From a2f60ab34906ce29882cab71b1fcf81308a11009 Mon Sep 17 00:00:00 2001 From: Eric Anholt Date: Thu, 21 Jul 2016 13:39:11 -0700 Subject: [PATCH] drm/vc4: Fix overflow mem unreferencing when the binner runs dry. Overflow memory handling is tricky: While it's still referenced by the BPO registers, we want to keep it from being freed. When we are putting a new set of overflow memory in the registers, we need to assign the old one to the last rendering job using it. We were looking at "what's currently running in the binner", but since the bin/render submission split, we may end up with the binner completing and having no new job while the renderer is still processing. So, if we don't find a bin job at all, look at the highest-seqno (last) render job to attach our overflow to. Signed-off-by: Eric Anholt Fixes: ca26d28bbaa3 ("drm/vc4: improve throughput by pipelining binning and rendering jobs") Cc: stable@vger.kernel.org --- drivers/gpu/drm/vc4/vc4_drv.h | 9 +++++++++ drivers/gpu/drm/vc4/vc4_irq.c | 4 +++- 2 files changed, 12 insertions(+), 1 deletion(-) --- a/drivers/gpu/drm/vc4/vc4_drv.h +++ b/drivers/gpu/drm/vc4/vc4_drv.h @@ -329,6 +329,15 @@ vc4_first_render_job(struct vc4_dev *vc4 struct vc4_exec_info, head); } +static inline struct vc4_exec_info * +vc4_last_render_job(struct vc4_dev *vc4) +{ + if (list_empty(&vc4->render_job_list)) + return NULL; + return list_last_entry(&vc4->render_job_list, + struct vc4_exec_info, head); +} + /** * struct vc4_texture_sample_info - saves the offsets into the UBO for texture * setup parameters. --- a/drivers/gpu/drm/vc4/vc4_irq.c +++ b/drivers/gpu/drm/vc4/vc4_irq.c @@ -83,8 +83,10 @@ vc4_overflow_mem_work(struct work_struct spin_lock_irqsave(&vc4->job_lock, irqflags); current_exec = vc4_first_bin_job(vc4); + if (!current_exec) + current_exec = vc4_last_render_job(vc4); if (current_exec) { - vc4->overflow_mem->seqno = vc4->finished_seqno + 1; + vc4->overflow_mem->seqno = current_exec->seqno; list_add_tail(&vc4->overflow_mem->unref_head, ¤t_exec->unref_list); vc4->overflow_mem = NULL;