req)
{
ptlrpc_server_hpreq_fini(req);
ptlrpc_server_drop_request(req);
}
/* to finish an active request: stop sending more early replies, and release
* the request. should be called after we finished handling the request.
*/
static void ptlrpc_server_finish_active_request(
struct ptlrpc_service_part *svcpt,
struct ptlrpc_request *req)
{
spin_lock(&svcpt->scp_req_lock);
ptlrpc_nrs_req_stop_nolock(req);
svcpt->scp_nreqs_active--;
if (req->rq_hp)
svcpt->scp_nhreqs_active--;
spin_unlock(&svcpt->scp_req_lock);
ptlrpc_nrs_req_finalize(req);
if (req->rq_export != NULL)
class_export_rpc_dec(req->rq_export);
ptlrpc_server_finish_request(svcpt, req);
}
/**
* ptlrpc_export_timeout() - Calcuate an export eviction timeout
* @obd: export to calucalte the timout of
* @at: AT of RPC service time to calculate timeout for
* @netl: network AT
* @rpc_left_time: left service time for the current RPC 0 if not applicable
* @pinger: if the caller is ping evictor or ldlm
*
* Calculate an export eviction timeout.
* Used for both cases, lock prolong timeout and ping evictor timeout.
*
* Whereas a problem client may be still alive trying hard to reconnect and to
* resend its RPCs, we should not consider the worst ever case, consisting of
* a chain of failures on each step. Let this timeout survive a recovery of
* just 1 failure:
* - an RPC timeout;
* - a re-connect success;
*
* For lock prolong timeout, we are in the middle of the process -
* BL AST is sent, CANCEL is ahead - it is still 1 reply for the current RPC
* and at least 1 another RPC (which will trigger another refresh if it will be
* not CANCEL) - but more accurate than ldlm_bl_timeout as the timeout is taken
* from the RPC (i.e. the view of the client on the current AT) is taken into
* account.
*
* Return timeout in seconds to wait for the next client's RPC
*/
static timeout_t ptlrpc_export_timeout(struct obd_device *obd,
struct adaptive_timeout *at,
timeout_t netl,
timeout_t rpc_left_time,
bool pinger)
{
timeout_t timeout, at_timeout, req_timeout;
if (obd_at_off(obd))
return obd_timeout / 2;
LASSERT(at != NULL);
at_timeout = at_est2timeout(obd_at_get(obd, at)) + netl;
if (pinger) {
/* There might be a delay till the next RPC. In fact it is two
* PING_INTERVALs due to ptlrpc_pinger_main logic.
* In addition, the ping itself may time out, but no resend will
* be needed, export is updated on re-connect */
timeout = 2 * PING_INTERVAL + at_timeout;
} else {
/* For the lock prolong, we have an RPC in hand, which may still
* get its reply lost. Thus, it may be either this one or the
* next client's RPC times out, take the max.
* Considering the current RPC, take just the left time. */
req_timeout = max(rpc_left_time + (netl >> 1), at_timeout);
/* Adding the RPC resend time */
timeout = req_timeout + at_timeout;
}
/* Adding the re-connect time */
timeout += INITIAL_CONNECT_TIMEOUT + netl;
/* Let's be a bit more conservative than client */
return max(timeout + (timeout >> 4),
(timeout_t)obd_get_ldlm_enqueue_min(obd));
}
/**
* ptlrpc_export_prolong_timeout() - Used for lock prolog timeout
* @req: ptlrpc request
* @recovery: True if this is recovery
*
* Used for lock prolog timeout, calculates a timeout for CANCEL to come.
* Also used for recovery, calculates a timeout for a next recovery RPC to come.
* In this case, there is an RPC, in hand. Thus, a particular svcpt AT is used.
*
* The reverse import network AT is used as an estimate for the client side one.
*
* Returns timeout value (seconds)
*/
timeout_t ptlrpc_export_prolong_timeout(struct ptlrpc_request *req,
bool recovery)
{
timeout_t netl;
if (recovery)
netl = lustre_msg_get_service_timeout(req->rq_reqmsg);
else
netl = obd_at_get(req->rq_export->exp_obd,
&req->rq_export->exp_imp_reverse->
imp_at.iat_net_latency);
return ptlrpc_export_timeout(req->rq_export->exp_obd,
&req->rq_rqbd->rqbd_svcpt->scp_at_estimate,
netl, req->rq_deadline -
ktime_get_real_seconds(), false);
}
/*
* Used for ping evictor, calculates a timeout for any next RPC to come.
* As there are different portals and the AT stats is separated for them,
* just the last RPC AT is used here.
*
* The reverse import network AT is used as an estimate for the client side one.
*/
static timeout_t ptlrpc_export_pinger_timeout(struct ptlrpc_request *req)
{
struct obd_import *revimp = req->rq_export->exp_imp_reverse;
timeout_t netl = obd_at_get(req->rq_export->exp_obd,
&revimp->imp_at.iat_net_latency);
return ptlrpc_export_timeout(req->rq_export->exp_obd,
&req->rq_rqbd->rqbd_svcpt->scp_at_estimate,
netl, 0, true);
}
/*
* In this case the net was down and just came back, when the 1st timeout has
* been already expired, clients just keep sending re-connects, switching
* between different connections, thus what is to be covered:
* - a previous reconnect to not yet recovered network, times out;
* - the second reconnect to the failover pair, ENODEV;
* - the third reconnect succeeds;
*/
static timeout_t ptlrpc_export_extra_timeout(struct obd_export *exp)
{
timeout_t netl, tout;
/* As this is not the 1st re-connection failure, the client might
* have net latency get extended to the max - CONNECTION_SWITCH_MAX */
netl = obd_at_get(exp->exp_obd,
&exp->exp_imp_reverse->imp_at.iat_net_latency);
tout = 3 * (INITIAL_CONNECT_TIMEOUT +
max((timeout_t)CONNECTION_SWITCH_MAX, netl));
/* Let's be a bit more conservative than client */
return tout + (tout >> 4);
}
/*
* This function makes sure dead exports are evicted in a timely manner.
* This function is only called when some export receives a message (i.e.,
* the network is up.)
*/
void ptlrpc_update_export_timer(struct ptlrpc_request *req)
{
struct obd_export *oldest_exp, *newest_exp, *exp;
time64_t current_time, timeout;
bool evict = false;
void *data;
int rc;
ENTRY;
LASSERT(req != NULL);
LASSERT(req->rq_export != NULL);
exp = req->rq_export;
current_time = ktime_get_real_seconds();
rc = obd_export_timed_init(exp, &data);
if (rc)
/* will be updated next time */
RETURN_EXIT;
/*
* exports may get disconnected from the chain even though the
* export has references, so we must keep the spin lock while
* manipulating the lists
*/
spin_lock(&exp->exp_obd->obd_dev_lock);
if (list_empty(&exp->exp_timed_chain)) {
/* this one is not timed */
spin_unlock(&exp->exp_obd->obd_dev_lock);
GOTO(err, 0);
}
exp->exp_last_request_time = current_time;
timeout = ptlrpc_export_pinger_timeout(req);
/* Do not pay attention on 1sec or smaller renewals. */
if (exp->exp_deadline + 1 >= current_time + timeout) {
spin_unlock(&exp->exp_obd->obd_dev_lock);
GOTO(err, 0);
}
newest_exp = obd_export_timed_get(exp->exp_obd, true);
obd_export_timed_del(exp);
exp->exp_deadline = current_time + timeout;
obd_export_timed_add(exp, &data);
if (test_bit(OBDF_RECOVERING, exp->exp_obd->obd_flags)) {
/* be nice to everyone during recovery */
spin_unlock(&exp->exp_obd->obd_dev_lock);
GOTO(err, 0);
}
oldest_exp = obd_export_timed_get(exp->exp_obd, false);
/* Check if the oldest entry is expired. */
if (exp->exp_obd->obd_eviction_timer == 0) {
if (current_time > oldest_exp->exp_deadline) {
timeout = newest_exp->exp_last_request_time +
((newest_exp->exp_deadline -
newest_exp->exp_last_request_time) >> 1);
if (current_time < timeout) {
/* If import is active - evict stale clients */
evict = true;
} else {
/*
* We need a second timer, in case the net was
* down and it just came back.
*/
exp->exp_obd->obd_eviction_timer =
ktime_get_real_seconds() +
ptlrpc_export_extra_timeout(oldest_exp);
CDEBUG(D_HA, "%s: Think about evicting %s "
"from %lld deadline at %lld\n",
exp->exp_obd->obd_name,
obd_export_nid2str(oldest_exp),
oldest_exp->exp_deadline,
exp->exp_obd->obd_eviction_timer);
}
}
}
spin_unlock(&exp->exp_obd->obd_dev_lock);
if (evict) {
/* Evict stale clients */
ping_evictor_wake(exp);
} else {
if (ktime_get_real_seconds() >
exp->exp_obd->obd_eviction_timer) {
/*
* The evictor won't evict anyone who we've heard from
* recently, so we don't have to check before we start
* it.
*/
if (!ping_evictor_wake(exp))
exp->exp_obd->obd_eviction_timer = 0;
}
}
EXIT;
err:
obd_export_timed_fini(exp, &data);
}
/**
* ptlrpc_check_req() - Sanity check request @req.
* @req: ptlrpc request
*
* Return 0 if all is ok, error code otherwise.
*/
static int ptlrpc_check_req(struct ptlrpc_request *req)
{
struct obd_device *obd = req->rq_export->exp_obd;
int rc = 0;
if (unlikely(lustre_msg_get_conn_cnt(req->rq_reqmsg) <
req->rq_export->exp_conn_cnt)) {
DEBUG_REQ(D_RPCTRACE, req,
"DROPPING req from old connection %d < %d",
lustre_msg_get_conn_cnt(req->rq_reqmsg),
req->rq_export->exp_conn_cnt);
return -EEXIST;
}
if (unlikely(obd == NULL || test_bit(OBDF_FAIL, obd->obd_flags))) {
/*
* Failing over, don't handle any more reqs,
* send error response instead.
*/
CDEBUG(D_RPCTRACE, "Dropping req %p for failed obd %s\n",
req, (obd != NULL) ? obd->obd_name : "unknown");
rc = -ENODEV;
} else if (lustre_msg_get_flags(req->rq_reqmsg) &
(MSG_REPLAY | MSG_REQ_REPLAY_DONE) &&
!test_bit(OBDF_RECOVERING, obd->obd_flags)) {
DEBUG_REQ(D_ERROR, req,
"Invalid replay without recovery");
class_fail_export(req->rq_export);
rc = -ENODEV;
} else if (lustre_msg_get_transno(req->rq_reqmsg) != 0 &&
!test_bit(OBDF_RECOVERING, obd->obd_flags)) {
DEBUG_REQ(D_ERROR, req,
"Invalid req with transno %llu without recovery",
lustre_msg_get_transno(req->rq_reqmsg));
class_fail_export(req->rq_export);
rc = -ENODEV;
}
if (unlikely(rc < 0)) {
req->rq_status = rc;
ptlrpc_error(req);
}
return rc;
}
static void ptlrpc_at_set_timer(struct ptlrpc_service_part *svcpt)
{
struct ptlrpc_at_array *array = &svcpt->scp_at_array;
time64_t next;
if (array->paa_count == 0) {
timer_delete(&svcpt->scp_at_timer);
return;
}
/* Set timer for closest deadline */
next = array->paa_deadline - ktime_get_real_seconds() -
at_early_margin;
if (next <= 0) {
ptlrpc_at_timer(cfs_timer_cb_arg(svcpt, scp_at_timer));
} else {
mod_timer(&svcpt->scp_at_timer,
jiffies + nsecs_to_jiffies(next * NSEC_PER_SEC));
CDEBUG(D_INFO, "armed %s at %+llds\n",
svcpt->scp_service->srv_name, next);
}
}
/* Add rpc to early reply check list */
static int ptlrpc_at_add_timed(struct ptlrpc_request *req)
{
struct ptlrpc_service_part *svcpt = req->rq_rqbd->rqbd_svcpt;
struct ptlrpc_at_array *array = &svcpt->scp_at_array;
struct ptlrpc_request *rq = NULL;
__u32 index;
struct obd_device *obd = NULL;
if (req->rq_export)
obd = req->rq_export->exp_obd;
if (obd_at_off(obd))
return(0);
if (req->rq_no_reply)
return 0;
if ((lustre_msghdr_get_flags(req->rq_reqmsg) & MSGHDR_AT_SUPPORT) == 0)
return(-ENOSYS);
spin_lock(&svcpt->scp_at_lock);
LASSERT(list_empty(&req->rq_timed_list));
div_u64_rem(req->rq_deadline, array->paa_size, &index);
if (array->paa_reqs_count[index] > 0) {
/*
* latest rpcs will have the latest deadlines in the list,
* so search backward.
