[Intel-gfx] [PATCH 42/51] drm/i915/guc: Implement banned contexts for GuC submission

Matthew Brost
2021-07-16T20:00:51Z

When using GuC submission, if a context gets banned disable scheduling
and mark all inflight requests as complete.

Cc: John Harrison <John.C.Harrison@Intel.com>
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
---
drivers/gpu/drm/i915/gem/i915_gem_context.c | 2 +-
drivers/gpu/drm/i915/gt/intel_context.h | 13 ++
drivers/gpu/drm/i915/gt/intel_context_types.h | 2 +
drivers/gpu/drm/i915/gt/intel_reset.c | 32 +---
.../gpu/drm/i915/gt/intel_ring_submission.c | 20 +++
drivers/gpu/drm/i915/gt/uc/intel_guc.h | 2 +
.../gpu/drm/i915/gt/uc/intel_guc_submission.c | 151 ++++++++++++++++--
drivers/gpu/drm/i915/i915_trace.h | 10 ++
8 files changed, 195 insertions(+), 37 deletions(-)

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_context.c b/drivers/gpu/drm/i915/gem/i915_gem_context.c
index 28c62f7ccfc7..d87a4c6da5bc 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_context.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_context.c
@@ -1084,7 +1084,7 @@ static void kill_engines(struct i915_gem_engines *engines, bool ban)
for_each_gem_engine(ce, engines, it) {
struct intel_engine_cs *engine;

- if (ban && intel_context_set_banned(ce))
+ if (ban && intel_context_ban(ce, NULL))
continue;

/*
diff --git a/drivers/gpu/drm/i915/gt/intel_context.h b/drivers/gpu/drm/i915/gt/intel_context.h
index 2ed9bf5f91a5..814d9277096a 100644
--- a/drivers/gpu/drm/i915/gt/intel_context.h
+++ b/drivers/gpu/drm/i915/gt/intel_context.h
@@ -16,6 +16,7 @@
#include "intel_engine_types.h"
#include "intel_ring_types.h"
#include "intel_timeline_types.h"
+#include "i915_trace.h"

#define CE_TRACE(ce, fmt, ...) do { \
const struct intel_context *ce__ = (ce); \
@@ -243,6 +244,18 @@ static inline bool intel_context_set_banned(struct intel_context *ce)
return test_and_set_bit(CONTEXT_BANNED, &ce->flags);
}

+static inline bool intel_context_ban(struct intel_context *ce,
+ struct i915_request *rq)
+{
+ bool ret = intel_context_set_banned(ce);
+
+ trace_intel_context_ban(ce);
+ if (ce->ops->ban)
+ ce->ops->ban(ce, rq);
+
+ return ret;
+}
+
static inline bool
intel_context_force_single_submission(const struct intel_context *ce)
{
diff --git a/drivers/gpu/drm/i915/gt/intel_context_types.h b/drivers/gpu/drm/i915/gt/intel_context_types.h
index 035108c10b2c..57c19ee3e313 100644
--- a/drivers/gpu/drm/i915/gt/intel_context_types.h
+++ b/drivers/gpu/drm/i915/gt/intel_context_types.h
@@ -35,6 +35,8 @@ struct intel_context_ops {

int (*alloc)(struct intel_context *ce);

+ void (*ban)(struct intel_context *ce, struct i915_request *rq);
+
int (*pre_pin)(struct intel_context *ce, struct i915_gem_ww_ctx *ww, void **vaddr);
int (*pin)(struct intel_context *ce, void *vaddr);
void (*unpin)(struct intel_context *ce);
diff --git a/drivers/gpu/drm/i915/gt/intel_reset.c b/drivers/gpu/drm/i915/gt/intel_reset.c
index f3cdbf4ba5c8..3ed694cab5af 100644
--- a/drivers/gpu/drm/i915/gt/intel_reset.c
+++ b/drivers/gpu/drm/i915/gt/intel_reset.c
@@ -22,7 +22,6 @@
#include "intel_reset.h"

#include "uc/intel_guc.h"
-#include "uc/intel_guc_submission.h"

#define RESET_MAX_RETRIES 3

@@ -39,21 +38,6 @@ static void rmw_clear_fw(struct intel_uncore *uncore, i915_reg_t reg, u32 clr)
intel_uncore_rmw_fw(uncore, reg, clr, 0);
}

