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| author |   Pingfan Liu <kernelfans@gmail.com> | 2018-07-31 16:51:32 +0800 |
|---|---|---|
| committer |   Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2018-08-06 12:35:20 +0200 |
| commit | 55f2503c3b69328735e88031ff8d6ba291bd952b (patch) | |
| tree | c89f476f4866d1e3ee11aa8b8601c68a23e3b025 /mm/page_alloc.c | |
| parent | PM / hibernate: Mark expected switch fall-through (diff) | |
| download | linux-dev-55f2503c3b69328735e88031ff8d6ba291bd952b.tar.xz linux-dev-55f2503c3b69328735e88031ff8d6ba291bd952b.zip | |
PM / reboot: Eliminate race between reboot and suspend
At present, "systemctl suspend" and "shutdown" can run in parrallel. A
system can suspend after devices_shutdown(), and resume. Then the shutdown
task goes on to power off. This causes many devices are not really shut
off. Hence replacing reboot_mutex with system_transition_mutex (renamed
from pm_mutex) to achieve the exclusion. The renaming of pm_mutex as
system_transition_mutex can be better to reflect the purpose of the mutex.
Signed-off-by: Pingfan Liu <kernelfans@gmail.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'mm/page_alloc.c')
| -rw-r--r-- | mm/page_alloc.c | 11 |
1 files changed, 6 insertions, 5 deletions
diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 1521100f1e63..e47f9e467408 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -155,16 +155,17 @@ static inline void set_pcppage_migratetype(struct page *page, int migratetype) * The following functions are used by the suspend/hibernate code to temporarily * change gfp_allowed_mask in order to avoid using I/O during memory allocations * while devices are suspended. To avoid races with the suspend/hibernate code, - * they should always be called with pm_mutex held (gfp_allowed_mask also should - * only be modified with pm_mutex held, unless the suspend/hibernate code is - * guaranteed not to run in parallel with that modification). + * they should always be called with system_transition_mutex held + * (gfp_allowed_mask also should only be modified with system_transition_mutex + * held, unless the suspend/hibernate code is guaranteed not to run in parallel + * with that modification). */ static gfp_t saved_gfp_mask; void pm_restore_gfp_mask(void) { - WARN_ON(!mutex_is_locked(&pm_mutex)); + WARN_ON(!mutex_is_locked(&system_transition_mutex)); if (saved_gfp_mask) { gfp_allowed_mask = saved_gfp_mask; saved_gfp_mask = 0; @@ -173,7 +174,7 @@ void pm_restore_gfp_mask(void) void pm_restrict_gfp_mask(void) { - WARN_ON(!mutex_is_locked(&pm_mutex)); + WARN_ON(!mutex_is_locked(&system_transition_mutex)); WARN_ON(saved_gfp_mask); saved_gfp_mask = gfp_allowed_mask; gfp_allowed_mask &= ~(__GFP_IO | __GFP_FS); |