Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752468AbaBUFgD (ORCPT ); Fri, 21 Feb 2014 00:36:03 -0500 Received: from mga09.intel.com ([134.134.136.24]:4673 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752241AbaBUFgB (ORCPT ); Fri, 21 Feb 2014 00:36:01 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.97,516,1389772800"; d="scan'208";a="459268731" From: Lan Tianyu To: tj@kernel.org, jolsa@redhat.com, oleg@redhat.com, lenb@kernel.org, rjw@rjwysocki.net Cc: Lan Tianyu , linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] ACPI/Processor: Rework processor throttling with work_on_cpu() Date: Fri, 21 Feb 2014 13:35:45 +0800 Message-Id: <1392960945-30741-1-git-send-email-tianyu.lan@intel.com> X-Mailer: git-send-email 1.8.2.1 In-Reply-To: <20140220151721.GB32719@redhat.com> References: <20140220151721.GB32719@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org acpi_processor_set_throttling() uses set_cpus_allowed_ptr() to make sure struct acpi_processor->acpi_processor_set_throttling() callback run on associated cpu. But the function maybe called in a worker which has been bound to a cpu. The patch is to replace set_cpus_allowed_ptr() with work_on_cpu(). Signed-off-by: Lan Tianyu --- drivers/acpi/processor_throttling.c | 70 +++++++++++++++++-------------------- 1 file changed, 33 insertions(+), 37 deletions(-) diff --git a/drivers/acpi/processor_throttling.c b/drivers/acpi/processor_throttling.c index 28baa05..2db105a 100644 --- a/drivers/acpi/processor_throttling.c +++ b/drivers/acpi/processor_throttling.c @@ -56,6 +56,12 @@ struct throttling_tstate { int target_state; /* target T-state */ }; +struct acpi_processor_throttling_arg { + struct acpi_processor *pr; + int target_state; + bool force; +}; + #define THROTTLING_PRECHANGE (1) #define THROTTLING_POSTCHANGE (2) @@ -1060,16 +1066,25 @@ static int acpi_processor_set_throttling_ptc(struct acpi_processor *pr, return 0; } +static long acpi_processor_throttling_fn(void *data) +{ + struct acpi_processor_throttling_arg *arg = data; + struct acpi_processor *pr = arg->pr; + struct acpi_processor_throttling *p_throttling = &pr->throttling; + + return p_throttling->acpi_processor_set_throttling(pr, + arg->target_state, arg->force); +} + int acpi_processor_set_throttling(struct acpi_processor *pr, int state, bool force) { - cpumask_var_t saved_mask; int ret = 0; unsigned int i; struct acpi_processor *match_pr; struct acpi_processor_throttling *p_throttling; + struct acpi_processor_throttling_arg arg; struct throttling_tstate t_state; - cpumask_var_t online_throttling_cpus; if (!pr) return -EINVAL; @@ -1080,14 +1095,6 @@ int acpi_processor_set_throttling(struct acpi_processor *pr, if ((state < 0) || (state > (pr->throttling.state_count - 1))) return -EINVAL; - if (!alloc_cpumask_var(&saved_mask, GFP_KERNEL)) - return -ENOMEM; - - if (!alloc_cpumask_var(&online_throttling_cpus, GFP_KERNEL)) { - free_cpumask_var(saved_mask); - return -ENOMEM; - } - if (cpu_is_offline(pr->id)) { /* * the cpu pointed by pr->id is offline. Unnecessary to change @@ -1096,17 +1103,15 @@ int acpi_processor_set_throttling(struct acpi_processor *pr, return -ENODEV; } - cpumask_copy(saved_mask, ¤t->cpus_allowed); t_state.target_state = state; p_throttling = &(pr->throttling); - cpumask_and(online_throttling_cpus, cpu_online_mask, - p_throttling->shared_cpu_map); + /* * The throttling notifier will be called for every * affected cpu in order to get one proper T-state. * The notifier event is THROTTLING_PRECHANGE. */ - for_each_cpu(i, online_throttling_cpus) { + for_each_cpu_and(i, cpu_online_mask, p_throttling->shared_cpu_map) { t_state.cpu = i; acpi_processor_throttling_notifier(THROTTLING_PRECHANGE, &t_state); @@ -1118,21 +1123,18 @@ int acpi_processor_set_throttling(struct acpi_processor *pr, * it can be called only for the cpu pointed by pr. */ if (p_throttling->shared_type == DOMAIN_COORD_TYPE_SW_ANY) { - /* FIXME: use work_on_cpu() */ - if (set_cpus_allowed_ptr(current, cpumask_of(pr->id))) { - /* Can't migrate to the pr->id CPU. Exit */ - ret = -ENODEV; - goto exit; - } - ret = p_throttling->acpi_processor_set_throttling(pr, - t_state.target_state, force); + arg.pr = pr; + arg.target_state = state; + arg.force = force; + ret = work_on_cpu(pr->id, acpi_processor_throttling_fn, &arg); } else { /* * When the T-state coordination is SW_ALL or HW_ALL, * it is necessary to set T-state for every affected * cpus. */ - for_each_cpu(i, online_throttling_cpus) { + for_each_cpu_and(i, cpu_online_mask, + p_throttling->shared_cpu_map) { match_pr = per_cpu(processors, i); /* * If the pointer is invalid, we will report the @@ -1153,13 +1155,12 @@ int acpi_processor_set_throttling(struct acpi_processor *pr, "on CPU %d\n", i)); continue; } - t_state.cpu = i; - /* FIXME: use work_on_cpu() */ - if (set_cpus_allowed_ptr(current, cpumask_of(i))) - continue; - ret = match_pr->throttling. - acpi_processor_set_throttling( - match_pr, t_state.target_state, force); + + arg.pr = match_pr; + arg.target_state = state; + arg.force = force; + ret = work_on_cpu(pr->id, acpi_processor_throttling_fn, + &arg); } } /* @@ -1168,17 +1169,12 @@ int acpi_processor_set_throttling(struct acpi_processor *pr, * affected cpu to update the T-states. * The notifier event is THROTTLING_POSTCHANGE */ - for_each_cpu(i, online_throttling_cpus) { + for_each_cpu_and(i, cpu_online_mask, p_throttling->shared_cpu_map) { t_state.cpu = i; acpi_processor_throttling_notifier(THROTTLING_POSTCHANGE, &t_state); } - /* restore the previous state */ - /* FIXME: use work_on_cpu() */ - set_cpus_allowed_ptr(current, saved_mask); -exit: - free_cpumask_var(online_throttling_cpus); - free_cpumask_var(saved_mask); + return ret; } -- 1.8.2.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/