clocksource: Get rid of cycle_last

cycle_last was added to the clocksource to support the TSC validation. We moved that to the core code, so we can get rid of the extra copy. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
author: Thomas Gleixner <tglx@linutronix.de> 2014-07-16 17:05:13 -0400
committer: John Stultz <john.stultz@linaro.org> 2014-07-23 18:01:52 -0400
commit: 4a0e637738f06673725792d74eed67f8779b62c7 (patch)
tree: a5943ca88cc98cf65d3d2fd22f6311699ed2222b
parent: 09ec54429c6d10f87d1f084de53ae2c1c3a81108 (diff)
10 files changed, 24 insertions, 26 deletions
diff --git a/arch/arm64/kernel/vdso.c b/arch/arm64/kernel/vdso.c
index 50384fec56c4..574672f001f7 100644
--- a/arch/arm64/kernel/vdso.c
+++ b/arch/arm64/kernel/vdso.c
@@ -224,7 +224,7 @@ void update_vsyscall(struct timekeeper *tk)
        vdso_data->wtm_clock_nsec               = tk->wall_to_monotonic.tv_nsec;
        if (!use_syscall) {
-                vdso_data->cs_cycle_last        = tk->clock->cycle_last;
+                vdso_data->cs_cycle_last        = tk->cycle_last;
                vdso_data->xtime_clock_sec      = tk->xtime_sec;
                vdso_data->xtime_clock_nsec     = tk->xtime_nsec;
                vdso_data->cs_mult              = tk->mult;
diff --git a/arch/ia64/kernel/time.c b/arch/ia64/kernel/time.c
index 71c52bc7c28d..11dc42da7daf 100644
--- a/arch/ia64/kernel/time.c
+++ b/arch/ia64/kernel/time.c
@@ -441,7 +441,7 @@ void update_vsyscall_tz(void)
 }
 void update_vsyscall_old(struct timespec *wall, struct timespec *wtm,
-                        struct clocksource *c, u32 mult)
+                         struct clocksource *c, u32 mult, cycles_t cycle_last)
 {
        write_seqcount_begin(&fsyscall_gtod_data.seq);
@@ -450,7 +450,7 @@ void update_vsyscall_old(struct timespec *wall, struct timespec *wtm,
        fsyscall_gtod_data.clk_mult = mult;
        fsyscall_gtod_data.clk_shift = c->shift;
        fsyscall_gtod_data.clk_fsys_mmio = c->archdata.fsys_mmio;
-        fsyscall_gtod_data.clk_cycle_last = c->cycle_last;
+        fsyscall_gtod_data.clk_cycle_last = cycle_last;
        /* copy kernel time structures */
        fsyscall_gtod_data.wall_time.tv_sec = wall->tv_sec;
diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c
index 9fff9cdcc519..368ab374d33c 100644
--- a/arch/powerpc/kernel/time.c
+++ b/arch/powerpc/kernel/time.c
@@ -741,7 +741,7 @@ static cycle_t timebase_read(struct clocksource *cs)
 }
 void update_vsyscall_old(struct timespec *wall_time, struct timespec *wtm,
-                        struct clocksource *clock, u32 mult)
+                         struct clocksource *clock, u32 mult, cycle_t cycle_last)
 {
        u64 new_tb_to_xs, new_stamp_xsec;
        u32 frac_sec;
@@ -774,7 +774,7 @@ void update_vsyscall_old(struct timespec *wall_time, struct timespec *wtm,
         * We expect the caller to have done the first increment of
         * vdso_data->tb_update_count already.
