Date: Tue, 29 Mar 2022 15:17:02 -0700
From: Nathan Bossart <nathandbossart@gmail.com>
To: pgsql-hackers@postgresql.org
Subject: remove reset_shared()
Message-ID: <20220329221702.GA559657@nathanxps13>
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Hi hackers,

Is there any reason to keep reset_shared() around anymore?  It is now just
a wrapper function for CreateSharedMemoryAndSemaphores(), and AFAICT the
information in the comments is already covered by comments in the shared
memory code.  I think it's arguable that the name of the function makes it
clear that it might recreate the shared memory, but if that is a concern,
perhaps we could rename the function to something like
CreateOrRecreateSharedMemoryAndSemaphores().

I've attached a patch that simply removes this wrapper function.  This is
admittedly just nitpicking, so I don't intend to carry this patch further
if anyone is opposed.

-- 
Nathan Bossart
Amazon Web Services: https://aws.amazon.com

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	filename="v1-0001-Remove-reset_shared.patch"

From 295e1e93a2ff4e655e85040d931c0d332d14b5bd Mon Sep 17 00:00:00 2001
From: Nathan Bossart <nathandbossart@gmail.com>
Date: Tue, 29 Mar 2022 14:56:47 -0700
Subject: [PATCH v1 1/1] Remove reset_shared().

This is now just a wrapper for CreateSharedMemoryAndSemaphores(),
and the information in the comments is already covered by comments
in the shared memory code.
---
 src/backend/postmaster/postmaster.c | 22 ++--------------------
 1 file changed, 2 insertions(+), 20 deletions(-)

diff --git a/src/backend/postmaster/postmaster.c b/src/backend/postmaster/postmaster.c
index 80bb269599..f62d12e74a 100644
--- a/src/backend/postmaster/postmaster.c
+++ b/src/backend/postmaster/postmaster.c
@@ -399,7 +399,6 @@ static void getInstallationPaths(const char *argv0);
 static void checkControlFile(void);
 static Port *ConnCreate(int serverFd);
 static void ConnFree(Port *port);
-static void reset_shared(void);
 static void SIGHUP_handler(SIGNAL_ARGS);
 static void pmdie(SIGNAL_ARGS);
 static void reaper(SIGNAL_ARGS);
@@ -1072,7 +1071,7 @@ PostmasterMain(int argc, char *argv[])
 	/*
 	 * Set up shared memory and semaphores.
 	 */
-	reset_shared();
+	CreateSharedMemoryAndSemaphores();
 
 	/*
 	 * Estimate number of openable files.  This must happen after setting up
@@ -2736,23 +2735,6 @@ InitProcessGlobals(void)
 }
 
 
-/*
- * reset_shared -- reset shared memory and semaphores
- */
-static void
-reset_shared(void)
-{
-	/*
-	 * Create or re-create shared memory and semaphores.
-	 *
-	 * Note: in each "cycle of life" we will normally assign the same IPC keys
-	 * (if using SysV shmem and/or semas).  This helps ensure that we will
-	 * clean up dead IPC objects if the postmaster crashes and is restarted.
-	 */
-	CreateSharedMemoryAndSemaphores();
-}
-
-
 /*
  * SIGHUP -- reread config files, and tell children to do same
  */
@@ -4109,7 +4091,7 @@ PostmasterStateMachine(void)
 		/* re-read control file into local memory */
 		LocalProcessControlFile(true);
 
-		reset_shared();
+		CreateSharedMemoryAndSemaphores();
 
 		StartupPID = StartupDataBase();
 		Assert(StartupPID != 0);
-- 
2.25.1


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