diff options
author | Michael Paquier <michael@paquier.xyz> | 2025-09-30 09:02:09 +0900 |
---|---|---|
committer | Michael Paquier <michael@paquier.xyz> | 2025-09-30 09:02:09 +0900 |
commit | 3cc689f833b1c9c5b52f1fe07c0e0fd817e23c8b (patch) | |
tree | 60be5d65abae88b3ee5dbee86a6667b8cd5f275e | |
parent | ef38a4d9756db9ae1d20f40aa39f3cf76059b81a (diff) |
injection_points: Add proper locking when reporting fixed-variable stats
Contrary to its siblings for the archiver, the bgwriter and the
checkpointer stats, pgstat_report_inj_fixed() can be called
concurrently. This was causing an assertion failure, while messing up
with the stats.
This code is aimed at being a template for extension developers, so it
is not a critical issue, but let's be correct. This module has also
been useful for some benchmarking, at least for me, and that was how I
have discovered this issue.
Oversight in f68cd847fa40.
Author: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Reviewed-by: Chao Li <li.evan.chao@gmail.com>
Reviewed-by: wenhui qiu <qiuwenhuifx@gmail.com>
Discussion: https://postgr.es/m/aNnXbAXHPFUWPIz2@paquier.xyz
Backpatch-through: 18
-rw-r--r-- | src/test/modules/injection_points/injection_stats_fixed.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/src/test/modules/injection_points/injection_stats_fixed.c b/src/test/modules/injection_points/injection_stats_fixed.c index bc54c79d190..74c35fcbfa7 100644 --- a/src/test/modules/injection_points/injection_stats_fixed.c +++ b/src/test/modules/injection_points/injection_stats_fixed.c @@ -152,6 +152,8 @@ pgstat_report_inj_fixed(uint32 numattach, stats_shmem = pgstat_get_custom_shmem_data(PGSTAT_KIND_INJECTION_FIXED); + LWLockAcquire(&stats_shmem->lock, LW_EXCLUSIVE); + pgstat_begin_changecount_write(&stats_shmem->changecount); stats_shmem->stats.numattach += numattach; stats_shmem->stats.numdetach += numdetach; @@ -159,6 +161,8 @@ pgstat_report_inj_fixed(uint32 numattach, stats_shmem->stats.numcached += numcached; stats_shmem->stats.numloaded += numloaded; pgstat_end_changecount_write(&stats_shmem->changecount); + + LWLockRelease(&stats_shmem->lock); } /* |