linux_dsm_epyc7002/kernel/time
Paul E. McKenney 803b0ebae9 time: RCU permitted to stop idle entry via softirq
The can_stop_idle_tick() function complains if a softirq vector is
raised too late in the idle-entry process, presumably in order to
prevent dangling softirq invocations from being delayed across the
full idle period, which might be indefinitely long -- and if softirq
was asserted any later than the call to this function, such a delay
might well happen.

However, RCU needs to be able to use softirq to stop idle entry in
order to be able to drain RCU callbacks from the current CPU, which in
turn enables faster entry into dyntick-idle mode, which in turn reduces
power consumption.  Because RCU takes this action at a well-defined
point in the idle-entry path, it is safe for RCU to take this approach.

This commit therefore silences the error message that is sometimes
produced when the going-idle CPU suddenly finds that it has an RCU_SOFTIRQ
to process.  The error message will continue to be issued for other
softirq vectors.

Reported-by: Sedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2012-09-23 07:42:52 -07:00
..
alarmtimer.c alarmtimer: Provide accessor to alarmtimer rtc device 2012-04-20 14:56:36 -07:00
clockevents.c clockevents: Make clockevents_config() a global symbol 2012-05-25 01:44:51 +02:00
clocksource.c kernel-time: fix s/then/than/ spelling errors 2012-03-23 16:49:21 -07:00
jiffies.c time/jiffies: Rename ACTHZ to SHIFTED_HZ 2012-07-31 17:09:12 +02:00
Kconfig timers: Fixup the Kconfig consolidation fallout 2012-05-21 23:43:46 +02:00
Makefile timers: Introduce in-kernel alarm-timer interface 2011-04-26 14:01:44 -07:00
ntp.c time/jiffies: Rename ACTHZ to SHIFTED_HZ 2012-07-31 17:09:12 +02:00
posix-clock.c kernel: Fix files explicitly needing EXPORT_SYMBOL infrastructure 2011-10-31 19:30:05 -04:00
tick-broadcast.c tick: Fix the spurious broadcast timer ticks after resume 2012-04-19 21:27:50 +02:00
tick-common.c clockevents: Make minimum delay adjustments configurable 2011-09-08 11:10:56 +02:00
tick-internal.h clockevents: Make minimum delay adjustments configurable 2011-09-08 11:10:56 +02:00
tick-oneshot.c clockevents: Make minimum delay adjustments configurable 2011-09-08 11:10:56 +02:00
tick-sched.c time: RCU permitted to stop idle entry via softirq 2012-09-23 07:42:52 -07:00
timecompare.c time: Use ARRAY_SIZE macro in timecompare.c 2010-10-21 17:30:06 +02:00
timeconv.c time: add function to convert between calendar time and broken-down time for universal use 2009-09-24 07:20:56 -07:00
timekeeping.c time: Move ktime_t overflow checking into timespec_valid_strict 2012-09-01 10:24:48 -07:00
timer_list.c nohz: Rename ts->idle_tick to ts->last_tick 2012-06-11 20:07:17 +02:00
timer_stats.c locking, timer_stats: Annotate table_lock as raw 2011-09-13 11:12:00 +02:00