| Message ID | 1472242678-33700-11-git-send-email-lina.iyer@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi Lina,
[auto build test ERROR on pm/linux-next]
[also build test ERROR on v4.8-rc3 next-20160825]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
[Suggest to use git(>=2.9.0) format-patch --base=<commit> (or --base=auto for convenience) to record what (public, well-known) commit your patch series was built on]
[Check https://git-scm.com/docs/git-format-patch for more information]
url: https://github.com/0day-ci/linux/commits/Lina-Iyer/PM-SoC-idle-support-using-PM-domains/20160827-042847
base: https://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm.git linux-next
config: m68k-sun3_defconfig (attached as .config)
compiler: m68k-linux-gcc (GCC) 4.9.0
reproduce:
wget https://git.kernel.org/cgit/linux/kernel/git/wfg/lkp-tests.git/plain/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# save the attached .config to linux build tree
make.cross ARCH=m68k
All errors (new ones prefixed by >>):
In file included from fs/proc/stat.c:13:0:
include/linux/tick.h: In function 'tick_nohz_get_next_wakeup':
>> include/linux/tick.h:138:9: error: 'tick_next_period' undeclared (first use in this function)
return tick_next_period;
^
include/linux/tick.h:138:9: note: each undeclared identifier is reported only once for each function it appears in
vim +/tick_next_period +138 include/linux/tick.h
132
133 return len;
134 }
135
136 static inline ktime_t tick_nohz_get_next_wakeup(int cpu)
137 {
> 138 return tick_next_period;
139 }
140
141 static inline u64 get_cpu_idle_time_us(int cpu, u64 *unused) { return -1; }
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
diff --git a/include/linux/tick.h b/include/linux/tick.h index 62be0786..92fa4b0 100644 --- a/include/linux/tick.h +++ b/include/linux/tick.h @@ -117,6 +117,7 @@ extern void tick_nohz_idle_enter(void); extern void tick_nohz_idle_exit(void); extern void tick_nohz_irq_exit(void); extern ktime_t tick_nohz_get_sleep_length(void); +extern ktime_t tick_nohz_get_next_wakeup(int cpu); extern u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time); extern u64 get_cpu_iowait_time_us(int cpu, u64 *last_update_time); #else /* !CONFIG_NO_HZ_COMMON */ @@ -131,6 +132,12 @@ static inline ktime_t tick_nohz_get_sleep_length(void) return len; } + +static inline ktime_t tick_nohz_get_next_wakeup(int cpu) +{ + return tick_next_period; +} + static inline u64 get_cpu_idle_time_us(int cpu, u64 *unused) { return -1; } static inline u64 get_cpu_iowait_time_us(int cpu, u64 *unused) { return -1; } #endif /* !CONFIG_NO_HZ_COMMON */ diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index 204fdc8..7d8df93 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -990,6 +990,17 @@ ktime_t tick_nohz_get_sleep_length(void) return ts->sleep_length; } +/** + * tick_nohz_get_next_wakeup - return the next wake up of the CPU + */ +ktime_t tick_nohz_get_next_wakeup(int cpu) +{ + struct clock_event_device *dev = + per_cpu(tick_cpu_device.evtdev, cpu); + + return dev->next_event; +} + static void tick_nohz_account_idle_ticks(struct tick_sched *ts) { #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
Knowing the sleep length of the CPU is useful for the power state determination on idle. The value is relative to the time when the call was invoked by the CPU. This doesn't work well when there is a need to know when the actual wakeup is. By reading the next wake up event of a CPU, governors can determine the first CPU to wake up (due to timer) amongst a cluster of CPUs and the sleep time available between the last CPU to idle and the first CPU to resume. This information is useful to determine if the caches and other common hardware blocks can also be put in idle during this common period of inactivity. Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Lina Iyer <lina.iyer@linaro.org> --- include/linux/tick.h | 7 +++++++ kernel/time/tick-sched.c | 11 +++++++++++ 2 files changed, 18 insertions(+)