[RFC 5/5] drm/xe: Support devcoredump capture from dead CT handler

[John.C.Harrison@Intel.com]

From: John Harrison <John.C.Harrison@Intel.com>

The dead CT handler was doing a locally rolled fake devcoredump
capture and print. Replace that with support for calling the genuine
devcoredump code to do the capture and print instead.

Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
---
 drivers/gpu/drm/xe/xe_devcoredump.c  |  8 +++-
 drivers/gpu/drm/xe/xe_devcoredump.h  |  2 +
 drivers/gpu/drm/xe/xe_guc_ct.c       | 57 +++++++++++++---------------
 drivers/gpu/drm/xe/xe_guc_ct_types.h |  6 +--
 4 files changed, 38 insertions(+), 35 deletions(-)

diff --git a/drivers/gpu/drm/xe/xe_devcoredump.c b/drivers/gpu/drm/xe/xe_devcoredump.c
index 146b5cd4fbe6..d3a5cb82bf72 100644
--- a/drivers/gpu/drm/xe/xe_devcoredump.c
+++ b/drivers/gpu/drm/xe/xe_devcoredump.c
@@ -223,7 +223,7 @@ static ssize_t xe_devcoredump_read(char *buffer, loff_t offset,
 	return byte_copied;
 }
 
-static void xe_devcoredump_free(void *data)
+void xe_devcoredump_free(void *data)
 {
 	struct xe_devcoredump *coredump = data;
 
@@ -376,6 +376,12 @@ static void devcoredump_snapshot_for_thing(struct xe_devcoredump *coredump,
 	dma_fence_end_signalling(cookie);
 }
 
+void xe_devcoredump_snapshot_gt(struct xe_devcoredump *coredump, struct xe_gt *gt)
+{
+	coredump->xe = gt_to_xe(gt);
+	devcoredump_snapshot_for_thing(coredump, gt, NULL, false);
+}
+
 static void devcoredump_for_thing(struct xe_device *_xe, struct xe_gt *gt,
 				  struct xe_sched_job *job, bool want_work)
 {
diff --git a/drivers/gpu/drm/xe/xe_devcoredump.h b/drivers/gpu/drm/xe/xe_devcoredump.h
index 1d2f9bbd4ebe..91337432bf78 100644
--- a/drivers/gpu/drm/xe/xe_devcoredump.h
+++ b/drivers/gpu/drm/xe/xe_devcoredump.h
@@ -31,6 +31,8 @@ static inline int xe_devcoredump_init(struct xe_device *xe)
 #endif
 
 void xe_devcoredump_print(struct drm_printer *p, struct xe_devcoredump *coredump);
+void xe_devcoredump_snapshot_gt(struct xe_devcoredump *coredump, struct xe_gt *gt);
+void xe_devcoredump_free(void *data);
 void xe_print_blob_ascii85(struct drm_printer *p, const char *prefix,
 			   const void *blob, size_t offset, size_t size);
 
diff --git a/drivers/gpu/drm/xe/xe_guc_ct.c b/drivers/gpu/drm/xe/xe_guc_ct.c
index 2eeadcdf7bc3..a738dcf90aa9 100644
--- a/drivers/gpu/drm/xe/xe_guc_ct.c
+++ b/drivers/gpu/drm/xe/xe_guc_ct.c
@@ -1800,11 +1800,10 @@ void xe_guc_ct_print(struct xe_guc_ct *ct, struct drm_printer *p, bool want_ctb)
 #if IS_ENABLED(CONFIG_DRM_XE_DEBUG)
 static void ct_dead_capture(struct xe_guc_ct *ct, struct guc_ctb *ctb, u32 reason_code)
 {
-	struct xe_guc_log_snapshot *snapshot_log;
-	struct xe_guc_ct_snapshot *snapshot_ct;
-	struct xe_guc *guc = ct_to_guc(ct);
+	struct xe_devcoredump *coredump;
 	unsigned long flags;
 	bool have_capture;
+	struct xe_gt *gt = ct_to_gt(ct);
 
 	if (ctb)
 		ctb->info.broken = true;
@@ -1825,29 +1824,36 @@ static void ct_dead_capture(struct xe_guc_ct *ct, struct guc_ctb *ctb, u32 reaso
 	if (have_capture)
 		return;
 
-	snapshot_log = xe_guc_log_snapshot_capture(&guc->log, true);
-	snapshot_ct = xe_guc_ct_snapshot_capture((ct));
+	coredump = kzalloc(sizeof(*coredump), GFP_ATOMIC);
+	if (!coredump) {
+		xe_gt_err(gt, "Failed to allocate coredump for dead CT capture!\n");
+		return;
+	}
+
+	xe_devcoredump_snapshot_gt(coredump, gt);
 
 	spin_lock_irqsave(&ct->dead.lock, flags);
 
