Commit b04a0f4c authored by Ingo Molnar's avatar Ingo Molnar

sched: add [__]update_rq_clock(rq)

add the [__]update_rq_clock(rq) functions. (No change in functionality,
just reorganization to prepare for elimination of the heavy 64-bit
timestamp-passing in the scheduler.)
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent a4ac01c3
...@@ -318,15 +318,19 @@ static inline int cpu_of(struct rq *rq) ...@@ -318,15 +318,19 @@ static inline int cpu_of(struct rq *rq)
} }
/* /*
* Per-runqueue clock, as finegrained as the platform can give us: * Update the per-runqueue clock, as finegrained as the platform can give
* us, but without assuming monotonicity, etc.:
*/ */
static unsigned long long __rq_clock(struct rq *rq) static void __update_rq_clock(struct rq *rq)
{ {
u64 prev_raw = rq->prev_clock_raw; u64 prev_raw = rq->prev_clock_raw;
u64 now = sched_clock(); u64 now = sched_clock();
s64 delta = now - prev_raw; s64 delta = now - prev_raw;
u64 clock = rq->clock; u64 clock = rq->clock;
#ifdef CONFIG_SCHED_DEBUG
WARN_ON_ONCE(cpu_of(rq) != smp_processor_id());
#endif
/* /*
* Protect against sched_clock() occasionally going backwards: * Protect against sched_clock() occasionally going backwards:
*/ */
...@@ -349,17 +353,24 @@ static unsigned long long __rq_clock(struct rq *rq) ...@@ -349,17 +353,24 @@ static unsigned long long __rq_clock(struct rq *rq)
rq->prev_clock_raw = now; rq->prev_clock_raw = now;
rq->clock = clock; rq->clock = clock;
}
return clock; static void update_rq_clock(struct rq *rq)
{
if (likely(smp_processor_id() == cpu_of(rq)))
__update_rq_clock(rq);
} }
static unsigned long long rq_clock(struct rq *rq) static u64 __rq_clock(struct rq *rq)
{ {
int this_cpu = smp_processor_id(); __update_rq_clock(rq);
if (this_cpu == cpu_of(rq)) return rq->clock;
return __rq_clock(rq); }
static u64 rq_clock(struct rq *rq)
{
update_rq_clock(rq);
return rq->clock; return rq->clock;
} }
...@@ -386,9 +397,12 @@ unsigned long long cpu_clock(int cpu) ...@@ -386,9 +397,12 @@ unsigned long long cpu_clock(int cpu)
{ {
unsigned long long now; unsigned long long now;
unsigned long flags; unsigned long flags;
struct rq *rq;
local_irq_save(flags); local_irq_save(flags);
now = rq_clock(cpu_rq(cpu)); rq = cpu_rq(cpu);
update_rq_clock(rq);
now = rq->clock;
local_irq_restore(flags); local_irq_restore(flags);
return now; return now;
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment