Messages in this thread Patch in this message | | | From | Harry Pan <> | Subject | [PATCH v7 2/2] PM / sleep: measure the time of filesystems syncing | Date | Mon, 25 Feb 2019 17:44:23 +0800 |
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This patch gives the reader an intuitive metric of the time cost by the kernel issuing filesystems sync during system sleep; although developer can guess by the timestamp of next log or enable the ftrace power event for manual calculation, this manner is easier to read and benefits the automation script.
v1 to v5: context discussion v6: split patches logically in code refactor and sync profile v7: improve 32/64 bit machine compatibility
Signed-off-by: Harry Pan <harry.pan@intel.com> --- kernel/power/main.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-)
diff --git a/kernel/power/main.c b/kernel/power/main.c index a8a8e6ec57e6..eea3d65eb960 100644 --- a/kernel/power/main.c +++ b/kernel/power/main.c @@ -54,9 +54,15 @@ EXPORT_SYMBOL_GPL(unlock_system_sleep); void ksys_sync_helper(void) { - pr_info("Syncing filesystems ... "); + ktime_t start; + long elapsed_msecs; + + start = ktime_get(); ksys_sync(); - pr_cont("done.\n"); + elapsed_msecs = ktime_to_ms(ktime_sub(ktime_get(), start)); + pr_info("Filesystems sync: %ld.%03ld seconds\n", + elapsed_msecs / MSEC_PER_SEC, + elapsed_msecs % MSEC_PER_SEC); } EXPORT_SYMBOL_GPL(ksys_sync_helper); -- 2.18.1
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