diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2008-01-25 13:42:32 -0800 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2008-01-25 13:42:32 -0800 |
commit | 0008bf54408d4c0637c24d34642f1038c299be95 (patch) | |
tree | 6a14cdacaa3057795381672339737a45e45effc7 /Documentation/cpu-hotplug.txt | |
parent | 2d94dfc8c38edf63e91e48fd55c3a8822b6a9ced (diff) | |
parent | 6d082592b62689fb91578d0338d04a9f50991990 (diff) |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/mingo/linux-2.6-sched
* git://git.kernel.org/pub/scm/linux/kernel/git/mingo/linux-2.6-sched: (96 commits)
sched: keep total / count stats in addition to the max for
sched, futex: detach sched.h and futex.h
sched: fix: don't take a mutex from interrupt context
sched: print backtrace of running tasks too
printk: use ktime_get()
softlockup: fix signedness
sched: latencytop support
sched: fix goto retry in pick_next_task_rt()
timers: don't #error on higher HZ values
sched: monitor clock underflows in /proc/sched_debug
sched: fix rq->clock warps on frequency changes
sched: fix, always create kernel threads with normal priority
debug: clean up kernel/profile.c
sched: remove the !PREEMPT_BKL code
sched: make PREEMPT_BKL the default
debug: track and print last unloaded module in the oops trace
debug: show being-loaded/being-unloaded indicator for modules
sched: rt-watchdog: fix .rlim_max = RLIM_INFINITY
sched: rt-group: reduce rescheduling
hrtimer: unlock hrtimer_wakeup
...
Diffstat (limited to 'Documentation/cpu-hotplug.txt')
-rw-r--r-- | Documentation/cpu-hotplug.txt | 11 |
1 files changed, 6 insertions, 5 deletions
diff --git a/Documentation/cpu-hotplug.txt b/Documentation/cpu-hotplug.txt index a741f658a3c..fb94f5a71b6 100644 --- a/Documentation/cpu-hotplug.txt +++ b/Documentation/cpu-hotplug.txt @@ -109,12 +109,13 @@ Never use anything other than cpumask_t to represent bitmap of CPUs. for_each_cpu_mask(x,mask) - Iterate over some random collection of cpu mask. #include <linux/cpu.h> - lock_cpu_hotplug() and unlock_cpu_hotplug(): + get_online_cpus() and put_online_cpus(): -The above calls are used to inhibit cpu hotplug operations. While holding the -cpucontrol mutex, cpu_online_map will not change. If you merely need to avoid -cpus going away, you could also use preempt_disable() and preempt_enable() -for those sections. Just remember the critical section cannot call any +The above calls are used to inhibit cpu hotplug operations. While the +cpu_hotplug.refcount is non zero, the cpu_online_map will not change. +If you merely need to avoid cpus going away, you could also use +preempt_disable() and preempt_enable() for those sections. +Just remember the critical section cannot call any function that can sleep or schedule this process away. The preempt_disable() will work as long as stop_machine_run() is used to take a cpu down. |