Commit 5de771e4 authored Mar 22, 2011 by Cesar Eduardo Barros Committed by Linus Torvalds Mar 22, 2011

sys_swapon: move setting of swapfilepages near use



There is no reason I can see to read inode->i_size long before it is
needed. Move its read to just before it is needed, to reduce the
variable lifetime.

Signed-off-by: Cesar Eduardo Barros <cesarb@cesarb.net>
Tested-by: Eric B Munson <emunson@mgebm.net>
Acked-by: Eric B Munson <emunson@mgebm.net>
Reviewed-by: Jesper Juhl <jj@chaosbits.net>
Reviewed-by: Pekka Enberg <penberg@kernel.org>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 87ade72a

mm/swapfile.c

+1 −2

Original line number	Diff line number	Diff line
		@@ -1975,8 +1975,6 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags)
		if (unlikely(error))
		goto bad_swap;

		swapfilepages = i_size_read(inode) >> PAGE_SHIFT;

		/*
		* Read the swap header.
		*/
		@@ -2045,6 +2043,7 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags)
		error = -EINVAL;
		if (!maxpages)
		goto bad_swap;
		swapfilepages = i_size_read(inode) >> PAGE_SHIFT;
		if (swapfilepages && maxpages > swapfilepages) {
		printk(KERN_WARNING
		"Swap area shorter than signature indicates\n");