From 22e580d07f6529a395c129575127ea6d860aed3a Mon Sep 17 00:00:00 2001 From: Bockholdt Arne Date: Tue, 26 Nov 2013 07:13:57 +0000 Subject: [PATCH 1/4] intel_idle: Fixed C6 state on Avoton/Rangeley processors Corrected the MWAIT flag for C-State C6 on Intel Avoton/Rangeley processors. Signed-off-by: Arne Bockholdt Acked-by: Len Brown Signed-off-by: Rafael J. Wysocki --- drivers/idle/intel_idle.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c index cbd4e9abc47e..92d1206482a6 100644 --- a/drivers/idle/intel_idle.c +++ b/drivers/idle/intel_idle.c @@ -329,7 +329,7 @@ static struct cpuidle_state atom_cstates[] __initdata = { { .enter = NULL } }; -static struct cpuidle_state avn_cstates[CPUIDLE_STATE_MAX] = { +static struct cpuidle_state avn_cstates[] __initdata = { { .name = "C1-AVN", .desc = "MWAIT 0x00", @@ -340,7 +340,7 @@ static struct cpuidle_state avn_cstates[CPUIDLE_STATE_MAX] = { { .name = "C6-AVN", .desc = "MWAIT 0x51", - .flags = MWAIT2flg(0x58) | CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED, + .flags = MWAIT2flg(0x51) | CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 15, .target_residency = 45, .enter = &intel_idle }, From 5a87182aa21d6d5d306840feab9321818dd3e2a3 Mon Sep 17 00:00:00 2001 From: Viresh Kumar Date: Wed, 27 Nov 2013 09:09:42 +0530 Subject: [PATCH 2/4] cpufreq: suspend governors on system suspend/hibernate This patch adds cpufreq suspend/resume calls to dpm_{suspend|resume}_noirq() for handling suspend/resume of cpufreq governors. Lan Tianyu (Intel) & Jinhyuk Choi (Broadcom) found anr issue where tunables configuration for clusters/sockets with non-boot CPUs was getting lost after suspend/resume, as we were notifying governors with CPUFREQ_GOV_POLICY_EXIT on removal of the last cpu for that policy and so deallocating memory for tunables. This is fixed by this patch as we don't allow any operation on governors after device suspend and before device resume now. Reported-and-tested-by: Lan Tianyu Reported-by: Jinhyuk Choi Signed-off-by: Viresh Kumar [rjw: Changelog, minor cleanups] Signed-off-by: Rafael J. Wysocki --- drivers/base/power/main.c | 3 +++ drivers/cpufreq/cpufreq.c | 43 +++++++++++++++++++++++++++++++++++++++ include/linux/cpufreq.h | 8 ++++++++ 3 files changed, 54 insertions(+) diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c index 9f098a82cf04..10c3510d72a9 100644 --- a/drivers/base/power/main.c +++ b/drivers/base/power/main.c @@ -29,6 +29,7 @@ #include #include #include +#include #include #include "../base.h" #include "power.h" @@ -473,6 +474,7 @@ static void dpm_resume_noirq(pm_message_t state) dpm_show_time(starttime, state, "noirq"); resume_device_irqs(); cpuidle_resume(); + cpufreq_resume(); } /** @@ -885,6 +887,7 @@ static int dpm_suspend_noirq(pm_message_t state) ktime_t starttime = ktime_get(); int error = 0; + cpufreq_suspend(); cpuidle_pause(); suspend_device_irqs(); mutex_lock(&dpm_list_mtx); diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index 02d534da22dd..606224a8abc2 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -26,6 +26,7 @@ #include #include #include +#include #include #include #include @@ -47,6 +48,9 @@ static LIST_HEAD(cpufreq_policy_list); static DEFINE_PER_CPU(char[CPUFREQ_NAME_LEN], cpufreq_cpu_governor); #endif +/* Flag to suspend/resume CPUFreq governors */ +static bool cpufreq_suspended; + static inline bool has_target(void) { return cpufreq_driver->target_index || cpufreq_driver->target; @@ -1462,6 +1466,41 @@ static struct subsys_interface cpufreq_interface = { .remove_dev = cpufreq_remove_dev, }; +void cpufreq_suspend(void) +{ + struct cpufreq_policy *policy; + + if (!has_target()) + return; + + pr_debug("%s: Suspending Governors\n", __func__); + + list_for_each_entry(policy, &cpufreq_policy_list, policy_list) + if (__cpufreq_governor(policy, CPUFREQ_GOV_STOP)) + pr_err("%s: Failed to stop governor for policy: %p\n", + __func__, policy); + + cpufreq_suspended = true; +} + +void cpufreq_resume(void) +{ + struct cpufreq_policy *policy; + + if (!has_target()) + return; + + pr_debug("%s: Resuming Governors\n", __func__); + + cpufreq_suspended = false; + + list_for_each_entry(policy, &cpufreq_policy_list, policy_list) + if (__cpufreq_governor(policy, CPUFREQ_GOV_START) + || __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS)) + pr_err("%s: Failed to start governor for policy: %p\n", + __func__, policy); +} + /** * cpufreq_bp_suspend - Prepare the boot CPU for system suspend. * @@ -1764,6 +1803,10 @@ static int __cpufreq_governor(struct cpufreq_policy *policy, struct cpufreq_governor *gov = NULL; #endif + /* Don't start any governor operations if we are entering suspend */ + if (cpufreq_suspended) + return 0; + if (policy->governor->max_transition_latency && policy->cpuinfo.transition_latency > policy->governor->max_transition_latency) { diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h index 5bd6ab9b0c27..91716658e9a1 100644 --- a/include/linux/cpufreq.h +++ b/include/linux/cpufreq.h @@ -272,6 +272,14 @@ cpufreq_verify_within_cpu_limits(struct cpufreq_policy *policy) policy->cpuinfo.max_freq); } +#ifdef CONFIG_CPU_FREQ +void cpufreq_suspend(void); +void cpufreq_resume(void); +#else +static inline void cpufreq_suspend(void) {} +static inline void cpufreq_resume(void) {} +#endif + /********************************************************************* * CPUFREQ NOTIFIER INTERFACE * *********************************************************************/ From 2167e2399dc5e69c62db56d933e9c8cbe107620a Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Bj=C3=B8rn=20Mork?= Date: Tue, 3 Dec 2013 12:14:32 +0100 Subject: [PATCH 3/4] cpufreq: fix garbage kobjects on errors during suspend/resume MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This is effectively a revert of commit 5302c3fb2e62 ("cpufreq: Perform light-weight init/teardown during suspend/resume"), which enabled suspend/resume optimizations leaving the sysfs files in place. Errors during suspend/resume are not handled properly, leaving dead sysfs attributes in case of failures. There are are number of functions with special code for the "frozen" case, and all these need to also have special error handling. The problem is easy to demonstrate by making cpufreq_driver->init() or cpufreq_driver->get() fail during resume. The code is too complex for a simple fix, with split code paths in multiple blocks within a number of functions. It is therefore best to revert the patch enabling this code until the error handling is in place. Examples of problems resulting from resume errors: WARNING: CPU: 0 PID: 6055 at fs/sysfs/file.c:343 sysfs_open_file+0x77/0x212() missing sysfs attribute operations for kobject: (null) Modules linked in: [stripped as irrelevant] CPU: 0 PID: 6055 Comm: grep Tainted: G D 3.13.0-rc2 #153 Hardware name: LENOVO 2776LEG/2776LEG, BIOS 6EET55WW (3.15 ) 12/19/2011 0000000000000009 ffff8802327ebb78 ffffffff81380b0e 0000000000000006 ffff8802327ebbc8 ffff8802327ebbb8 ffffffff81038635 0000000000000000 ffffffff811823c7 ffff88021a19e688 ffff88021a19e688 ffff8802302f9310 Call Trace: [] dump_stack+0x55/0x76 [] warn_slowpath_common+0x7c/0x96 [] ? sysfs_open_file+0x77/0x212 [] warn_slowpath_fmt+0x41/0x43 [] ? sysfs_get_active+0x6b/0x82 [] ? sysfs_open_file+0x32/0x212 [] sysfs_open_file+0x77/0x212 [] ? sysfs_schedule_callback+0x1ac/0x1ac [] do_dentry_open+0x17c/0x257 [] finish_open+0x41/0x4f [] do_last+0x80c/0x9ba [] ? inode_permission+0x40/0x42 [] path_openat+0x233/0x4a1 [] do_filp_open+0x35/0x85 [] ? __alloc_fd+0x172/0x184 [] do_sys_open+0x6b/0xfa [] SyS_openat+0xf/0x11 [] system_call_fastpath+0x16/0x1b The failure to restore cpufreq devices on cancelled hibernation is not a new bug. It is caused by the ACPI _PPC call failing unless the hibernate is completed. This makes the acpi_cpufreq driver fail its init. Previously, the cpufreq device could be restored by offlining the cpu temporarily. And as a complete hibernation cycle would do this, it would be automatically restored most of the time. But after commit 5302c3fb2e62 the leftover sysfs attributes will block any device add action. Therefore offlining and onlining CPU 1 will no longer restore the cpufreq object, and a complete suspend/resume cycle will replace it with garbage. Fixes: 5302c3fb2e62 ("cpufreq: Perform light-weight init/teardown during suspend/resume") Cc: 3.12+ # 3.12+ Signed-off-by: Bjørn Mork Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/cpufreq.c | 3 --- 1 file changed, 3 deletions(-) diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index 606224a8abc2..81e9d4412db8 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -2119,9 +2119,6 @@ static int cpufreq_cpu_callback(struct notifier_block *nfb, dev = get_cpu_device(cpu); if (dev) { - if (action & CPU_TASKS_FROZEN) - frozen = true; - switch (action & ~CPU_TASKS_FROZEN) { case CPU_ONLINE: __cpufreq_add_dev(dev, NULL, frozen); From 813e8e3d6aaa0b511126cce15c16a931afffe768 Mon Sep 17 00:00:00 2001 From: Konrad Rzeszutek Wilk Date: Tue, 3 Dec 2013 10:59:58 -0500 Subject: [PATCH 4/4] cpuidle: Check for dev before deregistering it. If not, we could end up in the unfortunate situation where we dereference a NULL pointer b/c we have cpuidle disabled. This is the case when booting under Xen (which uses the ACPI P/C states but disables the CPU idle driver) - and can be easily reproduced when booting with cpuidle.off=1. BUG: unable to handle kernel NULL pointer dereference at (null) IP: [] cpuidle_unregister_device+0x2a/0x90 .. snip.. Call Trace: [] acpi_processor_power_exit+0x3c/0x5c [] acpi_processor_stop+0x61/0xb6 [] __device_release_driver+0fffff81421653>] device_release_driver+0x23/0x30 [] bus_remove_device+0x108/0x180 [] device_del+0x129/0x1c0 [] ? unregister_xenbus_watch+0x1f0/0x1f0 [] device_unregister+0x1e/0x60 [] unregister_cpu+0x39/0x60 [] arch_unregister_cpu+0x23/0x30 [] handle_vcpu_hotplug_event+0xc1/0xe0 [] xenwatch_thread+0x45/0x120 [] ? abort_exclusive_wait+0xb0/0xb0 [] kthread+0xd2/0xf0 [] ? kthread_create_on_node+0x180/0x180 [] ret_from_fork+0x7c/0xb0 [] ? kthread_create_on_node+0x180/0x180 This problem also appears in 3.12 and could be a candidate for backport. Signed-off-by: Konrad Rzeszutek Wilk Cc: All applicable Signed-off-by: Rafael J. Wysocki --- drivers/cpuidle/cpuidle.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c index 2a991e468f78..a55e68f2cfc8 100644 --- a/drivers/cpuidle/cpuidle.c +++ b/drivers/cpuidle/cpuidle.c @@ -400,7 +400,7 @@ EXPORT_SYMBOL_GPL(cpuidle_register_device); */ void cpuidle_unregister_device(struct cpuidle_device *dev) { - if (dev->registered == 0) + if (!dev || dev->registered == 0) return; cpuidle_pause_and_lock();