perf_lock_task_context() is buggy because it can return a dead
context.
the RCU read lock in perf_lock_task_context() only guarantees
the memory won't get freed, it doesn't guarantee the object is
valid (in our case refcount > 0).
Therefore we can return a locked object that can get freed the
moment we release the rcu read lock.
perf_pin_task_context() then increases the refcount and does an
unlock on freed memory.
That increased refcount will cause a double free, in case it
started out with 0.
Ammend this by including the get_ctx() functionality in
perf_lock_task_context() (all users already did this later
anyway), and return a NULL context when the found one is
already dead.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
For video4linux we sometimes need to probe for a single i2c address.
Normally you would do it like this:
static const unsigned short addrs[] = {
addr, I2C_CLIENT_END
};
client = i2c_new_probed_device(adapter, &info, addrs);
This is a bit awkward and I came up with this macro:
#define V4L2_I2C_ADDRS(addr, addrs...) \
((const unsigned short []){ addr, ## addrs, I2C_CLIENT_END })
This can construct a list of one or more i2c addresses on the fly. But
this is something that really belongs in i2c.h, renamed to I2C_ADDRS.
With this macro we can just do:
client = i2c_new_probed_device(adapter, &info, I2C_ADDRS(addr));
Note that this can also be used to initialize an array:
static const unsigned short addrs[] = I2C_ADDRS(0x2a, 0x2c);
Whether you want to is another matter, but it works. This functionality is
also available in the oldest supported gcc (3.2).
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Surround i2c function declarations with ifdefs, so that they aren't
advertised when i2c-core isn't actually built. That way, drivers using
these functions unconditionally will result in an immediate build
failure, rather than a late linking failure which is harder to figure
out.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Paul Mundt <lethal@linux-sh.org>
By using rwsem we can easily manage recursive calls of
i2c_scan_static_board_info() function without breaking the locking.
Signed-off-by: Rodolfo Giometti <giometti@linux.it>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Add a sysfs interface to instantiate and delete I2C devices. This is
primarily a replacement of the force_* module parameters implemented
by some i2c drivers. These module parameters were implemented
internally by the I2C_CLIENT_INSMOD* macros, which don't scale well.
This can also be used when developing a driver on a self-soldered
board which doesn't yet have proper I2C device declaration at the
platform level, and presumably for various debugging situations.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: David Brownell <dbrownell@users.sourceforge.net>
The i2c-core code tends to hold the core lock for longer than it
should. Limit locking to the necessary sections for both performance
and clarity. This is also a requirement to support I2C multiplexers in
the future.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Tested-by: Rodolfo Giometti <giometti@linux.it>
Cc: David Brownell <dbrownell@users.sourceforge.net>
We used to maintain our own per-adapter list of i2c clients, but this
is redundant with what the driver core does, and no longer needed.
Just drop the redundant list.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Legacy i2c drivers are gone, all drivers are new-style now, so there
is no point to check.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Now that i2c_attach_client is no longer exported, it doesn't need to
be a separate function. Merge it into its only user, i2c_new_device.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: David Brownell <dbrownell@users.sourceforge.net>
The legacy i2c_probe() function has no users left, get rid of it.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: David Brownell <dbrownell@users.sourceforge.net>
We converted all the legacy i2c drivers so we can finally get rid of
the legacy binding model. Hooray!
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: David Brownell <dbrownell@users.sourceforge.net>
These methods were useful in the legacy binding model but no longer in
the new (standard) binding model. There are no users left so we can
drop them.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Improve a few details in perfcounter call-chain recording that
makes use of fast-GUP:
- Use ACCESS_ONCE() to observe the pte value. ptes are fundamentally
racy and can be changed on another CPU, so we have to be careful
about how we access them. The PAE branch is already careful with
read-barriers - but the non-PAE and 64-bit side needs an
ACCESS_ONCE() to make sure the pte value is observed only once.
- make the checks a bit stricter so that we can feed it any kind of
cra^H^H^H user-space input ;-)
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The task migrations counter was causing rare and hard to decypher
memory corruptions under load. After a day of debugging and bisection
we found that the problem was introduced with:
3f731ca: perf_counter: Fix cpu migration counter
Turning them off fixes the crashes. Incidentally, the whole
perf_counter_task_migration() logic can be done simpler as well,
by injecting a proper sw-counter event.
This cleanup also fixed the crashes. The precise failure mode is
not completely clear yet, but we are clearly not unhappy about
having a fix ;-)
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Add a data file header so we can transfer data between record and report.
LKML-Reference: <new-submission>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Update the tools to reflect the new callchain sampling format.
LKML-Reference: <new-submission>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Before exposing upstream tools to a callchain-samples ABI, tidy it
up to make it more extensible in the future:
Use markers in the IP chain to denote context, use (u64)-1..-4095 range
for these context markers because we use them for ERR_PTR(), so these
addresses are unlikely to be mapped.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Warning(block/blk-settings.c:108): No description found for parameter 'lim'
Warning(block/blk-settings.c:108): Excess function parameter 'limits' description in 'blk_set_default_limits'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Commit b696fdc259 ("sparc64: Defer
cpu_data() setup until end of per-cpu data initialization.") broke
bootup for UP builds because the cpu_data() initialization only
occurs in setup_per_cpu_areas() which is never compiled in nor
called in UP builds.
Fix this up by calling the setups directly from init_64.c when
non-SMP.
Reported-by: Alexander Beregalov <a.beregalov@gmail.com>
Tested-by: Alexander Beregalov <a.beregalov@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Follow-up to "block: enable by default support for large devices
and files on 32-bit archs".
Rename CONFIG_LBD to CONFIG_LBDAF to:
- allow update of existing [def]configs for "default y" change
- reflect that it is used also for large files support nowadays
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
The irq_panic function is only used when CONFIG_DEBUG_ICACHE_CHECK is
enabled, so move the conditional build to the Makefile rather than
wrapping all of the contents of the file.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Make sure we pull in asm/io.h when exporting symbols for the I/O functions
so we don't end up with a build failure due to missing prototypes.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Convert to test_bit() as that is what pretty much everyone uses and allows
us to migrate asm/bitops.h to the asm-generic version.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
In theory now that the AGP subsystem is using struct page, we should
have on problems enabling GEM on PAE systems.
Signed-off-by: Dave Airlie <airlied@redhat.com>
This switches AGP to use an array of pages for tracking the
pages allocated to the GART. This should enable GEM on PAE to work
a lot better as we can pass highmem pages to the PAT code and it will
do the right thing with them.
Signed-off-by: Dave Airlie <airlied@redhat.com>
Add M1621 chipset name to ali-agp, preventing "Detected ALi M???? chipset"
message.
Signed-off-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>
For security purpose we want to make sure the userspace process doesn't
access memory beyond buffer it owns. To achieve this we need to check
states the userspace program. For color buffer and zbuffer we check that
the clipping register will discard access beyond buffers set as color
or zbuffer. For vertex buffer we check that no vertex fetch will happen
beyond buffer end. For texture we check various texture states (number
of mipmap level, texture size, texture depth, ...) to compute the amount
of memory the texture fetcher might access.
The command stream checking impact the performances so far quick benchmark
shows an average of 3% decrease in fps of various applications. It can
be optimized a bit more by caching result of checking and thus avoid a
full recheck if no states changed since last check.
Note that this patch is still incomplete on checking side as it doesn't
check 2d rendering states.
Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
also for the atomic path by using a common code-path.
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