*/
list_for_each_entry_reverse(rq, &array->paa_reqs_array[index],
rq_timed_list) {
if (req->rq_deadline >= rq->rq_deadline) {
list_add(&req->rq_timed_list,
&rq->rq_timed_list);
break;
}
}
}
/* Add the request at the head of the list */
if (list_empty(&req->rq_timed_list))
list_add(&req->rq_timed_list, &array->paa_reqs_array[index]);
spin_lock(&req->rq_lock);
req->rq_at_linked = 1;
spin_unlock(&req->rq_lock);
req->rq_at_index = index;
array->paa_reqs_count[index]++;
array->paa_count++;
if (array->paa_count == 1 || array->paa_deadline > req->rq_deadline) {
array->paa_deadline = req->rq_deadline;
ptlrpc_at_set_timer(svcpt);
}
spin_unlock(&svcpt->scp_at_lock);
return 0;
}
static void ptlrpc_at_remove_timed(struct ptlrpc_request *req)
{
struct ptlrpc_at_array *array;
array = &req->rq_rqbd->rqbd_svcpt->scp_at_array;
/* NB: must call with hold svcpt::scp_at_lock */
LASSERT(!list_empty(&req->rq_timed_list));
list_del_init(&req->rq_timed_list);
spin_lock(&req->rq_lock);
req->rq_at_linked = 0;
spin_unlock(&req->rq_lock);
array->paa_reqs_count[req->rq_at_index]--;
array->paa_count--;
}
/* Attempt to extend the request deadline by sending an early reply to the
* client.
*/
static int ptlrpc_at_send_early_reply(struct ptlrpc_request *req)
{
struct ptlrpc_service_part *svcpt = req->rq_rqbd->rqbd_svcpt;
struct ptlrpc_request *reqcopy;
struct lustre_msg *reqmsg;
timeout_t olddl = req->rq_deadline - ktime_get_real_seconds();
time64_t newdl;
int rc;
struct obd_device *obd = NULL;
ENTRY;
if (req->rq_export)
obd = req->rq_export->exp_obd;
if (CFS_FAIL_CHECK(OBD_FAIL_TGT_REPLAY_RECONNECT) ||
CFS_FAIL_PRECHECK(OBD_FAIL_PTLRPC_ENQ_RESEND)) {
/* don't send early reply */
RETURN(1);
}
/*
* deadline is when the client expects us to reply, margin is the
* difference between clients' and servers' expectations
*/
DEBUG_REQ(D_ADAPTTO, req,
"%ssending early reply (deadline %+ds, margin %+ds) for %d+%d",
obd_at_off(obd) ? "AT off - not " : "",
olddl, olddl - obd_at_get(obd, &svcpt->scp_at_estimate),
obd_at_get(obd, &svcpt->scp_at_estimate), at_extra);
if (obd_at_off(obd))
RETURN(0);
if (olddl < 0) {
/* below message is checked in replay-ost-single.sh test_9 */
DEBUG_REQ(D_WARNING, req,
"Already past deadline (%+ds), not sending early reply. Consider increasing at_early_margin (%d)?",
olddl, at_early_margin);
/* Return an error so we're not re-added to the timed list. */
RETURN(-ETIMEDOUT);
}
if ((lustre_msghdr_get_flags(req->rq_reqmsg) &
MSGHDR_AT_SUPPORT) == 0) {
DEBUG_REQ(D_INFO, req,
"Wanted to ask client for more time, but no AT support");
RETURN(-ENOSYS);
}
if (req->rq_export &&
lustre_msg_get_flags(req->rq_reqmsg) &
(MSG_REPLAY | MSG_REQ_REPLAY_DONE | MSG_LOCK_REPLAY_DONE)) {
struct obd_device *obd_exp = req->rq_export->exp_obd;
/*
* During recovery, we don't want to send too many early
* replies, but on the other hand we want to make sure the
* client has enough time to resend if the rpc is lost. So
* during the recovery period send at least 4 early replies,
* spacing them every at_extra if we can. at_estimate should
* always equal this fixed value during recovery.
*/
/*
* Don't account request processing time into AT history
* during recovery, it is not service time we need but
* includes also waiting time for recovering clients
*/
newdl = min_t(time64_t, at_extra,
obd_exp->obd_recovery_timeout / 4) +
ktime_get_real_seconds();
} else {
/*
* We want to extend the request deadline by at_extra seconds,
* so we set our service estimate to reflect how much time has
* passed since this request arrived plus an additional
* at_extra seconds. The client will calculate the new deadline
* based on this service estimate (plus some additional time to
* account for network latency). See ptlrpc_at_recv_early_reply
*/
obd_at_measure(obd, &svcpt->scp_at_estimate, at_extra +
ktime_get_real_seconds() -
req->rq_arrival_time.tv_sec);
newdl = req->rq_arrival_time.tv_sec +
obd_at_get(obd, &svcpt->scp_at_estimate);
}
/*
* Check to see if we've actually increased the deadline -
* we may be past adaptive_max
*/
if (req->rq_deadline >= newdl) {
DEBUG_REQ(D_WARNING, req,
"Could not add any time (%d/%lld), not sending early reply",
olddl, newdl - ktime_get_real_seconds());
RETURN(-ETIMEDOUT);
}
reqcopy = ptlrpc_request_cache_alloc(GFP_NOFS);
if (reqcopy == NULL)
RETURN(-ENOMEM);
OBD_ALLOC_LARGE(reqmsg, req->rq_reqlen);
if (!reqmsg)
GOTO(out_free, rc = -ENOMEM);
*reqcopy = *req;
spin_lock_init(&reqcopy->rq_early_free_lock);
reqcopy->rq_reply_state = NULL;
reqcopy->rq_rep_swab_mask = 0;
reqcopy->rq_pack_bulk = 0;
reqcopy->rq_pack_udesc = 0;
reqcopy->rq_packed_final = 0;
sptlrpc_svc_ctx_addref(reqcopy);
/* We only need the reqmsg for the magic */
reqcopy->rq_reqmsg = reqmsg;
memcpy(reqmsg, req->rq_reqmsg, req->rq_reqlen);
/*
* tgt_brw_read() and tgt_brw_write() may have decided not to reply.
* Without this check, we would fail the rq_no_reply assertion in
* ptlrpc_send_reply().
*/
if (reqcopy->rq_no_reply)
GOTO(out, rc = -ETIMEDOUT);
LASSERT(atomic_read(&req->rq_refcount));
/* if it is last refcount then early reply isn't needed */
if (atomic_read(&req->rq_refcount) == 1) {
DEBUG_REQ(D_ADAPTTO, reqcopy,
"Normal reply already sent, abort early reply");
GOTO(out, rc = -EINVAL);
}
/* Connection ref */
reqcopy->rq_export = class_conn2export(
lustre_msg_get_handle(reqcopy->rq_reqmsg));
if (reqcopy->rq_export == NULL)
GOTO(out, rc = -ENODEV);
INIT_LIST_HEAD(&reqcopy->rq_exp_list);
/* RPC ref */
class_export_rpc_inc(reqcopy->rq_export);
if (reqcopy->rq_export->exp_obd &&
test_bit(OBDF_FAIL, reqcopy->rq_export->exp_obd->obd_flags))
GOTO(out_put, rc = -ENODEV);
rc = lustre_pack_reply_flags(reqcopy, 1, NULL, NULL, LPRFL_EARLY_REPLY);
if (rc)
GOTO(out_put, rc);
rc = ptlrpc_send_reply(reqcopy, PTLRPC_REPLY_EARLY);
if (!rc) {
/* Adjust our own deadline to what we told the client */
req->rq_deadline = newdl;
req->rq_early_count++; /* number sent, server side */
} else {
DEBUG_REQ(D_ERROR, req, "Early reply send failed: rc = %d", rc);
}
/*
* Free the (early) reply state from lustre_pack_reply.
* (ptlrpc_send_reply takes it's own rs ref, so this is safe here)
*/
ptlrpc_req_drop_rs(reqcopy);
out_put:
class_export_rpc_dec(reqcopy->rq_export);
class_export_put(reqcopy->rq_export);
out:
sptlrpc_svc_ctx_decref(reqcopy);
OBD_FREE_LARGE(reqmsg, req->rq_reqlen);
out_free:
ptlrpc_request_cache_free(reqcopy);
RETURN(rc);
}
/*
* Send early replies to everybody expiring within at_early_margin
* asking for at_extra time
*/
static int ptlrpc_at_check_timed(struct ptlrpc_service_part *svcpt)
{
struct ptlrpc_at_array *array = &svcpt->scp_at_array;
struct ptlrpc_request *rq, *n;
LIST_HEAD(work_list);
__u32 index, count;
time64_t deadline;
time64_t now = ktime_get_real_seconds();
s64 delay_ms;
int first, counter = 0;
ENTRY;
spin_lock(&svcpt->scp_at_lock);
if (svcpt->scp_at_check == 0) {
spin_unlock(&svcpt->scp_at_lock);
RETURN(0);
}
delay_ms = ktime_ms_delta(ktime_get(), svcpt->scp_at_checktime);
svcpt->scp_at_check = 0;
if (array->paa_count == 0) {
spin_unlock(&svcpt->scp_at_lock);
RETURN(0);
}
/* The timer went off, but maybe the nearest rpc already completed. */
first = array->paa_deadline - now;
if (first > at_early_margin) {
/* We've still got plenty of time. Reset the timer. */
ptlrpc_at_set_timer(svcpt);
spin_unlock(&svcpt->scp_at_lock);
RETURN(0);
}
/*
* We're close to a timeout, and we don't know how much longer the
* server will take. Send early replies to everyone expiring soon.
*/
deadline = -1;
div_u64_rem(array->paa_deadline, array->paa_size, &index);
count = array->paa_count;
while (count > 0) {
count -= array->paa_reqs_count[index];
list_for_each_entry_safe(rq, n,
&array->paa_reqs_array[index],
rq_timed_list) {
if (rq->rq_deadline > now + at_early_margin) {
/* update the earliest deadline */
if (deadline == -1 ||
rq->rq_deadline < deadline)
deadline = rq->rq_deadline;
break;
}
/**
* ptlrpc_server_drop_request() may drop
* refcount to 0 already. Let's check this and
* don't add entry to work_list
*/
if (likely(atomic_inc_not_zero(&rq->rq_refcount))) {
ptlrpc_at_remove_timed(rq);
list_add(&rq->rq_timed_list, &work_list);
} else {
ptlrpc_at_remove_timed(rq);
}
counter++;
}
if (++index >= array->paa_size)
index = 0;
}
array->paa_deadline = deadline;
/* we have a new earliest deadline, restart the timer */
ptlrpc_at_set_timer(svcpt);
spin_unlock(&svcpt->scp_at_lock);
CDEBUG(D_ADAPTTO,
"timeout in %+ds, asking for %d secs on %d early replies\n",
first, at_extra, counter);
if (first < 0) {
/*
* We're already past request deadlines before we even get a
* chance to send early replies
*/
timeout_t atg = obd_at_get((struct obd_device *)NULL,
&svcpt->scp_at_estimate);
LCONSOLE_WARN("'%s' is processing requests too slowly, client may timeout. Late by %ds, missed %d early replies (reqs waiting=%d active=%d, at_estimate=%d, delay=%lldms)\n",
svcpt->scp_service->srv_name, -first, counter,
svcpt->scp_nreqs_incoming,
svcpt->scp_nreqs_active,
atg,
delay_ms);
}
/*
* we took additional refcount so entries can't be deleted from list, no
* locking is needed
*/
while ((rq = list_first_entry_or_null(&work_list,
struct ptlrpc_request,
rq_timed_list)) != NULL) {
list_del_init(&rq->rq_timed_list);
if (ptlrpc_at_send_early_reply(rq) == 0)
ptlrpc_at_add_timed(rq);
ptlrpc_server_drop_request(rq);
}
RETURN(1); /* return "did_something" for liblustre */
}
/*
* Check if we are already handling earlier incarnation of this request.
