locking/atomics: COCCINELLE/treewide: Convert trivial ACCESS_ONCE() patterns to READ_ONCE()/WRITE_ONCE()

Please do not apply this to mainline directly, instead please re-run the
coccinelle script shown below and apply its output.

For several reasons, it is desirable to use {READ,WRITE}_ONCE() in
preference to ACCESS_ONCE(), and new code is expected to use one of the
former. So far, there's been no reason to change most existing uses of
ACCESS_ONCE(), as these aren't harmful, and changing them results in
churn.

However, for some features, the read/write distinction is critical to
correct operation. To distinguish these cases, separate read/write
accessors must be used. This patch migrates (most) remaining
ACCESS_ONCE() instances to {READ,WRITE}_ONCE(), using the following
coccinelle script:

----
// Convert trivial ACCESS_ONCE() uses to equivalent READ_ONCE() and
// WRITE_ONCE()

// $ make coccicheck COCCI=/home/mark/once.cocci SPFLAGS="--include-headers" MODE=patch

virtual patch

@ depends on patch @
expression E1, E2;
@@

- ACCESS_ONCE(E1) = E2
+ WRITE_ONCE(E1, E2)

@ depends on patch @
expression E;
@@

- ACCESS_ONCE(E)
+ READ_ONCE(E)
----
Signed-off-by: NMark Rutland <mark.rutland@arm.com>
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: davem@davemloft.net
Cc: linux-arch@vger.kernel.org
Cc: mpe@ellerman.id.au
Cc: shuah@kernel.org
Cc: snitzer@redhat.com
Cc: thor.thayer@linux.intel.com
Cc: tj@kernel.org
Cc: viro@zeniv.linux.org.uk
Cc: will.deacon@arm.com
Link: http://lkml.kernel.org/r/1508792849-3115-19-git-send-email-paulmck@linux.vnet.ibm.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

1,TDR will kickout guilty job if it hang exceed the threshold
of the given one from kernel paramter "job_hang_limit", that
way a bad command stream will not infinitly cause GPU hang.

by default this threshold is 1 so a job will be kicked out
after it hang.

2,if a job timeout TDR routine will not reset all sched/ring,
instead if will only reset on the givn one which is indicated
by @job of amdgpu_sriov_gpu_reset, that way we don't need to
reset and recover each sched/ring if we already know which job
cause GPU hang.

3,unblock sriov_gpu_reset for AI family.

V2:
1:put kickout guilty job after sched parked.
2:since parking scheduler prior to kickout already occupies a
while, we can do last check on the in question job before
doing hw_reset.

TODO:
1:when a job is considered as guilty, we should mark some flag
in its fence status flag, and let UMD side aware that this
fence signaling is not due to job complete but job hang.

2:if gpu reset cause all video memory lost, we need introduce
a new policy to implement TDR, like drop all jobs not yet
signaled, and all IOCTL on this device will return ERROR
DEVICE_LOST.
this will be implemented later.
Signed-off-by: NMonk Liu <Monk.Liu@amd.com>
Reviewed-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

because we don't want to do sriov-gpu-reset under certain
cases, so just split those two funtion and don't invoke
sr-iov one from bare-metal one.

V2:
remove debugfs_gpu_reset routine on SRIOV case.
Signed-off-by: NMonk Liu <Monk.Liu@amd.com>
Reviewed-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

KIQ is used for interaction between driver and
CP, and not exposed to outside client, as such it
doesn't need to be handled by GPU scheduler.
Signed-off-by: NMonk Liu <Monk.Liu@amd.com>
Signed-off-by: NXiangliang Yu <Xiangliang.Yu@amd.com>
Signed-off-by: NTrigger Huang <trigger.huang@amd.com>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Reviewed-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

I plan to usurp the short name of struct fence for a core kernel struct,
and so I need to rename the specialised fence/timeline for DMA
operations to make room.

