Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Skip to content
Commit 8b5f866c authored by Heesub Shin's avatar Heesub Shin Committed by Shiraz Hashim
Browse files

staging: ion: shrink highmem pages on kswapd



ION system heap keeps pages in its pool for better performance. When the
system is under memory pressure, slab shrinker calls the callback
registered and then the pages pooled get freed.

When the shrinker is called, it checks gfp_mask and determines whether
the pages from highmem need to be freed or the pages from lowmem.
Usually, slab shrinker is invoked on kswapd context which gfp_mask is
always GFP_KERNEL, so only lowmem pages are released on kswapd context.
This means that highmem pages in the pool are never reclaimed until
direct reclaim occurs. This can be problematic when the page pool holds
excessive amounts of highmem.

For now, the shrinker callback cannot know exactly which zone should be
targeted for reclamation, as enough information are not passed to. Thus,
it makes sense to shrink both lowmem and highmem zone on kswapd context.

Change-Id: Ibf21e36e6d370967fa9166d6e5d66aec98851478
Reported-by: default avatarWonseo Choi <wonseo.choi@samsung.com>
Signed-off-by: default avatarHeesub Shin <heesub.shin@samsung.com>
Reviewed-by: default avatarMitchel Humpherys <mitchelh@codeaurora.org>
Tested-by: default avatarJohn Stultz <john.stultz@linaro.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Git-commit: 0cd2dc4db3ba23ff8ab38b8ae81b126626f795d5
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git


[shashim@codeaurora.org: resolve trivial merge conflict]
Signed-off-by: default avatarShiraz Hashim <shashim@codeaurora.org>
parent 1ec33670
Loading
Loading
Loading
Loading
0% Loading or .
You are about to add 0 people to the discussion. Proceed with caution.
Please register or to comment