linux-toradex.git/drivers/dma-buf/sw_sync.c, branch v4.9.113

dma-buf/sw_sync: force signal all unsignaled fences on dying timeline

2017-12-09T21:01:56+00:00

commit ea4d5a270b57fa8d4871f372ca9b97b7697fdfda upstream.

To avoid hanging userspace components that might have been waiting on the
active fences of the destroyed timeline we need to signal with error all
remaining fences on such timeline.

This restore the default behaviour of the Android sw_sync framework, which
Android still relies on. It was broken on the dma fence conversion a few
years ago and never fixed.

v2: Do not bother with cleanup do the list (Chris Wilson)

Reviewed-by: Chris Wilson 
Signed-off-by: Dominik Behr 
Signed-off-by: Gustavo Padovan 
Link: https://patchwork.freedesktop.org/patch/msgid/20170907190246.16425-2-gustavo@padovan.org
[s/dma_fence/fence/g - gregkh]
Cc: Jisheng Zhang 
Signed-off-by: Greg Kroah-Hartman

dma-buf/sw_sync: clean up list before signaling the fence

2017-12-09T21:01:55+00:00

commit 3792b7c1a70815fe4e954221c096f9278638fd21 upstream.

If userspace already dropped its own reference by closing the sw_sync
fence fd we might end up in a deadlock where
dma_fence_is_signaled_locked() will trigger the release of the fence and
thus try to hold the lock to remove the fence from the list.

dma_fence_is_signaled_locked() tries to release/free the fence and hold
the lock in the process.

We fix that by changing the order operation and clean up the list and
rb-tree first.

v2: Drop fence get/put dance and manipulate the list first (Chris Wilson)

Cc: Chris Wilson 
Signed-off-by: Gustavo Padovan 
Reviewed-by: Chris Wilson 
Link: https://patchwork.freedesktop.org/patch/msgid/20170729152217.8362-2-gustavo@padovan.org
[s/dma_fence/fence/g - gregkh]
Cc: Jisheng Zhang 
Signed-off-by: Greg Kroah-Hartman

dma-buf/sw_sync: move timeline_fence_ops around

2017-12-09T21:01:55+00:00

commit 150b6a9d7d6fffb95c0a5349960a10569e8218b5 upstream.

We are going to use timeline_fence_signaled() in a internal function in
the next commit.

Cc: Chris Wilson 
Signed-off-by: Gustavo Padovan 
Reviewed-by: Chris Wilson 
Link: https://patchwork.freedesktop.org/patch/msgid/20170729152217.8362-1-gustavo@padovan.org
[s/dma_fence/fence/g - gregkh]
Cc: Jisheng Zhang 
Signed-off-by: Greg Kroah-Hartman

dma-buf/sw-sync: Use an rbtree to sort fences in the timeline

2017-12-09T21:01:55+00:00

commit f1e8c67123cf171e2b0357e885e426328b241d7d upstream.

Reduce the list iteration when incrementing the timeline by storing the
fences in increasing order.

v2: Prevent spinlock recursion on free during create
v3: Fixup rebase conflict inside comments that escaped the compiler.

Signed-off-by: Chris Wilson 
Cc: Sumit Semwal 
Cc: Sean Paul 
Cc: Gustavo Padovan 
Reviewed-by: Sean Paul 
Signed-off-by: Gustavo Padovan 
Link: http://patchwork.freedesktop.org/patch/msgid/20170629211253.22766-1-chris@chris-wilson.co.uk
[s/dma_fence/fence/g - gregkh]
Cc: Jisheng Zhang 
Signed-off-by: Greg Kroah-Hartman

dma-buf/sw-sync: Fix locking around sync_timeline lists

2017-12-09T21:01:55+00:00

commit d3862e44daa7a0c94d2f6193502a8c49379acfce upstream.

