Commit Graph

6 Commits

Author SHA1 Message Date
Sherry Yang
8ef4665aa1 android: binder: Add page usage in binder stats
Add the number of active, lru, and free pages for
each binder process in binder stats

Signed-off-by: Sherry Yang <sherryy@android.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-01 08:53:32 +02:00
Sherry Yang
f2517eb76f android: binder: Add global lru shrinker to binder
Hold on to the pages allocated and mapped for transaction
buffers until the system is under memory pressure. When
that happens, use linux shrinker to free pages. Without
using shrinker, patch "android: binder: Move buffer out
of area shared with user space" will cause a significant
slow down for small transactions that fit into the first
page because free list buffer header used to be inlined
with buffer data.

In addition to prevent the performance regression for
small transactions, this patch improves the performance
for transactions that take up more than one page.

Modify alloc selftest to work with the shrinker change.

Test: Run memory intensive applications (Chrome and Camera)
to trigger shrinker callbacks. Binder frees memory as expected.
Test: Run binderThroughputTest with high memory pressure
option enabled.

Signed-off-by: Sherry Yang <sherryy@android.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-28 16:47:17 +02:00
Sherry Yang
74310e06be android: binder: Move buffer out of area shared with user space
Binder driver allocates buffer meta data in a region that is mapped
in user space. These meta data contain pointers in the kernel.

This patch allocates buffer meta data on the kernel heap that is
not mapped in user space, and uses a pointer to refer to the data mapped.

Signed-off-by: Sherry Yang <sherryy@android.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-28 16:47:17 +02:00
Sherry Yang
4175e2b46f android: binder: Add allocator selftest
binder_alloc_selftest tests that alloc_new_buf handles page allocation and
deallocation properly when allocate and free buffers. The test allocates 5
buffers of various sizes to cover all possible page alignment cases, and
frees the buffers using a list of exhaustive freeing order.

Test: boot the device with ANDROID_BINDER_IPC_SELFTEST config option
enabled. Allocator selftest passes.

Signed-off-by: Sherry Yang <sherryy@android.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-28 16:47:17 +02:00
Todd Kjos
53d311cfa1 binder: protect against two threads freeing buffer
Adds protection against malicious user code freeing
the same buffer at the same time which could cause
a crash. Cannot happen under normal use.

Signed-off-by: Todd Kjos <tkjos@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-17 14:47:29 +02:00
Todd Kjos
0c972a05cd binder: move binder_alloc to separate file
Move the binder allocator functionality to its own file

Continuation of splitting the binder allocator from the binder
driver. Split binder_alloc functions from normal binder functions.

Add kernel doc comments to functions declared extern in
binder_alloc.h

Signed-off-by: Todd Kjos <tkjos@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-17 14:47:29 +02:00