Re: [PATCH 48/53] drm/i915: Update intel_ring_begin() to take a request structure

Tomas Elf
2015-03-09T22:40:29Z

On 19/02/2015 17:18, John.C.Harrison@Intel.com wrote:
> From: John Harrison <John.C.Harrison@Intel.com>
>
> Now that everything above has been converted to use requests, intel_ring_begin()
> can be updated to take a request instead of a ring. This also means that it no
> longer needs to lazily allocate a request if no-one happens to have done it
> earlier.
>
> For: VIZ-5115
> Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
> ---
> drivers/gpu/drm/i915/i915_gem.c | 2 +-
> drivers/gpu/drm/i915/i915_gem_context.c | 2 +-
> drivers/gpu/drm/i915/i915_gem_execbuffer.c | 8 ++--
> drivers/gpu/drm/i915/i915_gem_gtt.c | 6 +--
> drivers/gpu/drm/i915/intel_display.c | 10 ++--
> drivers/gpu/drm/i915/intel_overlay.c | 8 ++--
> drivers/gpu/drm/i915/intel_pm.c | 2 +-
> drivers/gpu/drm/i915/intel_ringbuffer.c | 72 +++++++++++++---------------
> drivers/gpu/drm/i915/intel_ringbuffer.h | 2 +-
> 9 files changed, 54 insertions(+), 58 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
> index b5613ff..60f6671 100644
> --- a/drivers/gpu/drm/i915/i915_gem.c
> +++ b/drivers/gpu/drm/i915/i915_gem.c
> @@ -4656,7 +4656,7 @@ int i915_gem_l3_remap(struct drm_i915_gem_request *req, int slice)
> if (!HAS_L3_DPF(dev) || !remap_info)
> return 0;
>
> - ret = intel_ring_begin(ring, GEN7_L3LOG_SIZE / 4 * 3);
> + ret = intel_ring_begin(req, GEN7_L3LOG_SIZE / 4 * 3);
> if (ret)
> return ret;
>
> diff --git a/drivers/gpu/drm/i915/i915_gem_context.c b/drivers/gpu/drm/i915/i915_gem_context.c
> index 384f481..e348424 100644
> --- a/drivers/gpu/drm/i915/i915_gem_context.c
> +++ b/drivers/gpu/drm/i915/i915_gem_context.c
> @@ -503,7 +503,7 @@ mi_set_context(struct drm_i915_gem_request *req, u32 hw_flags)
> if (INTEL_INFO(ring->dev)->gen >= 7)
> len += 2 + (num_rings ? 4*num_rings + 2 : 0);
>
> - ret = intel_ring_begin(ring, len);
> + ret = intel_ring_begin(req, len);
> if (ret)
> return ret;
>
> diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
> index 8b4f8a9..6a703e6 100644
> --- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c
> +++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
> @@ -1013,7 +1013,7 @@ i915_reset_gen7_sol_offsets(struct drm_device *dev,
> return -EINVAL;
> }
>
> - ret = intel_ring_begin(ring, 4 * 3);
> + ret = intel_ring_begin(req, 4 * 3);
> if (ret)
> return ret;
>
> @@ -1044,7 +1044,7 @@ i915_emit_box(struct drm_i915_gem_request *req,
> }
>
> if (INTEL_INFO(ring->dev)->gen >= 4) {
> - ret = intel_ring_begin(ring, 4);
> + ret = intel_ring_begin(req, 4);
> if (ret)
> return ret;
>
> @@ -1053,7 +1053,7 @@ i915_emit_box(struct drm_i915_gem_request *req,
> intel_ring_emit(ring, ((box->x2 - 1) & 0xffff) | (box->y2 - 1) << 16);
> intel_ring_emit(ring, DR4);
> } else {
> - ret = intel_ring_begin(ring, 6);
> + ret = intel_ring_begin(req, 6);
> if (ret)
> return ret;
>
> @@ -1235,7 +1235,7 @@ i915_gem_ringbuffer_submission(struct i915_execbuffer_params *params,
>
> if (ring == &dev_priv->ring[RCS] &&
> instp_mode != dev_priv->relative_constants_mode) {
> - ret = intel_ring_begin(ring, 4);
> + ret = intel_ring_begin(params->request, 4);
> if (ret)
> goto error;
>
> diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
> index a1af644..0445278 100644
> --- a/drivers/gpu/drm/i915/i915_gem_gtt.c
> +++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
