Fix errno check based on EINTR in pg_flush_data()

Upon a failure of sync_file_range(), EINTR was checked based on the
returned result of the routine rather than its errno.  sync_file_range()
returns -1 on failure, making the check a no-op, invalidating the retry
attempt in this case.

Oversight in 0d369ac65004.

Author: DaeMyung Kang <charsyam@gmail.com>
Discussion: https://postgr.es/m/20260429151811.1810874-1-charsyam@gmail.com
Backpatch-through: 16

diff --git a/src/backend/storage/file/fd.c b/src/backend/storage/file/fd.c
index b54c42d9f84991c2ce4aa0aae4461c91b8c05aab..bf331867457bf218a8084edb6e70fb6dcb7ad2c4 100644 (file)
--- a/src/backend/storage/file/fd.c
+++ b/src/backend/storage/file/fd.c
@@ -516,7 +516,7 @@ retry:
                {
                        int                     elevel;
 
-                       if (rc == EINTR)
+                       if (errno == EINTR)
                                goto retry;
 
                        /*