* Called under &req->rq_export->exp_rpc_lock locked
*/
static struct ptlrpc_request*
ptlrpc_server_check_resend_in_progress(struct ptlrpc_request *req)
{
struct ptlrpc_request *tmp = NULL;
if (!(lustre_msg_get_flags(req->rq_reqmsg) & MSG_RESENT))
return NULL;
/*
* This list should not be longer than max_requests in
* flights on the client, so it is not all that long.
* Also we only hit this codepath in case of a resent
* request which makes it even more rarely hit
*/
list_for_each_entry(tmp, &req->rq_export->exp_reg_rpcs,
rq_exp_list) {
/* Found duplicate one */
if (tmp->rq_xid == req->rq_xid)
goto found;
}
list_for_each_entry(tmp, &req->rq_export->exp_hp_rpcs,
rq_exp_list) {
/* Found duplicate one */
if (tmp->rq_xid == req->rq_xid)
goto found;
}
return NULL;
found:
return tmp;
}
#ifdef CONFIG_LUSTRE_FS_SERVER
static void ptlrpc_server_mark_obsolete(struct ptlrpc_request *req)
{
spin_lock(&req->rq_lock);
req->rq_obsolete = 1;
spin_unlock(&req->rq_lock);
}
static void
ptlrpc_server_mark_in_progress_obsolete(struct ptlrpc_request *req)
{
struct ptlrpc_request *tmp = NULL;
__u16 tag;
if (!tgt_is_increasing_xid_client(req->rq_export) ||
req->rq_export->exp_used_slots == NULL)
return;
tag = lustre_msg_get_tag(req->rq_reqmsg);
if (tag == 0)
return;
if (!test_bit(tag - 1, req->rq_export->exp_used_slots))
return;
/* This list should not be longer than max_requests in
* flights on the client, so it is not all that long.
* Also we only hit this codepath in case of a resent
* request which makes it even more rarely hit */
list_for_each_entry(tmp, &req->rq_export->exp_reg_rpcs, rq_exp_list) {
if (tag != lustre_msg_get_tag(tmp->rq_reqmsg))
continue;
if (req->rq_xid > tmp->rq_xid)
ptlrpc_server_mark_obsolete(tmp);
else if (req->rq_xid < tmp->rq_xid && !req_is_replay(req)) {
DEBUG_REQ(D_RPCTRACE, req, "stale request tag %u", tag);
DEBUG_REQ(D_RPCTRACE, tmp, "on the same slot");
ptlrpc_server_mark_obsolete(req);
}
}
list_for_each_entry(tmp, &req->rq_export->exp_hp_rpcs, rq_exp_list) {
if (tag != lustre_msg_get_tag(tmp->rq_reqmsg))
continue;
if (req->rq_xid > tmp->rq_xid)
ptlrpc_server_mark_obsolete(tmp);
else if (req->rq_xid < tmp->rq_xid && !req_is_replay(req)) {
DEBUG_REQ(D_RPCTRACE, req, "stale request tag %u", tag);
DEBUG_REQ(D_RPCTRACE, tmp, "on the same slot");
ptlrpc_server_mark_obsolete(req);
}
}
}
#endif
/**
* ptlrpc_server_hpreq_init() - Check request can be assigned with high priority
* @svcpt: the PTLRPC service partition
* @req: ptlrpc thread
*
* Return:
* * %<0 error occurred
* * %0 normal RPC request
* * %1 high priority request
*/
static int ptlrpc_server_hpreq_init(struct ptlrpc_service_part *svcpt,
struct ptlrpc_request *req)
{
int rc = 0;
ENTRY;
if (svcpt->scp_service->srv_ops.so_hpreq_handler != NULL) {
rc = svcpt->scp_service->srv_ops.so_hpreq_handler(req);
if (rc < 0)
RETURN(rc);
LASSERT(rc == 0);
}
if (req->rq_export != NULL && req->rq_ops != NULL) {
/*
* Perform request specific check. We should do this
* check before the request is added into exp_hp_rpcs
* list otherwise it may hit swab race at LU-1044.
*/
if (req->rq_ops->hpreq_check != NULL) {
rc = req->rq_ops->hpreq_check(req);
if (rc == -ESTALE) {
req->rq_status = rc;
ptlrpc_error(req);
}
/*
* can only return error,
* 0 for normal request,
* or 1 for high priority request
*/
LASSERT(rc <= 1);
}
}
RETURN(rc);
}
/* Remove the request from the export list. */
static void ptlrpc_server_hpreq_fini(struct ptlrpc_request *req)
{
ENTRY;
if (req->rq_export) {
/*
* refresh lock timeout again so that client has more
* room to send lock cancel RPC.
*/
if (req->rq_ops && req->rq_ops->hpreq_fini)
req->rq_ops->hpreq_fini(req);
ptlrpc_del_exp_list(req);
}
EXIT;
}
static int ptlrpc_hpreq_check(struct ptlrpc_request *req)
{
return 1;
}
static struct ptlrpc_hpreq_ops ptlrpc_hpreq_common = {
.hpreq_check = ptlrpc_hpreq_check,
};
/* Hi-Priority RPC check by RPC operation code. */
int ptlrpc_hpreq_handler(struct ptlrpc_request *req)
{
int opc = lustre_msg_get_opc(req->rq_reqmsg);
/*
* Check for export to let only reconnects for not yet evicted
* export to become a HP rpc.
*/
if ((req->rq_export != NULL) &&
(opc == OBD_PING || opc == MDS_CONNECT || opc == OST_CONNECT))
req->rq_ops = &ptlrpc_hpreq_common;
return 0;
}
EXPORT_SYMBOL(ptlrpc_hpreq_handler);
static int ptlrpc_server_request_add(struct ptlrpc_service_part *svcpt,
struct ptlrpc_request *req)
{
int rc;
bool hp;
struct ptlrpc_request *orig = NULL;
int opc;
ENTRY;
rc = ptlrpc_server_hpreq_init(svcpt, req);
if (rc < 0)
RETURN(rc);
hp = rc > 0;
ptlrpc_nrs_req_initialize(svcpt, req, hp);
opc = lustre_msg_get_opc(req->rq_reqmsg);
while (req->rq_export != NULL) {
struct obd_export *exp = req->rq_export;
/*
* do search for duplicated xid and the adding to the list
* atomically
*/
spin_lock_bh(&exp->exp_rpc_lock);
/* Cancels are unbounded unlimited requests, they are also
* stateless, so we don't really want to search for duplicates
* as that can take a really long time (under spinlock at that.
* There might be other requests like this and we might want to
* make this code a bit more generic, but this should plug
* the most obious hole for now */
if (opc != LDLM_CANCEL) {
#ifdef CONFIG_LUSTRE_FS_SERVER
ptlrpc_server_mark_in_progress_obsolete(req);
if (req->rq_obsolete) {
spin_unlock_bh(&exp->exp_rpc_lock);
ptlrpc_nrs_req_finalize(req);
RETURN(-EPROTO);
}
#endif
orig = ptlrpc_server_check_resend_in_progress(req);
if (orig && CFS_FAIL_PRECHECK(OBD_FAIL_PTLRPC_RESEND_RACE)) {
spin_unlock_bh(&exp->exp_rpc_lock);
CFS_RACE(OBD_FAIL_PTLRPC_RESEND_RACE);
msleep(4 * MSEC_PER_SEC);
continue;
}
}
if (orig && likely(atomic_inc_not_zero(&orig->rq_refcount))) {
bool linked;
spin_unlock_bh(&exp->exp_rpc_lock);
DEBUG_REQ(D_HA, req,
"Found duplicate req in processing");
DEBUG_REQ(D_HA, orig, "Request being processed");
/*
* When the client resend request and the server has
* the previous copy of it, we need to update deadlines,
* to be sure that the client and the server have equal
* request deadlines.
*/
spin_lock(&orig->rq_rqbd->rqbd_svcpt->scp_at_lock);
linked = orig->rq_at_linked;
if (likely(linked))
ptlrpc_at_remove_timed(orig);
spin_unlock(&orig->rq_rqbd->rqbd_svcpt->scp_at_lock);
orig->rq_deadline = req->rq_deadline;
orig->rq_rep_mbits = req->rq_rep_mbits;
if (likely(linked))
ptlrpc_at_add_timed(orig);
ptlrpc_server_drop_request(orig);
ptlrpc_nrs_req_finalize(req);
/* don't mark slot unused for resend in progress */
spin_lock(&req->rq_lock);
req->rq_obsolete = 1;
spin_unlock(&req->rq_lock);
RETURN(-EBUSY);
}
ptlrpc_add_exp_list_nolock(req, exp, hp || req->rq_ops != NULL);
spin_unlock_bh(&exp->exp_rpc_lock);
break;
}
/*
* the current thread is not the processing thread for this request
* since that, but request is in exp_hp_list and can be find there.
* Remove all relations between request and old thread.
*/
req->rq_svc_thread->t_env->le_ses = NULL;
req->rq_svc_thread = NULL;
req->rq_session.lc_thread = NULL;
ptlrpc_nrs_req_add(svcpt, req, hp);
RETURN(0);
}
/*
* Allow to handle high priority request
* User can call it w/o any lock but need to hold
* ptlrpc_service_part::scp_req_lock to get reliable result
*/
static bool ptlrpc_server_allow_high(struct ptlrpc_service_part *svcpt,
bool force)
{
int running = svcpt->scp_nthrs_running;
if (!nrs_svcpt_has_hp(svcpt))
return false;
if (force)
return true;
if (ptlrpc_nrs_req_throttling_nolock(svcpt, true))
return false;
if (unlikely(svcpt->scp_service->srv_req_portal == MDS_REQUEST_PORTAL &&
CFS_FAIL_PRECHECK(OBD_FAIL_PTLRPC_CANCEL_RESEND))) {
/* leave just 1 thread for normal RPCs */
running = PTLRPC_NTHRS_INIT;
if (svcpt->scp_service->srv_ops.so_hpreq_handler != NULL)
running += 1;
}
if (svcpt->scp_nreqs_active >= running - 1)
return false;
if (svcpt->scp_nhreqs_active == 0)
return true;
return !ptlrpc_nrs_req_pending_nolock(svcpt, false) ||
svcpt->scp_hreq_count < svcpt->scp_service->srv_hpreq_ratio;
}
static bool ptlrpc_server_high_pending(struct ptlrpc_service_part *svcpt,
bool force)
{
return ptlrpc_server_allow_high(svcpt, force) &&
ptlrpc_nrs_req_pending_nolock(svcpt, true);
}
/*
* Only allow normal priority requests on a service that has a high-priority
* queue if forced (i.e. cleanup), if there are other high priority requests
* already being processed (i.e. those threads can service more high-priority
* requests), or if there are enough idle threads that a later thread can do
* a high priority request.
* User can call it w/o any lock but need to hold
* ptlrpc_service_part::scp_req_lock to get reliable result
*/
static bool ptlrpc_server_allow_normal(struct ptlrpc_service_part *svcpt,
bool force)
{
int running = svcpt->scp_nthrs_running;
if (unlikely(svcpt->scp_service->srv_req_portal == MDS_REQUEST_PORTAL &&
CFS_FAIL_PRECHECK(OBD_FAIL_PTLRPC_CANCEL_RESEND))) {
/* leave just 1 thread for normal RPCs */
running = PTLRPC_NTHRS_INIT;
if (svcpt->scp_service->srv_ops.so_hpreq_handler != NULL)
running += 1;
}
if (force)
return true;
if (ptlrpc_nrs_req_throttling_nolock(svcpt, false))
return false;
if (svcpt->scp_nreqs_active < running - 2)
return true;
if (svcpt->scp_nreqs_active >= running - 1)
return false;
return svcpt->scp_nhreqs_active > 0 || !nrs_svcpt_has_hp(svcpt);
}
static bool ptlrpc_server_normal_pending(struct ptlrpc_service_part *svcpt,
bool force)
{
return ptlrpc_server_allow_normal(svcpt, force) &&
ptlrpc_nrs_req_pending_nolock(svcpt, false);
}
/*
* Returns true if there are requests available in incoming
* request queue for processing and it is allowed to fetch them.
