[patch 06/11] x86/vdso: Collapse high resolution functions

[Thomas Gleixner]

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 <t...@linutronix.de>
---
 arch/x86/entry/vdso/vclock_gettime.c |   35 +++++++----------------------------
 1 file changed, 7 insertions(+), 28 deletions(-)

--- a/arch/x86/entry/vdso/vclock_gettime.c
+++ b/arch/x86/entry/vdso/vclock_gettime.c
@@ -203,35 +203,12 @@ notrace static inline u64 vgetsns(int *m
        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);
@@ -276,11 +253,11 @@ notrace int __vdso_clock_gettime(clockid
 {
        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:
@@ -303,7 +280,9 @@ int clock_gettime(clockid_t, struct time
 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;
        }


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