Re-add tracking of wait event SLRUFlushSync

SLRUFlushSync has been accidently removed during dee663f, that has moved
the flush of the SLRU files to the checkpointer, so add it back.  The
issue has been noticed by Thomas when checking for orphaned wait
events.

Author: Thomas Munro
Reviewed-by: Bharath Rupireddy
Discussion: https://postgr.es/m/CA+hUKGK6tqm59KuF1z+h5Y8fsWcu5v8+84kduSHwRzwjB2aa_A@mail.gmail.com

diff --git a/src/backend/access/transam/slru.c b/src/backend/access/transam/slru.c
index 5ab86238a92ffe37f8cca58b45a7183fd21afced..2a42f31ec2aa19bb3ad24021535037f341a0ae41 100644 (file)
--- a/src/backend/access/transam/slru.c
+++ b/src/backend/access/transam/slru.c
@@ -1603,7 +1603,9 @@ SlruSyncFileTag(SlruCtl ctl, const FileTag *ftag, char *path)
        if (fd < 0)
                return -1;
 
+       pgstat_report_wait_start(WAIT_EVENT_SLRU_FLUSH_SYNC);
        result = pg_fsync(fd);
+       pgstat_report_wait_end();
        save_errno = errno;
 
        CloseTransientFile(fd);