From mboxrd@z Thu Jan 1 00:00:00 1970 From: Steven Rostedt Subject: [PATCH RT 31/39] thermal: Defer thermal wakups to threads Date: Thu, 12 Mar 2015 15:13:38 -0400 Message-ID: <20150312191412.144062231@goodmis.org> References: <20150312191307.081068717@goodmis.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Cc: Thomas Gleixner , Carsten Emde , Sebastian Andrzej Siewior , John Kacur , Paul Gortmaker , , Daniel Wagner To: linux-kernel@vger.kernel.org, linux-rt-users Return-path: Received: from cdptpa-outbound-snat.email.rr.com ([107.14.166.230]:32518 "EHLO cdptpa-oedge-vip.email.rr.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752591AbbCLTPm (ORCPT ); Thu, 12 Mar 2015 15:15:42 -0400 Content-Disposition: inline; filename=0031-thermal-Defer-thermal-wakups-to-threads.patch Sender: linux-rt-users-owner@vger.kernel.org List-ID: 3.14.34-rt32-rc1 stable review patch. If anyone has any objections, please let me know. ------------------ From: Daniel Wagner On RT the spin lock in pkg_temp_thermal_platfrom_thermal_notify will call schedule while we run in irq context. [] dump_stack+0x4e/0x8f [] __schedule_bug+0xa6/0xb4 [] __schedule+0x5b4/0x700 [] schedule+0x2a/0x90 [] rt_spin_lock_slowlock+0xe5/0x2d0 [] rt_spin_lock+0x25/0x30 [] pkg_temp_thermal_platform_thermal_notify+0x45/0x134 [x86_pkg_temp_thermal] [] ? therm_throt_process+0x1b/0x160 [] intel_thermal_interrupt+0x211/0x250 [] smp_thermal_interrupt+0x21/0x40 [] thermal_interrupt+0x6d/0x80 Let's defer the work to a kthread. Cc: stable-rt@vger.kernel.org Signed-off-by: Daniel Wagner Signed-off-by: Steven Rostedt [bigeasy: reoder init/denit position. TODO: flush swork on exit] Signed-off-by: Sebastian Andrzej Siewior --- drivers/thermal/x86_pkg_temp_thermal.c | 50 ++++++++++++++++++++++++++++++++-- 1 file changed, 47 insertions(+), 3 deletions(-) diff --git a/drivers/thermal/x86_pkg_temp_thermal.c b/drivers/thermal/x86_pkg_temp_thermal.c index 081fd7e6a9f0..f297ddd3365c 100644 --- a/drivers/thermal/x86_pkg_temp_thermal.c +++ b/drivers/thermal/x86_pkg_temp_thermal.c @@ -29,6 +29,7 @@ #include #include #include +#include #include #include @@ -352,7 +353,7 @@ static void pkg_temp_thermal_threshold_work_fn(struct work_struct *work) } } -static int pkg_temp_thermal_platform_thermal_notify(__u64 msr_val) +static void platform_thermal_notify_work(struct swork_event *event) { unsigned long flags; int cpu = smp_processor_id(); @@ -369,7 +370,7 @@ static int pkg_temp_thermal_platform_thermal_notify(__u64 msr_val) pkg_work_scheduled[phy_id]) { disable_pkg_thres_interrupt(); spin_unlock_irqrestore(&pkg_work_lock, flags); - return -EINVAL; + return; } pkg_work_scheduled[phy_id] = 1; spin_unlock_irqrestore(&pkg_work_lock, flags); @@ -378,9 +379,48 @@ static int pkg_temp_thermal_platform_thermal_notify(__u64 msr_val) schedule_delayed_work_on(cpu, &per_cpu(pkg_temp_thermal_threshold_work, cpu), msecs_to_jiffies(notify_delay_ms)); +} + +#ifdef CONFIG_PREEMPT_RT_FULL +static struct swork_event notify_work; + +static int thermal_notify_work_init(void) +{ + int err; + + err = swork_get(); + if (err) + return err; + + INIT_SWORK(¬ify_work, platform_thermal_notify_work); return 0; } +static void thermal_notify_work_cleanup(void) +{ + swork_put(); +} + +static int pkg_temp_thermal_platform_thermal_notify(__u64 msr_val) +{ + swork_queue(¬ify_work); + return 0; +} + +#else /* !CONFIG_PREEMPT_RT_FULL */ + +static int thermal_notify_work_init(void) { return 0; } + +static int thermal_notify_work_cleanup(void) { } + +static int pkg_temp_thermal_platform_thermal_notify(__u64 msr_val) +{ + platform_thermal_notify_work(NULL); + + return 0; +} +#endif /* CONFIG_PREEMPT_RT_FULL */ + static int find_siblings_cpu(int cpu) { int i; @@ -584,6 +624,9 @@ static int __init pkg_temp_thermal_init(void) if (!x86_match_cpu(pkg_temp_thermal_ids)) return -ENODEV; + if (!thermal_notify_work_init()) + return -ENODEV; + spin_lock_init(&pkg_work_lock); platform_thermal_package_notify = pkg_temp_thermal_platform_thermal_notify; @@ -608,7 +651,7 @@ err_ret: kfree(pkg_work_scheduled); platform_thermal_package_notify = NULL; platform_thermal_package_rate_control = NULL;