linux-stable.git/drivers/staging/android/ion, branch v3.16.2

staging: ion: shrink highmem pages on kswapd

2014-05-29T20:40:46+00:00

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.

Reported-by: Wonseo Choi 
Signed-off-by: Heesub Shin 
Reviewed-by: Mitchel Humpherys 
Tested-by: John Stultz 
Signed-off-by: Greg Kroah-Hartman

staging: ion: use compound pages on high order pages for system heap

2014-05-29T20:40:33+00:00

Using compound pages relieves burden on tracking the meta information
which are currently stored in page_info.

Signed-off-by: Heesub Shin 
Reviewed-by: Mitchel Humpherys 
Tested-by: John Stultz 
Signed-off-by: Greg Kroah-Hartman

staging: ion: remove struct ion_page_pool_item

2014-05-29T20:40:33+00:00

The page pool uses an internal data structure, ion_page_pool_item, for
wrapping pooled pages and constructing a list. As the struct page
already provides ways for doing exactly the same thing, we do not need
to reinvent the wheel. This commit removes the data structure and slab
allocations for it.

Signed-off-by: Heesub Shin 
Reviewed-by: Mitchel Humpherys 
Tested-by: John Stultz 
Signed-off-by: Greg Kroah-Hartman

staging: ion: simplify ion_page_pool_total()

2014-05-29T20:40:33+00:00

ion_page_pool_total() returns the total number of pages in the pool.
Depending on the argument passed, it counts highmem pages in or not.
This commit simplifies the code lines for better readability.

Signed-off-by: Heesub Shin 
Reviewed-by: Mitchel Humpherys 
Tested-by: John Stultz 
Signed-off-by: Greg Kroah-Hartman

staging: ion: tidy up a bit

2014-05-29T20:40:33+00:00

For aesthetics and readability, rename goto labels, remove
useless code lines, and clarify function return type.

Signed-off-by: Heesub Shin 
Reviewed-by: Mitchel Humpherys 
Tested-by: John Stultz 
Signed-off-by: Greg Kroah-Hartman

staging: ion: WARN when the handle kmap_cnt is going to wrap around

2014-05-23T22:23:15+00:00

There are certain client bugs (double unmap, for example) that can cause
the handle->kmap_cnt (an unsigned int) to wrap around from zero. This
causes problems when the handle is destroyed because we have:

        while (handle->kmap_cnt)
                ion_handle_kmap_put(handle);

which takes a long time to complete when kmap_cnt starts at ~0 and can
result in a watchdog timeout.

WARN and bail when kmap_cnt is about to wrap around from zero.

Signed-off-by: Mitchel Humpherys 
Acked-by: Colin Cross 
Signed-off-by: Greg Kroah-Hartman

staging: android: fix missing a blank line after declarations

2014-05-03T23:46:30+00:00

This patch fixes "Missing a blank line after declarations" warnings.

Signed-off-by: Seunghun Lee 
Signed-off-by: Greg Kroah-Hartman

Staging: android: ion: duplicated clearing of sg_table

2014-04-25T22:17:31+00:00

Because sg_table is cleared in sg_alloc_table via memset we don't need to use
kzalloc to allocate sg_table.

Signed-off-by: Gioh Kim 
Signed-off-by: Greg Kroah-Hartman

staging: android: ion: Use ERR_CAST instead of ERR_PTR

2014-03-13T23:34:02+00:00

Fix the following coccinelle warnings in ion.c:
drivers/staging/android/ion/ion.c:511:9-16: WARNING: ERR_CAST can be used with buffer
drivers/staging/android/ion/ion.c:218:9-16: WARNING: ERR_CAST can be used with table
drivers/staging/android/ion/ion.c:1150:9-16: WARNING: ERR_CAST can be used with dmabuf

Signed-off-by: Iulia Manda 
Acked-by: Paul E. McKenney 
Signed-off-by: Peter P Waskiewicz Jr

staging: android: ion: Replace seq_printf with seq_puts

2014-03-13T23:33:54+00:00

It is preferred to use seq_puts instead of seq_printf here, as it suffices string printing.

Signed-off-by: Iulia Manda 
Acked-by: Paul E. McKenney 
Signed-off-by: Peter P Waskiewicz Jr