Revert "Fix comments in StrategyNotifyBgWriter()."

This reverts commit df9e034f958a5cd092f7f461d7a50156f6d076af, which
tried to fix the comments to reflect the change of API of the function
but actually the change had been made only for 9.5 or later.

diff --git a/src/backend/storage/buffer/freelist.c b/src/backend/storage/buffer/freelist.c
index d5bb4db37ee15b62ebf6ac20ff3af169c15a81e9..a07212dc8ec47af73d605dd68668439b7ab6e9f2 100644 (file)
--- a/src/backend/storage/buffer/freelist.c
+++ b/src/backend/storage/buffer/freelist.c
@@ -290,8 +290,8 @@ StrategySyncStart(uint32 *complete_passes, uint32 *num_buf_alloc)
 /*
  * StrategyNotifyBgWriter -- set or clear allocation notification latch
  *
- * If bgwprocno isn't -1, the next invocation of StrategyGetBuffer will
- * set that latch.  Pass -1 to clear the pending notification before it
+ * If bgwriterLatch isn't NULL, the next invocation of StrategyGetBuffer will
+ * set that latch.  Pass NULL to clear the pending notification before it
  * happens.  This feature is used by the bgwriter process to wake itself up
  * from hibernation, and is not meant for anybody else to use.
  */