diff options
author | Chris Metcalf <cmetcalf@tilera.com> | 2014-10-02 10:48:12 -0400 |
---|---|---|
committer | Chris Metcalf <cmetcalf@tilera.com> | 2014-10-02 10:48:12 -0400 |
commit | 94fb1afbcb3e1f8666c9065baded2cb66e72126f (patch) | |
tree | e414f685c7bc7cd88468a0aa834141bec7928e23 /arch/tile/kernel/time.c | |
parent | bceb7efa6a7e656bfaa67b6f54925e7db75bcd52 (diff) | |
download | linux-94fb1afbcb3e1f8666c9065baded2cb66e72126f.tar.bz2 |
tile: switch to using seqlocks for the vDSO time code
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Diffstat (limited to 'arch/tile/kernel/time.c')
-rw-r--r-- | arch/tile/kernel/time.c | 16 |
1 files changed, 6 insertions, 10 deletions
diff --git a/arch/tile/kernel/time.c b/arch/tile/kernel/time.c index d8fbc289e680..2fe8323db77e 100644 --- a/arch/tile/kernel/time.c +++ b/arch/tile/kernel/time.c @@ -249,13 +249,10 @@ cycles_t ns2cycles(unsigned long nsecs) void update_vsyscall_tz(void) { - /* Userspace gettimeofday will spin while this value is odd. */ - ++vdso_data->tz_update_count; - smp_wmb(); + write_seqcount_begin(&vdso_data->tz_seq); vdso_data->tz_minuteswest = sys_tz.tz_minuteswest; vdso_data->tz_dsttime = sys_tz.tz_dsttime; - smp_wmb(); - ++vdso_data->tz_update_count; + write_seqcount_end(&vdso_data->tz_seq); } void update_vsyscall(struct timekeeper *tk) @@ -266,9 +263,8 @@ void update_vsyscall(struct timekeeper *tk) if (clock != &cycle_counter_cs) return; - /* Userspace gettimeofday will spin while this value is odd. */ - ++vdso_data->tb_update_count; - smp_wmb(); + write_seqcount_begin(&vdso_data->tb_seq); + vdso_data->xtime_tod_stamp = tk->tkr.cycle_last; vdso_data->xtime_clock_sec = tk->xtime_sec; vdso_data->xtime_clock_nsec = tk->tkr.xtime_nsec; @@ -276,6 +272,6 @@ void update_vsyscall(struct timekeeper *tk) vdso_data->wtom_clock_nsec = wtm->tv_nsec; vdso_data->mult = tk->tkr.mult; vdso_data->shift = tk->tkr.shift; - smp_wmb(); - ++vdso_data->tb_update_count; + + write_seqcount_end(&vdso_data->tb_seq); } |