lkml.org 
[lkml]   [2018]   [Oct]   [5]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[tip:x86/vdso] x86/vdso: Collapse high resolution functions
Commit-ID:  e9a62f76f93c6f28b6c7e908eb12e5f1313870a2
Gitweb: https://git.kernel.org/tip/e9a62f76f93c6f28b6c7e908eb12e5f1313870a2
Author: Thomas Gleixner <tglx@linutronix.de>
AuthorDate: Mon, 17 Sep 2018 14:45:39 +0200
Committer: Thomas Gleixner <tglx@linutronix.de>
CommitDate: Thu, 4 Oct 2018 23:00:25 +0200

x86/vdso: Collapse high resolution functions

do_realtime() and do_monotonic() are now the same except for the storage
array index. Hand the index in as an argument and collapse the functions.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Matt Rickard <matt@softrans.com.au>
Cc: Stephen Boyd <sboyd@kernel.org>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: devel@linuxdriverproject.org
Cc: virtualization@lists.linux-foundation.org
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Juergen Gross <jgross@suse.com>
Link: https://lkml.kernel.org/r/20180917130707.407955860@linutronix.de

---
arch/x86/entry/vdso/vclock_gettime.c | 35 +++++++----------------------------
1 file changed, 7 insertions(+), 28 deletions(-)

diff --git a/arch/x86/entry/vdso/vclock_gettime.c b/arch/x86/entry/vdso/vclock_gettime.c
index 2c73e7f57316..1351b76638fb 100644
--- a/arch/x86/entry/vdso/vclock_gettime.c
+++ b/arch/x86/entry/vdso/vclock_gettime.c
@@ -205,35 +205,12 @@ notrace static inline u64 vgetsns(int *mode)
return v * gtod->mult;
}

-/* Code size doesn't matter (vdso is 4k anyway) and this is faster. */
-notrace static int __always_inline do_realtime(struct timespec *ts)
+notrace static int do_hres(clockid_t clk, struct timespec *ts)
{
- struct vgtod_ts *base = &gtod->basetime[CLOCK_REALTIME];
+ struct vgtod_ts *base = &gtod->basetime[clk];
unsigned int seq;
- u64 ns;
int mode;
-
- do {
- seq = gtod_read_begin(gtod);
- mode = gtod->vclock_mode;
- ts->tv_sec = base->sec;
- ns = base->nsec;
- ns += vgetsns(&mode);
- ns >>= gtod->shift;
- } while (unlikely(gtod_read_retry(gtod, seq)));
-
- ts->tv_sec += __iter_div_u64_rem(ns, NSEC_PER_SEC, &ns);
- ts->tv_nsec = ns;
-
- return mode;
-}
-
-notrace static int __always_inline do_monotonic(struct timespec *ts)
-{
- struct vgtod_ts *base = &gtod->basetime[CLOCK_MONOTONIC];
- unsigned int seq;
u64 ns;
- int mode;

do {
seq = gtod_read_begin(gtod);
@@ -278,11 +255,11 @@ notrace int __vdso_clock_gettime(clockid_t clock, struct timespec *ts)
{
switch (clock) {
case CLOCK_REALTIME:
- if (do_realtime(ts) == VCLOCK_NONE)
+ if (do_hres(CLOCK_REALTIME, ts) == VCLOCK_NONE)
goto fallback;
break;
case CLOCK_MONOTONIC:
- if (do_monotonic(ts) == VCLOCK_NONE)
+ if (do_hres(CLOCK_MONOTONIC, ts) == VCLOCK_NONE)
goto fallback;
break;
case CLOCK_REALTIME_COARSE:
@@ -305,7 +282,9 @@ int clock_gettime(clockid_t, struct timespec *)
notrace int __vdso_gettimeofday(struct timeval *tv, struct timezone *tz)
{
if (likely(tv != NULL)) {
- if (unlikely(do_realtime((struct timespec *)tv) == VCLOCK_NONE))
+ struct timespec *ts = (struct timespec *) tv;
+
+ if (unlikely(do_hres(CLOCK_REALTIME, ts) == VCLOCK_NONE))
return vdso_fallback_gtod(tv, tz);
tv->tv_usec /= 1000;
}
\
 
 \ /
  Last update: 2018-10-04 23:08    [W:0.138 / U:5.712 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site