1
linux/kernel
Ashok Raj 90d45d17f3 [PATCH] cpu hotplug: fix locking in cpufreq drivers
When calling target drivers to set frequency, we take cpucontrol lock.
When we modified the code to accomodate CPU hotplug, there was an attempt
to take a double lock of cpucontrol leading to a deadlock.  Since the
current thread context is already holding the cpucontrol lock, we dont need
to make another attempt to acquire it.

Now we leave a trace in current->flags indicating current thread already is
under cpucontrol lock held, so we dont attempt to do this another time.

Thanks to Andrew Morton for the beating:-)

From: Brice Goglin <Brice.Goglin@ens-lyon.org>

  Build fix

(akpm: this patch is still unpleasant.  Ashok continues to look for a cleaner
solution, doesn't he?  ;))

Signed-off-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Brice Goglin <Brice.Goglin@ens-lyon.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-09 07:55:50 -08:00
..
irq [PATCH] more kernel-doc cleanups, additions 2005-11-07 07:53:55 -08:00
power [PATCH] swsusp: remove unused variable 2005-11-07 07:53:29 -08:00
acct.c [PATCH] saner handling of auto_acct_off() and DQUOT_OFF() in umount 2005-11-07 18:18:09 -08:00
audit.c [PATCH] gfp_t: kernel/* 2005-10-28 08:16:49 -07:00
auditsc.c [PATCH] gfp_t: kernel/* 2005-10-28 08:16:49 -07:00
capability.c [PATCH] kernel/capability.c: add kerneldoc 2005-07-27 16:26:06 -07:00
compat.c [PATCH] kernel: fix-up schedule_timeout() usage 2005-09-10 10:06:37 -07:00
configs.c Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
cpu.c [PATCH] cpu hotplug: fix locking in cpufreq drivers 2005-11-09 07:55:50 -08:00
cpuset.c [PATCH] cpusets: automatic numa mempolicy rebinding 2005-10-30 17:37:22 -08:00
crash_dump.c [PATCH] kernel/crash_dump.c: add kerneldoc 2005-07-27 16:26:06 -07:00
dma.c Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
exec_domain.c Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
exit.c [PATCH] Process Events Connector 2005-11-07 07:53:35 -08:00
extable.c Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
fork.c [SPARC64] mm: context switch ptlock 2005-11-07 14:09:01 -08:00
futex.c [PATCH] FUTEX_WAKE_OP: enhanced error handling 2005-11-07 07:53:38 -08:00
intermodule.c [PATCH] introduce and use kzalloc 2005-09-07 16:57:45 -07:00
itimer.c [PATCH] itimer fixes 2005-07-27 16:25:51 -07:00
kallsyms.c [PATCH] fix missing includes 2005-10-30 17:37:32 -08:00
Kconfig.hz [PATCH] i386: Selectable Frequency of the Timer Interrupt 2005-06-23 09:45:10 -07:00
Kconfig.preempt [PATCH] sched: voluntary kernel preemption 2005-06-25 16:24:45 -07:00
kexec.c [PATCH] mm: split page table lock 2005-10-29 21:40:42 -07:00
kfifo.c [PATCH] gfp flags annotations - part 1 2005-10-08 15:00:57 -07:00
kmod.c [PATCH] Keys: Get rid of warning in kmod.c if keys disabled 2005-10-30 17:37:23 -08:00
kprobes.c [PATCH] Kprobes: preempt_disable/enable() simplification 2005-11-07 07:53:46 -08:00
ksysfs.c [PATCH] Kdump: Export crash notes section address through sysfs 2005-06-25 16:24:51 -07:00
kthread.c [PATCH] Add kthread_stop_sem() 2005-10-30 17:37:17 -08:00
Makefile [PATCH] RCU torture-testing kernel module 2005-10-30 17:37:27 -08:00
module.c [PATCH] fix remaining missing includes 2005-11-07 07:53:41 -08:00
panic.c [PATCH] Call emergency_reboot from panic 2005-07-26 14:35:43 -07:00
params.c [PATCH] fix missing includes 2005-10-30 17:37:32 -08:00
pid.c Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
posix-cpu-timers.c [PATCH] posix-timers `unlikely' rejig 2005-11-07 07:53:24 -08:00
posix-timers.c [PATCH] posix-timers: use schedule_timeout() in common_nsleep() 2005-10-30 17:37:20 -08:00
printk.c [PATCH] unexport console_unblank 2005-11-07 07:54:07 -08:00
profile.c [PATCH] mostly_read data section 2005-07-07 18:23:46 -07:00
ptrace.c [PATCH] consolidate sys_ptrace() 2005-11-07 07:53:42 -08:00
rcupdate.c [PATCH] RCU torture-testing kernel module 2005-10-30 17:37:27 -08:00
rcutorture.c [PATCH] RCU torture-testing kernel module 2005-10-30 17:37:27 -08:00
resource.c [PATCH] introduce and use kzalloc 2005-09-07 16:57:45 -07:00
sched.c [PATCH] unexport idle_cpu 2005-11-07 07:54:07 -08:00
seccomp.c Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
signal.c [PATCH] Remove duplicate code in signal.c 2005-10-30 17:37:32 -08:00
softirq.c [PATCH] cpu hoptlug: avoid usage of smp_processor_id() in preemptible code 2005-11-07 07:53:29 -08:00
softlockup.c [PATCH] cpu hoptlug: avoid usage of smp_processor_id() in preemptible code 2005-11-07 07:53:29 -08:00
spinlock.c [PATCH] spinlock consolidation 2005-09-10 10:06:21 -07:00
stop_machine.c [PATCH] smp_processor_id() cleanup 2005-06-21 18:46:13 -07:00
sys_ni.c [PATCH] remove sys_set_zone_reclaim() 2005-08-01 10:03:56 -07:00
sys.c [PATCH] unexport uts_sem 2005-11-07 07:54:07 -08:00
sysctl.c [PATCH] Fix sysctl unregistration oops (CVE-2005-2709) 2005-11-08 17:57:30 -08:00
time.c [PATCH] NTP shift_right cleanup 2005-10-30 17:37:18 -08:00
timer.c [PATCH] jiffies_64 cleanup 2005-10-30 17:37:25 -08:00
uid16.c Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
user.c [PATCH] inotify 2005-07-12 20:38:38 -07:00
wait.c Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
workqueue.c [PATCH] cpu hoptlug: avoid usage of smp_processor_id() in preemptible code 2005-11-07 07:53:29 -08:00