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

diff --git a/arch/x86/entry/vdso/vclock_gettime.c b/arch/x86/entry/vdso/vclock_gettime.c
index 2c73e7f..1351b76 100644 (file)
--- 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;
        }