shinys000114/linux
1
0
Fork 0
mirror of https://github.com/hardkernel/linux.git synced 2026-06-09 12:17:12 +09:00
Code Issues Packages Projects Releases Wiki Activity

cpuquiet: Remove synchronization from runnables_work_func()

Browse Source 
runnables_stop() can deadlock when cancel_work_sync() waits for the
work function to end and the work function blocks on the same lock
held by runnables_stop().

Removing the locks from runnables_work_func() fixes this. This should
be safe because runnables_lock protects runnables_state and
runnables_work_func() only reads runnables_state. Also, the functions
that change state to DISABLED do a cancel_work_sync() to guarantee the
work function stopped running.

Bug 1215668

Change-Id: I70617b3b0fc81db8555869e67e3b11652af8d94c
Signed-off-by: Peter Boonstoppel <pboonstoppel@nvidia.com>
Reviewed-on: http://git-master/r/193881
Reviewed-by: Mandar Padmawar <mpadmawar@nvidia.com>
Tested-by: Mandar Padmawar <mpadmawar@nvidia.com>
This commit is contained in:
Peter Boonstoppel
2013-01-24 11:04:02 -08:00
committed by Huang, Tao
parent a5ba2c6a79
commit a0529ec18b
1 changed files with 1 additions and 5 deletions
Download Patch File Download Diff File Expand all files Collapse all files

6
drivers/cpuquiet/governors/runnable_threads.c
View File

@@ -183,11 +183,8 @@ static void runnables_work_func(struct work_struct *work)
unsigned int cpu = nr_cpu_ids;
int action;
mutex_lock(&runnables_lock);
if (runnables_state != RUNNING) {
mutex_unlock(&runnables_lock);
if (runnables_state != RUNNING)
return;
}
action = get_action(nr_run_last);
if (action > 0) {
@@ -199,7 +196,6 @@ static void runnables_work_func(struct work_struct *work)
if (cpu < nr_cpu_ids)
cpuquiet_quiesence_cpu(cpu);
}
mutex_unlock(&runnables_lock);
}
CPQ_BASIC_ATTRIBUTE(sample_rate, 0644, uint);