-	if (ct->dead.snapshot_log || ct->dead.snapshot_ct) {
-		xe_gt_err(ct_to_gt(ct), "Got unexpected dead CT capture!\n");
-		xe_guc_log_snapshot_free(snapshot_log);
-		xe_guc_ct_snapshot_free(snapshot_ct);
+	if (ct->dead.coredump) {
+		xe_gt_err(gt, "Got unexpected dead CT capture!\n");
 	} else {
-		ct->dead.snapshot_log = snapshot_log;
-		ct->dead.snapshot_ct = snapshot_ct;
+		ct->dead.coredump = coredump;
+		coredump = NULL;
 	}
 
 	spin_unlock_irqrestore(&ct->dead.lock, flags);
 
-	queue_work(system_unbound_wq, &(ct)->dead.worker);
+	queue_work(system_unbound_wq, &ct->dead.worker);
+
+	if (coredump) {
+		xe_devcoredump_free(coredump);
+		kfree(coredump);
+	}
 }
 
 static void ct_dead_print(struct xe_dead_ct *dead)
 {
 	struct xe_guc_ct *ct = container_of(dead, struct xe_guc_ct, dead);
-	struct xe_device *xe = ct_to_xe(ct);
 	struct xe_gt *gt = ct_to_gt(ct);
 	static int g_count;
 	struct drm_printer ip = xe_gt_info_printer(gt);
@@ -1860,18 +1866,8 @@ static void ct_dead_print(struct xe_dead_ct *dead)
 
 	drm_printf(&lp, "CTB is dead - reason=0x%X\n", dead->reason);
 
-	/* Can't generate a genuine core dump at this point, so just do the good bits */
-	drm_puts(&lp, "**** Xe Device Coredump ****\n");
-	xe_device_snapshot_print(xe, &lp);
-
-	drm_printf(&lp, "**** GT #%d ****\n", gt->info.id);
-	drm_printf(&lp, "\tTile: %d\n", gt->tile->id);
-
-	drm_puts(&lp, "**** GuC Log ****\n");
-	xe_guc_log_snapshot_print(dead->snapshot_log, &lp);
-
-	drm_puts(&lp, "**** GuC CT ****\n");
-	xe_guc_ct_snapshot_print(dead->snapshot_ct, &lp);
+	if (dead->coredump)
+		xe_devcoredump_print(&lp, dead->coredump);
 
 	drm_puts(&lp, "Done.\n");
 }
@@ -1879,6 +1875,7 @@ static void ct_dead_print(struct xe_dead_ct *dead)
 static void ct_dead_worker_func(struct work_struct *w)
 {
 	struct xe_guc_ct *ct = container_of(w, struct xe_guc_ct, dead.worker);
+	struct xe_devcoredump *coredump;
 
 	if (!ct->dead.reported) {
 		ct->dead.reported = true;
@@ -1886,11 +1883,8 @@ static void ct_dead_worker_func(struct work_struct *w)
 	}
 
 	spin_lock_irq(&ct->dead.lock);
-
-	xe_guc_log_snapshot_free(ct->dead.snapshot_log);
-	ct->dead.snapshot_log = NULL;
-	xe_guc_ct_snapshot_free(ct->dead.snapshot_ct);
-	ct->dead.snapshot_ct = NULL;
+	coredump = ct->dead.coredump;
+	ct->dead.coredump = NULL;
 
 	if (ct->dead.reason & (1 << CT_DEAD_STATE_REARM)) {
 		/* A reset has occurred so re-arm the error reporting */
@@ -1899,5 +1893,8 @@ static void ct_dead_worker_func(struct work_struct *w)
 	}
 
 	spin_unlock_irq(&ct->dead.lock);
+
+	xe_devcoredump_free(coredump);
+	kfree(coredump);
 }
 #endif
diff --git a/drivers/gpu/drm/xe/xe_guc_ct_types.h b/drivers/gpu/drm/xe/xe_guc_ct_types.h
index 8e1b9d981d61..7131dd6a8366 100644
--- a/drivers/gpu/drm/xe/xe_guc_ct_types.h
+++ b/drivers/gpu/drm/xe/xe_guc_ct_types.h
@@ -99,10 +99,8 @@ struct xe_dead_ct {
 	bool reported;
 	/** @worker: worker thread to get out of interrupt context before dumping */
 	struct work_struct worker;
-	/** snapshot_ct: copy of CT state and CTB content at point of error */
-	struct xe_guc_ct_snapshot *snapshot_ct;
-	/** snapshot_log: copy of GuC log at point of error */
-	struct xe_guc_log_snapshot *snapshot_log;
+	/** coredump: copy of system state at point of error */
+	struct xe_devcoredump *coredump;
 };
 #endif
 
-- 
2.47.0