Revert "Fix comments in StrategyNotifyBgWriter()."

This reverts commit a73cc3eff3831d98ea3c6dbeb978b96f1bc72a42, 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 77ffe3483d6d065c56aeb86d7d73afb0acc7e324..4befab0e1ad05f05e950d3dea6f0951d94b4ef4d 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.
  */