From: zhong jiang <zhongjiang@huawei.com>
Date: Fri, 26 Oct 2018 15:06:57 -0700
Subject: mm/mempolicy.c: use match_string() helper to simplify the code
Git-commit: dedf2c73b80b4566dfcae8ebe9ed46a38b63a1f9
Patch-mainline: v4.20-rc1
References: git-fixes (mm/mempolicy)

match_string() returns the index of an array for a matching string, which
can be used intead of open coded implementation.

Link: http://lkml.kernel.org/r/1536988365-50310-1-git-send-email-zhongjiang@huawei.com
Signed-off-by: zhong jiang <zhongjiang@huawei.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
---
 mm/mempolicy.c |   11 +++--------
 1 file changed, 3 insertions(+), 8 deletions(-)

--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -2681,12 +2681,11 @@ static const char * const policy_modes[]
 int mpol_parse_str(char *str, struct mempolicy **mpol)
 {
 	struct mempolicy *new = NULL;
-	unsigned short mode;
 	unsigned short mode_flags;
 	nodemask_t nodes;
 	char *nodelist = strchr(str, ':');
 	char *flags = strchr(str, '=');
-	int err = 1;
+	int err = 1, mode;
 
 	if (nodelist) {
 		/* NUL-terminate mode or flags string */
@@ -2701,12 +2700,8 @@ int mpol_parse_str(char *str, struct mem
 	if (flags)
 		*flags++ = '\0';	/* terminate mode string */
 
-	for (mode = 0; mode < MPOL_MAX; mode++) {
-		if (!strcmp(str, policy_modes[mode])) {
-			break;
-		}
-	}
-	if (mode >= MPOL_MAX)
+	mode = match_string(policy_modes, MPOL_MAX, str);
+	if (mode < 0)
 		goto out;
 
 	switch (mode) {