> @@ -288,7 +288,7 @@ static int gen8_write_pdp(struct drm_i915_gem_request *req, unsigned entry,
>
> BUG_ON(entry >= 4);
>
> - ret = intel_ring_begin(ring, 6);
> + ret = intel_ring_begin(req, 6);
> if (ret)
> return ret;
>
> @@ -788,7 +788,7 @@ static int hsw_mm_switch(struct i915_hw_ppgtt *ppgtt,
> if (ret)
> return ret;
>
> - ret = intel_ring_begin(ring, 6);
> + ret = intel_ring_begin(req, 6);
> if (ret)
> return ret;
>
> @@ -825,7 +825,7 @@ static int gen7_mm_switch(struct i915_hw_ppgtt *ppgtt,
> if (ret)
> return ret;
>
> - ret = intel_ring_begin(ring, 6);
> + ret = intel_ring_begin(req, 6);
> if (ret)
> return ret;
>
> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> index 7962946..6901e9a 100644
> --- a/drivers/gpu/drm/i915/intel_display.c
> +++ b/drivers/gpu/drm/i915/intel_display.c
> @@ -9259,7 +9259,7 @@ static int intel_gen2_queue_flip(struct drm_device *dev,
> u32 flip_mask;
> int ret;
>
> - ret = intel_ring_begin(ring, 6);
> + ret = intel_ring_begin(req, 6);
> if (ret)
> return ret;
>
> @@ -9294,7 +9294,7 @@ static int intel_gen3_queue_flip(struct drm_device *dev,
> u32 flip_mask;
> int ret;
>
> - ret = intel_ring_begin(ring, 6);
> + ret = intel_ring_begin(req, 6);
> if (ret)
> return ret;
>
> @@ -9327,7 +9327,7 @@ static int intel_gen4_queue_flip(struct drm_device *dev,
> uint32_t pf, pipesrc;
> int ret;
>
> - ret = intel_ring_begin(ring, 4);
> + ret = intel_ring_begin(req, 4);
> if (ret)
> return ret;
>
> @@ -9366,7 +9366,7 @@ static int intel_gen6_queue_flip(struct drm_device *dev,
> uint32_t pf, pipesrc;
> int ret;
>
> - ret = intel_ring_begin(ring, 4);
> + ret = intel_ring_begin(req, 4);
> if (ret)
> return ret;
>
> @@ -9442,7 +9442,7 @@ static int intel_gen7_queue_flip(struct drm_device *dev,
> if (ret)
> return ret;
>
> - ret = intel_ring_begin(ring, len);
> + ret = intel_ring_begin(req, len);
> if (ret)
> return ret;
>
> diff --git a/drivers/gpu/drm/i915/intel_overlay.c b/drivers/gpu/drm/i915/intel_overlay.c
> index 228c9d1..1fb7653 100644
> --- a/drivers/gpu/drm/i915/intel_overlay.c
> +++ b/drivers/gpu/drm/i915/intel_overlay.c
> @@ -251,7 +251,7 @@ static int intel_overlay_on(struct intel_overlay *overlay)
> if (ret)
> return ret;
>
> - ret = intel_ring_begin(ring, 4);
> + ret = intel_ring_begin(req, 4);
> if (ret) {
> i915_gem_request_unreference(req);
> return ret;
> @@ -292,7 +292,7 @@ static int intel_overlay_continue(struct intel_overlay *overlay,
> if (ret)
> return ret;
>
> - ret = intel_ring_begin(ring, 2);
> + ret = intel_ring_begin(req, 2);
> if (ret) {
> i915_gem_request_unreference(req);
> return ret;
> @@ -359,7 +359,7 @@ static int intel_overlay_off(struct intel_overlay *overlay)
> if (ret)
> return ret;
>
> - ret = intel_ring_begin(ring, 6);
> + ret = intel_ring_begin(req, 6);
> if (ret) {
> i915_gem_request_unreference(req);
> return ret;
> @@ -434,7 +434,7 @@ static int intel_overlay_release_old_vid(struct intel_overlay *overlay)
> if (ret)
> return ret;
>
> - ret = intel_ring_begin(ring, 2);
> + ret = intel_ring_begin(req, 2);
> if (ret) {
> i915_gem_request_unreference(req);
> return ret;
> diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
> index 6594a52..cc22536 100644
> --- a/drivers/gpu/drm/i915/intel_pm.c
> +++ b/drivers/gpu/drm/i915/intel_pm.c
> @@ -5012,7 +5012,7 @@ static void ironlake_enable_rc6(struct drm_device *dev)
> * GPU can automatically power down the render unit if given a page
> * to save state.