-static void skip_context(struct i915_request *rq)
-{
- struct intel_context *hung_ctx = rq->context;
-
- list_for_each_entry_from_rcu(rq, &hung_ctx->timeline->requests, link) {
- if (!i915_request_is_active(rq))
- return;
-
- if (rq->context == hung_ctx) {
- i915_request_set_error_once(rq, -EIO);
- __i915_request_skip(rq);
- }
- }
-}
-
static void client_mark_guilty(struct i915_gem_context *ctx, bool banned)
{
struct drm_i915_file_private *file_priv = ctx->file_priv;
@@ -88,10 +72,8 @@ static bool mark_guilty(struct i915_request *rq)
bool banned;
int i;

- if (intel_context_is_closed(rq->context)) {
- intel_context_set_banned(rq->context);
+ if (intel_context_is_closed(rq->context))
return true;
- }

rcu_read_lock();
ctx = rcu_dereference(rq->context->gem_context);
@@ -123,11 +105,9 @@ static bool mark_guilty(struct i915_request *rq)
banned = !i915_gem_context_is_recoverable(ctx);
if (time_before(jiffies, prev_hang + CONTEXT_FAST_HANG_JIFFIES))
banned = true;
- if (banned) {
+ if (banned)
drm_dbg(&ctx->i915->drm, "context %s: guilty %d, banned\n",
ctx->name, atomic_read(&ctx->guilty_count));
- intel_context_set_banned(rq->context);
- }

client_mark_guilty(ctx, banned);

@@ -149,6 +129,8 @@ static void mark_innocent(struct i915_request *rq)

void __i915_request_reset(struct i915_request *rq, bool guilty)
{
+ bool banned = false;
+
RQ_TRACE(rq, "guilty? %s\n", yesno(guilty));
GEM_BUG_ON(__i915_request_is_complete(rq));

@@ -156,13 +138,15 @@ void __i915_request_reset(struct i915_request *rq, bool guilty)
if (guilty) {
i915_request_set_error_once(rq, -EIO);
__i915_request_skip(rq);
- if (mark_guilty(rq) && !intel_engine_uses_guc(rq->engine))
- skip_context(rq);
+ banned = mark_guilty(rq);
} else {
i915_request_set_error_once(rq, -EAGAIN);
mark_innocent(rq);
}
rcu_read_unlock();
+
+ if (banned)
+ intel_context_ban(rq->context, rq);
}

static bool i915_in_reset(struct pci_dev *pdev)
diff --git a/drivers/gpu/drm/i915/gt/intel_ring_submission.c b/drivers/gpu/drm/i915/gt/intel_ring_submission.c
index 3b1471c50d40..03939be4297e 100644
--- a/drivers/gpu/drm/i915/gt/intel_ring_submission.c
+++ b/drivers/gpu/drm/i915/gt/intel_ring_submission.c
@@ -586,9 +586,29 @@ static void ring_context_reset(struct intel_context *ce)
clear_bit(CONTEXT_VALID_BIT, &ce->flags);
}

+static void ring_context_ban(struct intel_context *ce,
+ struct i915_request *rq)
+{
+ struct intel_engine_cs *engine;
+
+ if (!rq || !i915_request_is_active(rq))
+ return;
+
+ engine = rq->engine;
+ lockdep_assert_held(&engine->sched_engine->lock);
+ list_for_each_entry_continue(rq, &engine->sched_engine->requests,
+ sched.link)
+ if (rq->context == ce) {
+ i915_request_set_error_once(rq, -EIO);
+ __i915_request_skip(rq);
+ }
+}
+
static const struct intel_context_ops ring_context_ops = {
.alloc = ring_context_alloc,

+ .ban = ring_context_ban,
+
.pre_pin = ring_context_pre_pin,
.pin = ring_context_pin,
.unpin = ring_context_unpin,
diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc.h b/drivers/gpu/drm/i915/gt/uc/intel_guc.h
index dc18ac510ac8..eb6062f95d3b 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_guc.h
+++ b/drivers/gpu/drm/i915/gt/uc/intel_guc.h
@@ -274,6 +274,8 @@ void intel_guc_find_hung_context(struct intel_engine_cs *engine);

int intel_guc_global_policies_update(struct intel_guc *guc);

