xref: /linux/drivers/gpu/drm/xe/xe_devcoredump.c (revision 001821b0e79716c4e17c71d8e053a23599a7a508)
1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright © 2023 Intel Corporation
4  */
5 
6 #include "xe_devcoredump.h"
7 #include "xe_devcoredump_types.h"
8 
9 #include <linux/devcoredump.h>
10 #include <generated/utsrelease.h>
11 
12 #include <drm/drm_managed.h>
13 
14 #include "xe_device.h"
15 #include "xe_exec_queue.h"
16 #include "xe_force_wake.h"
17 #include "xe_gt.h"
18 #include "xe_gt_printk.h"
19 #include "xe_guc_ct.h"
20 #include "xe_guc_submit.h"
21 #include "xe_hw_engine.h"
22 #include "xe_sched_job.h"
23 #include "xe_vm.h"
24 
25 /**
26  * DOC: Xe device coredump
27  *
28  * Devices overview:
29  * Xe uses dev_coredump infrastructure for exposing the crash errors in a
30  * standardized way.
31  * devcoredump exposes a temporary device under /sys/class/devcoredump/
32  * which is linked with our card device directly.
33  * The core dump can be accessed either from
34  * /sys/class/drm/card<n>/device/devcoredump/ or from
35  * /sys/class/devcoredump/devcd<m> where
36  * /sys/class/devcoredump/devcd<m>/failing_device is a link to
37  * /sys/class/drm/card<n>/device/.
38  *
39  * Snapshot at hang:
40  * The 'data' file is printed with a drm_printer pointer at devcoredump read
41  * time. For this reason, we need to take snapshots from when the hang has
42  * happened, and not only when the user is reading the file. Otherwise the
43  * information is outdated since the resets might have happened in between.
44  *
45  * 'First' failure snapshot:
46  * In general, the first hang is the most critical one since the following hangs
47  * can be a consequence of the initial hang. For this reason we only take the
48  * snapshot of the 'first' failure and ignore subsequent calls of this function,
49  * at least while the coredump device is alive. Dev_coredump has a delayed work
50  * queue that will eventually delete the device and free all the dump
51  * information.
52  */
53 
54 #ifdef CONFIG_DEV_COREDUMP
55 
56 static struct xe_device *coredump_to_xe(const struct xe_devcoredump *coredump)
57 {
58 	return container_of(coredump, struct xe_device, devcoredump);
59 }
60 
61 static struct xe_guc *exec_queue_to_guc(struct xe_exec_queue *q)
62 {
63 	return &q->gt->uc.guc;
64 }
65 
66 static void xe_devcoredump_deferred_snap_work(struct work_struct *work)
67 {
68 	struct xe_devcoredump_snapshot *ss = container_of(work, typeof(*ss), work);
69 
70 	/* keep going if fw fails as we still want to save the memory and SW data */
71 	if (xe_force_wake_get(gt_to_fw(ss->gt), XE_FORCEWAKE_ALL))
72 		xe_gt_info(ss->gt, "failed to get forcewake for coredump capture\n");
73 	xe_vm_snapshot_capture_delayed(ss->vm);
74 	xe_guc_exec_queue_snapshot_capture_delayed(ss->ge);
75 	xe_force_wake_put(gt_to_fw(ss->gt), XE_FORCEWAKE_ALL);
76 }
77 
78 static ssize_t xe_devcoredump_read(char *buffer, loff_t offset,
79 				   size_t count, void *data, size_t datalen)
80 {
81 	struct xe_devcoredump *coredump = data;
82 	struct xe_device *xe;
83 	struct xe_devcoredump_snapshot *ss;
84 	struct drm_printer p;
85 	struct drm_print_iterator iter;
86 	struct timespec64 ts;
87 	int i;
88 
89 	if (!coredump)
90 		return -ENODEV;
91 
92 	xe = coredump_to_xe(coredump);
93 	ss = &coredump->snapshot;
94 
95 	/* Ensure delayed work is captured before continuing */
96 	flush_work(&ss->work);
97 
98 	iter.data = buffer;
99 	iter.offset = 0;
100 	iter.start = offset;
101 	iter.remain = count;
102 
103 	p = drm_coredump_printer(&iter);
104 
105 	drm_printf(&p, "**** Xe Device Coredump ****\n");
106 	drm_printf(&p, "kernel: " UTS_RELEASE "\n");
107 	drm_printf(&p, "module: " KBUILD_MODNAME "\n");
108 
109 	ts = ktime_to_timespec64(ss->snapshot_time);
110 	drm_printf(&p, "Snapshot time: %lld.%09ld\n", ts.tv_sec, ts.tv_nsec);
111 	ts = ktime_to_timespec64(ss->boot_time);
112 	drm_printf(&p, "Uptime: %lld.%09ld\n", ts.tv_sec, ts.tv_nsec);
113 	xe_device_snapshot_print(xe, &p);
114 
115 	drm_printf(&p, "\n**** GuC CT ****\n");
116 	xe_guc_ct_snapshot_print(coredump->snapshot.ct, &p);