* User can call it w/o any lock but need to hold ptlrpc_service::scp_req_lock
* to get reliable result
* see @ptlrpc_server_allow_normal
* see @ptlrpc_server_allow high
*/
static inline
bool ptlrpc_server_request_pending(struct ptlrpc_service_part *svcpt,
bool force)
{
return ptlrpc_server_high_pending(svcpt, force) ||
ptlrpc_server_normal_pending(svcpt, force);
}
/**
* ptlrpc_server_request_get() - Fetch a request for processing from queue of
* unprocessed requests.
* @svcpt: the PTLRPC service partition
* @force: If true Fetch the request regardless (even if it is stuck)
*
* Favors high-priority requests.
*
* Returns a pointer to fetched request else NULL
*/
static struct ptlrpc_request *
ptlrpc_server_request_get(struct ptlrpc_service_part *svcpt, bool force)
{
struct ptlrpc_request *req = NULL;
ENTRY;
spin_lock(&svcpt->scp_req_lock);
if (ptlrpc_server_high_pending(svcpt, force)) {
req = ptlrpc_nrs_req_get_nolock(svcpt, true, force);
if (req != NULL) {
svcpt->scp_hreq_count++;
goto got_request;
}
}
if (ptlrpc_server_normal_pending(svcpt, force)) {
req = ptlrpc_nrs_req_get_nolock(svcpt, false, force);
if (req != NULL) {
svcpt->scp_hreq_count = 0;
goto got_request;
}
}
spin_unlock(&svcpt->scp_req_lock);
RETURN(NULL);
got_request:
svcpt->scp_last_request = ktime_get_real_seconds();
svcpt->scp_nreqs_active++;
if (req->rq_hp)
svcpt->scp_nhreqs_active++;
spin_unlock(&svcpt->scp_req_lock);
if (likely(req->rq_export))
class_export_rpc_inc(req->rq_export);
RETURN(req);
}
/**
* ptlrpc_server_handle_req_in() - Handle freshly incoming reqs
* @svcpt: the PTLRPC service partition
* @thread: ptlrpc thread
*
* Handle freshly incoming reqs, add to timed early reply list, pass on to
* regular request queue. All incoming requests pass through here before getting
* into @ptlrpc_server_handle_req later on.
*
* Return:
* * %0 Request was processed
* * %1 Request not processed or no request available
*/
static int ptlrpc_server_handle_req_in(struct ptlrpc_service_part *svcpt,
struct ptlrpc_thread *thread)
{
struct ptlrpc_service *svc = svcpt->scp_service;
struct ptlrpc_request *req;
__u32 deadline;
__u32 opc;
int rc;
ENTRY;
spin_lock(&svcpt->scp_lock);
if (list_empty(&svcpt->scp_req_incoming)) {
spin_unlock(&svcpt->scp_lock);
RETURN(0);
}
req = list_first_entry(&svcpt->scp_req_incoming,
struct ptlrpc_request, rq_list);
list_del_init(&req->rq_list);
svcpt->scp_nreqs_incoming--;
/*
* Consider this still a "queued" request as far as stats are
* concerned
*/
spin_unlock(&svcpt->scp_lock);
/* go through security check/transform */
CDEBUG(D_RPCTRACE, "unwrap req x%llu\n", req->rq_xid);
rc = sptlrpc_svc_unwrap_request(req);
switch (rc) {
case SECSVC_OK:
break;
case SECSVC_COMPLETE:
target_send_reply(req, 0, OBD_FAIL_MDS_ALL_REPLY_NET);
goto err_req;
case SECSVC_DROP:
goto err_req;
default:
LBUG();
}
/*
* for null-flavored rpc, msg has been unpacked by sptlrpc, although
* redo it wouldn't be harmful.
*/
if (SPTLRPC_FLVR_POLICY(req->rq_flvr.sf_rpc) != SPTLRPC_POLICY_NULL) {
rc = ptlrpc_unpack_req_msg(req, req->rq_reqlen);
if (rc != 0) {
CERROR("error unpacking request: ptl %d from %s x%llu\n",
svc->srv_req_portal, libcfs_idstr(&req->rq_peer),
req->rq_xid);
goto err_req;
}
}
rc = lustre_unpack_req_ptlrpc_body(req, MSG_PTLRPC_BODY_OFF);
if (rc) {
CERROR("error unpacking ptlrpc body: ptl %d from %s x %llu\n",
svc->srv_req_portal, libcfs_idstr(&req->rq_peer),
req->rq_xid);
goto err_req;
}
opc = lustre_msg_get_opc(req->rq_reqmsg);
if (CFS_FAIL_CHECK(OBD_FAIL_PTLRPC_DROP_REQ_OPC) &&
opc == cfs_fail_val) {
CERROR("drop incoming rpc opc %u, x%llu\n",
cfs_fail_val, req->rq_xid);
goto err_req;
}
rc = -EINVAL;
if (lustre_msg_get_type(req->rq_reqmsg) != PTL_RPC_MSG_REQUEST) {
CERROR("wrong packet type received (type=%u) from %s\n",
lustre_msg_get_type(req->rq_reqmsg),
libcfs_idstr(&req->rq_peer));
goto err_req;
}
switch (opc) {
case MDS_WRITEPAGE:
case OST_WRITE:
case OUT_UPDATE:
req->rq_bulk_write = 1;
break;
case MDS_READPAGE:
case OST_READ:
case MGS_CONFIG_READ:
req->rq_bulk_read = 1;
break;
}
CDEBUG(D_RPCTRACE, "got req x%llu\n", req->rq_xid);
req->rq_export = class_conn2export(
lustre_msg_get_handle(req->rq_reqmsg));
if (req->rq_export) {
rc = ptlrpc_check_req(req);
if (rc == 0) {
rc = sptlrpc_target_export_check(req->rq_export, req);
if (rc)
DEBUG_REQ(D_ERROR, req,
"DROPPING req with illegal security flavor");
}
if (rc)
goto err_req;
ptlrpc_update_export_timer(req);
}
/* req_in handling should/must be fast */
if (ktime_get_real_seconds() - req->rq_arrival_time.tv_sec > 5)
DEBUG_REQ(D_WARNING, req, "Slow req_in handling %llds",
ktime_get_real_seconds() -
req->rq_arrival_time.tv_sec);
/* Set rpc server deadline and add it to the timed list */
deadline = (lustre_msghdr_get_flags(req->rq_reqmsg) &
MSGHDR_AT_SUPPORT) ?
/* The max time the client expects us to take */
lustre_msg_get_timeout(req->rq_reqmsg) : obd_timeout;
req->rq_deadline = req->rq_arrival_time.tv_sec + deadline;
if (unlikely(deadline == 0)) {
DEBUG_REQ(D_ERROR, req, "Dropping request with 0 timeout");
goto err_req;
}
/* Skip early reply */
if (CFS_FAIL_PRECHECK(OBD_FAIL_MDS_RESEND))
req->rq_deadline += obd_timeout;
req->rq_svc_thread = thread;
if (thread != NULL) {
/*
* initialize request session, it is needed for request
* processing by target
*/
rc = lu_context_init(&req->rq_session, LCT_SERVER_SESSION |
LCT_NOREF);
if (rc) {
CERROR("%s: failure to initialize session: rc = %d\n",
thread->t_name, rc);
goto err_req;
}
req->rq_session.lc_thread = thread;
lu_context_enter(&req->rq_session);
thread->t_env->le_ses = &req->rq_session;
}
if (unlikely(CFS_FAIL_PRECHECK(OBD_FAIL_PTLRPC_ENQ_RESEND) &&
(opc == LDLM_ENQUEUE) &&
(lustre_msg_get_flags(req->rq_reqmsg) & MSG_RESENT)))
CFS_FAIL_TIMEOUT(OBD_FAIL_PTLRPC_ENQ_RESEND, 6);
ptlrpc_at_add_timed(req);
if (opc != OST_CONNECT && opc != MDS_CONNECT &&
opc != MGS_CONNECT && req->rq_export != NULL) {
if (exp_connect_flags2(req->rq_export) & OBD_CONNECT2_REP_MBITS)
req->rq_rep_mbits = lustre_msg_get_mbits(req->rq_reqmsg);
}
/* Move it over to the request processing queue */
rc = ptlrpc_server_request_add(svcpt, req);
if (rc)
GOTO(err_req, rc);
wake_up(&svcpt->scp_waitq);
RETURN(1);
err_req:
CDEBUG(D_RPCTRACE, "finish req x%llu\n", req->rq_xid);
ptlrpc_server_finish_request(svcpt, req);
RETURN(1);
}
/**
* ptlrpc_server_handle_request() - Main incoming request handling logic
* @svcpt: pointer to struct ptlrpc_service_part
* @thread: pointer to struct ptlrpc_thread(actual handling done by this thread)
*
* Calls handler function from service to do actual processing.
*
* Return:
* * %1 request is processed
* * %0 no request processed or request not available
*/
static int ptlrpc_server_handle_request(struct ptlrpc_service_part *svcpt,
struct ptlrpc_thread *thread)
{
struct ptlrpc_service *svc = svcpt->scp_service;
struct ptlrpc_request *request;
ktime_t work_start;
ktime_t work_end;
ktime_t arrived;
s64 timediff_usecs;
s64 arrived_usecs;
__u32 op;
int fail_opc = 0;
struct obd_device *obd = NULL;
ENTRY;
request = ptlrpc_server_request_get(svcpt, false);
if (request == NULL)
RETURN(0);
if (request->rq_export)
obd = request->rq_export->exp_obd;
op = lustre_msg_get_opc(request->rq_reqmsg);
if (CFS_FAIL_CHECK(OBD_FAIL_PTLRPC_HPREQ_NOTIMEOUT))
fail_opc = OBD_FAIL_PTLRPC_HPREQ_NOTIMEOUT;
else if (CFS_FAIL_CHECK(OBD_FAIL_PTLRPC_HPREQ_TIMEOUT))
fail_opc = OBD_FAIL_PTLRPC_HPREQ_TIMEOUT;
if (unlikely(fail_opc)) {
if (request->rq_export && request->rq_ops)
CFS_FAIL_TIMEOUT(fail_opc, 4);
}
ptlrpc_rqphase_move(request, RQ_PHASE_INTERPRET);
if (CFS_FAIL_CHECK(OBD_FAIL_PTLRPC_DUMP_LOG))
libcfs_debug_dumplog();
work_start = ktime_get_real();
arrived = timespec64_to_ktime(request->rq_arrival_time);
timediff_usecs = ktime_us_delta(work_start, arrived);
if (unlikely(timediff_usecs < 0))
timediff_usecs = 1;
if (likely(svc->srv_stats != NULL)) {
lprocfs_counter_add(svc->srv_stats, PTLRPC_REQWAIT_CNTR,
timediff_usecs);
lprocfs_counter_add(svc->srv_stats, PTLRPC_REQQDEPTH_CNTR,
svcpt->scp_nreqs_incoming);
lprocfs_counter_add(svc->srv_stats, PTLRPC_REQACTIVE_CNTR,
svcpt->scp_nreqs_active);
lprocfs_counter_add(svc->srv_stats, PTLRPC_TIMEOUT,
obd_at_get(obd, &svcpt->scp_at_estimate));
}
if (likely(request->rq_export)) {
if (unlikely(ptlrpc_check_req(request)))
goto put_conn;
ptlrpc_update_export_timer(request);
}
/*
* Discard requests queued for longer than the deadline.
* The deadline is increased if we send an early reply.
*/
if (op != LDLM_CANCEL &&
ktime_get_real_seconds() > request->rq_deadline) {
DEBUG_REQ(D_ERROR, request,
"Dropping timed-out request from %s: deadline %lld/%llds ago",
libcfs_idstr(&request->rq_peer),
request->rq_deadline -
request->rq_arrival_time.tv_sec,
ktime_get_real_seconds() - request->rq_deadline);
goto put_conn;
}
CDEBUG(D_RPCTRACE,
"Handling RPC req@%p pname:cluuid+ref:pid:xid:nid:opc:job %s:%s+%d:%d:x%llu:%s:%d:%s\n",
request, current->comm,
(request->rq_export ?
