Commit a0f7bfd3 authored Jul 27, 2009 by Julia Lawall Committed by Felix Blyakher Aug 31, 2009

fs/xfs: Correct redundant test

bp was tested for NULL a few lines before, followed by a return, and there
is no intervening modification of its value.

A simplified version of the semantic match that finds this problem is as
follows: (http://www.emn.fr/x-info/coccinelle/

)

// <smpl>
@r exists@
local idexpression x;
expression E;
position p1,p2;
@@

if (x == NULL || ...) { ... when forall
   return ...; }
... when != \(x=E\|x--\|x++\|--x\|++x\|x-=E\|x+=E\|x|=E\|x&=E\|&x\)
(
*x == NULL
|
*x != NULL
)
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Acked-by: Felix Blyakher <felixb@sgi.com>
Signed-off-by: Felix Blyakher <felixb@sgi.com>

parent eb00457d

fs/xfs/xfs_trans_buf.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -307,7 +307,7 @@ xfs_trans_read_buf(
		return (flags & XFS_BUF_TRYLOCK) ?
		EAGAIN : XFS_ERROR(ENOMEM);

		if ((bp != NULL) && (XFS_BUF_GETERROR(bp) != 0)) {
		if (XFS_BUF_GETERROR(bp) != 0) {
		xfs_ioerror_alert("xfs_trans_read_buf", mp,
		bp, blkno);
		error = XFS_BUF_GETERROR(bp);
		@@ -315,7 +315,7 @@ xfs_trans_read_buf(
		return error;
		}
		#ifdef DEBUG
		if (xfs_do_error && (bp != NULL)) {
		if (xfs_do_error) {
		if (xfs_error_target == target) {
		if (((xfs_req_num++) % xfs_error_mod) == 0) {
		xfs_buf_relse(bp);

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