Subject : [BISECTION RESULT] sched: revert cpu_clock to pre-27ec4407790d075c325e1f4da0a19c56953cce23 state Submitter : Nishanth Aravamudan <nacc@us.ibm.com> Date : 2008-08-04 19:46 References : http://marc.info/?l=linux-kernel&m=121787924917646&w=4 Handled-By : Peter Zijlstra <peterz@infradead.org> Patch : http://marc.info/?l=linux-kernel&m=121792660313276&w=4 This entry is being used for tracking a regression from 2.6.26. Please don't close it until the problem is fixed in the mainline.
On Thu, 2008-08-07 at 12:41 -0700, bugme-daemon@bugzilla.kernel.org wrote: > http://bugzilla.kernel.org/show_bug.cgi?id=11269 > > > rjw@sisk.pl changed: > > What |Removed |Added > ---------------------------------------------------------------------------- > CC| |a.p.zijlstra@chello.nl > > > > Subject: sched_clock: delay using sched_clock() Some arch's can't handle sched_clock() being called too early - delay this until sched_clock_init() has been called. Reported-by: Bill Gatliff <bgat@billgatliff.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Tested-by: Nishanth Aravamudan <nacc@us.ibm.com> CC: Russell King - ARM Linux <linux@arm.linux.org.uk> --- include/linux/sched.h | 14 +++----------- kernel/sched_clock.c | 18 ++++++++++++++++-- 2 files changed, 19 insertions(+), 13 deletions(-) Index: linux-2.6/include/linux/sched.h =================================================================== --- linux-2.6.orig/include/linux/sched.h +++ linux-2.6/include/linux/sched.h @@ -1551,16 +1551,10 @@ static inline int set_cpus_allowed(struc extern unsigned long long sched_clock(void); -#ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK -static inline void sched_clock_init(void) -{ -} - -static inline u64 sched_clock_cpu(int cpu) -{ - return sched_clock(); -} +extern void sched_clock_init(void); +extern u64 sched_clock_cpu(int cpu); +#ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK static inline void sched_clock_tick(void) { } @@ -1584,8 +1578,6 @@ static inline void sched_clock_tick_star #endif #else /* CONFIG_HAVE_UNSTABLE_SCHED_CLOCK */ -extern void sched_clock_init(void); -extern u64 sched_clock_cpu(int cpu); extern void sched_clock_tick(void); extern void sched_clock_idle_sleep_event(void); extern void sched_clock_idle_wakeup_event(u64 delta_ns); Index: linux-2.6/kernel/sched_clock.c =================================================================== --- linux-2.6.orig/kernel/sched_clock.c +++ linux-2.6/kernel/sched_clock.c @@ -32,6 +32,7 @@ #include <linux/ktime.h> #include <linux/module.h> +static __read_mostly int sched_clock_running; #ifdef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK @@ -71,8 +72,6 @@ static inline struct sched_clock_data *c return &per_cpu(sched_clock_data, cpu); } -static __read_mostly int sched_clock_running; - void sched_clock_init(void) { u64 ktime_now = ktime_to_ns(ktime_get()); @@ -319,6 +318,21 @@ void sched_clock_idle_wakeup_event(u64 d } EXPORT_SYMBOL_GPL(sched_clock_idle_wakeup_event); +#else /* CONFIG_HAVE_UNSTABLE_SCHED_CLOCK */ + +void sched_clock_init(void) +{ + sched_clock_running = 1; +} + +u64 sched_clock_cpu(int cpu) +{ + if (unlikely(!sched_clock_running)) + return 0; + + return sched_clock(); +} + #endif /*
Ignore-Patch : http://marc.info/?l=linux-kernel&m=121792660313276&w=4 Patch : http://bugzilla.kernel.org/show_bug.cgi?id=11269#c1
fixed by commit c1955a3d4762e7a9bf84035eb3c4886a900f0d15