(char *)request->rq_export->exp_client_uuid.uuid : "0"),
(request->rq_export ?
refcount_read(&request->rq_export->exp_handle.h_ref) : -99),
lustre_msg_get_status(request->rq_reqmsg), request->rq_xid,
libcfs_idstr(&request->rq_peer), op,
lustre_msg_get_jobid(request->rq_reqmsg) ?: "");
if (CFS_FAIL_PRECHECK(OBD_FAIL_PTLRPC_PAUSE_REQ)) {
if (op != OBD_PING && op != OST_STATFS &&
op != MDS_STATFS && op != OST_CREATE &&
op != OST_DISCONNECT) {
DEBUG_REQ(D_ERROR, request, "HIT");
CFS_FAIL_TIMEOUT_MS(OBD_FAIL_PTLRPC_PAUSE_REQ, cfs_fail_val);
}
}
CDEBUG(D_NET, "got req %llu\n", request->rq_xid);
/* re-assign request and sesson thread to the current one */
request->rq_svc_thread = thread;
if (thread != NULL) {
LASSERT(request->rq_session.lc_thread == NULL);
request->rq_session.lc_thread = thread;
thread->t_env->le_ses = &request->rq_session;
}
svc->srv_ops.so_req_handler(request);
ptlrpc_rqphase_move(request, RQ_PHASE_COMPLETE);
put_conn:
if (unlikely(ktime_get_real_seconds() > request->rq_deadline)) {
DEBUG_REQ(D_WARNING, request,
"Request took longer than estimated (%lld/%llds); client may timeout",
request->rq_deadline -
request->rq_arrival_time.tv_sec,
ktime_get_real_seconds() - request->rq_deadline);
}
work_end = ktime_get_real();
timediff_usecs = ktime_us_delta(work_end, work_start);
if (unlikely(timediff_usecs < 0))
timediff_usecs = 1;
arrived_usecs = ktime_us_delta(work_end, arrived);
if (unlikely(arrived_usecs < 0))
arrived_usecs = 1;
CDEBUG(D_RPCTRACE,
"Handled RPC req@%p pname:cluuid+ref:pid:xid:nid:opc:job %s:%s+%d:%d:x%llu:%s:%d:%s Request processed in %lldus (%lldus total) trans %llu rc %d/%d\n",
request, current->comm,
(request->rq_export ?
(char *)request->rq_export->exp_client_uuid.uuid : "0"),
(request->rq_export ?
refcount_read(&request->rq_export->exp_handle.h_ref) : -99),
lustre_msg_get_status(request->rq_reqmsg),
request->rq_xid,
libcfs_idstr(&request->rq_peer), op,
lustre_msg_get_jobid(request->rq_reqmsg) ?: "",
timediff_usecs,
arrived_usecs,
(request->rq_repmsg ?
lustre_msg_get_transno(request->rq_repmsg) :
request->rq_transno),
request->rq_status,
(request->rq_repmsg ?
lustre_msg_get_status(request->rq_repmsg) : -999));
if (likely(svc->srv_stats != NULL && request->rq_reqmsg != NULL)) {
int opc = opcode_offset(op);
if (opc > 0 && !(op == LDLM_ENQUEUE || op == MDS_REINT)) {
LASSERT(opc < LUSTRE_MAX_OPCODES);
lprocfs_counter_add(svc->srv_stats,
opc + EXTRA_MAX_OPCODES,
timediff_usecs);
}
}
if (unlikely(request->rq_early_count)) {
DEBUG_REQ(D_ADAPTTO, request,
"sent %d early replies before finishing in %llds",
request->rq_early_count,
div_u64(arrived_usecs, USEC_PER_SEC));
}
if (unlikely(request->rq_pause_after_reply)) {
DEBUG_REQ(D_WARNING, request, "pause req after reply");
schedule_timeout_uninterruptible(cfs_time_seconds(3));
DEBUG_REQ(D_WARNING, request, "continue");
}
ptlrpc_server_finish_active_request(svcpt, request);
RETURN(1);
}
/* An internal function to process a single reply state object. */
static int ptlrpc_handle_rs(struct ptlrpc_reply_state *rs)
{
struct ptlrpc_service_part *svcpt = rs->rs_svcpt;
struct ptlrpc_service *svc = svcpt->scp_service;
struct obd_export *exp;
int nlocks;
int been_handled;
ENTRY;
exp = rs->rs_export;
LASSERT(rs->rs_difficult);
LASSERT(rs->rs_scheduled);
LASSERT(list_empty(&rs->rs_list));
/*
* The disk commit callback holds exp_uncommitted_replies_lock while it
* iterates over newly committed replies, removing them from
* exp_uncommitted_replies. It then drops this lock and schedules the
* replies it found for handling here.
*
* We can avoid contention for exp_uncommitted_replies_lock between the
* HRT threads and further commit callbacks by checking rs_committed
* which is set in the commit callback while it holds both
* rs_lock and exp_uncommitted_reples.
*
* If we see rs_committed clear, the commit callback _may_ not have
* handled this reply yet and we race with it to grab
* exp_uncommitted_replies_lock before removing the reply from
* exp_uncommitted_replies. Note that if we lose the race and the
* reply has already been removed, list_del_init() is a noop.
*
* If we see rs_committed set, we know the commit callback is handling,
* or has handled this reply since store reordering might allow us to
* see rs_committed set out of sequence. But since this is done
* holding rs_lock, we can be sure it has all completed once we hold
* rs_lock, which we do right next.
*/
if (!rs->rs_committed) {
spin_lock(&exp->exp_uncommitted_replies_lock);
list_del_init(&rs->rs_obd_list);
spin_unlock(&exp->exp_uncommitted_replies_lock);
}
spin_lock(&exp->exp_lock);
/* Noop if removed already */
list_del_init(&rs->rs_exp_list);
spin_unlock(&exp->exp_lock);
spin_lock(&rs->rs_lock);
been_handled = rs->rs_handled;
rs->rs_handled = 1;
nlocks = rs->rs_nlocks; /* atomic "steal", but */
rs->rs_nlocks = 0; /* locks still on rs_locks! */
if (nlocks == 0 && !been_handled) {
/*
* If we see this, we should already have seen the warning
* in mds_steal_ack_locks()
*/
CDEBUG(D_HA,
"All locks stolen from rs %p x%lld.t%lld o%d NID %s\n",
rs, rs->rs_xid, rs->rs_transno, rs->rs_opc,
libcfs_nidstr(&exp->exp_connection->c_peer.nid));
}
if ((rs->rs_sent && !rs->rs_unlinked) || nlocks > 0) {
spin_unlock(&rs->rs_lock);
/* We can unlink if the LNET_EVENT_SEND has occurred.
* If rs_unlinked is set then MD is already unlinked and no
* need to do so here.
*/
if ((rs->rs_sent && !rs->rs_unlinked)) {
LNetMDUnlink(rs->rs_md_h);
/* Ignore return code; we're racing with completion */
}
while (nlocks-- > 0)
ldlm_lock_decref(&rs->rs_locks[nlocks], LCK_TXN);
spin_lock(&rs->rs_lock);
}
rs->rs_scheduled = 0;
if (rs->rs_unlinked) {
/* Off the net */
spin_unlock(&rs->rs_lock);
class_export_put(exp);
rs->rs_export = NULL;
kref_put(&rs->rs_refcount, lustre_free_reply_state);
if (atomic_dec_and_test(&svcpt->scp_nreps_difficult) &&
svc->srv_is_stopping)
wake_up_all(&svcpt->scp_waitq);
RETURN(1);
}
/* still on the net; callback will schedule */
spin_unlock(&rs->rs_lock);
RETURN(1);
}
static void ptlrpc_check_rqbd_pool(struct ptlrpc_service_part *svcpt)
{
int avail = svcpt->scp_nrqbds_posted;
int low_water = test_req_buffer_pressure ? 0 :
svcpt->scp_service->srv_nbuf_per_group / 2;
/* NB I'm not locking; just looking. */
/*
* CAVEAT EMPTOR: We might be allocating buffers here because we've
* allowed the request history to grow out of control. We could put a
* sanity check on that here and cull some history if we need the
* space.
*/
if (avail <= low_water)
ptlrpc_grow_req_bufs(svcpt, 1);
if (svcpt->scp_service->srv_stats) {
lprocfs_counter_add(svcpt->scp_service->srv_stats,
PTLRPC_REQBUF_AVAIL_CNTR, avail);
}
}
static inline int ptlrpc_threads_enough(struct ptlrpc_service_part *svcpt)
{
return svcpt->scp_nreqs_active <
svcpt->scp_nthrs_running - 1 -
(svcpt->scp_service->srv_ops.so_hpreq_handler != NULL);
}
/**
* ptlrpc_threads_increasable() - allowed to create more threads
* @svcpt: the PTLRPC service partition to increase thread
*
* user can call it w/o any lock but need to hold
* ptlrpc_service_part::scp_lock to get reliable result
*
* Return:
* * %0 if it can be increased
* * %1 if it cannot be increased
*/
static inline int ptlrpc_threads_increasable(struct ptlrpc_service_part *svcpt)
{
return svcpt->scp_nthrs_running +
svcpt->scp_nthrs_starting <
svcpt->scp_service->srv_nthrs_cpt_limit;
}
/* too many requests and allowed to create more threads */
static inline int ptlrpc_threads_need_create(struct ptlrpc_service_part *svcpt)
{
return !ptlrpc_threads_enough(svcpt) &&
ptlrpc_threads_increasable(svcpt);
}
static inline int ptlrpc_thread_stopping(struct ptlrpc_thread *thread)
{
return thread_is_stopping(thread) ||
thread->t_svcpt->scp_service->srv_is_stopping;
}
/* stop the highest numbered thread if there are too many threads running */
static inline bool ptlrpc_thread_should_stop(struct ptlrpc_thread *thread)
{
struct ptlrpc_service_part *svcpt = thread->t_svcpt;
return thread->t_id >= svcpt->scp_service->srv_nthrs_cpt_limit &&
thread->t_id == svcpt->scp_thr_nextid - 1;
}
static void ptlrpc_stop_thread(struct ptlrpc_thread *thread)
{
CDEBUG(D_INFO, "Stopping thread %s #%u\n",
thread->t_svcpt->scp_service->srv_thread_name, thread->t_id);
thread_add_flags(thread, SVC_STOPPING);
}
static inline void ptlrpc_thread_stop(struct ptlrpc_thread *thread)
{
struct ptlrpc_service_part *svcpt = thread->t_svcpt;
spin_lock(&svcpt->scp_lock);
if (ptlrpc_thread_should_stop(thread)) {
ptlrpc_stop_thread(thread);
svcpt->scp_thr_nextid--;
}
spin_unlock(&svcpt->scp_lock);
}
static inline int ptlrpc_rqbd_pending(struct ptlrpc_service_part *svcpt)
{
return !list_empty(&svcpt->scp_rqbd_idle) &&
svcpt->scp_rqbd_timeout == 0;
}
static inline int
ptlrpc_at_check(struct ptlrpc_service_part *svcpt)
{
return svcpt->scp_at_check;
}
/*
* If a thread runs too long or spends to much time on a single request,
* we want to know about it, so we set up a delayed work item as a watchdog.
