@@ -1223,14 +1223,7 @@ static int powernowk8_target(struct cpufreq_policy *pol,
struct powernowk8_target_arg pta = { .pol = pol, .targfreq = targfreq,
.relation = relation };
- /*
- * Must run on @pol->cpu. cpufreq core is responsible for ensuring
- * that we're bound to the current CPU and pol->cpu stays online.
- */
- if (smp_processor_id() == pol->cpu)
- return powernowk8_target_fn(&pta);
- else
- return work_on_cpu(pol->cpu, powernowk8_target_fn, &pta);
+ return work_on_cpu(pol->cpu, powernowk8_target_fn, &pta);
}
/* Driver entry point to verify the policy and range of frequencies */
This is a note to let you know that I have just added a patch titled cpufreq / powernow-k8: Remove usage of smp_processor_id() in to the linux-3.5.y-queue branch of the 3.5.yuz extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.5.y-queue If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.5.yuz tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Herton ------ From 83a5958c6333dfafe31e9eefe91a7f18effaff62 Mon Sep 17 00:00:00 2001 From: Andreas Herrmann <andreas.herrmann3@amd.com> Date: Tue, 23 Oct 2012 00:55:10 +0200 Subject: [PATCH] cpufreq / powernow-k8: Remove usage of smp_processor_id() in preemptible code commit e4df1cbcc1f329e53a1fff7450b2229e0addff20 upstream. Commit 6889125b8b4e09c5e53e6ecab3433bed1ce198c9 (cpufreq/powernow-k8: workqueue user shouldn't migrate the kworker to another CPU) causes powernow-k8 to trigger a preempt warning, e.g.: BUG: using smp_processor_id() in preemptible [00000000] code: cpufreq/3776 caller is powernowk8_target+0x20/0x49 Pid: 3776, comm: cpufreq Not tainted 3.6.0 #9 Call Trace: [<ffffffff8125b447>] debug_smp_processor_id+0xc7/0xe0 [<ffffffff814877e7>] powernowk8_target+0x20/0x49 [<ffffffff81482b02>] __cpufreq_driver_target+0x82/0x8a [<ffffffff81484fc6>] cpufreq_governor_performance+0x4e/0x54 [<ffffffff81482c50>] __cpufreq_governor+0x8c/0xc9 [<ffffffff81482e6f>] __cpufreq_set_policy+0x1a9/0x21e [<ffffffff814839af>] store_scaling_governor+0x16f/0x19b [<ffffffff81484f16>] ? cpufreq_update_policy+0x124/0x124 [<ffffffff8162b4a5>] ? _raw_spin_unlock_irqrestore+0x2c/0x49 [<ffffffff81483640>] store+0x60/0x88 [<ffffffff811708c0>] sysfs_write_file+0xf4/0x130 [<ffffffff8111243b>] vfs_write+0xb5/0x151 [<ffffffff811126e0>] sys_write+0x4a/0x71 [<ffffffff816319a9>] system_call_fastpath+0x16/0x1b Fix this by by always using work_on_cpu(). Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com> --- drivers/cpufreq/powernow-k8.c | 9 +-------- 1 file changed, 1 insertion(+), 8 deletions(-) -- 1.7.9.5