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| author | Tina Ruchandani <ruchandani.tina@gmail.com> | 2015-01-28 15:16:11 +0100 |
|---|---|---|
| committer | Steven Rostedt <rostedt@goodmis.org> | 2015-01-28 17:02:05 +0100 |
| commit | da194930ede6d87945786f72b1c36c7a4ed0f3a6 (patch) | |
| tree | 2f80664ea7f783844220d78907bdc17701a69862 /kernel | |
| parent | tracing: Add array printing helper (diff) | |
| download | linux-da194930ede6d87945786f72b1c36c7a4ed0f3a6.tar.xz linux-da194930ede6d87945786f72b1c36c7a4ed0f3a6.zip | |
trace: Use 64-bit timekeeping
The ring_buffer_producer uses 'struct timeval' to measure
its start and end times. 'struct timeval' on 32-bit systems
will have its tv_sec value overflow in year 2038 and beyond.
This patch replaces struct timeval with 'ktime_t' which uses
64-bit representation for nanoseconds.
Link: http://lkml.kernel.org/r/20150128141611.GA2701@tinar
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Tina Ruchandani <ruchandani.tina@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/trace/ring_buffer_benchmark.c | 18 |
1 files changed, 8 insertions, 10 deletions
diff --git a/kernel/trace/ring_buffer_benchmark.c b/kernel/trace/ring_buffer_benchmark.c index 3f9e328c30b5..13d945c0d03f 100644 --- a/kernel/trace/ring_buffer_benchmark.c +++ b/kernel/trace/ring_buffer_benchmark.c @@ -7,7 +7,7 @@ #include <linux/completion.h> #include <linux/kthread.h> #include <linux/module.h> -#include <linux/time.h> +#include <linux/ktime.h> #include <asm/local.h> struct rb_page { @@ -17,7 +17,7 @@ struct rb_page { }; /* run time and sleep time in seconds */ -#define RUN_TIME 10 +#define RUN_TIME 10ULL #define SLEEP_TIME 10 /* number of events for writer to wake up the reader */ @@ -212,8 +212,7 @@ static void ring_buffer_consumer(void) static void ring_buffer_producer(void) { - struct timeval start_tv; - struct timeval end_tv; + ktime_t start_time, end_time, timeout; unsigned long long time; unsigned long long entries; unsigned long long overruns; @@ -227,7 +226,8 @@ static void ring_buffer_producer(void) * make the system stall) */ trace_printk("Starting ring buffer hammer\n"); - do_gettimeofday(&start_tv); + start_time = ktime_get(); + timeout = ktime_add_ns(start_time, RUN_TIME * NSEC_PER_SEC); do { struct ring_buffer_event *event; int *entry; @@ -244,7 +244,7 @@ static void ring_buffer_producer(void) ring_buffer_unlock_commit(buffer, event); } } - do_gettimeofday(&end_tv); + end_time = ktime_get(); cnt++; if (consumer && !(cnt % wakeup_interval)) @@ -264,7 +264,7 @@ static void ring_buffer_producer(void) cond_resched(); #endif - } while (end_tv.tv_sec < (start_tv.tv_sec + RUN_TIME) && !kill_test); + } while (ktime_before(end_time, timeout) && !kill_test); trace_printk("End ring buffer hammer\n"); if (consumer) { @@ -280,9 +280,7 @@ static void ring_buffer_producer(void) wait_for_completion(&read_done); } - time = end_tv.tv_sec - start_tv.tv_sec; - time *= USEC_PER_SEC; - time += (long long)((long)end_tv.tv_usec - (long)start_tv.tv_usec); + time = ktime_us_delta(end_time, start_time); entries = ring_buffer_entries(buffer); overruns = ring_buffer_overruns(buffer); |