| Message ID | 1511274984-6165-3-git-send-email-souvik.k.chakravarty@intel.com (mailing list archive) |
|---|---|
| State | Changes Requested, archived |
| Delegated to: | Andy Shevchenko |
| Headers | show |
Hi Souvik,
I love your patch! Perhaps something to improve:
[auto build test WARNING on platform-drivers-x86/for-next]
[also build test WARNING on v4.14 next-20171122]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
url: https://github.com/0day-ci/linux/commits/Souvik-Kumar-Chakravarty/platform-x86-intel_telemetry-Fix-logs-and-formatting/20171123-052155
base: git://git.infradead.org/users/dvhart/linux-platform-drivers-x86.git for-next
config: x86_64-allyesconfig (attached as .config)
compiler: gcc-6 (Debian 6.4.0-9) 6.4.0 20171026
reproduce:
# save the attached .config to linux build tree
make ARCH=x86_64
Note: it may well be a FALSE warning. FWIW you are at least aware of it now.
http://gcc.gnu.org/wiki/Better_Uninitialized_Warnings
All warnings (new ones prefixed by >>):
drivers/platform/x86/intel_telemetry_debugfs.c: In function 'pm_suspend_exit_cb':
>> drivers/platform/x86/intel_telemetry_debugfs.c:915:25: warning: 'suspend_deep_ctr_exit' may be used uninitialized in this function [-Wmaybe-uninitialized]
suspend_deep_ctr_exit++;
~~~~~~~~~~~~~~~~~~~~~^~
>> drivers/platform/x86/intel_telemetry_debugfs.c:912:25: warning: 'suspend_shlw_ctr_exit' may be used uninitialized in this function [-Wmaybe-uninitialized]
suspend_shlw_ctr_exit++;
~~~~~~~~~~~~~~~~~~~~~^~
vim +/suspend_deep_ctr_exit +915 drivers/platform/x86/intel_telemetry_debugfs.c
854
855 static int pm_suspend_exit_cb(void)
856 {
857 struct telemetry_evtlog evtlog[TELEM_MAX_OS_ALLOCATED_EVENTS];
858 struct telemetry_debugfs_conf *conf = debugfs_conf;
859 u32 suspend_shlw_ctr_exit, suspend_deep_ctr_exit;
860 u64 suspend_shlw_res_exit, suspend_deep_res_exit;
861 int ret, index;
862
863 if (!suspend_prep_ok)
864 goto out;
865
866 ret = telemetry_raw_read_eventlog(TELEM_IOSS, evtlog,
867 TELEM_MAX_OS_ALLOCATED_EVENTS);
868 if (ret < 0)
869 goto out;
870
871 for (index = 0; index < ret; index++) {
872 TELEM_CHECK_AND_PARSE_CTRS(conf->s0ix_shlw_occ_id,
873 suspend_shlw_ctr_exit);
874
875 TELEM_CHECK_AND_PARSE_CTRS(conf->s0ix_deep_occ_id,
876 suspend_deep_ctr_exit);
877
878 TELEM_CHECK_AND_PARSE_CTRS(conf->s0ix_shlw_res_id,
879 suspend_shlw_res_exit);
880
881 TELEM_CHECK_AND_PARSE_CTRS(conf->s0ix_deep_res_id,
882 suspend_deep_res_exit);
883 }
884
885 if ((suspend_shlw_ctr_exit < suspend_shlw_ctr_temp) ||
886 (suspend_deep_ctr_exit < suspend_deep_ctr_temp) ||
887 (suspend_shlw_res_exit < suspend_shlw_res_temp) ||
888 (suspend_deep_res_exit < suspend_deep_res_temp)) {
889 pr_err("Wrong s0ix counters detected\n");
890 goto out;
891 }
892
893 /*
894 * Due to some design limitations in the firmware, sometimes the
895 * counters do not get updated by the time we reach here. As a
896 * workaround, we try to see if this was a genuine case of sleep
897 * failure or not by cross-checking from PMC GCR registers directly.