A consensus was reached in
https://lists.freedesktop.org/archives/dri-devel/2016-July/113083.html
that making clear this fence applies to DMA operations was a good thing.
Since then the patch has grown a bit as usage increases, so hopefully it
remains a good thing!

(v2...: rebase, rerun spatch)
v3: Compile on msm, spotted a manual fixup that I broke.
v4: Try again for msm, sorry Daniel

coccinelle script:
@@

@@
- struct fence
+ struct dma_fence
@@

@@
- struct fence_ops
+ struct dma_fence_ops
@@

@@
- struct fence_cb
+ struct dma_fence_cb
@@

@@
- struct fence_array
+ struct dma_fence_array
@@

@@
- enum fence_flag_bits
+ enum dma_fence_flag_bits
@@

@@
(
- fence_init
+ dma_fence_init
|
- fence_release
+ dma_fence_release
|
- fence_free
+ dma_fence_free
|
- fence_get
+ dma_fence_get
|
- fence_get_rcu
+ dma_fence_get_rcu
|
- fence_put
+ dma_fence_put
|
- fence_signal
+ dma_fence_signal
|
- fence_signal_locked
+ dma_fence_signal_locked
|
- fence_default_wait
+ dma_fence_default_wait
|
- fence_add_callback
+ dma_fence_add_callback
|
- fence_remove_callback
+ dma_fence_remove_callback
|
- fence_enable_sw_signaling
+ dma_fence_enable_sw_signaling
|
- fence_is_signaled_locked
+ dma_fence_is_signaled_locked
|
- fence_is_signaled
+ dma_fence_is_signaled
|
- fence_is_later
+ dma_fence_is_later
|
- fence_later
+ dma_fence_later
|
- fence_wait_timeout
+ dma_fence_wait_timeout
|
- fence_wait_any_timeout
+ dma_fence_wait_any_timeout
|
- fence_wait
+ dma_fence_wait
|
- fence_context_alloc
+ dma_fence_context_alloc
|
- fence_array_create
+ dma_fence_array_create
|
- to_fence_array
+ to_dma_fence_array
|
- fence_is_array
+ dma_fence_is_array
|
- trace_fence_emit
+ trace_dma_fence_emit
|
- FENCE_TRACE
+ DMA_FENCE_TRACE
|
- FENCE_WARN
+ DMA_FENCE_WARN
|
- FENCE_ERR
+ DMA_FENCE_ERR
)
 (
 ...
 )
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NGustavo Padovan <gustavo.padovan@collabora.co.uk>
Acked-by: NSumit Semwal <sumit.semwal@linaro.org>
Acked-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161025120045.28839-1-chris@chris-wilson.co.uk

To free fences, call_rcu() is used, which calls amdgpu_fence_free()
after a grace period. During teardown, there is no guarantee all
callbacks have finished, so amdgpu_fence_slab may be destroyed before
all fences have been freed. If we are lucky, this results in some slab
warnings, if not, we get a crash in one of rcu threads because callback
is called after amdgpu has already been unloaded.

Fix it with a rcu_barrier().

Fixes: b4413535 ("drm/amdgpu: RCU protected amdgpu_fence_release")
Acked-by: NChunming Zhou <david1.zhou@amd.com>
Reviewed-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NGrazvydas Ignotas <notasas@gmail.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Right now it's possible to trigger fence_drv.fences[] dereference after
the array has been freed. While the real problem is elsewhere, this still
results in confusing errors that depend on how the freed memory was
reused (I've seen "kernel tried to execute NX-protected page"), it's
better to clear them and get NULL dereference so that it's obvious what's
going wrong.
Signed-off-by: NGrazvydas Ignotas <notasas@gmail.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

