tmp_suning_uos_patched/fs/ceph/metric.c
Jeff Layton e418ce8b8d ceph: cancel delayed work instead of flushing on mdsc teardown
[ Upstream commit b4002173b7989588b6feaefc42edaf011b596782 ]

The first thing metric_delayed_work does is check mdsc->stopping,
and then return immediately if it's set. That's good since we would
have already torn down the metric structures at this point, otherwise,
but there is no locking around mdsc->stopping.

It's possible that the ceph_metric_destroy call could race with the
delayed_work, in which case we could end up with the delayed_work
accessing destroyed percpu variables.

At this point in the mdsc teardown, the "stopping" flag has already been
set, so there's no benefit to flushing the work. Move the work
cancellation in ceph_metric_destroy ahead of the percpu variable
destruction, and eliminate the flush_delayed_work call in
ceph_mdsc_destroy.

Fixes: 18f473b384 ("ceph: periodically send perf metrics to MDSes")
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-09-26 14:08:58 +02:00

311 lines
7.9 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#include <linux/ceph/ceph_debug.h>
#include <linux/types.h>
#include <linux/percpu_counter.h>
#include <linux/math64.h>
#include "metric.h"
#include "mds_client.h"
static bool ceph_mdsc_send_metrics(struct ceph_mds_client *mdsc,
struct ceph_mds_session *s)
{
struct ceph_metric_head *head;
struct ceph_metric_cap *cap;
struct ceph_metric_read_latency *read;
struct ceph_metric_write_latency *write;
struct ceph_metric_metadata_latency *meta;
struct ceph_client_metric *m = &mdsc->metric;
u64 nr_caps = atomic64_read(&m->total_caps);
struct ceph_msg *msg;
struct timespec64 ts;
s64 sum;
s32 items = 0;
s32 len;
len = sizeof(*head) + sizeof(*cap) + sizeof(*read) + sizeof(*write)
+ sizeof(*meta);
msg = ceph_msg_new(CEPH_MSG_CLIENT_METRICS, len, GFP_NOFS, true);
if (!msg) {
pr_err("send metrics to mds%d, failed to allocate message\n",
s->s_mds);
return false;
}
head = msg->front.iov_base;
/* encode the cap metric */
cap = (struct ceph_metric_cap *)(head + 1);
cap->type = cpu_to_le32(CLIENT_METRIC_TYPE_CAP_INFO);
cap->ver = 1;
cap->compat = 1;
cap->data_len = cpu_to_le32(sizeof(*cap) - 10);
cap->hit = cpu_to_le64(percpu_counter_sum(&mdsc->metric.i_caps_hit));
cap->mis = cpu_to_le64(percpu_counter_sum(&mdsc->metric.i_caps_mis));
cap->total = cpu_to_le64(nr_caps);
items++;
/* encode the read latency metric */
read = (struct ceph_metric_read_latency *)(cap + 1);
read->type = cpu_to_le32(CLIENT_METRIC_TYPE_READ_LATENCY);
read->ver = 1;
read->compat = 1;
read->data_len = cpu_to_le32(sizeof(*read) - 10);
sum = m->read_latency_sum;
jiffies_to_timespec64(sum, &ts);
read->sec = cpu_to_le32(ts.tv_sec);
read->nsec = cpu_to_le32(ts.tv_nsec);
items++;
/* encode the write latency metric */
write = (struct ceph_metric_write_latency *)(read + 1);
write->type = cpu_to_le32(CLIENT_METRIC_TYPE_WRITE_LATENCY);
write->ver = 1;
write->compat = 1;
write->data_len = cpu_to_le32(sizeof(*write) - 10);
sum = m->write_latency_sum;
jiffies_to_timespec64(sum, &ts);
write->sec = cpu_to_le32(ts.tv_sec);
write->nsec = cpu_to_le32(ts.tv_nsec);
items++;
/* encode the metadata latency metric */
meta = (struct ceph_metric_metadata_latency *)(write + 1);
meta->type = cpu_to_le32(CLIENT_METRIC_TYPE_METADATA_LATENCY);
meta->ver = 1;
meta->compat = 1;
meta->data_len = cpu_to_le32(sizeof(*meta) - 10);
sum = m->metadata_latency_sum;
jiffies_to_timespec64(sum, &ts);
meta->sec = cpu_to_le32(ts.tv_sec);
meta->nsec = cpu_to_le32(ts.tv_nsec);
items++;
put_unaligned_le32(items, &head->num);
msg->front.iov_len = len;
msg->hdr.version = cpu_to_le16(1);
msg->hdr.compat_version = cpu_to_le16(1);
msg->hdr.front_len = cpu_to_le32(msg->front.iov_len);
dout("client%llu send metrics to mds%d\n",
ceph_client_gid(mdsc->fsc->client), s->s_mds);
ceph_con_send(&s->s_con, msg);
return true;
}
static void metric_get_session(struct ceph_mds_client *mdsc)
{
struct ceph_mds_session *s;
int i;
mutex_lock(&mdsc->mutex);
for (i = 0; i < mdsc->max_sessions; i++) {
s = __ceph_lookup_mds_session(mdsc, i);
if (!s)
continue;
/*
* Skip it if MDS doesn't support the metric collection,
* or the MDS will close the session's socket connection
* directly when it get this message.
*/
if (check_session_state(s) &&
test_bit(CEPHFS_FEATURE_METRIC_COLLECT, &s->s_features)) {
mdsc->metric.session = s;
break;
}
