diff options
| author | Rusty Russell <rusty@rustcorp.com.au> | 2009-01-17 00:31:15 +0100 |
|---|---|---|
| committer | Mike Travis <travis@sgi.com> | 2009-01-17 00:31:15 +0100 |
| commit | 68564a46976017496c2227660930d81240f82355 (patch) | |
| tree | 22e44be89c3bc3fe3491957cca8bdc92c52e1e38 /kernel | |
| parent | sched: fix warning on ia64 (diff) | |
| download | linux-68564a46976017496c2227660930d81240f82355.tar.xz linux-68564a46976017496c2227660930d81240f82355.zip | |
work_on_cpu: don't try to get_online_cpus() in work_on_cpu.
Impact: remove potential circular lock dependency with cpu hotplug lock
This has caused more problems than it solved, with a pile of cpu
hotplug locking issues.
Followup patches will get_online_cpus() in callers that need it, but
if they don't do it they're no worse than before when they were using
set_cpus_allowed without locking.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/workqueue.c | 14 |
1 files changed, 4 insertions, 10 deletions
diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 2f445833ae37..a35afdbc0161 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -991,8 +991,8 @@ static void do_work_for_cpu(struct work_struct *w) * @fn: the function to run * @arg: the function arg * - * This will return -EINVAL in the cpu is not online, or the return value - * of @fn otherwise. + * This will return the value @fn returns. + * It is up to the caller to ensure that the cpu doesn't go offline. */ long work_on_cpu(unsigned int cpu, long (*fn)(void *), void *arg) { @@ -1001,14 +1001,8 @@ long work_on_cpu(unsigned int cpu, long (*fn)(void *), void *arg) INIT_WORK(&wfc.work, do_work_for_cpu); wfc.fn = fn; wfc.arg = arg; - get_online_cpus(); - if (unlikely(!cpu_online(cpu))) - wfc.ret = -EINVAL; - else { - schedule_work_on(cpu, &wfc.work); - flush_work(&wfc.work); - } - put_online_cpus(); + schedule_work_on(cpu, &wfc.work); + flush_work(&wfc.work); return wfc.ret; } |