linux-kernel - [PATCH] vfs: reduce stack usage in write_cache

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Message-Id: <200804270424.10343.vda.linux@googlemail.com>
Date:	Sun, 27 Apr 2008 04:24:10 +0200
From:	Denys Vlasenko <vda.linux@...glemail.com>
To:	David Chinner <dgc@....com>, Al Viro <viro@...iv.linux.org.uk>
Cc:	xfs@....sgi.com, Eric Sandeen <sandeen@...deen.net>,
	Adrian Bunk <bunk@...nel.org>, linux-kernel@...r.kernel.org,
	linux-fsdevel@...r.kernel.org
Subject: [PATCH] vfs: reduce stack usage in write_cache_pages()

Hi Al, David,

vfs function write_cache_pages() appears on the xfs
writeout path. It's *the* path which causes 4k stack
overflows on i386 with xfs.

This function uses ~100 bytes of stack on 32-bit i386.

This patch transforms it a little so that it uses
a bit less stack - minus 8 bytes to be precise.

This isn't much, but it helps not only xfs,
but all filesystems.

Only compile tested.

Signed-off-by: Denys Vlasenko <vda.linux@...glemail.com>
--
vda

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