| Message ID | 20190206144257.21464-1-harry.pan@intel.com (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Headers | show |
| Series | PM / suspend: measure the time of filesystem syncing | expand |
On Wed, Feb 6, 2019 at 4:57 PM Harry Pan <harry.pan@intel.com> wrote: > > This patch gives the reader an intuitive metric of the time cost by > the kernel issuing a filesystem sync during suspend; 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 > automatic script. > > v2: simplify the variables, apply the simplest form of ktime API. > > Signed-off-by: Harry Pan <harry.pan@intel.com> > --- > kernel/power/suspend.c | 7 ++++++- > 1 file changed, 6 insertions(+), 1 deletion(-) > > diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c > index 0bd595a0b610..87c0073f0c9d 100644 > --- a/kernel/power/suspend.c > +++ b/kernel/power/suspend.c > @@ -550,6 +550,8 @@ static void suspend_finish(void) > static int enter_state(suspend_state_t state) > { > int error; > + ktime_t start; > + unsigned int elapsed_msecs; You only need these two if CONFIG_SUSPEND_SKIP_SYNC is set, -> > > trace_suspend_resume(TPS("suspend_enter"), state, true); > if (state == PM_SUSPEND_TO_IDLE) { > @@ -570,9 +572,12 @@ static int enter_state(suspend_state_t state) > > #ifndef CONFIG_SUSPEND_SKIP_SYNC -> so I would change this to if (IS_ENABLED(CONFIG_SUSPEND_SKIP_SYNC)) { ktime_t start; unsigned int elapsed_msecs; > trace_suspend_resume(TPS("sync_filesystems"), 0, true); > + start = ktime_get(); Why don't you do this after printing the message below? > pr_info("Syncing filesystems ... "); > ksys_sync(); > - pr_cont("done.\n"); > + elapsed_msecs = ktime_to_ms(ktime_sub(ktime_get(), start)); > + pr_cont("(elapsed %d.%03d seconds) done.\n", elapsed_msecs / 1000, > + elapsed_msecs % 1000); Use MSEC_PER_SEC here. > trace_suspend_resume(TPS("sync_filesystems"), 0, false); > #endif >
On Wed, Feb 13, 2019 at 12:21 AM Rafael J. Wysocki <rafael@kernel.org> wrote: > > On Wed, Feb 6, 2019 at 4:57 PM Harry Pan <harry.pan@intel.com> wrote: > > > > This patch gives the reader an intuitive metric of the time cost by > > the kernel issuing a filesystem sync during suspend; 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 > > automatic script. > > > > v2: simplify the variables, apply the simplest form of ktime API. > > > > Signed-off-by: Harry Pan <harry.pan@intel.com> > > --- > > kernel/power/suspend.c | 7 ++++++- > > 1 file changed, 6 insertions(+), 1 deletion(-) > > > > diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c > > index 0bd595a0b610..87c0073f0c9d 100644 > > --- a/kernel/power/suspend.c > > +++ b/kernel/power/suspend.c > > @@ -550,6 +550,8 @@ static void suspend_finish(void) > > static int enter_state(suspend_state_t state) > > { > > int error; > > + ktime_t start; > > + unsigned int elapsed_msecs; > > You only need these two if CONFIG_SUSPEND_SKIP_SYNC is set, -> > > > > > trace_suspend_resume(TPS("suspend_enter"), state, true); > > if (state == PM_SUSPEND_TO_IDLE) { > > @@ -570,9 +572,12 @@ static int enter_state(suspend_state_t state) > > > > #ifndef CONFIG_SUSPEND_SKIP_SYNC > > -> so I would change this to > > if (IS_ENABLED(CONFIG_SUSPEND_SKIP_SYNC)) { if (!IS_ENABLED(CONFIG_SUSPEND_SKIP_SYNC)) { that is (missing "!"). > ktime_t start; > unsigned int elapsed_msecs; > > > trace_suspend_resume(TPS("sync_filesystems"), 0, true); > > + start = ktime_get(); > > Why don't you do this after printing the message below? > > > pr_info("Syncing filesystems ... "); > > ksys_sync(); > > - pr_cont("done.\n"); > > + elapsed_msecs = ktime_to_ms(ktime_sub(ktime_get(), start)); > > + pr_cont("(elapsed %d.%03d seconds) done.\n", elapsed_msecs / 1000, > > + elapsed_msecs % 1000); > > Use MSEC_PER_SEC here. > > > trace_suspend_resume(TPS("sync_filesystems"), 0, false); > > #endif > >
On Wed, Feb 13, 2019 at 12:21 AM Rafael J. Wysocki <rafael@kernel.org> wrote: > > On Wed, Feb 6, 2019 at 4:57 PM Harry Pan <harry.pan@intel.com> wrote: > > > > This patch gives the reader an intuitive metric of the time cost by > > the kernel issuing a filesystem sync during suspend; 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 > > automatic script. > > > > v2: simplify the variables, apply the simplest form of ktime API. > > > > Signed-off-by: Harry Pan <harry.pan@intel.com> > > --- > > kernel/power/suspend.c | 7 ++++++- > > 1 file changed, 6 insertions(+), 1 deletion(-) > > > > diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c > > index 0bd595a0b610..87c0073f0c9d 100644 > > --- a/kernel/power/suspend.c > > +++ b/kernel/power/suspend.c > > @@ -550,6 +550,8 @@ static void suspend_finish(void) > > static int enter_state(suspend_state_t state) > > { > > int error; > > + ktime_t start; > > + unsigned int elapsed_msecs; > > You only need these two if CONFIG_SUSPEND_SKIP_SYNC is set, -> s/set/unset/ Sorry for the confusion.
diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c index 0bd595a0b610..87c0073f0c9d 100644 --- a/kernel/power/suspend.c +++ b/kernel/power/suspend.c @@ -550,6 +550,8 @@ static void suspend_finish(void) static int enter_state(suspend_state_t state) { int error; + ktime_t start; + unsigned int elapsed_msecs; trace_suspend_resume(TPS("suspend_enter"), state, true); if (state == PM_SUSPEND_TO_IDLE) { @@ -570,9 +572,12 @@ static int enter_state(suspend_state_t state) #ifndef CONFIG_SUSPEND_SKIP_SYNC trace_suspend_resume(TPS("sync_filesystems"), 0, true); + start = ktime_get(); pr_info("Syncing filesystems ... "); ksys_sync(); - pr_cont("done.\n"); + elapsed_msecs = ktime_to_ms(ktime_sub(ktime_get(), start)); + pr_cont("(elapsed %d.%03d seconds) done.\n", elapsed_msecs / 1000, + elapsed_msecs % 1000); trace_suspend_resume(TPS("sync_filesystems"), 0, false); #endif
This patch gives the reader an intuitive metric of the time cost by the kernel issuing a filesystem sync during suspend; 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 automatic script. v2: simplify the variables, apply the simplest form of ktime API. Signed-off-by: Harry Pan <harry.pan@intel.com> --- kernel/power/suspend.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)