A little fallout from "drm/amdgpu: sanitize fence numbers", we
sometimes need to signal all fences in the ring.
Signed-off-by: NChristian König <christian.koenig@amd.com>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Reviewed-by: NChunming Zhou <david1.zhou@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Looks like the VCE block sometimes still sends nonsense
fence numbers on startup.
Signed-off-by: NChristian König <christian.koenig@amd.com>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Using wrong counter for walking fences.  Fixes
a crash when unloading the driver.
Signed-off-by: NMonk Liu <Monk.Liu@amd.com>
Reviewed-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

This avoids problems with multiple GPUs.  For example,
if the first GPU failed before amdgpu_fence_init() was
called, amdgpu_fence_slab_ref is still 0 and it will
get decremented in amdgpu_fence_driver_fini().  This
will lead to a crash during init of the second GPU since
amdgpu_fence_slab_ref is not 0.

v2: add functions for init/exit instead of
    moving the variables into the driver.
Signed-off-by: NRex Zhu <Rex.Zhu@amd.com>
Reviewed-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

The rcu_assign_pointer() ensures that the initialization of a structure
is carried out before storing a pointer to that structre. It is always
safe to use RCU_INIT_POINTER() to NULL a pointer, instead of
rcu_assign_pointer().
This results in slightly smaller/faster code.

The following semantic patch was used:
<smpl>

@@
@@

- rcu_assign_pointer
+ RCU_INIT_POINTER
  (..., NULL)

</smpl>
Reviewed-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NMuhammad Falak R Wani <falakreyaz@gmail.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

we introduced vmid fence, so one hw submission could produce two fences.
Signed-off-by: NChunming Zhou <David1.Zhou@amd.com>
Reviewed-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

All these are compile time constand and the
drm_debugfs_create/remove_files functions take a const
pointer argument.
Reviewed-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NNils Wallménius <nils.wallmenius@gmail.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

since the rcu slot was initialized to be num_hw_submission,
if command submission doesn't use scheduler, this limitation
will be invalid like uvd test.
Signed-off-by: NChunming Zhou <David1.Zhou@amd.com>
Reviewed-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

We don't need to extend them to 64bits any more, so avoid the extra overhead.

v2: update commit message.
Signed-off-by: NChristian König <christian.koenig@amd.com>
Acked-by: NAlex Deucher <alexander.deucher@amd.com>
Reviewed-by: NChunming Zhou <david1.zhou@amd.com>

It's just overhead to check the fence value
when we signal them directly anyway.
Signed-off-by: NChristian König <christian.koenig@amd.com>
Acked-by: NAlex Deucher <alexander.deucher@amd.com>
Reviewed-by: NChunming Zhou <david1.zhou@amd.com>

Amdgpu doesn't support using scratch registers for fences any more.
So we won't see values like 0xdeadbeef as fence value any more.

v2: reschedule timer even if no change detected
Signed-off-by: NChristian König <christian.koenig@amd.com>
Acked-by: NAlex Deucher <alexander.deucher@amd.com>
Reviewed-by: NChunming Zhou <david1.zhou@amd.com>

Because of the scheduler we need to signal all fences immediately
anyway, so try to avoid the waitqueue overhead.
Signed-off-by: NChristian König <christian.koenig@amd.com>
Acked-by: NAlex Deucher <alexander.deucher@amd.com>
Reviewed-by: NChunming Zhou <david1.zhou@amd.com>

Just wait for last fence instead of waiting for the sequence manually.

v2: don't use amdgpu_sched_jobs for the mask
Signed-off-by: NChristian König <christian.koenig@amd.com>
Acked-by: NAlex Deucher <alexander.deucher@amd.com>
Reviewed-by: NChunming Zhou <david1.zhou@amd.com>

Just keep all HW fences in a RCU protected array as a
first step to replace the wait queue.

v2: update commit message, move fixes into separate patch.
Signed-off-by: NChristian König <christian.koenig@amd.com>
Acked-by: NAlex Deucher <alexander.deucher@amd.com>
Reviewed-by: NChunming Zhou <david1.zhou@amd.com>

