From e823407f7b11fa06ba8e7a2801eb9ed11268a7ec Mon Sep 17 00:00:00 2001 From: Ming Lei Date: Fri, 22 Feb 2013 16:34:11 -0800 Subject: pm / runtime: introduce pm_runtime_set_memalloc_noio() Introduce the flag memalloc_noio in 'struct dev_pm_info' to help PM core to teach mm not allocating memory with GFP_KERNEL flag for avoiding probable deadlock. As explained in the comment, any GFP_KERNEL allocation inside runtime_resume() or runtime_suspend() on any one of device in the path from one block or network device to the root device in the device tree may cause deadlock, the introduced pm_runtime_set_memalloc_noio() sets or clears the flag on device in the path recursively. Signed-off-by: Ming Lei Cc: Minchan Kim Cc: Alan Stern Cc: Oliver Neukum Cc: Jiri Kosina Cc: Mel Gorman Cc: KAMEZAWA Hiroyuki Cc: Michal Hocko Cc: Ingo Molnar Cc: Peter Zijlstra Cc: "Rafael J. Wysocki" Cc: Greg KH Cc: Jens Axboe Cc: "David S. Miller" Cc: Eric Dumazet Cc: David Decotigny Cc: Tom Herbert Cc: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/pm.h | 1 + include/linux/pm_runtime.h | 3 +++ 2 files changed, 4 insertions(+) (limited to 'include') diff --git a/include/linux/pm.h b/include/linux/pm.h index 97bcf23e045..e5d7230332a 100644 --- a/include/linux/pm.h +++ b/include/linux/pm.h @@ -537,6 +537,7 @@ struct dev_pm_info { unsigned int irq_safe:1; unsigned int use_autosuspend:1; unsigned int timer_autosuspends:1; + unsigned int memalloc_noio:1; enum rpm_request request; enum rpm_status runtime_status; int runtime_error; diff --git a/include/linux/pm_runtime.h b/include/linux/pm_runtime.h index c785c215abf..7d7e09efff9 100644 --- a/include/linux/pm_runtime.h +++ b/include/linux/pm_runtime.h @@ -47,6 +47,7 @@ extern void pm_runtime_set_autosuspend_delay(struct device *dev, int delay); extern unsigned long pm_runtime_autosuspend_expiration(struct device *dev); extern void pm_runtime_update_max_time_suspended(struct device *dev, s64 delta_ns); +extern void pm_runtime_set_memalloc_noio(struct device *dev, bool enable); static inline bool pm_children_suspended(struct device *dev) { @@ -156,6 +157,8 @@ static inline void pm_runtime_set_autosuspend_delay(struct device *dev, int delay) {} static inline unsigned long pm_runtime_autosuspend_expiration( struct device *dev) { return 0; } +static inline void pm_runtime_set_memalloc_noio(struct device *dev, + bool enable){} #endif /* !CONFIG_PM_RUNTIME */ -- cgit v1.2.3