898 */
899 if (suspend_shlw_ctr_exit == suspend_shlw_ctr_temp &&
900 suspend_deep_ctr_exit == suspend_deep_ctr_temp) {
901 ret = intel_pmc_gcr_readq(PMC_GCR_TELEM_SHLW_S0IX_REG,
902 &suspend_shlw_res_exit);
903 if (ret < 0)
904 goto out;
905
906 ret = intel_pmc_gcr_readq(PMC_GCR_TELEM_DEEP_S0IX_REG,
907 &suspend_deep_res_exit);
908 if (ret < 0)
909 goto out;
910
911 if (suspend_shlw_res_exit > suspend_shlw_res_temp)
> 912 suspend_shlw_ctr_exit++;
913
914 if (suspend_deep_res_exit > suspend_deep_res_temp)
> 915 suspend_deep_ctr_exit++;
916 }
917
918 suspend_shlw_ctr_exit -= suspend_shlw_ctr_temp;
919 suspend_deep_ctr_exit -= suspend_deep_ctr_temp;
920 suspend_shlw_res_exit -= suspend_shlw_res_temp;
921 suspend_deep_res_exit -= suspend_deep_res_temp;
922
923 if (suspend_shlw_ctr_exit == 1) {
924 conf->suspend_stats.shlw_ctr +=
925 suspend_shlw_ctr_exit;
926
927 conf->suspend_stats.shlw_res +=
928 suspend_shlw_res_exit;
929 }
930 /* Shallow Wakes Case */
931 else if (suspend_shlw_ctr_exit > 1) {
932 conf->suspend_stats.shlw_swake_ctr +=
933 suspend_shlw_ctr_exit;
934
935 conf->suspend_stats.shlw_swake_res +=
936 suspend_shlw_res_exit;
937 }
938
939 if (suspend_deep_ctr_exit == 1) {
940 conf->suspend_stats.deep_ctr +=
941 suspend_deep_ctr_exit;
942
943 conf->suspend_stats.deep_res +=
944 suspend_deep_res_exit;
945 }
946
947 /* Shallow Wakes Case */
948 else if (suspend_deep_ctr_exit > 1) {
949 conf->suspend_stats.deep_swake_ctr +=
950 suspend_deep_ctr_exit;
951
952 conf->suspend_stats.deep_swake_res +=
953 suspend_deep_res_exit;
954 }
955
956 out:
957 suspend_prep_ok = 0;
958 return NOTIFY_OK;
959 }
960
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
On Tue, Nov 21, 2017 at 4:36 PM, Souvik Kumar Chakravarty <souvik.k.chakravarty@intel.com> wrote: > Suspend stats are not reported consistently due to a limitation in the PMC > firmware. This limitation causes a delay in updating the s0ix counters and > residencies in the telemetry log upon s0ix exit. As a consequence, reading > these counters from the suspend-exit notifier may result in zero read. > > This patch fixes this issue by cross-verifying the s0ix residencies from > the GCR TELEM registers in case the counters are not incremented in the > telemetry log after suspend. > > This fixes https://bugzilla.kernel.org/show_bug.cgi?id=197833 > > We also remove unnecessary 'static' qualifiers from local variables. > > Reported-and-tested-by: Rajneesh Bhardwaj <rajneesh.bhardwaj@intel.com> > Signed-off-by: Souvik Kumar Chakravarty <souvik.k.chakravarty@intel.com> > - static u32 suspend_shlw_ctr_exit, suspend_deep_ctr_exit; > - static u64 suspend_shlw_res_exit, suspend_deep_res_exit; > struct telemetry_debugfs_conf *conf = debugfs_conf; > + u32 suspend_shlw_ctr_exit, suspend_deep_ctr_exit; > + u64 suspend_shlw_res_exit, suspend_deep_res_exit; > int ret, index; > + if (suspend_shlw_ctr_exit == suspend_shlw_ctr_temp && > + suspend_deep_ctr_exit == suspend_deep_ctr_temp) { kbuildbot is absolutely right. How this code is supposed to work? It's flaky. Please, redesign this approach.