         */
-        vdso_data->tb_orig_stamp = clock->cycle_last;
+        vdso_data->tb_orig_stamp = cycle_last;
        vdso_data->stamp_xsec = new_stamp_xsec;
        vdso_data->tb_to_xs = new_tb_to_xs;
        vdso_data->wtom_clock_sec = wtm->tv_sec;
diff --git a/arch/s390/kernel/time.c b/arch/s390/kernel/time.c
index 0931b110c826..97950f392613 100644
--- a/arch/s390/kernel/time.c
+++ b/arch/s390/kernel/time.c
@@ -220,7 +220,7 @@ void update_vsyscall(struct timekeeper *tk)
        /* Make userspace gettimeofday spin until we're done. */
        ++vdso_data->tb_update_count;
        smp_wmb();
-        vdso_data->xtime_tod_stamp = tk->clock->cycle_last;
+        vdso_data->xtime_tod_stamp = tk->cycle_last;
        vdso_data->xtime_clock_sec = tk->xtime_sec;
        vdso_data->xtime_clock_nsec = tk->xtime_nsec;
        vdso_data->wtom_clock_sec =
diff --git a/arch/tile/kernel/time.c b/arch/tile/kernel/time.c
index ae70155c2f16..d22d5bfc1e4e 100644
--- a/arch/tile/kernel/time.c
+++ b/arch/tile/kernel/time.c
@@ -269,7 +269,7 @@ void update_vsyscall(struct timekeeper *tk)
        /* Userspace gettimeofday will spin while this value is odd. */
        ++vdso_data->tb_update_count;
        smp_wmb();
-        vdso_data->xtime_tod_stamp = clock->cycle_last;
+        vdso_data->xtime_tod_stamp = tk->cycle_last;
        vdso_data->xtime_clock_sec = tk->xtime_sec;
        vdso_data->xtime_clock_nsec = tk->xtime_nsec;
        vdso_data->wtom_clock_sec = wtm->tv_sec;
diff --git a/arch/x86/kernel/vsyscall_gtod.c b/arch/x86/kernel/vsyscall_gtod.c
index 9531fbb123ba..c3cb3c144591 100644
--- a/arch/x86/kernel/vsyscall_gtod.c
+++ b/arch/x86/kernel/vsyscall_gtod.c
@@ -32,7 +32,7 @@ void update_vsyscall(struct timekeeper *tk)
        /* copy vsyscall data */
        vdata->vclock_mode      = tk->clock->archdata.vclock_mode;
-        vdata->cycle_last       = tk->clock->cycle_last;
+        vdata->cycle_last       = tk->cycle_last;
        vdata->mask             = tk->clock->mask;
        vdata->mult             = tk->mult;
        vdata->shift            = tk->shift;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 63832f5110b6..7b25125f3f42 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1001,7 +1001,7 @@ static void update_pvclock_gtod(struct timekeeper *tk)
        /* copy pvclock gtod data */
        vdata->clock.vclock_mode        = tk->clock->archdata.vclock_mode;
-        vdata->clock.cycle_last         = tk->clock->cycle_last;
+        vdata->clock.cycle_last         = tk->cycle_last;
        vdata->clock.mask               = tk->clock->mask;
        vdata->clock.mult               = tk->mult;
        vdata->clock.shift              = tk->shift;
diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h
index a16b497d5159..653f0e2b6ca9 100644
--- a/include/linux/clocksource.h
+++ b/include/linux/clocksource.h
@@ -162,7 +162,6 @@ extern u64 timecounter_cyc2time(struct timecounter *tc,
 * @archdata:           arch-specific data
 * @suspend:            suspend function for the clocksource, if necessary
 * @resume:             resume function for the clocksource, if necessary
- * @cycle_last:         most recent cycle counter value seen by ::read()
 * @owner:              module reference, must be set by clocksource in modules
 */
 struct clocksource {
@@ -171,7 +170,6 @@ struct clocksource {
         * clocksource itself is cacheline aligned.
         */
        cycle_t (*read)(struct clocksource *cs);
-        cycle_t cycle_last;
        cycle_t mask;
        u32 mult;
        u32 shift;
diff --git a/include/linux/timekeeper_internal.h b/include/linux/timekeeper_internal.h
index 2e20275a7083..cb88096222c0 100644
--- a/include/linux/timekeeper_internal.h
+++ b/include/linux/timekeeper_internal.h
@@ -29,6 +29,8 @@
 struct timekeeper {
        /* Current clocksource used for timekeeping. */
        struct clocksource      *clock;
+        /* Last cycle value */
+        cycle_t                 cycle_last;
        /* NTP adjusted clock multiplier */
        u32                     mult;
        /* The shift value of the current clocksource. */
@@ -62,8 +64,6 @@ struct timekeeper {
        /* Number of clock cycles in one NTP interval. */
        cycle_t                 cycle_interval;
-        /* Last cycle value (also stored in clock->cycle_last) */
-        cycle_t                 cycle_last;
        /* Number of clock shifted nano seconds in one NTP interval. */
        u64                     xtime_interval;
        /* shifted nano seconds left over when rounding cycle_interval */
@@ -91,7 +91,8 @@ extern void update_vsyscall_tz(void);
