@@ -1295,7 +1295,7 @@ static int i915_hangcheck_info(struct seq_file *m, void *unused)
with_intel_runtime_pm(dev_priv, wakeref) {
for_each_engine(engine, dev_priv, id) {
acthd[id] = intel_engine_get_active_head(engine);
- seqno[id] = intel_engine_get_seqno(engine);
+ seqno[id] = intel_engine_get_hangcheck_seqno(engine);
}
intel_engine_get_instdone(dev_priv->engine[RCS], &instdone);
@@ -1315,8 +1315,9 @@ static int i915_hangcheck_info(struct seq_file *m, void *unused)
for_each_engine(engine, dev_priv, id) {
seq_printf(m, "%s:\n", engine->name);
seq_printf(m, "\tseqno = %x [current %x, last %x], %dms ago\n",
- engine->hangcheck.seqno, seqno[id],
- intel_engine_last_submit(engine),
+ engine->hangcheck.last_seqno,
+ seqno[id],
+ engine->hangcheck.next_seqno,
jiffies_to_msecs(jiffies -
engine->hangcheck.action_timestamp));
@@ -1497,10 +1497,11 @@ void intel_engine_dump(struct intel_engine_cs *engine,
if (i915_reset_failed(engine->i915))
drm_printf(m, "*** WEDGED ***\n");
- drm_printf(m, "\tcurrent seqno %x, last %x, hangcheck %x [%d ms]\n",
+ drm_printf(m, "\tcurrent seqno %x, last %x, hangcheck %x/%x [%d ms]\n",
intel_engine_get_seqno(engine),
intel_engine_last_submit(engine),
- engine->hangcheck.seqno,
+ engine->hangcheck.last_seqno,
+ engine->hangcheck.next_seqno,
jiffies_to_msecs(jiffies - engine->hangcheck.action_timestamp));
drm_printf(m, "\tReset count: %d (global %d)\n",
i915_reset_engine_count(error, engine),
@@ -133,21 +133,21 @@ static void hangcheck_load_sample(struct intel_engine_cs *engine,
struct hangcheck *hc)
{
hc->acthd = intel_engine_get_active_head(engine);
- hc->seqno = intel_engine_get_seqno(engine);
+ hc->seqno = intel_engine_get_hangcheck_seqno(engine);
}
static void hangcheck_store_sample(struct intel_engine_cs *engine,
const struct hangcheck *hc)
{
engine->hangcheck.acthd = hc->acthd;
- engine->hangcheck.seqno = hc->seqno;
+ engine->hangcheck.last_seqno = hc->seqno;
}
static enum intel_engine_hangcheck_action
hangcheck_get_action(struct intel_engine_cs *engine,
const struct hangcheck *hc)
{
- if (engine->hangcheck.seqno != hc->seqno)
+ if (engine->hangcheck.last_seqno != hc->seqno)
return ENGINE_ACTIVE_SEQNO;
if (intel_engine_is_idle(engine))
@@ -178,6 +178,12 @@ static inline u32 intel_hws_seqno_address(struct intel_engine_cs *engine)
I915_GEM_HWS_INDEX_ADDR);
}
+static inline u32 intel_hws_hangcheck_address(struct intel_engine_cs *engine)
+{
+ return (i915_ggtt_offset(engine->status_page.vma) +
+ I915_GEM_HWS_HANGCHECK_ADDR);
+}
+
static inline struct i915_priolist *to_priolist(struct rb_node *rb)
{
return rb_entry(rb, struct i915_priolist, node);
@@ -2206,6 +2212,10 @@ static u32 *gen8_emit_fini_breadcrumb(struct i915_request *request, u32 *cs)
request->fence.seqno,
request->timeline->hwsp_offset);
+ cs = gen8_emit_ggtt_write(cs,
+ intel_engine_next_hangcheck_seqno(request->engine),
+ intel_hws_hangcheck_address(request->engine));
+
cs = gen8_emit_ggtt_write(cs,
request->global_seqno,
intel_hws_seqno_address(request->engine));
@@ -2230,6 +2240,11 @@ static u32 *gen8_emit_fini_breadcrumb_rcs(struct i915_request *request, u32 *cs)
PIPE_CONTROL_FLUSH_ENABLE |
PIPE_CONTROL_CS_STALL);
+ cs = gen8_emit_ggtt_write_rcs(cs,
+ intel_engine_next_hangcheck_seqno(request->engine),