The sync_pt were not adding themselves atomically to the timeline lists,
corruption imminent.  Only a single list is required to track the
unsignaled sync_pt, so reduce it and rename the lock more appropriately
along with using idiomatic names to distinguish a list from links along
it.

v2: Prevent spinlock recursion on free during create (next patch) and
fixup crossref in kerneldoc

Signed-off-by: Chris Wilson 
Cc: Sumit Semwal 
Cc: Sean Paul 
Cc: Gustavo Padovan 
Reviewed-by: Sean Paul 
Signed-off-by: Gustavo Padovan 
Link: http://patchwork.freedesktop.org/patch/msgid/20170629210532.5617-1-chris@chris-wilson.co.uk
[s/dma_fence/fence/g - gregkh]
Cc: Jisheng Zhang 
Signed-off-by: Greg Kroah-Hartman

dma-buf/sw-sync: sync_pt is private and of fixed size

2017-12-09T21:01:55+00:00

commit 3b52ce44e720c240afc4c4b03140d7b7811b23bd upstream.

Since sync_pt is only allocated from a single location and is no longer
the base class for fences (that is struct dma_fence) it no longer needs
a generic unsized allocator.

Signed-off-by: Chris Wilson 
Cc: Sumit Semwal 
Cc: Sean Paul 
Cc: Gustavo Padovan 
Reviewed-by: Sean Paul 
Signed-off-by: Gustavo Padovan 
Link: http://patchwork.freedesktop.org/patch/msgid/20170629125930.821-5-chris@chris-wilson.co.uk
[s/dma_fence/fence/g - gregkh]
Cc: Jisheng Zhang 
Signed-off-by: Greg Kroah-Hartman

dma-buf/sw-sync: Reduce irqsave/irqrestore from known context

2017-12-09T21:01:55+00:00

commit a6aa8fca4d792c72947e341d7842d2f700534335 upstream.

If we know the context under which we are called, then we can use the
simpler form of spin_lock_irq (saving the save/restore).

Signed-off-by: Chris Wilson 
Cc: Sumit Semwal 
Cc: Sean Paul 
Cc: Gustavo Padovan 
Reviewed-by: Sean Paul 
Signed-off-by: Gustavo Padovan 
Link: http://patchwork.freedesktop.org/patch/msgid/20170629125930.821-4-chris@chris-wilson.co.uk
[s/dma_fence/fence/g - gregkh]
Cc: Jisheng Zhang 
Signed-off-by: Greg Kroah-Hartman

dma-buf/sw-sync: Prevent user overflow on timeline advance

2017-12-09T21:01:55+00:00

commit 8f66d3aa1735bc95ae58d846a157357e8d41abb8 upstream.

The timeline is u32, which limits any single advance to INT_MAX so that
we can detect all fences that need signaling.

Signed-off-by: Chris Wilson 
Cc: Sumit Semwal 
Cc: Sean Paul 
Cc: Gustavo Padovan 
Reviewed-by: Sean Paul 
Signed-off-by: Gustavo Padovan 
Link: http://patchwork.freedesktop.org/patch/msgid/20170629125930.821-3-chris@chris-wilson.co.uk
[s/dma_fence/fence/g - gregkh]
Cc: Jisheng Zhang 
Signed-off-by: Greg Kroah-Hartman

dma-buf/sw-sync: Fix the is-signaled test to handle u32 wraparound

2017-12-09T21:01:55+00:00

commit 61894b02716f122dd7662d5d89f5b2245ca551e2 upstream.

Use the canonical __dma_fence_is_later() to compare the fence seqno
against the timeline seqno to check if the fence is signaled.

Signed-off-by: Chris Wilson 
Cc: Sumit Semwal 
Cc: Sean Paul 
Cc: Gustavo Padovan 
Reviewed-by: Sean Paul 
Signed-off-by: Gustavo Padovan 
Link: http://patchwork.freedesktop.org/patch/msgid/20170629125930.821-2-chris@chris-wilson.co.uk
[s/dma_fence/fence/g - gregkh]
Cc: Jisheng Zhang 
Signed-off-by: Greg Kroah-Hartman

dma-buf/sw_sync: de-stage SW_SYNC

2016-08-15T14:41:46+00:00

SW_SYNC allows to run tests on the sync_file framework via debugfs on

/sync/sw_sync

Opening and closing the file triggers creation and release of a sync
timeline. To create fences on this timeline the SW_SYNC_IOC_CREATE_FENCE
ioctl should be used. To increment the timeline value use SW_SYNC_IOC_INC.

Also it exports Sync information on

/sync/info

Signed-off-by: Gustavo Padovan 
Reviewed-by: Eric Engestrom 
Signed-off-by: Greg Kroah-Hartman