From: Xiubo Li <xiubli@xxxxxxxxxx>
These will be very useful help diagnose problems.
URL: https://tracker.ceph.com/issues/44533
Signed-off-by: Xiubo Li <xiubli@xxxxxxxxxx>
---
Changed in V2:
- switch spin lock to cmpxchg
fs/ceph/debugfs.c | 26 ++++++++++++++++----
fs/ceph/mds_client.c | 9 +++++++
fs/ceph/metric.h | 69 +++++++++++++++++++++++++++++++++++++++++++++++++++-
3 files changed, 98 insertions(+), 6 deletions(-)
diff --git a/fs/ceph/debugfs.c b/fs/ceph/debugfs.c
index 60f3e307..bcf7215 100644
--- a/fs/ceph/debugfs.c
+++ b/fs/ceph/debugfs.c
@@ -130,27 +130,43 @@ static int metric_show(struct seq_file *s, void *p)
struct ceph_mds_client *mdsc = fsc->mdsc;
int i, nr_caps = 0;
s64 total, sum, avg = 0;
+ unsigned long min, max;
- seq_printf(s, "item total sum_lat(us) avg_lat(us)\n");
- seq_printf(s, "-----------------------------------------------------\n");
+ seq_printf(s, "item total sum_lat(us) avg_lat(us) min_lat(us) max_lat(us)\n");
+ seq_printf(s, "-------------------------------------------------------------------------------------\n");
total = percpu_counter_sum(&mdsc->metric.total_reads);
sum = percpu_counter_sum(&mdsc->metric.read_latency_sum);
sum = jiffies_to_usecs(sum);
avg = total ? sum / total : 0;
- seq_printf(s, "%-14s%-12lld%-16lld%lld\n", "read", total, sum, avg);
+ min = atomic_long_read(&mdsc->metric.read_latency_min);
+ min = jiffies_to_usecs(min == ULONG_MAX ? 0 : min);
+ max = atomic_long_read(&mdsc->metric.read_latency_max);
+ max = jiffies_to_usecs(max);
+ seq_printf(s, "%-14s%-12lld%-16lld%-16lld%-16ld%ld\n", "read",
+ total, sum, avg, min, max);
total = percpu_counter_sum(&mdsc->metric.total_writes);
sum = percpu_counter_sum(&mdsc->metric.write_latency_sum);
sum = jiffies_to_usecs(sum);
avg = total ? sum / total : 0;
- seq_printf(s, "%-14s%-12lld%-16lld%lld\n", "write", total, sum, avg);
+ min = atomic_long_read(&mdsc->metric.write_latency_min);
+ min = jiffies_to_usecs(min == ULONG_MAX ? 0 : min);
+ max = atomic_long_read(&mdsc->metric.write_latency_max);
+ max = jiffies_to_usecs(max);
+ seq_printf(s, "%-14s%-12lld%-16lld%-16lld%-16ld%ld\n", "write",
+ total, sum, avg, min, max);
total = percpu_counter_sum(&mdsc->metric.total_metadatas);
sum = percpu_counter_sum(&mdsc->metric.metadata_latency_sum);
sum = jiffies_to_usecs(sum);
avg = total ? sum / total : 0;
- seq_printf(s, "%-14s%-12lld%-16lld%lld\n", "metadata", total, sum, avg);
+ min = atomic_long_read(&mdsc->metric.metadata_latency_min);
+ min = jiffies_to_usecs(min == ULONG_MAX ? 0 : min);
+ max = atomic_long_read(&mdsc->metric.metadata_latency_max);
+ max = jiffies_to_usecs(max);
+ seq_printf(s, "%-14s%-12lld%-16lld%-16lld%-16ld%ld\n", "metadata",
+ total, sum, avg, min, max);
seq_printf(s, "\n");
seq_printf(s, "item total miss hit\n");
diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
index 5c03ed3..7844aa6 100644
--- a/fs/ceph/mds_client.c
+++ b/fs/ceph/mds_client.c
@@ -4358,6 +4358,9 @@ static int ceph_mdsc_metric_init(struct ceph_client_metric *metric)
if (ret)
goto err_read_latency_sum;
+ atomic_long_set(&metric->read_latency_min, ULONG_MAX);
+ atomic_long_set(&metric->read_latency_max, 0);
+
ret = percpu_counter_init(&metric->total_writes, 0, GFP_KERNEL);
if (ret)
goto err_total_writes;
@@ -4366,6 +4369,9 @@ static int ceph_mdsc_metric_init(struct ceph_client_metric *metric)
if (ret)
goto err_write_latency_sum;
+ atomic_long_set(&metric->write_latency_min, ULONG_MAX);
+ atomic_long_set(&metric->write_latency_max, 0);
+
ret = percpu_counter_init(&metric->total_metadatas, 0, GFP_KERNEL);
if (ret)
goto err_total_metadatas;
@@ -4374,6 +4380,9 @@ static int ceph_mdsc_metric_init(struct ceph_client_metric *metric)
if (ret)
goto err_metadata_latency_sum;
+ atomic_long_set(&metric->metadata_latency_min, ULONG_MAX);
+ atomic_long_set(&metric->metadata_latency_max, 0);
+
return 0;
err_metadata_latency_sum:
diff --git a/fs/ceph/metric.h b/fs/ceph/metric.h
index faba142..a399201 100644
--- a/fs/ceph/metric.h
+++ b/fs/ceph/metric.h
@@ -2,6 +2,10 @@
#ifndef _FS_CEPH_MDS_METRIC_H
#define _FS_CEPH_MDS_METRIC_H
+#include <linux/atomic.h>
+#include <linux/percpu.h>
+#include <linux/spinlock.h>
+
/* This is the global metrics */
struct ceph_client_metric {
atomic64_t total_dentries;
@@ -13,12 +17,18 @@ struct ceph_client_metric {
struct percpu_counter total_reads;
struct percpu_counter read_latency_sum;
+ atomic_long_t read_latency_min;
+ atomic_long_t read_latency_max;
struct percpu_counter total_writes;
struct percpu_counter write_latency_sum;
+ atomic_long_t write_latency_min;
+ atomic_long_t write_latency_max;
struct percpu_counter total_metadatas;
struct percpu_counter metadata_latency_sum;
+ atomic_long_t metadata_latency_min;
+ atomic_long_t metadata_latency_max;
};
static inline void ceph_update_cap_hit(struct ceph_client_metric *m)
@@ -36,11 +46,30 @@ static inline void ceph_update_read_latency(struct ceph_client_metric *m,
unsigned long r_end,
int rc)
{
+ unsigned long lat = r_end - r_start;
+ unsigned long cur, old;
+
if (rc < 0 && rc != -ENOENT && rc != -ETIMEDOUT)
return;
percpu_counter_inc(&m->total_reads);
- percpu_counter_add(&m->read_latency_sum, r_end - r_start);
+ percpu_counter_add(&m->read_latency_sum, lat);
+
+ cur = atomic_long_read(&m->read_latency_min);
+ do {
+ old = cur;
+ if (likely(lat > old))
+ break;
+ cur = atomic_long_cmpxchg(&m->read_latency_min, old, lat);
+ } while (cur != old);
+
+ cur = atomic_long_read(&m->read_latency_max);
+ do {
+ old = cur;
+ if (likely(lat < old))