+ intel_hws_hangcheck_address(request->engine),
+ PIPE_CONTROL_CS_STALL);
+
cs = gen8_emit_ggtt_write_rcs(cs,
request->global_seqno,
intel_hws_seqno_address(request->engine),
@@ -43,6 +43,12 @@
*/
#define LEGACY_REQUEST_SIZE 200
+static inline u32 hws_hangcheck_address(struct intel_engine_cs *engine)
+{
+ return (i915_ggtt_offset(engine->status_page.vma) +
+ I915_GEM_HWS_HANGCHECK_ADDR);
+}
+
static inline u32 intel_hws_seqno_address(struct intel_engine_cs *engine)
{
return (i915_ggtt_offset(engine->status_page.vma) +
@@ -316,6 +322,11 @@ static u32 *gen6_rcs_emit_breadcrumb(struct i915_request *rq, u32 *cs)
*cs++ = rq->timeline->hwsp_offset | PIPE_CONTROL_GLOBAL_GTT;
*cs++ = rq->fence.seqno;
+ *cs++ = GFX_OP_PIPE_CONTROL(4);
+ *cs++ = PIPE_CONTROL_QW_WRITE;
+ *cs++ = hws_hangcheck_address(rq->engine) | PIPE_CONTROL_GLOBAL_GTT;
+ *cs++ = intel_engine_next_hangcheck_seqno(rq->engine);
+
*cs++ = GFX_OP_PIPE_CONTROL(4);
*cs++ = PIPE_CONTROL_QW_WRITE | PIPE_CONTROL_CS_STALL;
*cs++ = intel_hws_seqno_address(rq->engine) | PIPE_CONTROL_GLOBAL_GTT;
@@ -422,6 +433,11 @@ static u32 *gen7_rcs_emit_breadcrumb(struct i915_request *rq, u32 *cs)
*cs++ = rq->timeline->hwsp_offset;
*cs++ = rq->fence.seqno;
+ *cs++ = GFX_OP_PIPE_CONTROL(4);
+ *cs++ = PIPE_CONTROL_QW_WRITE | PIPE_CONTROL_GLOBAL_GTT_IVB;
+ *cs++ = hws_hangcheck_address(rq->engine);
+ *cs++ = intel_engine_next_hangcheck_seqno(rq->engine);
+
*cs++ = GFX_OP_PIPE_CONTROL(4);
*cs++ = (PIPE_CONTROL_QW_WRITE |
PIPE_CONTROL_GLOBAL_GTT_IVB |
@@ -447,12 +463,15 @@ static u32 *gen6_xcs_emit_breadcrumb(struct i915_request *rq, u32 *cs)
*cs++ = I915_GEM_HWS_SEQNO_ADDR | MI_FLUSH_DW_USE_GTT;
*cs++ = rq->fence.seqno;
+ *cs++ = MI_FLUSH_DW | MI_FLUSH_DW_OP_STOREDW | MI_FLUSH_DW_STORE_INDEX;
+ *cs++ = I915_GEM_HWS_HANGCHECK_ADDR | MI_FLUSH_DW_USE_GTT;
+ *cs++ = intel_engine_next_hangcheck_seqno(rq->engine);
+
*cs++ = MI_FLUSH_DW | MI_FLUSH_DW_OP_STOREDW | MI_FLUSH_DW_STORE_INDEX;
*cs++ = I915_GEM_HWS_INDEX_ADDR | MI_FLUSH_DW_USE_GTT;
*cs++ = rq->global_seqno;
*cs++ = MI_USER_INTERRUPT;
- *cs++ = MI_NOOP;
rq->tail = intel_ring_offset(rq, cs);
assert_ring_tail_valid(rq->ring, rq->tail);
@@ -472,6 +491,10 @@ static u32 *gen7_xcs_emit_breadcrumb(struct i915_request *rq, u32 *cs)
*cs++ = I915_GEM_HWS_SEQNO_ADDR | MI_FLUSH_DW_USE_GTT;
*cs++ = rq->fence.seqno;
+ *cs++ = MI_FLUSH_DW | MI_FLUSH_DW_OP_STOREDW | MI_FLUSH_DW_STORE_INDEX;
+ *cs++ = I915_GEM_HWS_HANGCHECK_ADDR | MI_FLUSH_DW_USE_GTT;
+ *cs++ = intel_engine_next_hangcheck_seqno(rq->engine);
+
*cs++ = MI_FLUSH_DW | MI_FLUSH_DW_OP_STOREDW | MI_FLUSH_DW_STORE_INDEX;
*cs++ = I915_GEM_HWS_INDEX_ADDR | MI_FLUSH_DW_USE_GTT;
*cs++ = rq->global_seqno;
@@ -487,6 +510,7 @@ static u32 *gen7_xcs_emit_breadcrumb(struct i915_request *rq, u32 *cs)
*cs++ = 0;
*cs++ = MI_USER_INTERRUPT;
+ *cs++ = MI_NOOP;
rq->tail = intel_ring_offset(rq, cs);
assert_ring_tail_valid(rq->ring, rq->tail);
@@ -930,11 +954,16 @@ static u32 *i9xx_emit_breadcrumb(struct i915_request *rq, u32 *cs)
*cs++ = I915_GEM_HWS_SEQNO_ADDR;
*cs++ = rq->fence.seqno;
+ *cs++ = MI_STORE_DWORD_INDEX;
+ *cs++ = I915_GEM_HWS_HANGCHECK_ADDR;
+ *cs++ = intel_engine_next_hangcheck_seqno(rq->engine);
+
*cs++ = MI_STORE_DWORD_INDEX;
*cs++ = I915_GEM_HWS_INDEX_ADDR;
*cs++ = rq->global_seqno;
