task->signal == NULL is not possible, so no need for these checks.
Suggested-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
LMK should not directly check for task->mm. The reason is that the
process' threads may exit or detach its mm via use_mm(), but other
threads may still have a valid mm. To catch this we use
find_lock_task_mm(), which walks up all threads and returns an
appropriate task (with lock held).
Suggested-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Grabbing tasklist_lock has its disadvantages, i.e. it blocks
process creation and destruction. If there are lots of processes,
blocking doesn't sound as a great idea.
For LMK, it is sufficient to surround tasks list traverse with
rcu_read_{,un}lock().
>From now on using force_sig() is not safe, as it can race with an
already exiting task, so we use send_sig() now. As a downside, it
won't kill PID namespace init processes, but that's not what we
want anyway.
Suggested-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add comment to explain when w_off is not updated in case of failed second
fragment copy to buffer.
Signed-off-by: Tim Bird <tim.bird@am.sony.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add commentary, rename the function and make the code easier to read.
Signed-off-by: Tim Bird <tim.bird@am.sony.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If mutex_lock waits, it will return in state TASK_RUNNING,
rubbing out the effect of prepare_to_wait().
Signed-off-by: Tim Bird <tim.bird@am.sony.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Make this code slightly easier to read, and eliminate calls
to sub-routines. Some of these were previously optimized away
by the compiler, but one memcpy was not.
In my testing, this makes the code about 20% smaller, and
has no sub-routine calls and no branches (on ARM).
v2 of this patch is, IMHO, easier to read than v1. Compared to
that patch it uses __u8 instead of unsigned char, for
consistency with the __u16 val data type, simplifies the
conditional expression, adds a another comment, and
moves a common statement out of the if.
Signed-off-by: Tim Bird <tim.bird@am.sony.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Convert to function and add log as a parameter, rather than relying
on log in the context of the macro.
Signed-off-by: Tim Bird <tim.bird@am.sony.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Just made it more neat and not bother scripts/checkpatch.pl
Signed-off-by: Tracey Dent <tdent48227@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Minor cleanups that consist of removal of a whitespace and
make file_operations const.
Signed-off-by: Tracey Dent <tdent48227@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The semantic patch that makes this change is available
in scripts/coccinelle/api/resource_size.cocci.
More information about semantic patching is available at
http://coccinelle.lip6.fr/
Signed-off-by: Thomas Meyer <thomas@m3y3r.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Below is a patch that fixes some typos in some comments.
Signed-off-by: Justin P. Mattock <justinmattock@gmail.com>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch fixes some 80 chatacters limit warnings in the lowmemorykiller.c file
Signed-off-by: Marco Navarra <fromenglish@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch fixes a simple tab-space warning in binder.h found by checkpatch tool
Signed-off-by: Marco Navarra <fromenglish@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Fixes checkpatch warnings with the ashmem.c file
CC: Brian Swetland <swetland@google.com>
CC: Colin Cross <ccross@android.com>
CC: Arve Hjønnevåg <arve@android.com>
CC: Dima Zavin <dima@android.com>
CC: Robert Love <rlove@google.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The arguments to shrink functions have changed, update
ashmem_shrink to match.
Signed-off-by: Colin Cross <ccross@android.com>
[jstultz: tweaked commit subject]
CC: Brian Swetland <swetland@google.com>
CC: Colin Cross <ccross@android.com>
CC: Arve Hjønnevåg <arve@android.com>
CC: Dima Zavin <dima@android.com>
CC: Robert Love <rlove@google.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The anonymous shared memory (ashmem) subsystem provides a
Unix-y,file-based shared memory interface to user-space. It
works like anonymous memory (e.g. mmapping fd=0) except if
you share the file descriptor via the usual means, you will
share the mapping. The shared memory can be accessed via both
mmap or file I/O. The backing store is a simple shmem file.
Additionally, ashmem introduces the concept of page pinning.
Pinned pages (the default) behave like any anonymous memory.
Unpinned pages are available to the kernel for eviction during
VM pressure. When repinning the pages, the return value
instructs user-space as to any eviction. In this manner,
user-space processes may implement caching and similar
resource management that efficiently integrates with kernel
memory management.
Signed-off-by: Robert Love <rlove@google.com>
ashmem: Don't install fault handler for private mmaps.
Ashmem is used to create named private heaps. If this heap is backed
by a tmpfs file it will allocate two pages for every page touched.
In 2.6.27, the extra page would later be freed, but 2.6.29 does not
scan anonymous pages when running without swap so the memory is not
freed while the file is referenced. This change changes the behavior
of private ashmem mmaps to match /dev/zero instead tmpfs.
Signed-off-by: Arve Hjønnevåg <arve@android.com>
ashmem: Add common prefix to name reported in /proc/pid/maps
Signed-off-by: Arve Hjønnevåg <arve@android.com>
ashmem: don't require a page aligned size
This makes ashmem more similar to shmem and mmap, by
not requiring the specified size to be page aligned,
instead rounding it internally as needed.
Signed-off-by: Marco Nelissen <marcone@android.com>
[jstultz: Improved commit subject and included patch description
from rlove. Also moved ashmem files to staging dir, and reworked
code to avoid touching mm/shmem.c while we're in staging.]