> */
> - ret = intel_ring_begin(ring, 6);
> + ret = intel_ring_begin(req, 6);
> if (ret)
> goto err;
>
> diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
> index 109f283..5eef02e 100644
> --- a/drivers/gpu/drm/i915/intel_ringbuffer.c
> +++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
> @@ -106,7 +106,7 @@ gen2_render_ring_flush(struct drm_i915_gem_request *req,
> if (invalidate_domains & I915_GEM_DOMAIN_SAMPLER)
> cmd |= MI_READ_FLUSH;
>
> - ret = intel_ring_begin(ring, 2);
> + ret = intel_ring_begin(req, 2);
> if (ret)
> return ret;
>
> @@ -165,7 +165,7 @@ gen4_render_ring_flush(struct drm_i915_gem_request *req,
> (IS_G4X(dev) || IS_GEN5(dev)))
> cmd |= MI_INVALIDATE_ISP;
>
> - ret = intel_ring_begin(ring, 2);
> + ret = intel_ring_begin(req, 2);
> if (ret)
> return ret;
>
> @@ -220,8 +220,7 @@ intel_emit_post_sync_nonzero_flush(struct drm_i915_gem_request *req)
> u32 scratch_addr = ring->scratch.gtt_offset + 2 * CACHELINE_BYTES;
> int ret;
>
> -
> - ret = intel_ring_begin(ring, 6);
> + ret = intel_ring_begin(req, 6);
> if (ret)
> return ret;
>
> @@ -234,7 +233,7 @@ intel_emit_post_sync_nonzero_flush(struct drm_i915_gem_request *req)
> intel_ring_emit(ring, MI_NOOP);
> intel_ring_advance(ring);
>
> - ret = intel_ring_begin(ring, 6);
> + ret = intel_ring_begin(req, 6);
> if (ret)
> return ret;
>
> @@ -289,7 +288,7 @@ gen6_render_ring_flush(struct drm_i915_gem_request *req,
> flags |= PIPE_CONTROL_QW_WRITE | PIPE_CONTROL_CS_STALL;
> }
>
> - ret = intel_ring_begin(ring, 4);
> + ret = intel_ring_begin(req, 4);
> if (ret)
> return ret;
>
> @@ -308,7 +307,7 @@ gen7_render_ring_cs_stall_wa(struct drm_i915_gem_request *req)
> struct intel_engine_cs *ring = req->ring;
> int ret;
>
> - ret = intel_ring_begin(ring, 4);
> + ret = intel_ring_begin(req, 4);
> if (ret)
> return ret;
>
> @@ -330,7 +329,7 @@ static int gen7_ring_fbc_flush(struct drm_i915_gem_request *req, u32 value)
> if (!ring->fbc_dirty)
> return 0;
>
> - ret = intel_ring_begin(ring, 6);
> + ret = intel_ring_begin(req, 6);
> if (ret)
> return ret;
> /* WaFbcNukeOn3DBlt:ivb/hsw */
> @@ -395,7 +394,7 @@ gen7_render_ring_flush(struct drm_i915_gem_request *req,
> gen7_render_ring_cs_stall_wa(req);
> }
>
> - ret = intel_ring_begin(ring, 4);
> + ret = intel_ring_begin(req, 4);
> if (ret)
> return ret;
>
> @@ -418,7 +417,7 @@ gen8_emit_pipe_control(struct drm_i915_gem_request *req,
> struct intel_engine_cs *ring = req->ring;
> int ret;
>
> - ret = intel_ring_begin(ring, 6);
> + ret = intel_ring_begin(req, 6);
> if (ret)
> return ret;
>
> @@ -760,7 +759,7 @@ static int intel_ring_workarounds_emit(struct drm_i915_gem_request *req)
> if (ret)
> return ret;
>
> - ret = intel_ring_begin(ring, (w->count * 2 + 2));
> + ret = intel_ring_begin(req, (w->count * 2 + 2));
> if (ret)
> return ret;
>
> @@ -1119,7 +1118,7 @@ static int gen8_rcs_signal(struct drm_i915_gem_request *signaller_req,
> num_dwords += (num_rings-1) * MBOX_UPDATE_DWORDS;
> #undef MBOX_UPDATE_DWORDS
>
> - ret = intel_ring_begin(signaller, num_dwords);
> + ret = intel_ring_begin(signaller_req, num_dwords);
> if (ret)
> return ret;
>
> @@ -1160,7 +1159,7 @@ static int gen8_xcs_signal(struct drm_i915_gem_request *signaller_req,
> num_dwords += (num_rings-1) * MBOX_UPDATE_DWORDS;
> #undef MBOX_UPDATE_DWORDS
>
> - ret = intel_ring_begin(signaller, num_dwords);
> + ret = intel_ring_begin(signaller_req, num_dwords);
> if (ret)
> return ret;
>
> @@ -1199,7 +1198,7 @@ static int gen6_signal(struct drm_i915_gem_request *signaller_req,
