From: Chris Wilson <ch...@chris-wilson.co.uk> Some modules, like i915.ko, use swappable objects and may try to swap them out under memory pressure (via the shrinker). Before doing so, they want to check using get_nr_swap_pages() to see if any swap space is available as otherwise they will waste time purging the object from the device without recovering any memory for the system. This requires the nr_swap_pages counter to be exported to the modules.
Signed-off-by: Chris Wilson <ch...@chris-wilson.co.uk> Cc: "Goel, Akash" <akash.g...@intel.com> Cc: Johannes Weiner <han...@cmpxchg.org> Cc: linux...@kvack.org Link: http://patchwork.freedesktop.org/patch/msgid/1449244734-25733-1-git-send-email-ch...@chris-wilson.co.uk Acked-by: Andrew Morton <a...@linux-foundation.org> Acked-by: Johannes Weiner <han...@cmpxchg.org> Signed-off-by: Daniel Vetter <daniel.vet...@ffwll.ch> (pulled from 4.6-rc1) Signed-off-by: Eric Ernst <eric.er...@linux.intel.com> --- mm/swapfile.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/mm/swapfile.c b/mm/swapfile.c index 58877312cf6b..2d259fdb2347 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -48,6 +48,12 @@ static sector_t map_swap_entry(swp_entry_t, struct block_device**); DEFINE_SPINLOCK(swap_lock); static unsigned int nr_swapfiles; atomic_long_t nr_swap_pages; +/* + * Some modules use swappable objects and may try to swap them out under + * memory pressure (via the shrinker). Before doing so, they may wish to + * check to see if any swap space is available. + */ +EXPORT_SYMBOL_GPL(nr_swap_pages); /* protected with swap_lock. reading in vm_swap_full() doesn't need lock */ long total_swap_pages; static int least_priority; -- 1.9.1 -- _______________________________________________ linux-yocto mailing list linux-yocto@yoctoproject.org https://lists.yoctoproject.org/listinfo/linux-yocto