*cs++ = MI_USER_INTERRUPT;
+ *cs++ = MI_NOOP;
rq->tail = intel_ring_offset(rq, cs);
assert_ring_tail_valid(rq->ring, rq->tail);
@@ -956,6 +985,10 @@ static u32 *gen5_emit_breadcrumb(struct i915_request *rq, u32 *cs)
*cs++ = I915_GEM_HWS_SEQNO_ADDR;
*cs++ = rq->fence.seqno;
+ *cs++ = MI_STORE_DWORD_INDEX;
+ *cs++ = I915_GEM_HWS_HANGCHECK_ADDR;
+ *cs++ = intel_engine_next_hangcheck_seqno(rq->engine);
+
BUILD_BUG_ON(GEN5_WA_STORES < 1);
for (i = 0; i < GEN5_WA_STORES; i++) {
*cs++ = MI_STORE_DWORD_INDEX;
@@ -964,7 +997,6 @@ static u32 *gen5_emit_breadcrumb(struct i915_request *rq, u32 *cs)
}
*cs++ = MI_USER_INTERRUPT;
- *cs++ = MI_NOOP;
rq->tail = intel_ring_offset(rq, cs);
assert_ring_tail_valid(rq->ring, rq->tail);
@@ -6,6 +6,7 @@
#include <linux/hashtable.h>
#include <linux/irq_work.h>
+#include <linux/random.h>
#include <linux/seqlock.h>
#include "i915_gem_batch_pool.h"
@@ -119,7 +120,8 @@ struct intel_instdone {
struct intel_engine_hangcheck {
u64 acthd;
- u32 seqno;
+ u32 last_seqno;
+ u32 next_seqno;
unsigned long action_timestamp;
struct intel_instdone instdone;
};
@@ -726,6 +728,8 @@ intel_write_status_page(struct intel_engine_cs *engine, int reg, u32 value)
#define I915_GEM_HWS_INDEX_ADDR (I915_GEM_HWS_INDEX * sizeof(u32))
#define I915_GEM_HWS_PREEMPT 0x32
#define I915_GEM_HWS_PREEMPT_ADDR (I915_GEM_HWS_PREEMPT * sizeof(u32))
+#define I915_GEM_HWS_HANGCHECK 0x34
+#define I915_GEM_HWS_HANGCHECK_ADDR (I915_GEM_HWS_HANGCHECK * sizeof(u32))
#define I915_GEM_HWS_SEQNO 0x40
#define I915_GEM_HWS_SEQNO_ADDR (I915_GEM_HWS_SEQNO * sizeof(u32))
#define I915_GEM_HWS_SCRATCH 0x80
@@ -1086,4 +1090,17 @@ static inline bool inject_preempt_hang(struct intel_engine_execlists *execlists)
#endif
+static inline u32
+intel_engine_next_hangcheck_seqno(struct intel_engine_cs *engine)
+{
+ return engine->hangcheck.next_seqno =
+ next_pseudo_random32(engine->hangcheck.next_seqno);
+}
+
+static inline u32
+intel_engine_get_hangcheck_seqno(struct intel_engine_cs *engine)
+{
+ return intel_read_status_page(engine, I915_GEM_HWS_HANGCHECK);
+}
+
#endif /* _INTEL_RINGBUFFER_H_ */
To determine whether an engine has 'stuck', we simply check whether or not is still on the same seqno for several seconds. To keep this simple mechanism intact over the loss of a global seqno, we can simply add a new global heartbeat seqno instead. As we cannot know the sequence in which requests will then be completed, we use a primitive random number generator instead (with a cycle long enough to not matter over an interval of a few thousand requests between hangcheck samples). The alternative to using a dedicated seqno on every request is to issue a heartbeat request and query its progress through the system. Sadly this requires us to reduce struct_mutex so that we can issue requests without requiring that bkl. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> --- drivers/gpu/drm/i915/i915_debugfs.c | 7 ++--- drivers/gpu/drm/i915/intel_engine_cs.c | 5 ++-- drivers/gpu/drm/i915/intel_hangcheck.c | 6 ++--- drivers/gpu/drm/i915/intel_lrc.c | 15 +++++++++++ drivers/gpu/drm/i915/intel_ringbuffer.c | 36 +++++++++++++++++++++++-- drivers/gpu/drm/i915/intel_ringbuffer.h | 19 ++++++++++++- 6 files changed, 77 insertions(+), 11 deletions(-)