Ping Thanks
-Li > -----邮件原件----- > 发件人: [email protected] > [mailto:[email protected]] 代表 Li RongQing > 发送时间: 2019年10月15日 14:34 > 收件人: [email protected]; [email protected]; > [email protected]; [email protected]; [email protected] > 主题: [PATCH][v2] watchdog/hardlockup: reassign last_timestamp when > enable nmi event > > last_timestamp is not initialized and is zero after boot, or stop to forward > when > nmi watchdog is disabled; and false positives still is possible when restart > NMI > timer after stopping 120 seconds > > so reassign last_timestamp always when enable nmi event > > Fixes: 7edaeb6841df ("kernel/watchdog: Prevent false positives with turbo > modes") > Signed-off-by: Li RongQing <[email protected]> > Signed-off-by: Zhang Yu <[email protected]> > --- > > v1-->v2: make it be able to be compiled on no > v1-->CONFIG_HARDLOCKUP_CHECK_TIMESTAMP platform > > kernel/watchdog_hld.c | 18 +++++++++++++++++- > 1 file changed, 17 insertions(+), 1 deletion(-) > > diff --git a/kernel/watchdog_hld.c b/kernel/watchdog_hld.c index > 247bf0b1582c..f14d18280387 100644 > --- a/kernel/watchdog_hld.c > +++ b/kernel/watchdog_hld.c > @@ -91,11 +91,24 @@ static bool watchdog_check_timestamp(void) > __this_cpu_write(last_timestamp, now); > return true; > } > + > +static void watchdog_touch_timestamp(int cpu) { > + > + ktime_t now = ktime_get_mono_fast_ns(); > + > + per_cpu(last_timestamp, cpu) = now; > +} > #else > static inline bool watchdog_check_timestamp(void) { > return true; > } > + > +static void watchdog_touch_timestamp(int cpu) { > + > +} > #endif > > static struct perf_event_attr wd_hw_attr = { @@ -196,6 +209,7 @@ void > hardlockup_detector_perf_enable(void) > if (!atomic_fetch_inc(&watchdog_cpus)) > pr_info("Enabled. Permanently consumes one hw-PMU counter.\n"); > > + watchdog_touch_timestamp(smp_processor_id()); > perf_event_enable(this_cpu_read(watchdog_ev)); > } > > @@ -274,8 +288,10 @@ void __init hardlockup_detector_perf_restart(void) > for_each_online_cpu(cpu) { > struct perf_event *event = per_cpu(watchdog_ev, cpu); > > - if (event) > + if (event) { > + watchdog_touch_timestamp(cpu); > perf_event_enable(event); > + } > } > } > > -- > 2.16.2
