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authorLinus Torvalds <torvalds@linux-foundation.org>2014-10-08 05:36:23 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2014-10-08 05:36:23 -0400
commitf8e4fae2e79d2d293fc490ede87be44c9b215d9e (patch)
tree6489b56cf3ccc5e9a1714f0d274349d509475ae9 /arch/tile/kernel/time.c
parent6325e940e7e0c690c6bdfaf5d54309e71845d3d9 (diff)
parent78410af51146796f783925009c8676a30d6c6d90 (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile
Pull arch/tile updates from Chris Metcalf: "The only substantive pieces in this batch are some more vDSO support, and removing the reference to &platform_bus in tile-srom.c. The rest are minor issues reported to me" * git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile: tile: add clock_gettime support to vDSO tile: switch to using seqlocks for the vDSO time code tile gxio: use better string copy primitive char: tile-srom: Add real platform bus parent Removed repeated word in comments tilegx: Enable ARCH_SUPPORTS_ATOMIC_RMW tile: Remove tile-specific _sinitdata and _einitdata tile: use ARRAY_SIZE
Diffstat (limited to 'arch/tile/kernel/time.c')
-rw-r--r--arch/tile/kernel/time.c61
1 files changed, 40 insertions, 21 deletions
diff --git a/arch/tile/kernel/time.c b/arch/tile/kernel/time.c
index d8fbc289e680..c1b362277fb7 100644
--- a/arch/tile/kernel/time.c
+++ b/arch/tile/kernel/time.c
@@ -249,33 +249,52 @@ 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)
{
- struct timespec *wtm = &tk->wall_to_monotonic;
- struct clocksource *clock = tk->tkr.clock;
-
- if (clock != &cycle_counter_cs)
+ if (tk->tkr.clock != &cycle_counter_cs)
return;
- /* Userspace gettimeofday will spin while this value is odd. */
- ++vdso_data->tb_update_count;
- smp_wmb();
- 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;
- vdso_data->wtom_clock_sec = wtm->tv_sec;
- 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_begin(&vdso_data->tb_seq);
+
+ vdso_data->cycle_last = tk->tkr.cycle_last;
+ vdso_data->mask = tk->tkr.mask;
+ vdso_data->mult = tk->tkr.mult;
+ vdso_data->shift = tk->tkr.shift;
+
+ vdso_data->wall_time_sec = tk->xtime_sec;
+ vdso_data->wall_time_snsec = tk->tkr.xtime_nsec;
+
+ vdso_data->monotonic_time_sec = tk->xtime_sec
+ + tk->wall_to_monotonic.tv_sec;
+ vdso_data->monotonic_time_snsec = tk->tkr.xtime_nsec
+ + ((u64)tk->wall_to_monotonic.tv_nsec
+ << tk->tkr.shift);
+ while (vdso_data->monotonic_time_snsec >=
+ (((u64)NSEC_PER_SEC) << tk->tkr.shift)) {
+ vdso_data->monotonic_time_snsec -=
+ ((u64)NSEC_PER_SEC) << tk->tkr.shift;
+ vdso_data->monotonic_time_sec++;
+ }
+
+ vdso_data->wall_time_coarse_sec = tk->xtime_sec;
+ vdso_data->wall_time_coarse_nsec = (long)(tk->tkr.xtime_nsec >>
+ tk->tkr.shift);
+
+ vdso_data->monotonic_time_coarse_sec =
+ vdso_data->wall_time_coarse_sec + tk->wall_to_monotonic.tv_sec;
+ vdso_data->monotonic_time_coarse_nsec =
+ vdso_data->wall_time_coarse_nsec + tk->wall_to_monotonic.tv_nsec;
+
+ while (vdso_data->monotonic_time_coarse_nsec >= NSEC_PER_SEC) {
+ vdso_data->monotonic_time_coarse_nsec -= NSEC_PER_SEC;
+ vdso_data->monotonic_time_coarse_sec++;
+ }
+
+ write_seqcount_end(&vdso_data->tb_seq);
}