+void intel_guc_context_ban(struct intel_context *ce, struct i915_request *rq);
+
void intel_guc_submission_reset_prepare(struct intel_guc *guc);
void intel_guc_submission_reset(struct intel_guc *guc, bool stalled);
void intel_guc_submission_reset_finish(struct intel_guc *guc);
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 6536bd6807a0..149990196e3a 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
+++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
@@ -125,6 +125,7 @@ static inline void clr_context_pending_enable(struct intel_context *ce)
#define SCHED_STATE_WAIT_FOR_DEREGISTER_TO_REGISTER BIT(0)
#define SCHED_STATE_DESTROYED BIT(1)
#define SCHED_STATE_PENDING_DISABLE BIT(2)
+#define SCHED_STATE_BANNED BIT(3)
static inline void init_sched_state(struct intel_context *ce)
{
/* Only should be called from guc_lrc_desc_pin() */
@@ -187,6 +188,23 @@ static inline void clr_context_pending_disable(struct intel_context *ce)
(ce->guc_state.sched_state & ~SCHED_STATE_PENDING_DISABLE);
}

+static inline bool context_banned(struct intel_context *ce)
+{
+ return (ce->guc_state.sched_state & SCHED_STATE_BANNED);
+}
+
+static inline void set_context_banned(struct intel_context *ce)
+{
+ lockdep_assert_held(&ce->guc_state.lock);
+ ce->guc_state.sched_state |= SCHED_STATE_BANNED;
+}
+
+static inline void clr_context_banned(struct intel_context *ce)
+{
+ lockdep_assert_held(&ce->guc_state.lock);
+ ce->guc_state.sched_state &= ~SCHED_STATE_BANNED;
+}
+
static inline bool context_guc_id_invalid(struct intel_context *ce)
{
return (ce->guc_id == GUC_INVALID_LRC_ID);
@@ -356,13 +374,23 @@ static int guc_lrc_desc_pin(struct intel_context *ce, bool loop);

static int guc_add_request(struct intel_guc *guc, struct i915_request *rq)
{
- int err;
+ int err = 0;
struct intel_context *ce = rq->context;
u32 action[3];
int len = 0;
u32 g2h_len_dw = 0;
bool enabled;

+ /*
+ * Corner case where requests were sitting in the priority list or a
+ * request resubmitted after the context was banned.
+ */
+ if (unlikely(intel_context_is_banned(ce))) {
+ i915_request_put(i915_request_mark_eio(rq));
+ intel_engine_signal_breadcrumbs(ce->engine);
+ goto out;
+ }
+
GEM_BUG_ON(!atomic_read(&ce->guc_id_ref));
GEM_BUG_ON(context_guc_id_invalid(ce));

@@ -398,6 +426,8 @@ static int guc_add_request(struct intel_guc *guc, struct i915_request *rq)
clr_context_pending_enable(ce);
intel_context_put(ce);
}
+ if (likely(!err))
+ trace_i915_request_guc_submit(rq);

out:
return err;
@@ -462,7 +492,6 @@ static int guc_dequeue_one_context(struct intel_guc *guc)
guc->stalled_request = last;
return false;
}
- trace_i915_request_guc_submit(last);
}

guc->stalled_request = NULL;
@@ -501,12 +530,13 @@ static void cs_irq_handler(struct intel_engine_cs *engine, u16 iir)
static void __guc_context_destroy(struct intel_context *ce);
static void release_guc_id(struct intel_guc *guc, struct intel_context *ce);
static void guc_signal_context_fence(struct intel_context *ce);
+static void guc_cancel_context_requests(struct intel_context *ce);

static void scrub_guc_desc_for_outstanding_g2h(struct intel_guc *guc)
{
struct intel_context *ce;
unsigned long index, flags;
- bool pending_disable, pending_enable, deregister, destroyed;
+ bool pending_disable, pending_enable, deregister, destroyed, banned;

xa_for_each(&guc->context_lookup, index, ce) {
/* Flush context */
@@ -524,6 +554,7 @@ static void scrub_guc_desc_for_outstanding_g2h(struct intel_guc *guc)
pending_enable = context_pending_enable(ce);
pending_disable = context_pending_disable(ce);
deregister = context_wait_for_deregister_to_register(ce);
+ banned = context_banned(ce);
init_sched_state(ce);

if (pending_enable || destroyed || deregister) {
@@ -541,6 +572,10 @@ static void scrub_guc_desc_for_outstanding_g2h(struct intel_guc *guc)
/* Not mutualy exclusive with above if statement. */
if (pending_disable) {
guc_signal_context_fence(ce);
+ if (banned) {
+ guc_cancel_context_requests(ce);
+ intel_engine_signal_breadcrumbs(ce->engine);
+ }
intel_context_sched_disable_unpin(ce);
atomic_dec(&guc->outstanding_submission_g2h);
intel_context_put(ce);
@@ -659,6 +694,9 @@ static void guc_reset_state(struct intel_context *ce, u32 head, bool scrub)
{
struct intel_engine_cs *engine = __context_to_physical_engine(ce);