CC: Brian Swetland <swetland@google.com>
CC: Colin Cross <ccross@android.com>
CC: Arve Hjønnevåg <arve@android.com>
CC: Dima Zavin <dima@android.com>
CC: Robert Love <rlove@google.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This adds the Android pmem driver to the staging tree.
[At this point in time, it is dependent on the ARM platform, due to some
build issues that require it. - gregkh]
Signed-off-by: Rebecca Schultz <rschultz@google.com>
Signed-off-by: Rebecca Schultz Zavin <rebecca@android.com>
Signed-off-by: Dima Zavin <dima@android.com>
Signed-off-by: Jamie Gennis <jgennis@google.com>
Cc: Brian Swetland <swetland@google.com>
Cc: Arve Hjønnevåg <arve@android.com>
Cc: Colin Cross <ccross@android.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This adds the Android switch driver code to the staging tree.
[Note, this code was located in drivers/switch/ in the Android kernel
releases, but as that api wasn't generally accepted, and the interface
is working toward changing to the newly proposed extcon inteface, this
driver was placed here until the extcon code is merged into mainline and
the Android userspace code is converted over to using it. - gregkh]
Signed-off-by: Arve Hjønnevåg <arve@android.com>
Signed-off-by: Mike Lockwood <lockwood@android.com>
Cc: MyungJoo Ham <myungjoo.ham@samsung.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Donggeun Kim <dg77.kim@samsung.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: MyungJoo Ham <myungjoo.ham@gmail.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: NeilBrown <neilb@suse.de>
Cc: Morten CHRISTIANSEN <morten.christiansen@stericsson.com>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: John Stultz <john.stultz@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch fixes some space-before-tabs warnings found by checkpatch tool on the staging android driver file logger.c
Signed-off-by: Marco Navarra <fromenglish@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Allow the board file to pass a boot info string through the
platform data that is appended to the /proc/last_kmsg file.
[moved the .h file to drivers/staging/android/ to be self-contained - gregkh]
Signed-off-by: Colin Cross <ccross@android.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The arguments to shrink functions have changed, update
lowmem_shrink to match.
Signed-off-by: Colin Cross <ccross@android.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Now that we're murder-synchronous, this code path will never be
called (and if it does, it doesn't tell us anything useful other
than we killed a task that was already being killed by somebody
else but hadn't gotten its' signal yet)
Signed-off-by: San Mehat <san@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
binder_deferred_release was not unmapping the page from the buffer
before freeing it, causing memory corruption. This only happened
when page(s) had not been freed by binder_update_page_range, which
properly unmaps the pages.
This only happens on architectures with VIPT aliasing.
To reproduce, create a program which opens, mmaps, munmaps, then closes
the binder very quickly. This should leave a page allocated when the
binder is released. When binder_deferrred_release is called on the
close, the page will remain mapped to the address in the linear
proc->buffer. Later, we may map the same physical page to a different
virtual address that has different coloring, and this may cause
aliasing to occur.
PAGE_POISONING will greatly increase your chances of noticing any
problems.
Signed-off-by: Christopher Lais <chris+android@zenthought.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch optimizes lowmemkiller to not do any work when it has an outstanding
kill-request. This greatly reduces the pressure on the task_list lock
(improving interactivity), as well as improving the vmscan performance
when under heavy memory pressure (by up to 20x in tests).
Note: For this enhancement to work, you need CONFIG_PROFILING
Signed-off-by: San Mehat <san@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Under certain circumstances, a process can take awhile to
handle a sig-kill (especially if it's in a scheduler group with
a very low share ratio). When this occurs, lowmemkiller returns
to vmscan indicating the process memory has been freed - even
though the process is still waiting to die. Since the memory
hasn't actually freed, lowmemkiller is called again shortly after,
and picks the same process to die; regardless of the fact that
it has already been 'scheduled' to die and the memory has already
been reported to vmscan as having been freed.
Solution is to check fatal_signal_pending() on the selected
task, and if it's already pending destruction return; indicating
to vmscan that no resources were freed on this pass.
Signed-off-by: San Mehat <san@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Some drivers flush the global workqueue when closed. This would deadlock if
the last reference to the file was released from the binder.
Signed-off-by: Arve Hjønnevåg <arve@android.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The timed output device never previously checked the return value of sscanf,
resulting in an uninitialized int being passed to enable() if input value
was invalid.
Signed-off-by: Mike Lockwood <lockwood@android.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
[Note, this is part of a patch from Sam, just the drivers/staging/
portion, that adds a function that the apanic code calls, but the apanic
code isn't here, so just include part of this to make merges and diffs
easier and this keeps things self-contained - gregkh]
Signed-off-by: San Mehat <san@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This reverts commit 2cdf99ce2b.
It now builds, so this can be reverted.
Cc: Arve Hjønnevåg <arve@android.com>
Cc: Brian Swetland <swetland@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This reverts commit b0a0ccfad8.
Turns out I was wrong, we want these in the tree.
Note, I've disabled the drivers from the build at the moment, so other
patches can be applied to fix some build issues due to internal api
changes since the code was removed from the tree.
Cc: Arve Hjønnevåg <arve@android.com>
Cc: Brian Swetland <swetland@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
These drivers are no longer being developed and the original authors
seem to have abandonded them and hence, do not want them in the mainline
kernel tree.
So sad :(
Cc: Brian Swetland <swetland@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