 #elif defined(CONFIG_GENERIC_TIME_VSYSCALL_OLD)
 extern void update_vsyscall_old(struct timespec *ts, struct timespec *wtm,
-                                struct clocksource *c, u32 mult);
+                                struct clocksource *c, u32 mult,
+                                cycles_t cycle_last);
 extern void update_vsyscall_tz(void);
 #else
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index 531805013786..4e748c404749 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -121,7 +121,7 @@ static void tk_setup_internals(struct timekeeper *tk, struct clocksource *clock)
        old_clock = tk->clock;
        tk->clock = clock;
-        tk->cycle_last = clock->cycle_last = clock->read(clock);
+        tk->cycle_last = clock->read(clock);
        /* Do the ns -> cycle conversion first, using original mult */
        tmp = NTP_INTERVAL_LENGTH;
@@ -182,7 +182,7 @@ static inline s64 timekeeping_get_ns(struct timekeeper *tk)
        cycle_now = clock->read(clock);
        /* calculate the delta since the last update_wall_time: */
-        delta = clocksource_delta(cycle_now, clock->cycle_last, clock->mask);
+        delta = clocksource_delta(cycle_now, tk->cycle_last, clock->mask);
        nsec = delta * tk->mult + tk->xtime_nsec;
        nsec >>= tk->shift;
@@ -202,7 +202,7 @@ static inline s64 timekeeping_get_ns_raw(struct timekeeper *tk)
        cycle_now = clock->read(clock);
        /* calculate the delta since the last update_wall_time: */
-        delta = clocksource_delta(cycle_now, clock->cycle_last, clock->mask);
+        delta = clocksource_delta(cycle_now, tk->cycle_last, clock->mask);
        /* convert delta to nanoseconds. */
        nsec = clocksource_cyc2ns(delta, clock->mult, clock->shift);
@@ -218,7 +218,8 @@ static inline void update_vsyscall(struct timekeeper *tk)
        struct timespec xt;
        xt = tk_xtime(tk);
-        update_vsyscall_old(&xt, &tk->wall_to_monotonic, tk->clock, tk->mult);
+        update_vsyscall_old(&xt, &tk->wall_to_monotonic, tk->clock, tk->mult,
+                            tk->cycle_last);
 }
 static inline void old_vsyscall_fixup(struct timekeeper *tk)
@@ -342,8 +343,8 @@ static void timekeeping_forward_now(struct timekeeper *tk)
        clock = tk->clock;
        cycle_now = clock->read(clock);
-        delta = clocksource_delta(cycle_now, clock->cycle_last, clock->mask);
+        delta = clocksource_delta(cycle_now, tk->cycle_last, clock->mask);
-        tk->cycle_last = clock->cycle_last = cycle_now;
+        tk->cycle_last = cycle_now;
        tk->xtime_nsec += delta * tk->mult;
@@ -1020,13 +1021,13 @@ static void timekeeping_resume(void)
         */
        cycle_now = clock->read(clock);
        if ((clock->flags & CLOCK_SOURCE_SUSPEND_NONSTOP) &&
-                cycle_now > clock->cycle_last) {
+                cycle_now > tk->cycle_last) {
                u64 num, max = ULLONG_MAX;
                u32 mult = clock->mult;
                u32 shift = clock->shift;
                s64 nsec = 0;
-                cycle_delta = clocksource_delta(cycle_now, clock->cycle_last,
+                cycle_delta = clocksource_delta(cycle_now, tk->cycle_last,
                                                clock->mask);
                /*
@@ -1053,7 +1054,7 @@ static void timekeeping_resume(void)
                __timekeeping_inject_sleeptime(tk, &ts_delta);
        /* Re-base the last cycle value */
-        tk->cycle_last = clock->cycle_last = cycle_now;
+        tk->cycle_last = cycle_now;
        tk->ntp_error = 0;
        timekeeping_suspended = 0;
        timekeeping_update(tk, TK_MIRROR | TK_CLOCK_WAS_SET);
@@ -1433,7 +1434,7 @@ void update_wall_time(void)
 #ifdef CONFIG_ARCH_USES_GETTIMEOFFSET
        offset = real_tk->cycle_interval;
 #else
-        offset = clocksource_delta(clock->read(clock), clock->cycle_last,
+        offset = clocksource_delta(clock->read(clock), tk->cycle_last,
                                   clock->mask);
 #endif
@@ -1477,8 +1478,6 @@ void update_wall_time(void)
        clock_set |= accumulate_nsecs_to_secs(tk);
        write_seqcount_begin(&tk_core.seq);
-        /* Update clock->cycle_last with the new value */
-        clock->cycle_last = tk->cycle_last;
        /*
         * Update the real timekeeper.
         *
author	Thomas Gleixner <tglx@linutronix.de>	2014-07-16 17:05:13 -0400
committer	John Stultz <john.stultz@linaro.org>	2014-07-23 18:01:52 -0400
commit	4a0e637738f06673725792d74eed67f8779b62c7 (patch)
tree	a5943ca88cc98cf65d3d2fd22f6311699ed2222b
parent	09ec54429c6d10f87d1f084de53ae2c1c3a81108 (diff)