* If it fires, we display a stack trace of the delayed thread,
* providing we aren't rate-limited
*
* Watchdog stack traces are limited to 3 per 'libcfs_watchdog_ratelimit'
* seconds
*/
static struct ratelimit_state watchdog_limit;
static void ptlrpc_watchdog_fire(struct work_struct *work)
{
struct ptlrpc_thread *thread = container_of(work, struct ptlrpc_thread,
t_watchdog.work);
u64 ms_elapsed = ktime_ms_delta(ktime_get(), thread->t_touched);
u32 ms_frac = do_div(ms_elapsed, MSEC_PER_SEC);
thread->t_flags |= SVC_WATCHDOG;
/* ___ratelimit() returns true if the action is NOT ratelimited */
if (__ratelimit(&watchdog_limit)) {
/* below message is checked in sanity-quota.sh test_6,18 */
/* below message is checked in recovery-small test 10a. */
LCONSOLE_WARN("%s: service thread pid %u was inactive for %llu.%03u seconds. The thread might be hung, or it might only be slow and will resume later. Dumping the stack trace for debugging purposes:\n",
thread->t_task->comm, thread->t_task->pid,
ms_elapsed, ms_frac);
sched_show_task(thread->t_task);
} else {
LCONSOLE_WARN("%s: service thread pid %u was inactive for %llu.%03u seconds. Watchdog stack traces are limited to 3 per %u seconds, skipping this one.\n",
thread->t_task->comm, thread->t_task->pid,
ms_elapsed, ms_frac, libcfs_watchdog_ratelimit);
}
}
void ptlrpc_watchdog_init(struct delayed_work *work, timeout_t timeout)
{
struct ptlrpc_thread *thread = container_of(&work->work,
struct ptlrpc_thread,
t_watchdog.work);
thread->t_touched = ktime_get();
INIT_DELAYED_WORK(work, ptlrpc_watchdog_fire);
schedule_delayed_work(work, cfs_time_seconds(timeout));
}
static void ptlrpc_watchdog_update(struct delayed_work *work, const char *msg)
{
struct ptlrpc_thread *thread = container_of(&work->work,
struct ptlrpc_thread,
t_watchdog.work);
ktime_t now = ktime_get();
if (unlikely(thread->t_flags & SVC_WATCHDOG)) {
u64 ms_elapsed = ktime_ms_delta(now, thread->t_touched);
u32 ms_frac = do_div(ms_elapsed, MSEC_PER_SEC);
/* Don't ratelimit this message, since it is already limited
* by the watchdog (obd_timeout) and it is important to know
* if/when a service thread has revived after being hung.
* below message is checked in recovery-small test 10a.
*/
LCONSOLE(D_WARNING,
"%s: service thread pid %u %s after %llu.%03us. This likely indicates the system was overloaded (too many service threads, or not enough hardware resources).\n",
thread->t_task->comm, thread->t_pid, msg,
ms_elapsed, ms_frac);
thread->t_flags &= ~SVC_WATCHDOG;
}
thread->t_touched = now;
}
void ptlrpc_watchdog_touch(struct delayed_work *work, timeout_t timeout)
{
ptlrpc_watchdog_update(work, "resumed");
mod_delayed_work(system_wq, work, cfs_time_seconds(timeout));
}
void ptlrpc_watchdog_disable(struct delayed_work *work)
{
ptlrpc_watchdog_update(work, "completed");
cancel_delayed_work_sync(work);
}
void ptlrpc_watchdog_delete(struct delayed_work *work)
{
ptlrpc_watchdog_update(work, "stopped");
cancel_delayed_work_sync(work);
}
/**
* ptlrpc_server_request_incoming() - check incoming queue for requests which
* is waiting for processing
* @svcpt: pointer to struct ptlrpc_service_part
*
* user can call it w/o any lock but need to hold
* ptlrpc_service_part::scp_lock to get reliable result
*
* Returns:
* * %1 if incoming requests waiting to be processed
* * %0 if incoming request queue is empty
*/
static inline int
ptlrpc_server_request_incoming(struct ptlrpc_service_part *svcpt)
{
return !list_empty(&svcpt->scp_req_incoming);
}
/* We perfer lifo queuing, but kernel doesn't provide that yet. */
#ifndef wait_event_idle_exclusive_lifo
#define wait_event_idle_exclusive_lifo wait_event_idle_exclusive
#define wait_event_idle_exclusive_lifo_timeout wait_event_idle_exclusive_timeout
#endif
static __attribute__((__noinline__)) int
ptlrpc_wait_event(struct ptlrpc_service_part *svcpt,
struct ptlrpc_thread *thread)
{
ptlrpc_watchdog_disable(&thread->t_watchdog);
cond_resched();
if (svcpt->scp_rqbd_timeout == 0)
/* Don't exit while there are replies to be handled */
wait_event_idle_exclusive_lifo(
svcpt->scp_waitq,
ptlrpc_thread_stopping(thread) ||
ptlrpc_server_request_incoming(svcpt) ||
ptlrpc_server_request_pending(svcpt, false) ||
ptlrpc_rqbd_pending(svcpt) ||
ptlrpc_at_check(svcpt));
else if (wait_event_idle_exclusive_lifo_timeout(
svcpt->scp_waitq,
ptlrpc_thread_stopping(thread) ||
ptlrpc_server_request_incoming(svcpt) ||
ptlrpc_server_request_pending(svcpt, false) ||
ptlrpc_rqbd_pending(svcpt) ||
ptlrpc_at_check(svcpt),
svcpt->scp_rqbd_timeout) == 0)
svcpt->scp_rqbd_timeout = 0;
if (ptlrpc_thread_stopping(thread))
return -EINTR;
ptlrpc_watchdog_touch(&thread->t_watchdog,
ptlrpc_server_get_timeout(svcpt));
return 0;
}
/**
* ptlrpc_main() - Main thread body for service threads.
* @arg: pointer to a struct ptlrpc_thread
*
* Waits in a loop waiting for new requests to process to appear.
* Every time an incoming requests is added to its queue, a waitq
* is woken up and one of the threads will handle it.
*
* Returns 0 on success or error code on failure
*/
static int ptlrpc_main(void *arg)
{
struct ptlrpc_thread *thread = (struct ptlrpc_thread *)arg;
struct ptlrpc_service_part *svcpt = thread->t_svcpt;
struct ptlrpc_service *svc = svcpt->scp_service;
struct ptlrpc_reply_state *rs;
struct group_info *ginfo = NULL;
struct lu_env *env;
int counter = 0, rc = 0;
ENTRY;
unshare_fs_struct();
thread->t_task = current;
thread->t_pid = current->pid;
if (svc->srv_cpt_bind) {
rc = cfs_cpt_bind(svc->srv_cptable, svcpt->scp_cpt);
if (rc != 0) {
CWARN("%s: failed to bind %s on CPT %d\n",
svc->srv_name, thread->t_name, svcpt->scp_cpt);
}
}
ginfo = groups_alloc(0);
if (!ginfo)
GOTO(out, rc = -ENOMEM);
set_current_groups(ginfo);
put_group_info(ginfo);
if (svc->srv_ops.so_thr_init != NULL) {
rc = svc->srv_ops.so_thr_init(thread);
if (rc)
GOTO(out, rc);
}
OBD_ALLOC_PTR(env);
if (env == NULL)
GOTO(out_srv_fini, rc = -ENOMEM);
rc = lu_env_add(env);
if (rc)
GOTO(out_env, rc);
rc = lu_context_init(&env->le_ctx,
svc->srv_ctx_tags|LCT_REMEMBER|LCT_NOREF);
if (rc)
GOTO(out_env_remove, rc);
thread->t_env = env;
env->le_ctx.lc_thread = thread;
env->le_ctx.lc_cookie = 0x6;
while (!list_empty(&svcpt->scp_rqbd_idle)) {
rc = ptlrpc_server_post_idle_rqbds(svcpt);
if (rc >= 0)
continue;
CERROR("Failed to post rqbd for %s on CPT %d: %d\n",
svc->srv_name, svcpt->scp_cpt, rc);
GOTO(out_ctx_fini, rc);
}
/* Alloc reply state structure for this one */
OBD_ALLOC_LARGE(rs, svc->srv_max_reply_size);
if (!rs)
GOTO(out_ctx_fini, rc = -ENOMEM);
spin_lock(&svcpt->scp_lock);
LASSERT(thread_is_starting(thread));
thread_clear_flags(thread, SVC_STARTING);
LASSERT(svcpt->scp_nthrs_starting == 1);
svcpt->scp_nthrs_starting--;
/*
* SVC_STOPPING may already be set here if someone else is trying
* to stop the service while this new thread has been dynamically
* forked. We still set SVC_RUNNING to let our creator know that
* we are now running, however we will exit as soon as possible
*/
thread_add_flags(thread, SVC_RUNNING);
svcpt->scp_nthrs_running++;
spin_unlock(&svcpt->scp_lock);
/* wake up our creator in case he's still waiting. */
wake_up(&thread->t_ctl_waitq);
ptlrpc_watchdog_init(&thread->t_watchdog,
ptlrpc_server_get_timeout(svcpt));
spin_lock(&svcpt->scp_rep_lock);
list_add(&rs->rs_list, &svcpt->scp_rep_idle);
wake_up(&svcpt->scp_rep_waitq);
spin_unlock(&svcpt->scp_rep_lock);
CDEBUG(D_NET, "service thread %d (#%d) started\n", thread->t_id,
svcpt->scp_nthrs_running);
/* XXX maintain a list of all managed devices: insert here */
while (!ptlrpc_thread_stopping(thread)) {
if (ptlrpc_wait_event(svcpt, thread))
break;
ptlrpc_check_rqbd_pool(svcpt);
if (ptlrpc_threads_need_create(svcpt)) {
/* Ignore return code - we tried... */
ptlrpc_start_thread(svcpt, 0);
}
/* reset le_ses to initial state */
env->le_ses = NULL;
/* Refill the context before execution to make sure
* all thread keys are allocated */
lu_env_refill(env);
/* Process all incoming reqs before handling any */
if (ptlrpc_server_request_incoming(svcpt)) {
lu_context_enter(&env->le_ctx);
ptlrpc_server_handle_req_in(svcpt, thread);
lu_context_exit(&env->le_ctx);
/* but limit ourselves in case of flood */
if (counter++ < 100)
continue;
counter = 0;
}
if (ptlrpc_at_check(svcpt))
ptlrpc_at_check_timed(svcpt);
if (ptlrpc_server_request_pending(svcpt, false)) {
lu_context_enter(&env->le_ctx);
ptlrpc_server_handle_request(svcpt, thread);
lu_context_exit(&env->le_ctx);
}
if (ptlrpc_rqbd_pending(svcpt) &&
ptlrpc_server_post_idle_rqbds(svcpt) < 0) {
/*
* I just failed to repost request buffers.
* Wait for a timeout (unless something else
* happens) before I try again
*/
svcpt->scp_rqbd_timeout = cfs_time_seconds(1) / 10;
CDEBUG(D_RPCTRACE, "Posted buffers: %d\n",
svcpt->scp_nrqbds_posted);
}
/*
* If the number of threads has been tuned downward and this
* thread should be stopped, then stop in reverse order so the
* the threads always have contiguous thread index values.
*/
if (unlikely(ptlrpc_thread_should_stop(thread)))
ptlrpc_thread_stop(thread);
}
ptlrpc_watchdog_delete(&thread->t_watchdog);
out_ctx_fini:
lu_context_fini(&env->le_ctx);
out_env_remove:
lu_env_remove(env);
out_env:
OBD_FREE_PTR(env);
out_srv_fini:
/* deconstruct service thread state created by ptlrpc_start_thread() */
if (svc->srv_ops.so_thr_done != NULL)
svc->srv_ops.so_thr_done(thread);
out:
CDEBUG(D_RPCTRACE, "%s: service thread [%p:%u] %d exiting: rc = %d\n",
thread->t_name, thread, thread->t_pid, thread->t_id, rc);
spin_lock(&svcpt->scp_lock);
if (thread_test_and_clear_flags(thread, SVC_STARTING))
svcpt->scp_nthrs_starting--;
if (thread_test_and_clear_flags(thread, SVC_RUNNING)) {
/* must know immediately */
svcpt->scp_nthrs_running--;
}
thread->t_id = rc;
thread_add_flags(thread, SVC_STOPPED);
wake_up(&thread->t_ctl_waitq);
spin_unlock(&svcpt->scp_lock);
return rc;
}
static int hrt_dont_sleep(struct ptlrpc_hr_thread *hrt,
struct list_head *replies)
{
int result;
spin_lock(&hrt->hrt_lock);
list_splice_init(&hrt->hrt_queue, replies);
result = ptlrpc_hr.hr_stopping || !list_empty(replies);
spin_unlock(&hrt->hrt_lock);
return result;
}
/**
* ptlrpc_hr_main() - Main body of "handle reply" function.
