[Intel-gfx] [PATCH 03/25] drm/i915/guc: Take engine PM when a context is pinned with GuC submission

Matthew Brost
2021-10-13T20:56:35Z

Taking a PM reference to prevent intel_gt_wait_for_idle from short
circuiting while any user context has scheduling enabled. Returning GT
idle when it is not can cause all sorts of issues throughout the stack.

v2:
(Daniel Vetter)
- Add might_lock annotations to pin / unpin function
v3:
(CI)
- Drop intel_engine_pm_might_put from unpin path as an async put is
used
v4:
(John Harrison)
- Make intel_engine_pm_might_get/put work with GuC virtual engines
- Update commit message
v5:
- Update commit message again

Signed-off-by: Matthew Brost <matthew.brost@intel.com>
---
drivers/gpu/drm/i915/gt/intel_context.c | 2 ++
drivers/gpu/drm/i915/gt/intel_engine_pm.h | 32 +++++++++++++++++
drivers/gpu/drm/i915/gt/intel_gt_pm.h | 10 ++++++
.../gpu/drm/i915/gt/uc/intel_guc_submission.c | 36 +++++++++++++++++--
drivers/gpu/drm/i915/intel_wakeref.h | 12 +++++++
5 files changed, 89 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/i915/gt/intel_context.c b/drivers/gpu/drm/i915/gt/intel_context.c
index d008ef8623ce..f98c9f470ba1 100644
--- a/drivers/gpu/drm/i915/gt/intel_context.c
+++ b/drivers/gpu/drm/i915/gt/intel_context.c
@@ -240,6 +240,8 @@ int __intel_context_do_pin_ww(struct intel_context *ce,
if (err)
goto err_post_unpin;

+ intel_engine_pm_might_get(ce->engine);
+
if (unlikely(intel_context_is_closed(ce))) {
err = -ENOENT;
goto err_unlock;
diff --git a/drivers/gpu/drm/i915/gt/intel_engine_pm.h b/drivers/gpu/drm/i915/gt/intel_engine_pm.h
index 6fdeae668e6e..d68675925b79 100644
--- a/drivers/gpu/drm/i915/gt/intel_engine_pm.h
+++ b/drivers/gpu/drm/i915/gt/intel_engine_pm.h
@@ -6,9 +6,11 @@
#ifndef INTEL_ENGINE_PM_H
#define INTEL_ENGINE_PM_H

+#include "i915_drv.h"
#include "i915_request.h"
#include "intel_engine_types.h"
#include "intel_wakeref.h"
+#include "intel_gt_pm.h"

static inline bool
intel_engine_pm_is_awake(const struct intel_engine_cs *engine)
@@ -31,6 +33,21 @@ static inline bool intel_engine_pm_get_if_awake(struct intel_engine_cs *engine)
return intel_wakeref_get_if_active(&engine->wakeref);
}

+static inline void intel_engine_pm_might_get(struct intel_engine_cs *engine)
+{
+ if (!intel_engine_is_virtual(engine)) {
+ intel_wakeref_might_get(&engine->wakeref);
+ } else {
+ struct intel_gt *gt = engine->gt;
+ struct intel_engine_cs *tengine;
+ intel_engine_mask_t tmp, mask = engine->mask;
+
+ for_each_engine_masked(tengine, gt, mask, tmp)
+ intel_wakeref_might_get(&tengine->wakeref);
+ }
+ intel_gt_pm_might_get(engine->gt);
+}
+
static inline void intel_engine_pm_put(struct intel_engine_cs *engine)
{
intel_wakeref_put(&engine->wakeref);
@@ -52,6 +69,21 @@ static inline void intel_engine_pm_flush(struct intel_engine_cs *engine)
intel_wakeref_unlock_wait(&engine->wakeref);
}

+static inline void intel_engine_pm_might_put(struct intel_engine_cs *engine)
+{
+ if (!intel_engine_is_virtual(engine)) {
+ intel_wakeref_might_put(&engine->wakeref);
+ } else {
+ struct intel_gt *gt = engine->gt;
+ struct intel_engine_cs *tengine;
+ intel_engine_mask_t tmp, mask = engine->mask;
+
+ for_each_engine_masked(tengine, gt, mask, tmp)
+ intel_wakeref_might_put(&tengine->wakeref);
+ }
+ intel_gt_pm_might_put(engine->gt);
+}
+
static inline struct i915_request *
intel_engine_create_kernel_request(struct intel_engine_cs *engine)
{
diff --git a/drivers/gpu/drm/i915/gt/intel_gt_pm.h b/drivers/gpu/drm/i915/gt/intel_gt_pm.h
index 05de6c1af25b..bc898df7a48c 100644
--- a/drivers/gpu/drm/i915/gt/intel_gt_pm.h
+++ b/drivers/gpu/drm/i915/gt/intel_gt_pm.h
@@ -31,6 +31,11 @@ static inline bool intel_gt_pm_get_if_awake(struct intel_gt *gt)
return intel_wakeref_get_if_active(&gt->wakeref);
}

