diff options
| author | Chris Wilson <chris@chris-wilson.co.uk> | 2019-04-03 09:21:32 +0100 |
|---|---|---|
| committer | Chris Wilson <chris@chris-wilson.co.uk> | 2019-04-05 10:39:17 +0100 |
| commit | b66ea2c2cf59b80c38a14127fafb49fdf0df9180 (patch) | |
| tree | bbb483368908e89aab28cf84b74870650e3ca0b8 | |
| parent | c2400ec3b6d15beea34d652ee18962ed13433528 (diff) | |
drm/i915: Use lockdep_pin_lock() over the construction of the request
During request construction, we take the timeline->mutex to ensure
exclusive access to the ringbuffer (for command emission) and the
timeline itself (for command ordering). The timeline->mutex should not
be dropped by callers until we release it in i915_request_add().
lockdep provides a pin/unpin lock facility to detect accidental unlocks
inside critical sections, so put it to use for request construction.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190403082132.327-1-chris@chris-wilson.co.uk
| -rw-r--r-- | drivers/gpu/drm/i915/i915_request.c | 5 | ||||
| -rw-r--r-- | drivers/gpu/drm/i915/i915_request.h | 10 |
2 files changed, 15 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/i915_request.c b/drivers/gpu/drm/i915/i915_request.c index 82094b9f5ba7..7f8a4eba98b8 100644 --- a/drivers/gpu/drm/i915/i915_request.c +++ b/drivers/gpu/drm/i915/i915_request.c @@ -751,7 +751,10 @@ i915_request_alloc(struct intel_engine_cs *engine, struct i915_gem_context *ctx) rq->infix = rq->ring->emit; /* end of header; start of user payload */ /* Check that we didn't interrupt ourselves with a new request */ + lockdep_assert_held(&rq->timeline->mutex); GEM_BUG_ON(rq->timeline->seqno != rq->fence.seqno); + rq->cookie = lockdep_pin_lock(&rq->timeline->mutex); + return rq; err_unwind: @@ -1070,6 +1073,8 @@ void i915_request_add(struct i915_request *request) engine->name, request->fence.context, request->fence.seqno); lockdep_assert_held(&request->timeline->mutex); + lockdep_unpin_lock(&request->timeline->mutex, request->cookie); + trace_i915_request_add(request); /* diff --git a/drivers/gpu/drm/i915/i915_request.h b/drivers/gpu/drm/i915/i915_request.h index cd6c130964cd..875be6f71412 100644 --- a/drivers/gpu/drm/i915/i915_request.h +++ b/drivers/gpu/drm/i915/i915_request.h @@ -26,6 +26,7 @@ #define I915_REQUEST_H #include <linux/dma-fence.h> +#include <linux/lockdep.h> #include "i915_gem.h" #include "i915_scheduler.h" @@ -121,6 +122,15 @@ struct i915_request { unsigned long rcustate; /* + * We pin the timeline->mutex while constructing the request to + * ensure that no caller accidentally drops it during construction. + * The timeline->mutex must be held to ensure that only this caller + * can use the ring and manipulate the associated timeline during + * construction. + */ + struct pin_cookie cookie; + + /* * Fences for the various phases in the request's lifetime. * * The submit fence is used to await upon all of the request's |