* @arg: Pointer to struct 'ptlrpc_hr_thread'
*
* It processes acked reply states
*
* Returns:
* * %0 on success
* * %ERRNO on failure
*/
static int ptlrpc_hr_main(void *arg)
{
struct ptlrpc_hr_thread *hrt = (struct ptlrpc_hr_thread *)arg;
struct ptlrpc_hr_partition *hrp = hrt->hrt_partition;
LIST_HEAD(replies);
struct lu_env *env;
int rc;
unshare_fs_struct();
OBD_ALLOC_PTR(env);
if (env == NULL)
RETURN(-ENOMEM);
rc = cfs_cpt_bind(ptlrpc_hr.hr_cpt_table, hrp->hrp_cpt);
if (rc != 0) {
char threadname[20];
snprintf(threadname, sizeof(threadname), "ptlrpc_hr%02d_%03d",
hrp->hrp_cpt, hrt->hrt_id);
CWARN("Failed to bind %s on CPT %d of CPT table %p: rc = %d\n",
threadname, hrp->hrp_cpt, ptlrpc_hr.hr_cpt_table, rc);
}
rc = lu_context_init(&env->le_ctx, LCT_MD_THREAD | LCT_DT_THREAD |
LCT_REMEMBER | LCT_NOREF);
if (rc)
GOTO(out_env, rc);
rc = lu_env_add(env);
if (rc)
GOTO(out_ctx_fini, rc);
atomic_inc(&hrp->hrp_nstarted);
wake_up(&ptlrpc_hr.hr_waitq);
while (!ptlrpc_hr.hr_stopping) {
wait_event_idle(hrt->hrt_waitq, hrt_dont_sleep(hrt, &replies));
while (!list_empty(&replies)) {
struct ptlrpc_reply_state *rs;
rs = list_entry(replies.prev,
struct ptlrpc_reply_state,
rs_list);
list_del_init(&rs->rs_list);
/* refill keys if needed */
lu_env_refill(env);
lu_context_enter(&env->le_ctx);
ptlrpc_handle_rs(rs);
lu_context_exit(&env->le_ctx);
}
}
atomic_inc(&hrp->hrp_nstopped);
wake_up(&ptlrpc_hr.hr_waitq);
lu_env_remove(env);
out_ctx_fini:
lu_context_fini(&env->le_ctx);
out_env:
OBD_FREE_PTR(env);
return 0;
}
static void ptlrpc_stop_hr_threads(void)
{
struct ptlrpc_hr_partition *hrp;
int i;
int j;
ptlrpc_hr.hr_stopping = 1;
cfs_percpt_for_each(hrp, i, ptlrpc_hr.hr_partitions) {
if (hrp->hrp_thrs == NULL)
continue; /* uninitialized */
for (j = 0; j < hrp->hrp_nthrs; j++)
wake_up(&hrp->hrp_thrs[j].hrt_waitq);
}
cfs_percpt_for_each(hrp, i, ptlrpc_hr.hr_partitions) {
if (hrp->hrp_thrs == NULL)
continue; /* uninitialized */
wait_event(ptlrpc_hr.hr_waitq,
atomic_read(&hrp->hrp_nstopped) ==
atomic_read(&hrp->hrp_nstarted));
}
}
static int ptlrpc_start_hr_threads(void)
{
struct ptlrpc_hr_partition *hrp;
int i;
int j;
ENTRY;
cfs_percpt_for_each(hrp, i, ptlrpc_hr.hr_partitions) {
int rc = 0;
for (j = 0; j < hrp->hrp_nthrs; j++) {
struct ptlrpc_hr_thread *hrt = &hrp->hrp_thrs[j];
struct task_struct *task;
task = kthread_run(ptlrpc_hr_main,
&hrp->hrp_thrs[j],
"ptlrpc_hr%02d_%03d",
hrp->hrp_cpt,
hrt->hrt_id);
if (IS_ERR(task)) {
rc = PTR_ERR(task);
break;
}
}
wait_event(ptlrpc_hr.hr_waitq,
atomic_read(&hrp->hrp_nstarted) == j);
if (rc < 0) {
CERROR("cannot start reply handler thread %d:%d: rc = %d\n",
i, j, rc);
ptlrpc_stop_hr_threads();
RETURN(rc);
}
}
RETURN(0);
}
static void ptlrpc_svcpt_stop_threads(struct ptlrpc_service_part *svcpt)
{
struct ptlrpc_thread *thread;
LIST_HEAD(zombie);
ENTRY;
CDEBUG(D_INFO, "Stopping threads for service %s\n",
svcpt->scp_service->srv_name);
spin_lock(&svcpt->scp_lock);
/* let the thread know that we would like it to stop asap */
list_for_each_entry(thread, &svcpt->scp_threads, t_link)
ptlrpc_stop_thread(thread);
wake_up_all(&svcpt->scp_waitq);
while ((thread = list_first_entry_or_null(&svcpt->scp_threads,
struct ptlrpc_thread,
t_link)) != NULL) {
if (thread_is_stopped(thread)) {
list_move(&thread->t_link, &zombie);
continue;
}
spin_unlock(&svcpt->scp_lock);
CDEBUG(D_INFO, "waiting for stopping-thread %s #%u\n",
svcpt->scp_service->srv_thread_name, thread->t_id);
wait_event_idle(thread->t_ctl_waitq,
thread_is_stopped(thread));
spin_lock(&svcpt->scp_lock);
}
spin_unlock(&svcpt->scp_lock);
while ((thread = list_first_entry_or_null(&zombie,
struct ptlrpc_thread,
t_link)) != NULL) {
list_del(&thread->t_link);
OBD_FREE_PTR(thread);
}
EXIT;
}
/* Stops all threads of a particular service @svc */
static void ptlrpc_stop_all_threads(struct ptlrpc_service *svc)
{
struct ptlrpc_service_part *svcpt;
int i;
ENTRY;
ptlrpc_service_for_each_part(svcpt, i, svc) {
if (svcpt->scp_service != NULL)
ptlrpc_svcpt_stop_threads(svcpt);
}
EXIT;
}
static int ptlrpc_start_threads(struct ptlrpc_service *svc)
{
int rc = 0;
int i;
int j;
ENTRY;
/* We require 2 threads min, see note in ptlrpc_server_handle_request */
LASSERT(svc->srv_nthrs_cpt_init >= PTLRPC_NTHRS_INIT);
for (i = 0; i < svc->srv_ncpts; i++) {
for (j = 0; j < svc->srv_nthrs_cpt_init; j++) {
rc = ptlrpc_start_thread(svc->srv_parts[i], 1);
if (rc == 0)
continue;
if (rc != -EMFILE)
goto failed;
/* We have enough threads, don't start more. b=15759 */
break;
}
}
RETURN(0);
failed:
CERROR("cannot start %s thread #%d_%d: rc %d\n",
svc->srv_thread_name, i, j, rc);
ptlrpc_stop_all_threads(svc);
RETURN(rc);
}
static int ptlrpc_start_thread(struct ptlrpc_service_part *svcpt, int wait)
{
struct ptlrpc_thread *thread;
struct ptlrpc_service *svc;
struct task_struct *task;
int rc;
ENTRY;
LASSERT(svcpt != NULL);
svc = svcpt->scp_service;
CDEBUG(D_RPCTRACE, "%s[%d] started %d min %d max %d\n",
svc->srv_name, svcpt->scp_cpt, svcpt->scp_nthrs_running,
svc->srv_nthrs_cpt_init, svc->srv_nthrs_cpt_limit);
again:
if (unlikely(svc->srv_is_stopping))
RETURN(-ESRCH);
if (!ptlrpc_threads_increasable(svcpt) ||
(CFS_FAIL_CHECK(OBD_FAIL_TGT_TOOMANY_THREADS) &&
svcpt->scp_nthrs_running == svc->srv_nthrs_cpt_init - 1))
RETURN(-EMFILE);
OBD_CPT_ALLOC_PTR(thread, svc->srv_cptable, svcpt->scp_cpt);
if (thread == NULL)
RETURN(-ENOMEM);
init_waitqueue_head(&thread->t_ctl_waitq);
spin_lock(&svcpt->scp_lock);
if (!ptlrpc_threads_increasable(svcpt)) {
spin_unlock(&svcpt->scp_lock);
OBD_FREE_PTR(thread);
RETURN(-EMFILE);
}
if (svcpt->scp_nthrs_starting != 0) {
/*
* serialize starting because some modules (obdfilter)
* might require unique and contiguous t_id
*/
LASSERT(svcpt->scp_nthrs_starting == 1);
spin_unlock(&svcpt->scp_lock);
OBD_FREE_PTR(thread);
if (wait) {
CDEBUG(D_INFO, "Waiting for creating thread %s #%d\n",
svc->srv_thread_name, svcpt->scp_thr_nextid);
schedule();
goto again;
}
CDEBUG(D_INFO, "Creating thread %s #%d race, retry later\n",
svc->srv_thread_name, svcpt->scp_thr_nextid);
RETURN(-EAGAIN);
}
svcpt->scp_nthrs_starting++;
thread->t_id = svcpt->scp_thr_nextid++;
thread_add_flags(thread, SVC_STARTING);
thread->t_svcpt = svcpt;
list_add(&thread->t_link, &svcpt->scp_threads);
spin_unlock(&svcpt->scp_lock);
if (svcpt->scp_cpt >= 0) {
snprintf(thread->t_name, PTLRPC_THR_NAME_LEN, "%s%02d_%03d",
svc->srv_thread_name, svcpt->scp_cpt, thread->t_id);
} else {
snprintf(thread->t_name, PTLRPC_THR_NAME_LEN, "%s_%04d",
svc->srv_thread_name, thread->t_id);
}
CDEBUG(D_RPCTRACE, "starting thread '%s'\n", thread->t_name);
task = kthread_run(ptlrpc_main, thread, "%s", thread->t_name);
if (IS_ERR(task)) {
rc = PTR_ERR(task);
CERROR("cannot start thread '%s': rc = %d\n",
thread->t_name, rc);
spin_lock(&svcpt->scp_lock);
--svcpt->scp_nthrs_starting;
if (thread_is_stopping(thread)) {
/* thread now handled by ptlrpc_svcpt_stop_threads() */
thread_add_flags(thread, SVC_STOPPED);
wake_up(&thread->t_ctl_waitq);
spin_unlock(&svcpt->scp_lock);
} else {
list_del(&thread->t_link);
spin_unlock(&svcpt->scp_lock);
OBD_FREE_PTR(thread);
}
RETURN(rc);
}
if (!wait)
RETURN(0);
wait_event_idle(thread->t_ctl_waitq,
thread_is_running(thread) || thread_is_stopped(thread));
rc = thread_is_stopped(thread) ? thread->t_id : 0;
RETURN(rc);
}
int ptlrpc_hr_init(void)
{
struct ptlrpc_hr_partition *hrp;
struct ptlrpc_hr_thread *hrt;
int rc;
int cpt;
int i;
int weight;
ENTRY;
memset(&ptlrpc_hr, 0, sizeof(ptlrpc_hr));
ptlrpc_hr.hr_cpt_table = cfs_cpt_tab;
ptlrpc_hr.hr_partitions = cfs_percpt_alloc(ptlrpc_hr.hr_cpt_table,
sizeof(*hrp));
if (ptlrpc_hr.hr_partitions == NULL)
RETURN(-ENOMEM);
ratelimit_state_init(&watchdog_limit,
cfs_time_seconds(libcfs_watchdog_ratelimit), 3);
init_waitqueue_head(&ptlrpc_hr.hr_waitq);
preempt_disable();
weight = cpumask_weight(topology_sibling_cpumask(smp_processor_id()));
preempt_enable();
cfs_percpt_for_each(hrp, cpt, ptlrpc_hr.hr_partitions) {
hrp->hrp_cpt = cpt;
atomic_set(&hrp->hrp_nstarted, 0);
atomic_set(&hrp->hrp_nstopped, 0);
hrp->hrp_nthrs = cfs_cpt_weight(ptlrpc_hr.hr_cpt_table, cpt);
hrp->hrp_nthrs /= weight;
if (hrp->hrp_nthrs == 0)
hrp->hrp_nthrs = 1;
OBD_CPT_ALLOC(hrp->hrp_thrs, ptlrpc_hr.hr_cpt_table, cpt,
hrp->hrp_nthrs * sizeof(*hrt));
if (hrp->hrp_thrs == NULL)
GOTO(out, rc = -ENOMEM);
for (i = 0; i < hrp->hrp_nthrs; i++) {
hrt = &hrp->hrp_thrs[i];
hrt->hrt_id = i;
hrt->hrt_partition = hrp;
init_waitqueue_head(&hrt->hrt_waitq);
spin_lock_init(&hrt->hrt_lock);
INIT_LIST_HEAD(&hrt->hrt_queue);
}
}
rc = ptlrpc_start_hr_threads();
out:
if (rc != 0)
ptlrpc_hr_fini();
RETURN(rc);
}
void ptlrpc_hr_fini(void)
{
struct ptlrpc_hr_partition *hrp;
int cpt;
if (ptlrpc_hr.hr_partitions == NULL)
return;
ptlrpc_stop_hr_threads();
cfs_percpt_for_each(hrp, cpt, ptlrpc_hr.hr_partitions) {
if (hrp->hrp_thrs)
OBD_FREE_PTR_ARRAY(hrp->hrp_thrs, hrp->hrp_nthrs);
}
cfs_percpt_free(ptlrpc_hr.hr_partitions);