+static inline void intel_gt_pm_might_get(struct intel_gt *gt)
+{
+ intel_wakeref_might_get(&gt->wakeref);
+}
+
static inline void intel_gt_pm_put(struct intel_gt *gt)
{
intel_wakeref_put(&gt->wakeref);
@@ -41,6 +46,11 @@ static inline void intel_gt_pm_put_async(struct intel_gt *gt)
intel_wakeref_put_async(&gt->wakeref);
}

+static inline void intel_gt_pm_might_put(struct intel_gt *gt)
+{
+ intel_wakeref_might_put(&gt->wakeref);
+}
+
#define with_intel_gt_pm(gt, tmp) \
for (tmp = 1, intel_gt_pm_get(gt); tmp; \
intel_gt_pm_put(gt), tmp = 0)
diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
index d2ce47b5541e..51d3963cebbf 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
+++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
@@ -1571,7 +1571,12 @@ static int guc_context_pre_pin(struct intel_context *ce,

static int guc_context_pin(struct intel_context *ce, void *vaddr)
{
- return __guc_context_pin(ce, ce->engine, vaddr);
+ int ret = __guc_context_pin(ce, ce->engine, vaddr);
+
+ if (likely(!ret && !intel_context_is_barrier(ce)))
+ intel_engine_pm_get(ce->engine);
+
+ return ret;
}

static void guc_context_unpin(struct intel_context *ce)
@@ -1580,6 +1585,9 @@ static void guc_context_unpin(struct intel_context *ce)

unpin_guc_id(guc, ce);
lrc_unpin(ce);
+
+ if (likely(!intel_context_is_barrier(ce)))
+ intel_engine_pm_put_async(ce->engine);
}

static void guc_context_post_unpin(struct intel_context *ce)
@@ -2341,8 +2349,30 @@ static int guc_virtual_context_pre_pin(struct intel_context *ce,
static int guc_virtual_context_pin(struct intel_context *ce, void *vaddr)
{
struct intel_engine_cs *engine = guc_virtual_get_sibling(ce->engine, 0);
+ int ret = __guc_context_pin(ce, engine, vaddr);
+ intel_engine_mask_t tmp, mask = ce->engine->mask;
+
+ if (likely(!ret))
+ for_each_engine_masked(engine, ce->engine->gt, mask, tmp)
+ intel_engine_pm_get(engine);

- return __guc_context_pin(ce, engine, vaddr);
+ return ret;
+}
+
+static void guc_virtual_context_unpin(struct intel_context *ce)
+{
+ intel_engine_mask_t tmp, mask = ce->engine->mask;
+ struct intel_engine_cs *engine;
+ struct intel_guc *guc = ce_to_guc(ce);
+
+ GEM_BUG_ON(context_enabled(ce));
+ GEM_BUG_ON(intel_context_is_barrier(ce));
+
+ unpin_guc_id(guc, ce);
+ lrc_unpin(ce);
+
+ for_each_engine_masked(engine, ce->engine->gt, mask, tmp)
+ intel_engine_pm_put_async(engine);
}

static void guc_virtual_context_enter(struct intel_context *ce)
@@ -2379,7 +2409,7 @@ static const struct intel_context_ops virtual_guc_context_ops = {

.pre_pin = guc_virtual_context_pre_pin,
.pin = guc_virtual_context_pin,
- .unpin = guc_context_unpin,
+ .unpin = guc_virtual_context_unpin,
.post_unpin = guc_context_post_unpin,

.ban = guc_context_ban,
diff --git a/drivers/gpu/drm/i915/intel_wakeref.h b/drivers/gpu/drm/i915/intel_wakeref.h
index 545c8f277c46..4f4c2e15e736 100644
--- a/drivers/gpu/drm/i915/intel_wakeref.h
+++ b/drivers/gpu/drm/i915/intel_wakeref.h
@@ -123,6 +123,12 @@ enum {
__INTEL_WAKEREF_PUT_LAST_BIT__
};

+static inline void
+intel_wakeref_might_get(struct intel_wakeref *wf)
+{
+ might_lock(&wf->mutex);
+}
+
/**
* intel_wakeref_put_flags: Release the wakeref
* @wf: the wakeref
@@ -170,6 +176,12 @@ intel_wakeref_put_delay(struct intel_wakeref *wf, unsigned long delay)
FIELD_PREP(INTEL_WAKEREF_PUT_DELAY, delay));
}

+static inline void
+intel_wakeref_might_put(struct intel_wakeref *wf)
+{
+ might_lock(&wf->mutex);
+}
+
/**
* intel_wakeref_lock: Lock the wakeref (mutex)
* @wf: the wakeref
--
2.32.0