+ if (intel_context_is_banned(ce))
+ return;
+
GEM_BUG_ON(!intel_context_is_pinned(ce));

/*
@@ -729,6 +767,8 @@ static void __guc_reset_context(struct intel_context *ce, bool stalled)
struct i915_request *rq;
u32 head;

+ intel_context_get(ce);
+
/*
* GuC will implicitly mark the context as non-schedulable
* when it sends the reset notification. Make sure our state
@@ -754,6 +794,7 @@ static void __guc_reset_context(struct intel_context *ce, bool stalled)
out_replay:
guc_reset_state(ce, head, stalled);
__unwind_incomplete_requests(ce);
+ intel_context_put(ce);
}

void intel_guc_submission_reset(struct intel_guc *guc, bool stalled)
@@ -936,8 +977,6 @@ static int guc_bypass_tasklet_submit(struct intel_guc *guc,
ret = guc_add_request(guc, rq);
if (ret == -EBUSY)
guc->stalled_request = rq;
- else
- trace_i915_request_guc_submit(rq);

if (unlikely(ret == -EPIPE))
disable_submission(guc);
@@ -1329,13 +1368,77 @@ static u16 prep_context_pending_disable(struct intel_context *ce)
return ce->guc_id;
}

+static void __guc_context_set_preemption_timeout(struct intel_guc *guc,
+ u16 guc_id,
+ u32 preemption_timeout)
+{
+ u32 action [] = {
+ INTEL_GUC_ACTION_SET_CONTEXT_PREEMPTION_TIMEOUT,
+ guc_id,
+ preemption_timeout
+ };
+
+ intel_guc_send_busy_loop(guc, action, ARRAY_SIZE(action), 0, true);
+}
+
+static void guc_context_ban(struct intel_context *ce, struct i915_request *rq)
+{
+ struct intel_guc *guc = ce_to_guc(ce);
+ struct intel_runtime_pm *runtime_pm =
+ &ce->engine->gt->i915->runtime_pm;
+ intel_wakeref_t wakeref;
+ unsigned long flags;
+
+ guc_flush_submissions(guc);
+
+ spin_lock_irqsave(&ce->guc_state.lock, flags);
+ set_context_banned(ce);
+
+ if (submission_disabled(guc) || (!context_enabled(ce) &&
+ !context_pending_disable(ce))) {
+ spin_unlock_irqrestore(&ce->guc_state.lock, flags);
+
+ guc_cancel_context_requests(ce);
+ intel_engine_signal_breadcrumbs(ce->engine);
+ } else if (!context_pending_disable(ce)) {
+ u16 guc_id;
+
+ /*
+ * We add +2 here as the schedule disable complete CTB handler
+ * calls intel_context_sched_disable_unpin (-2 to pin_count).
+ */
+ atomic_add(2, &ce->pin_count);
+
+ guc_id = prep_context_pending_disable(ce);
+ spin_unlock_irqrestore(&ce->guc_state.lock, flags);
+
+ /*
+ * In addition to disabling scheduling, set the preemption
+ * timeout to the minimum value (1 us) so the banned context
+ * gets kicked off the HW ASAP.
+ */
+ with_intel_runtime_pm(runtime_pm, wakeref) {
+ __guc_context_set_preemption_timeout(guc, guc_id, 1);
+ __guc_context_sched_disable(guc, ce, guc_id);
+ }
+ } else {
+ if (!context_guc_id_invalid(ce))
+ with_intel_runtime_pm(runtime_pm, wakeref)
+ __guc_context_set_preemption_timeout(guc,
+ ce->guc_id,
+ 1);
+ spin_unlock_irqrestore(&ce->guc_state.lock, flags);
+ }
+}
+
static void guc_context_sched_disable(struct intel_context *ce)
{
struct intel_guc *guc = ce_to_guc(ce);
- struct intel_runtime_pm *runtime_pm = &ce->engine->gt->i915->runtime_pm;
unsigned long flags;
- u16 guc_id;
+ struct intel_runtime_pm *runtime_pm = &ce->engine->gt->i915->runtime_pm;
intel_wakeref_t wakeref;
+ u16 guc_id;
+ bool enabled;

if (submission_disabled(guc) || context_guc_id_invalid(ce) ||
!lrc_desc_registered(guc, ce->guc_id)) {
@@ -1349,14 +1452,22 @@ static void guc_context_sched_disable(struct intel_context *ce)
spin_lock_irqsave(&ce->guc_state.lock, flags);