ceph_put_mds_session(s);
}
mutex_unlock(&mdsc->mutex);
}
static void metric_delayed_work(struct work_struct *work)
{
struct ceph_client_metric *m =
container_of(work, struct ceph_client_metric, delayed_work.work);
struct ceph_mds_client *mdsc =
container_of(m, struct ceph_mds_client, metric);
if (mdsc->stopping)
return;
if (!m->session || !check_session_state(m->session)) {
if (m->session) {
ceph_put_mds_session(m->session);
m->session = NULL;
}
metric_get_session(mdsc);
}
if (m->session) {
ceph_mdsc_send_metrics(mdsc, m->session);
metric_schedule_delayed(m);
}
}
int ceph_metric_init(struct ceph_client_metric *m)
{
int ret;
if (!m)
return -EINVAL;
atomic64_set(&m->total_dentries, 0);
ret = percpu_counter_init(&m->d_lease_hit, 0, GFP_KERNEL);
if (ret)
return ret;
ret = percpu_counter_init(&m->d_lease_mis, 0, GFP_KERNEL);
if (ret)
goto err_d_lease_mis;
atomic64_set(&m->total_caps, 0);
ret = percpu_counter_init(&m->i_caps_hit, 0, GFP_KERNEL);
if (ret)
goto err_i_caps_hit;
ret = percpu_counter_init(&m->i_caps_mis, 0, GFP_KERNEL);
if (ret)
goto err_i_caps_mis;
spin_lock_init(&m->read_latency_lock);
m->read_latency_sq_sum = 0;
m->read_latency_min = KTIME_MAX;
m->read_latency_max = 0;
m->total_reads = 0;
m->read_latency_sum = 0;
spin_lock_init(&m->write_latency_lock);
m->write_latency_sq_sum = 0;
m->write_latency_min = KTIME_MAX;
m->write_latency_max = 0;
m->total_writes = 0;
m->write_latency_sum = 0;
spin_lock_init(&m->metadata_latency_lock);
m->metadata_latency_sq_sum = 0;
m->metadata_latency_min = KTIME_MAX;
m->metadata_latency_max = 0;
m->total_metadatas = 0;
m->metadata_latency_sum = 0;
atomic64_set(&m->opened_files, 0);
ret = percpu_counter_init(&m->opened_inodes, 0, GFP_KERNEL);
if (ret)
goto err_opened_inodes;
ret = percpu_counter_init(&m->total_inodes, 0, GFP_KERNEL);
if (ret)
goto err_total_inodes;
m->session = NULL;
INIT_DELAYED_WORK(&m->delayed_work, metric_delayed_work);
return 0;
err_total_inodes:
percpu_counter_destroy(&m->opened_inodes);
err_opened_inodes:
percpu_counter_destroy(&m->i_caps_mis);
err_i_caps_mis:
percpu_counter_destroy(&m->i_caps_hit);
err_i_caps_hit:
percpu_counter_destroy(&m->d_lease_mis);
err_d_lease_mis:
percpu_counter_destroy(&m->d_lease_hit);
return ret;
}
void ceph_metric_destroy(struct ceph_client_metric *m)
{
if (!m)
return;
cancel_delayed_work_sync(&m->delayed_work);
percpu_counter_destroy(&m->total_inodes);
percpu_counter_destroy(&m->opened_inodes);
percpu_counter_destroy(&m->i_caps_mis);
percpu_counter_destroy(&m->i_caps_hit);
percpu_counter_destroy(&m->d_lease_mis);
percpu_counter_destroy(&m->d_lease_hit);
ceph_put_mds_session(m->session);
}
static inline void __update_latency(ktime_t *totalp, ktime_t *lsump,
ktime_t *min, ktime_t *max,
ktime_t *sq_sump, ktime_t lat)
{
ktime_t total, avg, sq, lsum;
total = ++(*totalp);
lsum = (*lsump += lat);
if (unlikely(lat < *min))
*min = lat;
if (unlikely(lat > *max))
*max = lat;
if (unlikely(total == 1))
return;
/* the sq is (lat - old_avg) * (lat - new_avg) */
avg = DIV64_U64_ROUND_CLOSEST((lsum - lat), (total - 1));
sq = lat - avg;
avg = DIV64_U64_ROUND_CLOSEST(lsum, total);
sq = sq * (lat - avg);
*sq_sump += sq;
}
void ceph_update_read_latency(struct ceph_client_metric *m,
ktime_t r_start, ktime_t r_end,
int rc)
{
ktime_t lat = ktime_sub(r_end, r_start);
if (unlikely(rc < 0 && rc != -ENOENT && rc != -ETIMEDOUT))
return;
spin_lock(&m->read_latency_lock);
__update_latency(&m->total_reads, &m->read_latency_sum,
&m->read_latency_min, &m->read_latency_max,
&m->read_latency_sq_sum, lat);
spin_unlock(&m->read_latency_lock);
}
void ceph_update_write_latency(struct ceph_client_metric *m,
ktime_t r_start, ktime_t r_end,
int rc)
{
ktime_t lat = ktime_sub(r_end, r_start);
if (unlikely(rc && rc != -ETIMEDOUT))
return;
spin_lock(&m->write_latency_lock);
__update_latency(&m->total_writes, &m->write_latency_sum,
&m->write_latency_min, &m->write_latency_max,
&m->write_latency_sq_sum, lat);
spin_unlock(&m->write_latency_lock);
}
void ceph_update_metadata_latency(struct ceph_client_metric *m,
ktime_t r_start, ktime_t r_end,
int rc)
{
ktime_t lat = ktime_sub(r_end, r_start);
if (unlikely(rc && rc != -ENOENT))
return;
spin_lock(&m->metadata_latency_lock);
__update_latency(&m->total_metadatas, &m->metadata_latency_sum,
&m->metadata_latency_min, &m->metadata_latency_max,
&m->metadata_latency_sq_sum, lat);
spin_unlock(&m->metadata_latency_lock);
}