Attachment 518927 Details for Bug 731775 – the fix

the fix

0001-dlm_controld-fix-plock-dev_write-no-op.patch (text/plain), 1.65 KB, created by David Teigland on 2011-08-18 19:29:26 UTC

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Creator: David Teigland

Created: 2011-08-18 19:29:26 UTC

Size: 1.65 KB

patch

obsolete

>From 95d90a01d89a610074a4817f1f2cbe67419a7654 Mon Sep 17 00:00:00 2001
>From: David Teigland <teigland@redhat.com>
>Date: Thu, 18 Aug 2011 14:18:04 -0500
>Subject: [PATCH] dlm_controld: fix plock dev_write no op
>
>When a plock unlock is received due to the file
>being closed (the CLOSE flag is set), we should
>not write an unlock result back to the kernel.
>If we do, the kernel, which does not expect a
>reply, will report the error "dev_write no op".
>
>In cases where dlm_controld encounters and error
>handling the unlock operation, it was writing
>the error result back to the kernel, even though
>the unlock was flagged with CLOSE.  The fix is
>to check for the CLOSE flag and skip writing
>the error result, as we do with normal results.
>
>This problem is especially visible when using
>flocks (not plocks).  This is because the kernel
>generates extraneous plock unlock requests
>when files are closed with flocks.  Because
>dlm_controld finds no plocks on the files,
>it replies to the kernel with an error, rather
>than skipping the reply to do CLOSE.
>
>bz 731775
>
>Signed-off-by: David Teigland <teigland@redhat.com>
>---
> group/dlm_controld/plock.c |    6 ++++--
> 1 files changed, 4 insertions(+), 2 deletions(-)
>
>diff --git a/group/dlm_controld/plock.c b/group/dlm_controld/plock.c
>index 6d5dea8..556993b 100644
>--- a/group/dlm_controld/plock.c
>+++ b/group/dlm_controld/plock.c
>@@ -1583,8 +1583,10 @@ void process_plocks(int ci)
> 	return;
> 
>  fail:
>-	info.rv = rv;
>-	rv = write(plock_device_fd, &info, sizeof(info));
>+	if (!(info.flags & DLM_PLOCK_FL_CLOSE)) {
>+		info.rv = rv;
>+		rv = write(plock_device_fd, &info, sizeof(info));
>+	}
> }
> 
> void process_saved_plocks(struct lockspace *ls)
>-- 
>1.7.6
>

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Attachments on bug 731775: 518927