On Fri, November 24, 2017 at 2:55 AM, Andy Shevchenko <andy.shevchenko@gmail.com> wrote: > On Tue, Nov 21, 2017 at 4:36 PM, Souvik Kumar Chakravarty > <souvik.k.chakravarty@intel.com> wrote: > > Suspend stats are not reported consistently due to a limitation in the > > PMC firmware. This limitation causes a delay in updating the s0ix > > counters and residencies in the telemetry log upon s0ix exit. As a > > consequence, reading these counters from the suspend-exit notifier may result > in zero read. > > > > This patch fixes this issue by cross-verifying the s0ix residencies > > from the GCR TELEM registers in case the counters are not incremented > > in the telemetry log after suspend. > > > > This fixes https://bugzilla.kernel.org/show_bug.cgi?id=197833 > > > > We also remove unnecessary 'static' qualifiers from local variables. > > > > Reported-and-tested-by: Rajneesh Bhardwaj > > <rajneesh.bhardwaj@intel.com> > > Signed-off-by: Souvik Kumar Chakravarty > > <souvik.k.chakravarty@intel.com> > > > - static u32 suspend_shlw_ctr_exit, suspend_deep_ctr_exit; > > - static u64 suspend_shlw_res_exit, suspend_deep_res_exit; > > struct telemetry_debugfs_conf *conf = debugfs_conf; > > + u32 suspend_shlw_ctr_exit, suspend_deep_ctr_exit; > > + u64 suspend_shlw_res_exit, suspend_deep_res_exit; > > int ret, index; > > > + if (suspend_shlw_ctr_exit == suspend_shlw_ctr_temp && > > + suspend_deep_ctr_exit == suspend_deep_ctr_temp) { > > kbuildbot is absolutely right. How this code is supposed to work? It's flaky. suspend_shlw_ctr_exit & suspend_deep_ctr_exit have already been initialized before this comparison (comparing the counters before and after sleep). I will explicitly initialize them so that kbuildbot does not complain. > > Please, redesign this approach. > > -- > With Best Regards, > Andy Shevchenko
diff --git a/drivers/platform/x86/intel_telemetry_debugfs.c b/drivers/platform/x86/intel_telemetry_debugfs.c index 4249e826..d7e90fd 100644 --- a/drivers/platform/x86/intel_telemetry_debugfs.c +++ b/drivers/platform/x86/intel_telemetry_debugfs.c @@ -855,9 +855,9 @@ static int pm_suspend_prep_cb(void) static int pm_suspend_exit_cb(void) { struct telemetry_evtlog evtlog[TELEM_MAX_OS_ALLOCATED_EVENTS]; - static u32 suspend_shlw_ctr_exit, suspend_deep_ctr_exit; - static u64 suspend_shlw_res_exit, suspend_deep_res_exit; struct telemetry_debugfs_conf *conf = debugfs_conf; + u32 suspend_shlw_ctr_exit, suspend_deep_ctr_exit; + u64 suspend_shlw_res_exit, suspend_deep_res_exit; int ret, index; if (!suspend_prep_ok) @@ -890,6 +890,31 @@ static int pm_suspend_exit_cb(void) goto out; } + /* + * Due to some design limitations in the firmware, sometimes the + * counters do not get updated by the time we reach here. As a + * workaround, we try to see if this was a genuine case of sleep + * failure or not by cross-checking from PMC GCR registers directly. + */ + if (suspend_shlw_ctr_exit == suspend_shlw_ctr_temp && + suspend_deep_ctr_exit == suspend_deep_ctr_temp) { + ret = intel_pmc_gcr_readq(PMC_GCR_TELEM_SHLW_S0IX_REG, + &suspend_shlw_res_exit); + if (ret < 0) + goto out; + + ret = intel_pmc_gcr_readq(PMC_GCR_TELEM_DEEP_S0IX_REG, + &suspend_deep_res_exit); + if (ret < 0) + goto out; + + if (suspend_shlw_res_exit > suspend_shlw_res_temp) + suspend_shlw_ctr_exit++; + + if (suspend_deep_res_exit > suspend_deep_res_temp) + suspend_deep_ctr_exit++; + } + suspend_shlw_ctr_exit -= suspend_shlw_ctr_temp; suspend_deep_ctr_exit -= suspend_deep_ctr_temp; suspend_shlw_res_exit -= suspend_shlw_res_temp;
Suspend stats are not reported consistently due to a limitation in the PMC firmware. This limitation causes a delay in updating the s0ix counters and residencies in the telemetry log upon s0ix exit. As a consequence, reading these counters from the suspend-exit notifier may result in zero read. This patch fixes this issue by cross-verifying the s0ix residencies from the GCR TELEM registers in case the counters are not incremented in the telemetry log after suspend. This fixes https://bugzilla.kernel.org/show_bug.cgi?id=197833 We also remove unnecessary 'static' qualifiers from local variables. Reported-and-tested-by: Rajneesh Bhardwaj <rajneesh.bhardwaj@intel.com> Signed-off-by: Souvik Kumar Chakravarty <souvik.k.chakravarty@intel.com> --- drivers/platform/x86/intel_telemetry_debugfs.c | 29 ++++++++++++++++++++++++-- 1 file changed, 27 insertions(+), 2 deletions(-) Changes since v1: * Use pmc_ipc_gcr_readq API to read 64-bits at a time