Make this a parameter instead of using the global variable directly.
Signed-off-by: NChristian König <christian.koenig@amd.com>
Acked-by: NAlex Deucher <alexander.deucher@amd.com>
Reviewed-by: NChunming Zhou <david1.zhou@amd.com>

Fences must be freed RCU protected, otherwise the reservation_object_*_rcu()
functions can run into problems.
Signed-off-by: NChristian König <christian.koenig@amd.com>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>

No need to keep the two separate any more.
Signed-off-by: NChristian König <christian.koenig@amd.com>
Reviewed-by: NChunming Zhou <david1.zhou@amd.com>

The comment about the loop counter was never valid, even when you have
multiple threads this loop only runs as long as the sequence increases.
Signed-off-by: NChristian König <christian.koenig@amd.com>
Reviewed-by: NChunming Zhou <david1.zhou@amd.com>

No need to have that in the header file any more.
Signed-off-by: NChristian König <christian.koenig@amd.com>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Not used any more.
Signed-off-by: NChristian König <christian.koenig@amd.com>
Acked-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Try to avoid using the hardware specific fences even more.
Signed-off-by: NChristian König <christian.koenig@amd.com>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Reviewed-by: NChunming Zhou <david1.zhou@amd.com>

Not used any more since we now always use the sheduler.
Signed-off-by: NChristian König <christian.koenig@amd.com>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Reviewed-by: NChunming Zhou <david1.zhou@amd.com>

wait_event() never returns before the fence was signaled.
Signed-off-by: NChristian König <christian.koenig@amd.com>
Acked-by: NAlex Deucher <alexander.deucher@amd.com>

It's not needed any more because all access goes through the scheduler now.

v2: Update commit message.
Signed-off-by: NChristian König <christian.koenig@amd.com>
Reviewed-by: NChunming Zhou <david1.zhou@amd.com>
Acked-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Ported from similar code in radeon.
Reviewed-by: NJunwei Zhang <Jerry.Zhang@amd.com>
Reviewed-by: NChristian König <christian.koenig@amd.com>
Reviewed-by: NKen Wang <Qingqing.Wang@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Not used any more without semaphores
Signed-off-by: NChristian König <christian.koenig@amd.com>
Reviewed-by: NChunming Zhou <david1.zhou@amd.com>
Acked-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Non-scheduler code is longer supported.

v2: agd: rebased on upstream
Signed-off-by: NChunming Zhou <David1.Zhou@amd.com>
Reviewed-by: NKen Wang  <Qingqing.Wang@amd.com>
Reviewed-by: NMonk Liu <monk.liu@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Change-Id: I5ad8dd156ccf27a6f18004aa0a215a0925b6e67b
Signed-off-by: NChunming Zhou <David1.Zhou@amd.com>
Reviewed-by: NChristian König <christian.koenig@amd.com>

Less overhead than a work item and also adds proper cleanup handling.
Signed-off-by: NChristian König <christian.koenig@amd.com>
Reviewed-by: NChunming Zhou <david1.zhou@amd.com>
Acked-by: NAlex Deucher <alexander.deucher@amd.com>

Mostly unused and replaced by the common trace points.
Signed-off-by: NChristian König <christian.koenig@amd.com>
Reviewed-by: NChunming Zhou <david1.zhou@amd.com>
Acked-by: NAlex Deucher <alexander.deucher@amd.com>

And also add some missing function documentation. No functional change.
Signed-off-by: NChristian König <christian.koenig@amd.com>
Reviewed-by: NChunming Zhou <david1.zhou@amd.com>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>

Interrupts are notorious unreliable, enable the fallback at
a couple of more places.
Signed-off-by: NChristian König <christian.koenig@amd.com>
Reviewed-by: NChunming Zhou <david1.zhou@amd.com>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>

Just move the remaining users to fence_put/get.
Signed-off-by: NChristian König <christian.koenig@amd.com>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>