> num_dwords += round_up((num_rings-1) * MBOX_UPDATE_DWORDS, 2);
> #undef MBOX_UPDATE_DWORDS
>
> - ret = intel_ring_begin(signaller, num_dwords);
> + ret = intel_ring_begin(signaller_req, num_dwords);
> if (ret)
> return ret;
>
> @@ -1237,7 +1236,7 @@ gen6_add_request(struct drm_i915_gem_request *req)
> if (ring->semaphore.signal)
> ret = ring->semaphore.signal(req, 4);
> else
> - ret = intel_ring_begin(ring, 4);
> + ret = intel_ring_begin(req, 4);
>
> if (ret)
> return ret;
> @@ -1275,7 +1274,7 @@ gen8_ring_sync(struct drm_i915_gem_request *waiter_req,
> struct drm_i915_private *dev_priv = waiter->dev->dev_private;
> int ret;
>
> - ret = intel_ring_begin(waiter, 4);
> + ret = intel_ring_begin(waiter_req, 4);
> if (ret)
> return ret;
>
> @@ -1312,7 +1311,7 @@ gen6_ring_sync(struct drm_i915_gem_request *waiter_req,
>
> WARN_ON(wait_mbox == MI_SEMAPHORE_SYNC_INVALID);
>
> - ret = intel_ring_begin(waiter, 4);
> + ret = intel_ring_begin(waiter_req, 4);
> if (ret)
> return ret;
>
> @@ -1357,7 +1356,7 @@ pc_render_add_request(struct drm_i915_gem_request *req)
> * incoherence by flushing the 6 PIPE_NOTIFY buffers out to
> * memory before requesting an interrupt.
> */
> - ret = intel_ring_begin(ring, 32);
> + ret = intel_ring_begin(req, 32);
> if (ret)
> return ret;
>
> @@ -1542,7 +1541,7 @@ bsd_ring_flush(struct drm_i915_gem_request *req,
> struct intel_engine_cs *ring = req->ring;
> int ret;
>
> - ret = intel_ring_begin(ring, 2);
> + ret = intel_ring_begin(req, 2);
> if (ret)
> return ret;
>
> @@ -1558,7 +1557,7 @@ i9xx_add_request(struct drm_i915_gem_request *req)
> struct intel_engine_cs *ring = req->ring;
> int ret;
>
> - ret = intel_ring_begin(ring, 4);
> + ret = intel_ring_begin(req, 4);
> if (ret)
> return ret;
>
> @@ -1703,7 +1702,7 @@ i965_dispatch_execbuffer(struct drm_i915_gem_request *req,
> struct intel_engine_cs *ring = req->ring;
> int ret;
>
> - ret = intel_ring_begin(ring, 2);
> + ret = intel_ring_begin(req, 2);
> if (ret)
> return ret;
>
> @@ -1731,7 +1730,7 @@ i830_dispatch_execbuffer(struct drm_i915_gem_request *req,
> u32 cs_offset = ring->scratch.gtt_offset;
> int ret;
>
> - ret = intel_ring_begin(ring, 6);
> + ret = intel_ring_begin(req, 6);
> if (ret)
> return ret;
>
> @@ -1748,7 +1747,7 @@ i830_dispatch_execbuffer(struct drm_i915_gem_request *req,
> if (len > I830_BATCH_LIMIT)
> return -ENOSPC;
>
> - ret = intel_ring_begin(ring, 6 + 2);
> + ret = intel_ring_begin(req, 6 + 2);
> if (ret)
> return ret;
>
> @@ -1771,7 +1770,7 @@ i830_dispatch_execbuffer(struct drm_i915_gem_request *req,
> offset = cs_offset;
> }
>
> - ret = intel_ring_begin(ring, 4);
> + ret = intel_ring_begin(req, 4);
> if (ret)
> return ret;
>
> @@ -1793,7 +1792,7 @@ i915_dispatch_execbuffer(struct drm_i915_gem_request *req,
> struct intel_engine_cs *ring = req->ring;
> int ret;
>
> - ret = intel_ring_begin(ring, 2);
> + ret = intel_ring_begin(req, 2);
> if (ret)
> return ret;
>
> @@ -2232,13 +2231,15 @@ static int __intel_ring_prepare(struct intel_engine_cs *ring,
> return 0;
> }
>
> -int intel_ring_begin(struct intel_engine_cs *ring,
> +int intel_ring_begin(struct drm_i915_gem_request *req,
> int num_dwords)
> {
> - struct drm_i915_gem_request *req;
> + struct intel_engine_cs *ring = req->ring;

The WARN_ON below will only fire _after_ we've already gotten a null
pointer exception here at the req->ring dereference. You might want to
rearrange this a bit so that the WARN_ON appears before the dereference.

