From c9d967b2ce40d71e968eb839f36c936b8a9cf1ea Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Thu, 13 Jan 2022 19:44:20 +0100 Subject: PM: wakeup: simplify the output logic of pm_show_wakelocks() The buffer handling in pm_show_wakelocks() is tricky, and hopefully correct. Ensure it really is correct by using sysfs_emit_at() which handles all of the tricky string handling logic in a PAGE_SIZE buffer for us automatically as this is a sysfs file being read from. Signed-off-by: Greg Kroah-Hartman Reviewed-by: Lee Jones Signed-off-by: Rafael J. Wysocki --- kernel/power/wakelock.c | 11 ++++------- 1 file changed, 4 insertions(+), 7 deletions(-) (limited to 'kernel/power') diff --git a/kernel/power/wakelock.c b/kernel/power/wakelock.c index 105df4dfc783..52571dcad768 100644 --- a/kernel/power/wakelock.c +++ b/kernel/power/wakelock.c @@ -39,23 +39,20 @@ ssize_t pm_show_wakelocks(char *buf, bool show_active) { struct rb_node *node; struct wakelock *wl; - char *str = buf; - char *end = buf + PAGE_SIZE; + int len = 0; mutex_lock(&wakelocks_lock); for (node = rb_first(&wakelocks_tree); node; node = rb_next(node)) { wl = rb_entry(node, struct wakelock, node); if (wl->ws->active == show_active) - str += scnprintf(str, end - str, "%s ", wl->name); + len += sysfs_emit_at(buf, len, "%s ", wl->name); } - if (str > buf) - str--; - str += scnprintf(str, end - str, "\n"); + len += sysfs_emit_at(buf, len, "\n"); mutex_unlock(&wakelocks_lock); - return (str - buf); + return len; } #if CONFIG_PM_WAKELOCKS_LIMIT > 0 -- cgit v1.3-8-gc7d7 From 33569ef3c754a82010f266b7b938a66a3ccf90a4 Mon Sep 17 00:00:00 2001 From: Amadeusz Sławiński Date: Wed, 19 Jan 2022 11:47:51 +0100 Subject: PM: hibernate: Remove register_nosave_region_late() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit It is an unused wrapper forcing kmalloc allocation for registering nosave regions. Also, rename __register_nosave_region() to register_nosave_region() now that there is no need for disambiguation. Signed-off-by: Amadeusz Sławiński Reviewed-by: Cezary Rojewski Signed-off-by: Rafael J. Wysocki --- include/linux/suspend.h | 11 +---------- kernel/power/snapshot.c | 21 +++++++-------------- 2 files changed, 8 insertions(+), 24 deletions(-) (limited to 'kernel/power') diff --git a/include/linux/suspend.h b/include/linux/suspend.h index 5785d909c321..3e8ecdebe601 100644 --- a/include/linux/suspend.h +++ b/include/linux/suspend.h @@ -430,15 +430,7 @@ struct platform_hibernation_ops { #ifdef CONFIG_HIBERNATION /* kernel/power/snapshot.c */ -extern void __register_nosave_region(unsigned long b, unsigned long e, int km); -static inline void __init register_nosave_region(unsigned long b, unsigned long e) -{ - __register_nosave_region(b, e, 0); -} -static inline void __init register_nosave_region_late(unsigned long b, unsigned long e) -{ - __register_nosave_region(b, e, 1); -} +extern void register_nosave_region(unsigned long b, unsigned long e); extern int swsusp_page_is_forbidden(struct page *); extern void swsusp_set_page_free(struct page *); extern void swsusp_unset_page_free(struct page *); @@ -458,7 +450,6 @@ int pfn_is_nosave(unsigned long pfn); int hibernate_quiet_exec(int (*func)(void *data), void *data); #else /* CONFIG_HIBERNATION */ static inline void register_nosave_region(unsigned long b, unsigned long e) {} -static inline void register_nosave_region_late(unsigned long b, unsigned long e) {} static inline int swsusp_page_is_forbidden(struct page *p) { return 0; } static inline void swsusp_set_page_free(struct page *p) {} static inline void swsusp_unset_page_free(struct page *p) {} diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c index f7a986078213..330d49937692 100644 --- a/kernel/power/snapshot.c +++ b/kernel/power/snapshot.c @@ -978,8 +978,7 @@ static void memory_bm_recycle(struct memory_bitmap *bm) * Register a range of page frames the contents of which should not be saved * during hibernation (to be used in the early initialization code). */ -void __init __register_nosave_region(unsigned long start_pfn, - unsigned long end_pfn, int use_kmalloc) +void __init register_nosave_region(unsigned long start_pfn, unsigned long end_pfn) { struct nosave_region *region; @@ -995,18 +994,12 @@ void __init __register_nosave_region(unsigned long start_pfn, goto Report; } } - if (use_kmalloc) { - /* During init, this shouldn't fail */ - region = kmalloc(sizeof(struct nosave_region), GFP_KERNEL); - BUG_ON(!region); - } else { - /* This allocation cannot fail */ - region = memblock_alloc(sizeof(struct nosave_region), - SMP_CACHE_BYTES); - if (!region) - panic("%s: Failed to allocate %zu bytes\n", __func__, - sizeof(struct nosave_region)); - } + /* This allocation cannot fail */ + region = memblock_alloc(sizeof(struct nosave_region), + SMP_CACHE_BYTES); + if (!region) + panic("%s: Failed to allocate %zu bytes\n", __func__, + sizeof(struct nosave_region)); region->start_pfn = start_pfn; region->end_pfn = end_pfn; list_add_tail(®ion->list, &nosave_regions); -- cgit v1.3-8-gc7d7 From cb1f65c1e1424a4b5e4a86da8aa3b8fd8459c8ec Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Fri, 4 Feb 2022 18:35:22 +0100 Subject: PM: s2idle: ACPI: Fix wakeup interrupts handling After commit e3728b50cd9b ("ACPI: PM: s2idle: Avoid possible race related to the EC GPE") wakeup interrupts occurring immediately after the one discarded by acpi_s2idle_wake() may be missed. Moreover, if the SCI triggers again immediately after the rearming in acpi_s2idle_wake(), that wakeup may be missed too. The problem is that pm_system_irq_wakeup() only calls pm_system_wakeup() when pm_wakeup_irq is 0, but that's not the case any more after the interrupt causing acpi_s2idle_wake() to run until pm_wakeup_irq is cleared by the pm_wakeup_clear() call in s2idle_loop(). However, there may be wakeup interrupts occurring in that time frame and if that happens, they will be missed. To address that issue first move the clearing of pm_wakeup_irq to the point at which it is known that the interrupt causing acpi_s2idle_wake() to tun will be discarded, before rearming the SCI for wakeup. Moreover, because that only reduces the size of the time window in which the issue may manifest itself, allow pm_system_irq_wakeup() to register two second wakeup interrupts in a row and, when discarding the first one, replace it with the second one. [Of course, this assumes that only one wakeup interrupt can be discarded in one go, but currently that is the case and I am not aware of any plans to change that.] Fixes: e3728b50cd9b ("ACPI: PM: s2idle: Avoid possible race related to the EC GPE") Cc: 5.4+ # 5.4+ Signed-off-by: Rafael J. Wysocki --- drivers/acpi/sleep.c | 1 + drivers/base/power/wakeup.c | 41 ++++++++++++++++++++++++++++++++++------- include/linux/suspend.h | 4 ++-- kernel/power/main.c | 5 ++++- kernel/power/process.c | 2 +- kernel/power/suspend.c | 2 -- 6 files changed, 42 insertions(+), 13 deletions(-) (limited to 'kernel/power') diff --git a/drivers/acpi/sleep.c b/drivers/acpi/sleep.c index fac7c9d4c9a1..d4fbea91ab6b 100644 --- a/drivers/acpi/sleep.c +++ b/drivers/acpi/sleep.c @@ -758,6 +758,7 @@ bool acpi_s2idle_wake(void) return true; } + pm_wakeup_clear(acpi_sci_irq); rearm_wake_irq(acpi_sci_irq); } diff --git a/drivers/base/power/wakeup.c b/drivers/base/power/wakeup.c index 99bda0da23a8..8666590201c9 100644 --- a/drivers/base/power/wakeup.c +++ b/drivers/base/power/wakeup.c @@ -34,7 +34,8 @@ suspend_state_t pm_suspend_target_state; bool events_check_enabled __read_mostly; /* First wakeup IRQ seen by the kernel in the last cycle. */ -unsigned int pm_wakeup_irq __read_mostly; +static unsigned int wakeup_irq[2] __read_mostly; +static DEFINE_RAW_SPINLOCK(wakeup_irq_lock); /* If greater than 0 and the system is suspending, terminate the suspend. */ static atomic_t pm_abort_suspend __read_mostly; @@ -942,19 +943,45 @@ void pm_system_cancel_wakeup(void) atomic_dec_if_positive(&pm_abort_suspend); } -void pm_wakeup_clear(bool reset) +void pm_wakeup_clear(unsigned int irq_number) { - pm_wakeup_irq = 0; - if (reset) + raw_spin_lock_irq(&wakeup_irq_lock); + + if (irq_number && wakeup_irq[0] == irq_number) + wakeup_irq[0] = wakeup_irq[1]; + else + wakeup_irq[0] = 0; + + wakeup_irq[1] = 0; + + raw_spin_unlock_irq(&wakeup_irq_lock); + + if (!irq_number) atomic_set(&pm_abort_suspend, 0); } void pm_system_irq_wakeup(unsigned int irq_number) { - if (pm_wakeup_irq == 0) { - pm_wakeup_irq = irq_number; + unsigned long flags; + + raw_spin_lock_irqsave(&wakeup_irq_lock, flags); + + if (wakeup_irq[0] == 0) + wakeup_irq[0] = irq_number; + else if (wakeup_irq[1] == 0) + wakeup_irq[1] = irq_number; + else + irq_number = 0; + + raw_spin_unlock_irqrestore(&wakeup_irq_lock, flags); + + if (irq_number) pm_system_wakeup(); - } +} + +unsigned int pm_wakeup_irq(void) +{ + return wakeup_irq[0]; } /** diff --git a/include/linux/suspend.h b/include/linux/suspend.h index 3e8ecdebe601..300273ff40cc 100644 --- a/include/linux/suspend.h +++ b/include/linux/suspend.h @@ -497,14 +497,14 @@ extern void ksys_sync_helper(void); /* drivers/base/power/wakeup.c */ extern bool events_check_enabled; -extern unsigned int pm_wakeup_irq; extern suspend_state_t pm_suspend_target_state; extern bool pm_wakeup_pending(void); extern void pm_system_wakeup(void); extern void pm_system_cancel_wakeup(void); -extern void pm_wakeup_clear(bool reset); +extern void pm_wakeup_clear(unsigned int irq_number); extern void pm_system_irq_wakeup(unsigned int irq_number); +extern unsigned int pm_wakeup_irq(void); extern bool pm_get_wakeup_count(unsigned int *count, bool block); extern bool pm_save_wakeup_count(unsigned int count); extern void pm_wakep_autosleep_enabled(bool set); diff --git a/kernel/power/main.c b/kernel/power/main.c index 44169f3081fd..7e646079fbeb 100644 --- a/kernel/power/main.c +++ b/kernel/power/main.c @@ -504,7 +504,10 @@ static ssize_t pm_wakeup_irq_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { - return pm_wakeup_irq ? sprintf(buf, "%u\n", pm_wakeup_irq) : -ENODATA; + if (!pm_wakeup_irq()) + return -ENODATA; + + return sprintf(buf, "%u\n", pm_wakeup_irq()); } power_attr_ro(pm_wakeup_irq); diff --git a/kernel/power/process.c b/kernel/power/process.c index b7e7798637b8..11b570fcf049 100644 --- a/kernel/power/process.c +++ b/kernel/power/process.c @@ -134,7 +134,7 @@ int freeze_processes(void) if (!pm_freezing) atomic_inc(&system_freezing_cnt); - pm_wakeup_clear(true); + pm_wakeup_clear(0); pr_info("Freezing user space processes ... "); pm_freezing = true; error = try_to_freeze_tasks(true); diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c index 80cc1f0f502b..6fcdee7e87a5 100644 --- a/kernel/power/suspend.c +++ b/kernel/power/suspend.c @@ -136,8 +136,6 @@ static void s2idle_loop(void) break; } - pm_wakeup_clear(false); - s2idle_enter(); } -- cgit v1.3-8-gc7d7