• Ming Lei's avatar
    pm / runtime: introduce pm_runtime_set_memalloc_noio() · e823407f
    Ming Lei authored
    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: default avatarMing Lei <ming.lei@canonical.com>
    Cc: Minchan Kim <minchan@kernel.org>
    Cc: Alan Stern <stern@rowland.harvard.edu>
    Cc: Oliver Neukum <oneukum@suse.de>
    Cc: Jiri Kosina <jiri.kosina@suse.com>
    Cc: Mel Gorman <mel@csn.ul.ie>
    Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
    Cc: Michal Hocko <mhocko@suse.cz>
    Cc: Ingo Molnar <mingo@redhat.com>
    Cc: Peter Zijlstra <peterz@infradead.org>
    Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
    Cc: Greg KH <greg@kroah.com>
    Cc: Jens Axboe <axboe@kernel.dk>
    Cc: "David S. Miller" <davem@davemloft.net>
    Cc: Eric Dumazet <eric.dumazet@gmail.com>
    Cc: David Decotigny <david.decotigny@google.com>
    Cc: Tom Herbert <therbert@google.com>
    Cc: Ingo Molnar <mingo@elte.hu>
    Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    e823407f
runtime.c 38.1 KB