[tip:x86/vdso] x86, vdso: __vdso_clock_gettime() cleanup

From: tip-bot for Stefani Seibold
Date: Tue Mar 18 2014 - 17:32:25 EST


Commit-ID: ce39c64028a075d14af32bfb8336bfe1370c0443
Gitweb: http://git.kernel.org/tip/ce39c64028a075d14af32bfb8336bfe1370c0443
Author: Stefani Seibold <stefani@xxxxxxxxxxx>
AuthorDate: Mon, 17 Mar 2014 23:22:04 +0100
Committer: H. Peter Anvin <hpa@xxxxxxxxxxxxxxx>
CommitDate: Tue, 18 Mar 2014 12:52:01 -0700

x86, vdso: __vdso_clock_gettime() cleanup

This patch is a small code cleanup for the __vdso_clock_gettime() function.

It removes the unneeded return values from do_monotonic_coarse() and
do_realtime_coarse() and add a fallback label for doing the kernel
gettimeofday() system call.

Reviewed-by: Andy Lutomirski <luto@xxxxxxxxxxxxxx>
Signed-off-by: Stefani Seibold <stefani@xxxxxxxxxxx>
Link: http://lkml.kernel.org/r/1395094933-14252-5-git-send-email-stefani@xxxxxxxxxxx
Signed-off-by: H. Peter Anvin <hpa@xxxxxxxxxxxxxxx>
---
arch/x86/vdso/vclock_gettime.c | 27 ++++++++++++++-------------
1 file changed, 14 insertions(+), 13 deletions(-)

diff --git a/arch/x86/vdso/vclock_gettime.c b/arch/x86/vdso/vclock_gettime.c
index bbc8065..fd074dd 100644
--- a/arch/x86/vdso/vclock_gettime.c
+++ b/arch/x86/vdso/vclock_gettime.c
@@ -209,7 +209,7 @@ notrace static int do_monotonic(struct timespec *ts)
return mode;
}

-notrace static int do_realtime_coarse(struct timespec *ts)
+notrace static void do_realtime_coarse(struct timespec *ts)
{
unsigned long seq;
do {
@@ -217,10 +217,9 @@ notrace static int do_realtime_coarse(struct timespec *ts)
ts->tv_sec = gtod->wall_time_coarse.tv_sec;
ts->tv_nsec = gtod->wall_time_coarse.tv_nsec;
} while (unlikely(read_seqcount_retry(&gtod->seq, seq)));
- return 0;
}

-notrace static int do_monotonic_coarse(struct timespec *ts)
+notrace static void do_monotonic_coarse(struct timespec *ts)
{
unsigned long seq;
do {
@@ -228,30 +227,32 @@ notrace static int do_monotonic_coarse(struct timespec *ts)
ts->tv_sec = gtod->monotonic_time_coarse.tv_sec;
ts->tv_nsec = gtod->monotonic_time_coarse.tv_nsec;
} while (unlikely(read_seqcount_retry(&gtod->seq, seq)));
-
- return 0;
}

notrace int __vdso_clock_gettime(clockid_t clock, struct timespec *ts)
{
- int ret = VCLOCK_NONE;
-
switch (clock) {
case CLOCK_REALTIME:
- ret = do_realtime(ts);
+ if (do_realtime(ts) == VCLOCK_NONE)
+ goto fallback;
break;
case CLOCK_MONOTONIC:
- ret = do_monotonic(ts);
+ if (do_monotonic(ts) == VCLOCK_NONE)
+ goto fallback;
break;
case CLOCK_REALTIME_COARSE:
- return do_realtime_coarse(ts);
+ do_realtime_coarse(ts);
+ break;
case CLOCK_MONOTONIC_COARSE:
- return do_monotonic_coarse(ts);
+ do_monotonic_coarse(ts);
+ break;
+ default:
+ goto fallback;
}

- if (ret == VCLOCK_NONE)
- return vdso_fallback_gettime(clock, ts);
return 0;
+fallback:
+ return vdso_fallback_gettime(clock, ts);
}
int clock_gettime(clockid_t, struct timespec *)
__attribute__((weak, alias("__vdso_clock_gettime")));
--
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