Commit 7c2ff389 authored by Ingo Molnar's avatar Ingo Molnar Committed by Jens Axboe

blktrace: use cpu_clock() instead of sched_clock()

use cpu_clock() instead of sched_clock(). (the latter is not a proper
clock-source)
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
Signed-off-by: default avatarJens Axboe <jens.axboe@oracle.com>
parent 4d5d8e9d
...@@ -41,7 +41,7 @@ static void trace_note(struct blk_trace *bt, pid_t pid, int action, ...@@ -41,7 +41,7 @@ static void trace_note(struct blk_trace *bt, pid_t pid, int action,
const int cpu = smp_processor_id(); const int cpu = smp_processor_id();
t->magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION; t->magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION;
t->time = sched_clock() - per_cpu(blk_trace_cpu_offset, cpu); t->time = cpu_clock(cpu) - per_cpu(blk_trace_cpu_offset, cpu);
t->device = bt->dev; t->device = bt->dev;
t->action = action; t->action = action;
t->pid = pid; t->pid = pid;
...@@ -159,7 +159,7 @@ void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes, ...@@ -159,7 +159,7 @@ void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes,
t->magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION; t->magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION;
t->sequence = ++(*sequence); t->sequence = ++(*sequence);
t->time = sched_clock() - per_cpu(blk_trace_cpu_offset, cpu); t->time = cpu_clock(cpu) - per_cpu(blk_trace_cpu_offset, cpu);
t->sector = sector; t->sector = sector;
t->bytes = bytes; t->bytes = bytes;
t->action = what; t->action = what;
...@@ -488,17 +488,17 @@ void blk_trace_shutdown(struct request_queue *q) ...@@ -488,17 +488,17 @@ void blk_trace_shutdown(struct request_queue *q)
} }
/* /*
* Average offset over two calls to sched_clock() with a gettimeofday() * Average offset over two calls to cpu_clock() with a gettimeofday()
* in the middle * in the middle
*/ */
static void blk_check_time(unsigned long long *t) static void blk_check_time(unsigned long long *t, int this_cpu)
{ {
unsigned long long a, b; unsigned long long a, b;
struct timeval tv; struct timeval tv;
a = sched_clock(); a = cpu_clock(this_cpu);
do_gettimeofday(&tv); do_gettimeofday(&tv);
b = sched_clock(); b = cpu_clock(this_cpu);
*t = tv.tv_sec * 1000000000 + tv.tv_usec * 1000; *t = tv.tv_sec * 1000000000 + tv.tv_usec * 1000;
*t -= (a + b) / 2; *t -= (a + b) / 2;
...@@ -510,16 +510,16 @@ static void blk_check_time(unsigned long long *t) ...@@ -510,16 +510,16 @@ static void blk_check_time(unsigned long long *t)
static void blk_trace_check_cpu_time(void *data) static void blk_trace_check_cpu_time(void *data)
{ {
unsigned long long *t; unsigned long long *t;
int cpu = get_cpu(); int this_cpu = get_cpu();
t = &per_cpu(blk_trace_cpu_offset, cpu); t = &per_cpu(blk_trace_cpu_offset, this_cpu);
/* /*
* Just call it twice, hopefully the second call will be cache hot * Just call it twice, hopefully the second call will be cache hot
* and a little more precise * and a little more precise
*/ */
blk_check_time(t); blk_check_time(t, this_cpu);
blk_check_time(t); blk_check_time(t, this_cpu);
put_cpu(); put_cpu();
} }
......
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