From 1bfc2e144d735d327c8d0a95f27eaa75be8904ce Mon Sep 17 00:00:00 2001
From: Chris Wilson <chris@chris-wilson.co.uk>
Date: Mon, 23 Dec 2019 21:10:08 +0000
Subject: drm/i915/gt: Flush other retirees inside intel_gt_retire_requests()
Git-commit: 30084b143de7a320ab8fc609a8ad3a396232d002
Patch-mainline: v5.6-rc1
References: jsc#SLE-12680, jsc#SLE-12880, jsc#SLE-12882, jsc#SLE-12883, jsc#SLE-13496, jsc#SLE-15322
Our goal in wait_for_idle (intel_gt_retire_requests) is to the current
workload *and* their idle barriers. This requires us to notice the late
arrival of those, which is done by inspecting the list of active
timelines. However, if a concurrent retirer is running that new timeline
may not be added until after we drop the lock -- so flush concurrent
retirers before we take the lock and inspect the list.
Closes: https://gitlab.freedesktop.org/drm/intel/issues/878
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Andi Shyti <andi.shyti@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191223211008.2371613-1-chris@chris-wilson.co.uk
Signed-off-by: Patrik Jakobsson <pjakobsson@suse.de>
---
drivers/gpu/drm/i915/gt/intel_engine.h | 2 +-
drivers/gpu/drm/i915/gt/intel_engine_cs.c | 6 +-----
drivers/gpu/drm/i915/gt/intel_gt_requests.c | 16 +++++-----------
3 files changed, 7 insertions(+), 17 deletions(-)
diff --git a/drivers/gpu/drm/i915/gt/intel_engine.h b/drivers/gpu/drm/i915/gt/intel_engine.h
index 79ecac5ac0ab..71f1bcdfc92f 100644
--- a/drivers/gpu/drm/i915/gt/intel_engine.h
+++ b/drivers/gpu/drm/i915/gt/intel_engine.h
@@ -282,7 +282,7 @@ static inline void __intel_engine_reset(struct intel_engine_cs *engine,
bool intel_engines_are_idle(struct intel_gt *gt);
bool intel_engine_is_idle(struct intel_engine_cs *engine);
-bool intel_engine_flush_submission(struct intel_engine_cs *engine);
+void intel_engine_flush_submission(struct intel_engine_cs *engine);
void intel_engines_reset_default_submission(struct intel_gt *gt);
diff --git a/drivers/gpu/drm/i915/gt/intel_engine_cs.c b/drivers/gpu/drm/i915/gt/intel_engine_cs.c
index ddf9543b1261..825c94e7ca0b 100644
--- a/drivers/gpu/drm/i915/gt/intel_engine_cs.c
+++ b/drivers/gpu/drm/i915/gt/intel_engine_cs.c
@@ -1047,10 +1047,9 @@ static bool ring_is_idle(struct intel_engine_cs *engine)
return idle;
}
-bool intel_engine_flush_submission(struct intel_engine_cs *engine)
+void intel_engine_flush_submission(struct intel_engine_cs *engine)
{
struct tasklet_struct *t = &engine->execlists.tasklet;
- bool active = tasklet_is_locked(t);
if (__tasklet_is_scheduled(t)) {
local_bh_disable();
@@ -1061,13 +1060,10 @@ bool intel_engine_flush_submission(struct intel_engine_cs *engine)
tasklet_unlock(t);
}
local_bh_enable();
- active = true;
}
/* Otherwise flush the tasklet if it was running on another cpu */
tasklet_unlock_wait(t);
-
- return active;
}
/**
diff --git a/drivers/gpu/drm/i915/gt/intel_gt_requests.c b/drivers/gpu/drm/i915/gt/intel_gt_requests.c
index 9e75fa1b6bc1..fc691c130ba6 100644
--- a/drivers/gpu/drm/i915/gt/intel_gt_requests.c
+++ b/drivers/gpu/drm/i915/gt/intel_gt_requests.c
@@ -26,21 +26,18 @@ static bool retire_requests(struct intel_timeline *tl)
return !i915_active_fence_isset(&tl->last_request);
}
-static bool flush_submission(struct intel_gt *gt)
+static void flush_submission(struct intel_gt *gt)
{
struct intel_engine_cs *engine;
enum intel_engine_id id;
- bool active = false;
if (!intel_gt_pm_is_awake(gt))
- return false;
+ return;
for_each_engine(engine, gt, id) {
- active |= intel_engine_flush_submission(engine);
- active |= flush_work(&engine->retire_work);
+ intel_engine_flush_submission(engine);
+ flush_work(&engine->retire_work);
}
-
- return active;
}
static void engine_retire(struct work_struct *work)
@@ -126,7 +123,6 @@ long intel_gt_retire_requests_timeout(struct intel_gt *gt, long timeout)
timeout = -timeout, interruptible = false;
flush_submission(gt); /* kick the ksoftirqd tasklets */
-
spin_lock(&timelines->lock);
list_for_each_entry_safe(tl, tn, &timelines->active_list, link) {
if (!mutex_trylock(&tl->mutex)) {
@@ -153,6 +149,7 @@ long intel_gt_retire_requests_timeout(struct intel_gt *gt, long timeout)
active_count += !retire_requests(tl);
+ flush_submission(gt); /* sync with concurrent retirees */
spin_lock(&timelines->lock);
/* Resume iteration after dropping lock */
@@ -173,9 +170,6 @@ long intel_gt_retire_requests_timeout(struct intel_gt *gt, long timeout)
list_for_each_entry_safe(tl, tn, &free, link)
__intel_timeline_free(&tl->kref);
- if (flush_submission(gt))
- active_count++;
-
return active_count ? timeout : 0;
}
--
2.28.0