[tip: core/rcu] locktorture: Replace strncmp() with str_has_prefix()

[tip-bot2 for Chuhong Yuan]

The following commit has been merged into the core/rcu branch of tip:

Commit-ID:     c5d3c8ca22d487ad9a18da9a7722a76e9bdbf4fd
Gitweb:        https://git.kernel.org/tip/c5d3c8ca22d487ad9a18da9a7722a76e9bdbf4fd
Author:        Chuhong Yuan <hslester96@xxxxxxxxx>
AuthorDate:    Fri, 02 Aug 2019 09:46:56 +08:00
Committer:     Paul E. McKenney <paulmck@xxxxxxxxxx>
CommitterDate: Sat, 05 Oct 2019 11:48:38 -07:00

locktorture: Replace strncmp() with str_has_prefix()

The strncmp() function is error-prone because it is easy to get the
length wrong, especially if the string is subject to change, especially
given the need to account for the terminating nul byte.  This commit
therefore substitutes the newly introduced str_has_prefix(), which
does not require a separately specified length.

Signed-off-by: Chuhong Yuan <hslester96@xxxxxxxxx>
Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxx>
---
 kernel/locking/locktorture.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/kernel/locking/locktorture.c b/kernel/locking/locktorture.c
index c513031..8dd9002 100644
--- a/kernel/locking/locktorture.c
+++ b/kernel/locking/locktorture.c
@@ -889,16 +889,16 @@ static int __init lock_torture_init(void)
 		cxt.nrealwriters_stress = 2 * num_online_cpus();
 
 #ifdef CONFIG_DEBUG_MUTEXES
-	if (strncmp(torture_type, "mutex", 5) == 0)
+	if (str_has_prefix(torture_type, "mutex"))
 		cxt.debug_lock = true;
 #endif
 #ifdef CONFIG_DEBUG_RT_MUTEXES
-	if (strncmp(torture_type, "rtmutex", 7) == 0)
+	if (str_has_prefix(torture_type, "rtmutex"))
 		cxt.debug_lock = true;
 #endif
 #ifdef CONFIG_DEBUG_SPINLOCK
-	if ((strncmp(torture_type, "spin", 4) == 0) ||
-	    (strncmp(torture_type, "rw_lock", 7) == 0))
+	if ((str_has_prefix(torture_type, "spin")) ||
+	    (str_has_prefix(torture_type, "rw_lock")))
 		cxt.debug_lock = true;
 #endif