/*
- * We have to check if the context has been pinned again as another pin
- * operation is allowed to pass this function. Checking the pin count,
- * within ce->guc_state.lock, synchronizes this function with
+ * We have to check if the context has been disabled by another thread.
+ * We also have to check if the context has been pinned again as another
+ * pin operation is allowed to pass this function. Checking the pin
+ * count, within ce->guc_state.lock, synchronizes this function with
* guc_request_alloc ensuring a request doesn't slip through the
* 'context_pending_disable' fence. Checking within the spin lock (can't
* sleep) ensures another process doesn't pin this context and generate
* a request before we set the 'context_pending_disable' flag here.
*/
+ enabled = context_enabled(ce);
+ if (unlikely(!enabled || submission_disabled(guc))) {
+ if (enabled)
+ clr_context_enabled(ce);
+ spin_unlock_irqrestore(&ce->guc_state.lock, flags);
+ goto unpin;
+ }
if (unlikely(atomic_add_unless(&ce->pin_count, -2, 2))) {
spin_unlock_irqrestore(&ce->guc_state.lock, flags);
return;
@@ -1513,6 +1624,8 @@ static const struct intel_context_ops guc_context_ops = {
.unpin = guc_context_unpin,
.post_unpin = guc_context_post_unpin,

+ .ban = guc_context_ban,
+
.enter = intel_context_enter_engine,
.exit = intel_context_exit_engine,

@@ -1706,6 +1819,8 @@ static const struct intel_context_ops virtual_guc_context_ops = {
.unpin = guc_context_unpin,
.post_unpin = guc_context_post_unpin,

+ .ban = guc_context_ban,
+
.enter = guc_virtual_context_enter,
.exit = guc_virtual_context_exit,

@@ -2159,6 +2274,8 @@ int intel_guc_sched_done_process_msg(struct intel_guc *guc,
if (context_pending_enable(ce)) {
clr_context_pending_enable(ce);
} else if (context_pending_disable(ce)) {
+ bool banned;
+
/*
* Unpin must be done before __guc_signal_context_fence,
* otherwise a race exists between the requests getting
@@ -2169,9 +2286,16 @@ int intel_guc_sched_done_process_msg(struct intel_guc *guc,
intel_context_sched_disable_unpin(ce);

spin_lock_irqsave(&ce->guc_state.lock, flags);
+ banned = context_banned(ce);
+ clr_context_banned(ce);
clr_context_pending_disable(ce);
__guc_signal_context_fence(ce);
spin_unlock_irqrestore(&ce->guc_state.lock, flags);
+
+ if (banned) {
+ guc_cancel_context_requests(ce);
+ intel_engine_signal_breadcrumbs(ce->engine);
+ }
}

decr_outstanding_submission_g2h(guc);
@@ -2206,8 +2330,11 @@ static void guc_handle_context_reset(struct intel_guc *guc,
struct intel_context *ce)
{
trace_intel_context_reset(ce);
- capture_error_state(guc, ce);
- guc_context_replay(ce);
+
+ if (likely(!intel_context_is_banned(ce))) {
+ capture_error_state(guc, ce);
+ guc_context_replay(ce);
+ }
}

int intel_guc_context_reset_process_msg(struct intel_guc *guc,
diff --git a/drivers/gpu/drm/i915/i915_trace.h b/drivers/gpu/drm/i915/i915_trace.h
index c095c4d39456..937d3706af9b 100644
--- a/drivers/gpu/drm/i915/i915_trace.h
+++ b/drivers/gpu/drm/i915/i915_trace.h
@@ -934,6 +934,11 @@ DEFINE_EVENT(intel_context, intel_context_reset,
TP_ARGS(ce)
);

+DEFINE_EVENT(intel_context, intel_context_ban,
+ TP_PROTO(struct intel_context *ce),
+ TP_ARGS(ce)
+);
+
DEFINE_EVENT(intel_context, intel_context_register,
TP_PROTO(struct intel_context *ce),
TP_ARGS(ce)
@@ -1036,6 +1041,11 @@ trace_intel_context_reset(struct intel_context *ce)
{
}

+static inline void
+trace_intel_context_ban(struct intel_context *ce)
+{
+}
+
static inline void
trace_intel_context_register(struct intel_context *ce)
{
--
2.28.0