| Message ID | 1377725085-16798-1-git-send-email-sboyd@codeaurora.org (mailing list archive) |
|---|---|
| State | Accepted, archived |
| Headers | show |
On 29 August 2013 02:54, Stephen Boyd <sboyd@codeaurora.org> wrote: > Workqueues are preemptible even if works are queued on them with > queue_work_on(). Let's use raw_smp_processor_id() here to silence > the warning. > > BUG: using smp_processor_id() in preemptible [00000000] code: kworker/3:2/674 > caller is gov_queue_work+0x28/0xb0 > CPU: 0 PID: 674 Comm: kworker/3:2 Tainted: G W 3.10.0 #30 > Workqueue: events od_dbs_timer > [<c010c178>] (unwind_backtrace+0x0/0x11c) from [<c0109dec>] (show_stack+0x10/0x14) > [<c0109dec>] (show_stack+0x10/0x14) from [<c03885a4>] (debug_smp_processor_id+0xbc/0xf0) > [<c03885a4>] (debug_smp_processor_id+0xbc/0xf0) from [<c0635864>] (gov_queue_work+0x28/0xb0) > [<c0635864>] (gov_queue_work+0x28/0xb0) from [<c0635618>] (od_dbs_timer+0x108/0x134) > [<c0635618>] (od_dbs_timer+0x108/0x134) from [<c01aa8f8>] (process_one_work+0x25c/0x444) > [<c01aa8f8>] (process_one_work+0x25c/0x444) from [<c01aaf88>] (worker_thread+0x200/0x344) > [<c01aaf88>] (worker_thread+0x200/0x344) from [<c01b03bc>] (kthread+0xa0/0xb0) > [<c01b03bc>] (kthread+0xa0/0xb0) from [<c01061b8>] (ret_from_fork+0x14/0x3c) > > Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> > --- > drivers/cpufreq/cpufreq_governor.c | 9 ++++++++- > 1 file changed, 8 insertions(+), 1 deletion(-) Acked-by: Viresh Kumar <viresh.kumar@linaro.org> -- To unsubscribe from this list: send the line "unsubscribe linux-pm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thursday, August 29, 2013 09:50:22 AM Viresh Kumar wrote: > On 29 August 2013 02:54, Stephen Boyd <sboyd@codeaurora.org> wrote: > > Workqueues are preemptible even if works are queued on them with > > queue_work_on(). Let's use raw_smp_processor_id() here to silence > > the warning. > > > > BUG: using smp_processor_id() in preemptible [00000000] code: kworker/3:2/674 > > caller is gov_queue_work+0x28/0xb0 > > CPU: 0 PID: 674 Comm: kworker/3:2 Tainted: G W 3.10.0 #30 > > Workqueue: events od_dbs_timer > > [<c010c178>] (unwind_backtrace+0x0/0x11c) from [<c0109dec>] (show_stack+0x10/0x14) > > [<c0109dec>] (show_stack+0x10/0x14) from [<c03885a4>] (debug_smp_processor_id+0xbc/0xf0) > > [<c03885a4>] (debug_smp_processor_id+0xbc/0xf0) from [<c0635864>] (gov_queue_work+0x28/0xb0) > > [<c0635864>] (gov_queue_work+0x28/0xb0) from [<c0635618>] (od_dbs_timer+0x108/0x134) > > [<c0635618>] (od_dbs_timer+0x108/0x134) from [<c01aa8f8>] (process_one_work+0x25c/0x444) > > [<c01aa8f8>] (process_one_work+0x25c/0x444) from [<c01aaf88>] (worker_thread+0x200/0x344) > > [<c01aaf88>] (worker_thread+0x200/0x344) from [<c01b03bc>] (kthread+0xa0/0xb0) > > [<c01b03bc>] (kthread+0xa0/0xb0) from [<c01061b8>] (ret_from_fork+0x14/0x3c) > > > > Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> > > --- > > drivers/cpufreq/cpufreq_governor.c | 9 ++++++++- > > 1 file changed, 8 insertions(+), 1 deletion(-) > > Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Queued up for 3.12, thanks!
diff --git a/drivers/cpufreq/cpufreq_governor.c b/drivers/cpufreq/cpufreq_governor.c index b9b20fd..bfbcf9a 100644 --- a/drivers/cpufreq/cpufreq_governor.c +++ b/drivers/cpufreq/cpufreq_governor.c @@ -137,7 +137,14 @@ void gov_queue_work(struct dbs_data *dbs_data, struct cpufreq_policy *policy, return; if (!all_cpus) { - __gov_queue_work(smp_processor_id(), dbs_data, delay); + /* + * Use raw_smp_processor_id() to avoid preemptible warnings. + * We know that this is only called with all_cpus == false from + * works that have been queued with *_work_on() functions and + * those works are canceled during CPU_DOWN_PREPARE so they + * can't possibly run on any other CPU. + */ + __gov_queue_work(raw_smp_processor_id(), dbs_data, delay); } else { for_each_cpu(i, policy->cpus) __gov_queue_work(i, dbs_data, delay);
Workqueues are preemptible even if works are queued on them with queue_work_on(). Let's use raw_smp_processor_id() here to silence the warning. BUG: using smp_processor_id() in preemptible [00000000] code: kworker/3:2/674 caller is gov_queue_work+0x28/0xb0 CPU: 0 PID: 674 Comm: kworker/3:2 Tainted: G W 3.10.0 #30 Workqueue: events od_dbs_timer [<c010c178>] (unwind_backtrace+0x0/0x11c) from [<c0109dec>] (show_stack+0x10/0x14) [<c0109dec>] (show_stack+0x10/0x14) from [<c03885a4>] (debug_smp_processor_id+0xbc/0xf0) [<c03885a4>] (debug_smp_processor_id+0xbc/0xf0) from [<c0635864>] (gov_queue_work+0x28/0xb0) [<c0635864>] (gov_queue_work+0x28/0xb0) from [<c0635618>] (od_dbs_timer+0x108/0x134) [<c0635618>] (od_dbs_timer+0x108/0x134) from [<c01aa8f8>] (process_one_work+0x25c/0x444) [<c01aa8f8>] (process_one_work+0x25c/0x444) from [<c01aaf88>] (worker_thread+0x200/0x344) [<c01aaf88>] (worker_thread+0x200/0x344) from [<c01b03bc>] (kthread+0xa0/0xb0) [<c01b03bc>] (kthread+0xa0/0xb0) from [<c01061b8>] (ret_from_fork+0x14/0x3c) Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> --- drivers/cpufreq/cpufreq_governor.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-)