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x86/vdso: Collapse high resolution functions

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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
This commit is contained in:
Thomas Gleixner 2018-09-17 14:45:39 +02:00
parent 49116f2081
commit e9a62f76f9
1 changed files with 7 additions and 28 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

35
arch/x86/entry/vdso/vclock_gettime.c
View file

@ -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;
}