ptlrpc_hr.hr_partitions = NULL;
}
/* Wait until all already scheduled replies are processed */
static void ptlrpc_wait_replies(struct ptlrpc_service_part *svcpt)
{
while (1) {
if (wait_event_idle_timeout(
svcpt->scp_waitq,
atomic_read(&svcpt->scp_nreps_difficult) == 0,
cfs_time_seconds(10)) > 0)
break;
CWARN("Unexpectedly long timeout %s %p\n",
svcpt->scp_service->srv_name, svcpt->scp_service);
}
}
static void
ptlrpc_service_del_atimer(struct ptlrpc_service *svc)
{
struct ptlrpc_service_part *svcpt;
int i;
/* early disarm AT timer... */
ptlrpc_service_for_each_part(svcpt, i, svc) {
if (svcpt->scp_service != NULL)
timer_delete(&svcpt->scp_at_timer);
}
}
static void
ptlrpc_service_unlink_rqbd(struct ptlrpc_service *svc)
{
struct ptlrpc_service_part *svcpt;
struct ptlrpc_request_buffer_desc *rqbd;
int rc;
int i;
/*
* All history will be culled when the next request buffer is
* freed in ptlrpc_service_purge_all()
*/
svc->srv_hist_nrqbds_cpt_max = 0;
rc = LNetClearLazyPortal(svc->srv_req_portal);
LASSERT(rc == 0);
ptlrpc_service_for_each_part(svcpt, i, svc) {
if (svcpt->scp_service == NULL)
break;
/*
* Unlink all the request buffers. This forces a 'final'
* event with its 'unlink' flag set for each posted rqbd
*/
list_for_each_entry(rqbd, &svcpt->scp_rqbd_posted,
rqbd_list) {
rc = LNetMDUnlink(rqbd->rqbd_md_h);
LASSERT(rc == 0 || rc == -ENOENT);
}
}
ptlrpc_service_for_each_part(svcpt, i, svc) {
if (svcpt->scp_service == NULL)
break;
/*
* Wait for the network to release any buffers
* it's currently filling
*/
spin_lock(&svcpt->scp_lock);
while (svcpt->scp_nrqbds_posted != 0) {
int seconds = PTLRPC_REQ_LONG_UNLINK;
spin_unlock(&svcpt->scp_lock);
/*
* Network access will complete in finite time but
* the HUGE timeout lets us CWARN for visibility
* of sluggish NALs
*/
while (seconds > 0 &&
wait_event_idle_timeout(
svcpt->scp_waitq,
svcpt->scp_nrqbds_posted == 0,
cfs_time_seconds(1)) == 0)
seconds -= 1;
if (seconds == 0) {
CWARN("Service %s waiting for request buffers\n",
svcpt->scp_service->srv_name);
}
spin_lock(&svcpt->scp_lock);
}
spin_unlock(&svcpt->scp_lock);
}
}
static void
ptlrpc_service_purge_all(struct ptlrpc_service *svc)
{
struct ptlrpc_service_part *svcpt;
struct ptlrpc_request_buffer_desc *rqbd;
struct ptlrpc_request *req;
struct ptlrpc_reply_state *rs;
int i;
ptlrpc_service_for_each_part(svcpt, i, svc) {
if (svcpt->scp_service == NULL)
break;
spin_lock(&svcpt->scp_rep_lock);
while ((rs = list_first_entry_or_null(&svcpt->scp_rep_active,
struct ptlrpc_reply_state,
rs_list)) != NULL) {
spin_lock(&rs->rs_lock);
ptlrpc_schedule_difficult_reply(rs);
spin_unlock(&rs->rs_lock);
}
spin_unlock(&svcpt->scp_rep_lock);
/*
* purge the request queue. NB No new replies (rqbds
* all unlinked) and no service threads, so I'm the only
* thread noodling the request queue now
*/
while ((req = list_first_entry_or_null(&svcpt->scp_req_incoming,
struct ptlrpc_request,
rq_list)) != NULL) {
list_del(&req->rq_list);
svcpt->scp_nreqs_incoming--;
ptlrpc_server_finish_request(svcpt, req);
}
while (ptlrpc_server_request_pending(svcpt, true)) {
req = ptlrpc_server_request_get(svcpt, true);
LASSERT(req);
ptlrpc_server_finish_active_request(svcpt, req);
}
/*
* The portal may be shared by several services (eg:OUT_PORTAL).
* So the request could be referenced by other target. So we
* have to wait the ptlrpc_server_drop_request invoked.
*
* TODO: move the req_buffer as global rather than per service.
*/
spin_lock(&svcpt->scp_lock);
while (!list_empty(&svcpt->scp_rqbd_posted)) {
spin_unlock(&svcpt->scp_lock);
wait_event_idle_timeout(svcpt->scp_waitq,
list_empty(&svcpt->scp_rqbd_posted),
cfs_time_seconds(1));
spin_lock(&svcpt->scp_lock);
}
spin_unlock(&svcpt->scp_lock);
LASSERT(svcpt->scp_nreqs_incoming == 0);
LASSERT(svcpt->scp_nreqs_active == 0);
/*
* history should have been culled by
* ptlrpc_server_finish_request
*/
LASSERT(svcpt->scp_hist_nrqbds == 0);
/*
* Now free all the request buffers since nothing
* references them any more...
*/
spin_lock(&svcpt->scp_lock);
while ((rqbd = list_first_entry_or_null(&svcpt->scp_rqbd_idle,
struct ptlrpc_request_buffer_desc,
rqbd_list)) != NULL) {
list_del(&rqbd->rqbd_list);
svcpt->scp_nrqbds_total--;
spin_unlock(&svcpt->scp_lock);
ptlrpc_free_rqbd(rqbd);
spin_lock(&svcpt->scp_lock);
}
spin_unlock(&svcpt->scp_lock);
ptlrpc_wait_replies(svcpt);
while ((rs = list_first_entry_or_null(&svcpt->scp_rep_idle,
struct ptlrpc_reply_state,
rs_list)) != NULL) {
list_del(&rs->rs_list);
OBD_FREE_LARGE(rs, svc->srv_max_reply_size);
}
}
}
static void
ptlrpc_service_free(struct ptlrpc_service *svc)
{
struct ptlrpc_service_part *svcpt;
struct ptlrpc_at_array *array;
int i;
ptlrpc_service_for_each_part(svcpt, i, svc) {
if (svcpt->scp_service == NULL)
break;
/* In case somebody rearmed this in the meantime */
timer_delete(&svcpt->scp_at_timer);
array = &svcpt->scp_at_array;
if (array->paa_reqs_array != NULL) {
OBD_FREE_PTR_ARRAY(array->paa_reqs_array,
array->paa_size);
array->paa_reqs_array = NULL;
}
if (array->paa_reqs_count != NULL) {
OBD_FREE_PTR_ARRAY(array->paa_reqs_count,
array->paa_size);
array->paa_reqs_count = NULL;
}
}
ptlrpc_service_for_each_part(svcpt, i, svc)
OBD_FREE_PTR(svcpt);
if (svc->srv_cpts != NULL)
cfs_expr_list_values_free(svc->srv_cpts, svc->srv_ncpts);
OBD_FREE(svc, offsetof(struct ptlrpc_service,
srv_parts[svc->srv_ncpts]));
}
int ptlrpc_unregister_service(struct ptlrpc_service *service)
{
ENTRY;
CDEBUG(D_NET, "%s: tearing down\n", service->srv_name);
service->srv_is_stopping = 1;
mutex_lock(&ptlrpc_all_services_mutex);
list_del_init(&service->srv_list);
mutex_unlock(&ptlrpc_all_services_mutex);
ptlrpc_service_del_atimer(service);
ptlrpc_stop_all_threads(service);
ptlrpc_service_unlink_rqbd(service);
ptlrpc_service_purge_all(service);
ptlrpc_service_nrs_cleanup(service);
ptlrpc_lprocfs_unregister_service(service);
ptlrpc_sysfs_unregister_service(service);
ptlrpc_service_free(service);
RETURN(0);
}
EXPORT_SYMBOL(ptlrpc_unregister_service);
/**
* ptlrpc_svcpt_health_check() - checks the health of a PTLRPC service
* @svcpt: PTLRPC service partition structure to be cecked for health
*
* Check whether requests have been waiting in the queue for an excessive
* time without being processed. Individual requests may wait in the queue
* for some time due to NRS policies, overloaded storage, etc. but the queue
* itself should continue to process some requests on a regular basis.
*
* We'll use this health check to govern whether a node needs to be shot,
* so it's intentionally non-aggressive.
*
* Returns:
* * %0 if the service is healthy.
* * %negative if the service is not healthy.
*/
static int ptlrpc_svcpt_health_check(struct ptlrpc_service_part *svcpt)
{
struct ptlrpc_request *request = NULL;
struct obd_device *obd = NULL;
time64_t right_now;
time64_t req_waited;
time64_t svc_waited;
bool recovering;
unsigned int max;
/* quick check without locking to handle the most common case */
right_now = ktime_get_real_seconds();
if (likely(right_now - svcpt->scp_last_request < obd_get_at_max(NULL)))
return 0;
spin_lock(&svcpt->scp_req_lock);
if (ptlrpc_server_high_pending(svcpt, true))
request = ptlrpc_nrs_req_peek_nolock(svcpt, true);
else if (ptlrpc_server_normal_pending(svcpt, true))
request = ptlrpc_nrs_req_peek_nolock(svcpt, false);
/* if no waiting requests, service idle time is irrelevant */
if (request == NULL) {
spin_unlock(&svcpt->scp_req_lock);
return 0;
}
if (request->rq_export)
obd = request->rq_export->exp_obd;
req_waited = right_now - request->rq_arrival_time.tv_sec;
svc_waited = right_now - svcpt->scp_last_request;
recovering = obd ? test_bit(OBDF_RECOVERING, obd->obd_flags) : false;
spin_unlock(&svcpt->scp_req_lock);
max = obd_get_at_max(obd);
if (min(req_waited, svc_waited) > max && !recovering) {
bool unhealthy = false;
/* if at_unhealthy_factor = 0 then disable unhealthy status but
* at least print a warning if requests are stuck for a while
*/
if (obd_get_at_unhealthy_factor(obd) &&
svc_waited > max * obd_get_at_unhealthy_factor(obd)) {
/* check if other CPTs in svc also unhealthy? */
unhealthy = true;
}
CDEBUG_LIMIT(unhealthy ? D_ERROR : D_WARNING,
"%s: %s - request waiting %llus, service %llus\n",
obd ? obd->obd_name : svcpt->scp_service->srv_name,
unhealthy ? "unhealthy" : "notice",
req_waited, svc_waited);
if (unhealthy)
return -1;
}
return 0;
}
int
ptlrpc_service_health_check(struct ptlrpc_service *svc)
{
struct ptlrpc_service_part *svcpt;
int i;
if (svc == NULL)
return 0;
ptlrpc_service_for_each_part(svcpt, i, svc) {
int rc = ptlrpc_svcpt_health_check(svcpt);
if (rc != 0)
return rc;
}
return 0;
}
EXPORT_SYMBOL(ptlrpc_service_health_check);
int
ptlrpc_server_get_timeout(struct ptlrpc_service_part *svcpt)
{
int at = 0;
if (!obd_at_off(NULL))
at = obd_at_get(NULL, &svcpt->scp_at_estimate);
return svcpt->scp_service->srv_watchdog_factor *
max_t(int, at, obd_timeout);
}