Thanks,
Tomas

> struct drm_i915_private *dev_priv = ring->dev->dev_private;
> int ret;
>
> + WARN_ON(req == NULL);
> +
> ret = i915_gem_check_wedge(&dev_priv->gpu_error,
> dev_priv->mm.interruptible);
> if (ret)
> @@ -2248,11 +2249,6 @@ int intel_ring_begin(struct intel_engine_cs *ring,
> if (ret)
> return ret;
>
> - /* Preallocate the olr before touching the ring */
> - ret = intel_ring_alloc_request(ring, NULL, &req);
> - if (ret)
> - return ret;
> -
> ring->buffer->space -= num_dwords * sizeof(uint32_t);
> return 0;
> }
> @@ -2268,7 +2264,7 @@ int intel_ring_cacheline_align(struct drm_i915_gem_request *req)
> return 0;
>
> num_dwords = CACHELINE_BYTES / sizeof(uint32_t) - num_dwords;
> - ret = intel_ring_begin(ring, num_dwords);
> + ret = intel_ring_begin(req, num_dwords);
> if (ret)
> return ret;
>
> @@ -2338,7 +2334,7 @@ static int gen6_bsd_ring_flush(struct drm_i915_gem_request *req,
> uint32_t cmd;
> int ret;
>
> - ret = intel_ring_begin(ring, 4);
> + ret = intel_ring_begin(req, 4);
> if (ret)
> return ret;
>
> @@ -2385,7 +2381,7 @@ gen8_ring_dispatch_execbuffer(struct drm_i915_gem_request *req,
> !(dispatch_flags & I915_DISPATCH_SECURE);
> int ret;
>
> - ret = intel_ring_begin(ring, 4);
> + ret = intel_ring_begin(req, 4);
> if (ret)
> return ret;
>
> @@ -2407,7 +2403,7 @@ hsw_ring_dispatch_execbuffer(struct drm_i915_gem_request *req,
> struct intel_engine_cs *ring = req->ring;
> int ret;
>
> - ret = intel_ring_begin(ring, 2);
> + ret = intel_ring_begin(req, 2);
> if (ret)
> return ret;
>
> @@ -2430,7 +2426,7 @@ gen6_ring_dispatch_execbuffer(struct drm_i915_gem_request *req,
> struct intel_engine_cs *ring = req->ring;
> int ret;
>
> - ret = intel_ring_begin(ring, 2);
> + ret = intel_ring_begin(req, 2);
> if (ret)
> return ret;
>
> @@ -2456,7 +2452,7 @@ static int gen6_ring_flush(struct drm_i915_gem_request *req,
> uint32_t cmd;
> int ret;
>
> - ret = intel_ring_begin(ring, 4);
> + ret = intel_ring_begin(req, 4);
> if (ret)
> return ret;
>
> diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.h b/drivers/gpu/drm/i915/intel_ringbuffer.h
> index 80eb399..e83fbbb 100644
> --- a/drivers/gpu/drm/i915/intel_ringbuffer.h
> +++ b/drivers/gpu/drm/i915/intel_ringbuffer.h
> @@ -386,7 +386,7 @@ int intel_alloc_ringbuffer_obj(struct drm_device *dev,
> void intel_stop_ring_buffer(struct intel_engine_cs *ring);
> void intel_cleanup_ring_buffer(struct intel_engine_cs *ring);
>
> -int __must_check intel_ring_begin(struct intel_engine_cs *ring, int n);
> +int __must_check intel_ring_begin(struct drm_i915_gem_request *req, int n);
> int __must_check intel_ring_cacheline_align(struct drm_i915_gem_request *req);
> int __must_check intel_ring_alloc_request(struct intel_engine_cs *ring,
> struct intel_context *ctx,
>