Intel i915 GPU driver uses wait-wound mutex to lock multiple GEMs on the attachment to the i915 dma-buf. In order to let all drivers utilize shared wait-wound context during attachment in a general way, make dma-buf core to acquire the ww context internally for the attachment operation and update i915 driver to use the importer's ww context instead of the internal one. >From now on all dma-buf exporters shall use the importer's ww context for the attachment operation. Signed-off-by: Dmitry Osipenko <dmitry.osipenko@xxxxxxxxxxxxx> --- drivers/dma-buf/dma-buf.c | 8 +++++- drivers/gpu/drm/i915/gem/i915_gem_dmabuf.c | 2 +- .../gpu/drm/i915/gem/i915_gem_execbuffer.c | 2 +- drivers/gpu/drm/i915/gem/i915_gem_object.h | 6 ++--- drivers/gpu/drm/i915/i915_gem_evict.c | 2 +- drivers/gpu/drm/i915/i915_gem_ww.c | 26 +++++++++++++++---- drivers/gpu/drm/i915/i915_gem_ww.h | 15 +++++++++-- 7 files changed, 47 insertions(+), 14 deletions(-) diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c index 0ee588276534..37545ecb845a 100644 --- a/drivers/dma-buf/dma-buf.c +++ b/drivers/dma-buf/dma-buf.c @@ -807,6 +807,8 @@ static struct sg_table * __map_dma_buf(struct dma_buf_attachment *attach, * Optionally this calls &dma_buf_ops.attach to allow device-specific attach * functionality. * + * Exporters shall use ww_ctx acquired by this function. + * * Returns: * * A pointer to newly created &dma_buf_attachment on success, or a negative @@ -822,6 +824,7 @@ dma_buf_dynamic_attach_unlocked(struct dma_buf *dmabuf, struct device *dev, void *importer_priv) { struct dma_buf_attachment *attach; + struct ww_acquire_ctx ww_ctx; int ret; if (WARN_ON(!dmabuf || !dev)) @@ -841,7 +844,8 @@ dma_buf_dynamic_attach_unlocked(struct dma_buf *dmabuf, struct device *dev, attach->importer_ops = importer_ops; attach->importer_priv = importer_priv; - dma_resv_lock(dmabuf->resv, NULL); + ww_acquire_init(&ww_ctx, &reservation_ww_class); + dma_resv_lock(dmabuf->resv, &ww_ctx); if (dmabuf->ops->attach) { ret = dmabuf->ops->attach(dmabuf, attach); @@ -876,11 +880,13 @@ dma_buf_dynamic_attach_unlocked(struct dma_buf *dmabuf, struct device *dev, } dma_resv_unlock(dmabuf->resv); + ww_acquire_fini(&ww_ctx); return attach; err_attach: dma_resv_unlock(attach->dmabuf->resv); + ww_acquire_fini(&ww_ctx); kfree(attach); return ERR_PTR(ret); diff --git a/drivers/gpu/drm/i915/gem/i915_gem_dmabuf.c b/drivers/gpu/drm/i915/gem/i915_gem_dmabuf.c index c199bf71c373..9173f0232b16 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_dmabuf.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_dmabuf.c @@ -173,7 +173,7 @@ static int i915_gem_dmabuf_attach(struct dma_buf *dmabuf, if (!i915_gem_object_can_migrate(obj, INTEL_REGION_SMEM)) return -EOPNOTSUPP; - for_i915_gem_ww(&ww, err, true) { + for_i915_dmabuf_ww(&ww, dmabuf, err, true) { err = i915_gem_object_migrate(obj, &ww, INTEL_REGION_SMEM); if (err) continue; diff --git a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c index 30fe847c6664..ad7d602fc43a 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c @@ -3409,7 +3409,7 @@ i915_gem_do_execbuffer(struct drm_device *dev, goto err_vma; } - ww_acquire_done(&eb.ww.ctx); + ww_acquire_done(eb.ww.ctx); eb_capture_stage(&eb); out_fence = eb_requests_create(&eb, in_fence, out_fence_fd); diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object.h b/drivers/gpu/drm/i915/gem/i915_gem_object.h index e11d82a9f7c3..5ae38f94a5c7 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_object.h +++ b/drivers/gpu/drm/i915/gem/i915_gem_object.h @@ -178,9 +178,9 @@ static inline int __i915_gem_object_lock(struct drm_i915_gem_object *obj, int ret; if (intr) - ret = dma_resv_lock_interruptible(obj->base.resv, ww ? &ww->ctx : NULL); + ret = dma_resv_lock_interruptible(obj->base.resv, ww ? ww->ctx : NULL); else - ret = dma_resv_lock(obj->base.resv, ww ? &ww->ctx : NULL); + ret = dma_resv_lock(obj->base.resv, ww ? ww->ctx : NULL); if (!ret && ww) { i915_gem_object_get(obj); @@ -216,7 +216,7 @@ static inline bool i915_gem_object_trylock(struct drm_i915_gem_object *obj, if (!ww) return dma_resv_trylock(obj->base.resv); else - return ww_mutex_trylock(&obj->base.resv->lock, &ww->ctx); + return ww_mutex_trylock(&obj->base.resv->lock, ww->ctx); } static inline void i915_gem_object_unlock(struct drm_i915_gem_object *obj) diff --git a/drivers/gpu/drm/i915/i915_gem_evict.c b/drivers/gpu/drm/i915/i915_gem_evict.c index f025ee4fa526..047f72e32d47 100644 --- a/drivers/gpu/drm/i915/i915_gem_evict.c +++ b/drivers/gpu/drm/i915/i915_gem_evict.c @@ -458,7 +458,7 @@ int i915_gem_evict_vm(struct i915_address_space *vm, struct i915_gem_ww_ctx *ww) * need the object ref. */ if (dying_vma(vma) || - (ww && (dma_resv_locking_ctx(vma->obj->base.resv) == &ww->ctx))) { + (ww && (dma_resv_locking_ctx(vma->obj->base.resv) == ww->ctx))) { __i915_vma_pin(vma); list_add(&vma->evict_link, &locked_eviction_list); continue; diff --git a/drivers/gpu/drm/i915/i915_gem_ww.c b/drivers/gpu/drm/i915/i915_gem_ww.c index 3f6ff139478e..c47898993c7d 100644 --- a/drivers/gpu/drm/i915/i915_gem_ww.c +++ b/drivers/gpu/drm/i915/i915_gem_ww.c @@ -6,12 +6,20 @@ #include "i915_gem_ww.h" #include "gem/i915_gem_object.h" -void i915_gem_ww_ctx_init(struct i915_gem_ww_ctx *ww, bool intr) +void i915_gem_ww_ctx_prep(struct i915_gem_ww_ctx *ww, + struct ww_acquire_ctx *ww_ctx, + bool intr) { - ww_acquire_init(&ww->ctx, &reservation_ww_class); INIT_LIST_HEAD(&ww->obj_list); ww->intr = intr; ww->contended = NULL; + ww->ctx = ww_ctx; +} + +void i915_gem_ww_ctx_init(struct i915_gem_ww_ctx *ww, bool intr) +{ + ww_acquire_init(&ww->ww_ctx, &reservation_ww_class); + i915_gem_ww_ctx_prep(ww, &ww->ww_ctx, intr); } static void i915_gem_ww_ctx_unlock_all(struct i915_gem_ww_ctx *ww) @@ -36,7 +44,15 @@ void i915_gem_ww_ctx_fini(struct i915_gem_ww_ctx *ww) { i915_gem_ww_ctx_unlock_all(ww); WARN_ON(ww->contended); - ww_acquire_fini(&ww->ctx); + + if (ww->ctx == &ww->ww_ctx) + ww_acquire_fini(ww->ctx); +} + +void i915_gem_ww_ctx_fini2(struct i915_gem_ww_ctx *ww) +{ + i915_gem_ww_ctx_unlock_all(ww); + WARN_ON(ww->contended); } int __must_check i915_gem_ww_ctx_backoff(struct i915_gem_ww_ctx *ww) @@ -48,9 +64,9 @@ int __must_check i915_gem_ww_ctx_backoff(struct i915_gem_ww_ctx *ww) i915_gem_ww_ctx_unlock_all(ww); if (ww->intr) - ret = dma_resv_lock_slow_interruptible(ww->contended->base.resv, &ww->ctx); + ret = dma_resv_lock_slow_interruptible(ww->contended->base.resv, ww->ctx); else - dma_resv_lock_slow(ww->contended->base.resv, &ww->ctx); + dma_resv_lock_slow(ww->contended->base.resv, ww->ctx); if (!ret) list_add_tail(&ww->contended->obj_link, &ww->obj_list); diff --git a/drivers/gpu/drm/i915/i915_gem_ww.h b/drivers/gpu/drm/i915/i915_gem_ww.h index 86f0fe343de6..e9b0fd4debbf 100644 --- a/drivers/gpu/drm/i915/i915_gem_ww.h +++ b/drivers/gpu/drm/i915/i915_gem_ww.h @@ -8,13 +8,17 @@ #include <drm/drm_drv.h> struct i915_gem_ww_ctx { - struct ww_acquire_ctx ctx; + struct ww_acquire_ctx *ctx; + struct ww_acquire_ctx ww_ctx; struct list_head obj_list; struct drm_i915_gem_object *contended; bool intr; }; -void i915_gem_ww_ctx_init(struct i915_gem_ww_ctx *ctx, bool intr); +void i915_gem_ww_ctx_prep(struct i915_gem_ww_ctx *ww, + struct ww_acquire_ctx *ww_ctx, + bool intr); +void i915_gem_ww_ctx_init(struct i915_gem_ww_ctx *ww, bool intr); void i915_gem_ww_ctx_fini(struct i915_gem_ww_ctx *ctx); int __must_check i915_gem_ww_ctx_backoff(struct i915_gem_ww_ctx *ctx); void i915_gem_ww_unlock_single(struct drm_i915_gem_object *obj); @@ -38,4 +42,11 @@ static inline int __i915_gem_ww_fini(struct i915_gem_ww_ctx *ww, int err) for (i915_gem_ww_ctx_init(_ww, _intr), (_err) = -EDEADLK; \ (_err) == -EDEADLK; \ (_err) = __i915_gem_ww_fini(_ww, _err)) + +#define for_i915_dmabuf_ww(_ww, _dmabuf, _err, _intr) \ + for (i915_gem_ww_ctx_prep(_ww, dma_resv_locking_ctx((_dmabuf)->resv), _intr), \ + (_err) = -EDEADLK; \ + (_err) == -EDEADLK; \ + (_err) = __i915_gem_ww_fini(_ww, _err)) + #endif -- 2.36.1