From ba0001657f95332302bc6494d80ef9fae4e80283 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Tue, 7 May 2019 13:11:05 +0100 Subject: [PATCH] drm/i915: Flush the switch-to-kernel-context harder for DROP_IDLE To complete the idle worker, we must complete 2 passes of wait-for-idle. At the end of the first pass, we queue a switch-to-kernel-context and may only idle after waiting for its completion. Speed up the flush_work by doing the wait explicitly, which then allows us to remove the unbounded loop trying to complete the flush_work in the next patch. References: 79ffac8599c4 ("drm/i915: Invert the GEM wakeref hierarchy") Testcase: igt/gem_ppgtt/flind-and-close-vma-leak Signed-off-by: Chris Wilson Cc: Tvrtko Ursulin Reviewed-by: Tvrtko Ursulin Link: https://patchwork.freedesktop.org/patch/msgid/20190507121108.18377-1-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/i915_debugfs.c | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c index 14cd83e9ea8b..f60aed7747e5 100644 --- a/drivers/gpu/drm/i915/i915_debugfs.c +++ b/drivers/gpu/drm/i915/i915_debugfs.c @@ -3901,14 +3901,26 @@ i915_drop_caches_set(void *data, u64 val) /* No need to check and wait for gpu resets, only libdrm auto-restarts * on ioctls on -EAGAIN. */ - if (val & (DROP_ACTIVE | DROP_RETIRE | DROP_RESET_SEQNO)) { + if (val & (DROP_ACTIVE | DROP_IDLE | DROP_RETIRE | DROP_RESET_SEQNO)) { int ret; ret = mutex_lock_interruptible(&i915->drm.struct_mutex); if (ret) return ret; - if (val & DROP_ACTIVE) + /* + * To finish the flush of the idle_worker, we must complete + * the switch-to-kernel-context, which requires a double + * pass through wait_for_idle: first queues the switch, + * second waits for the switch. + */ + if (ret == 0 && val & (DROP_IDLE | DROP_ACTIVE)) + ret = i915_gem_wait_for_idle(i915, + I915_WAIT_INTERRUPTIBLE | + I915_WAIT_LOCKED, + MAX_SCHEDULE_TIMEOUT); + + if (ret == 0 && val & DROP_IDLE) ret = i915_gem_wait_for_idle(i915, I915_WAIT_INTERRUPTIBLE | I915_WAIT_LOCKED, -- 2.45.2