117 	xe_guc_exec_queue_snapshot_print(coredump->snapshot.ge, &p);
118 
119 	drm_printf(&p, "\n**** Job ****\n");
120 	xe_sched_job_snapshot_print(coredump->snapshot.job, &p);
121 
122 	drm_printf(&p, "\n**** HW Engines ****\n");
123 	for (i = 0; i < XE_NUM_HW_ENGINES; i++)
124 		if (coredump->snapshot.hwe[i])
125 			xe_hw_engine_snapshot_print(coredump->snapshot.hwe[i],
126 						    &p);
127 	drm_printf(&p, "\n**** VM state ****\n");
128 	xe_vm_snapshot_print(coredump->snapshot.vm, &p);
129 
130 	return count - iter.remain;
131 }
132 
133 static void xe_devcoredump_free(void *data)
134 {
135 	struct xe_devcoredump *coredump = data;
136 	int i;
137 
138 	/* Our device is gone. Nothing to do... */
139 	if (!data || !coredump_to_xe(coredump))
140 		return;
141 
142 	cancel_work_sync(&coredump->snapshot.work);
143 
144 	xe_guc_ct_snapshot_free(coredump->snapshot.ct);
145 	xe_guc_exec_queue_snapshot_free(coredump->snapshot.ge);
146 	xe_sched_job_snapshot_free(coredump->snapshot.job);
147 	for (i = 0; i < XE_NUM_HW_ENGINES; i++)
148 		if (coredump->snapshot.hwe[i])
149 			xe_hw_engine_snapshot_free(coredump->snapshot.hwe[i]);
150 	xe_vm_snapshot_free(coredump->snapshot.vm);
151 
152 	/* To prevent stale data on next snapshot, clear everything */
153 	memset(&coredump->snapshot, 0, sizeof(coredump->snapshot));
154 	coredump->captured = false;
155 	drm_info(&coredump_to_xe(coredump)->drm,
156 		 "Xe device coredump has been deleted.\n");
157 }
158 
159 static void devcoredump_snapshot(struct xe_devcoredump *coredump,
160 				 struct xe_sched_job *job)
161 {
162 	struct xe_devcoredump_snapshot *ss = &coredump->snapshot;
163 	struct xe_exec_queue *q = job->q;
164 	struct xe_guc *guc = exec_queue_to_guc(q);
165 	struct xe_hw_engine *hwe;
166 	enum xe_hw_engine_id id;
167 	u32 adj_logical_mask = q->logical_mask;
168 	u32 width_mask = (0x1 << q->width) - 1;
169 	int i;
170 	bool cookie;
171 
172 	ss->snapshot_time = ktime_get_real();
173 	ss->boot_time = ktime_get_boottime();
174 
175 	ss->gt = q->gt;
176 	INIT_WORK(&ss->work, xe_devcoredump_deferred_snap_work);
177 
178 	cookie = dma_fence_begin_signalling();
179 	for (i = 0; q->width > 1 && i < XE_HW_ENGINE_MAX_INSTANCE;) {
180 		if (adj_logical_mask & BIT(i)) {
181 			adj_logical_mask |= width_mask << i;
182 			i += q->width;
183 		} else {
184 			++i;
185 		}
186 	}
187 
188 	/* keep going if fw fails as we still want to save the memory and SW data */
189 	if (xe_force_wake_get(gt_to_fw(q->gt), XE_FORCEWAKE_ALL))
190 		xe_gt_info(ss->gt, "failed to get forcewake for coredump capture\n");
191 
192 	coredump->snapshot.ct = xe_guc_ct_snapshot_capture(&guc->ct, true);
193 	coredump->snapshot.ge = xe_guc_exec_queue_snapshot_capture(q);
194 	coredump->snapshot.job = xe_sched_job_snapshot_capture(job);
195 	coredump->snapshot.vm = xe_vm_snapshot_capture(q->vm);
196 
197 	for_each_hw_engine(hwe, q->gt, id) {
198 		if (hwe->class != q->hwe->class ||
199 		    !(BIT(hwe->logical_instance) & adj_logical_mask)) {
200 			coredump->snapshot.hwe[id] = NULL;
201 			continue;
202 		}
203 		coredump->snapshot.hwe[id] = xe_hw_engine_snapshot_capture(hwe);
204 	}
205 
206 	queue_work(system_unbound_wq, &ss->work);
207 
208 	xe_force_wake_put(gt_to_fw(q->gt), XE_FORCEWAKE_ALL);
209 	dma_fence_end_signalling(cookie);
210 }
211 
212 /**
213  * xe_devcoredump - Take the required snapshots and initialize coredump device.
214  * @job: The faulty xe_sched_job, where the issue was detected.
215  *
216  * This function should be called at the crash time within the serialized
217  * gt_reset. It is skipped if we still have the core dump device available
218  * with the information of the 'first' snapshot.
219  */
220 void xe_devcoredump(struct xe_sched_job *job)
221 {
222 	struct xe_device *xe = gt_to_xe(job->q->gt);
223 	struct xe_devcoredump *coredump = &xe->devcoredump;
224 
225 	if (coredump->captured) {
226 		drm_dbg(&xe->drm, "Multiple hangs are occurring, but only the first snapshot was taken\n");
227 		return;
228 	}
229 
230 	coredump->captured = true;
231 	devcoredump_snapshot(coredump, job);
232 
233 	drm_info(&xe->drm, "Xe device coredump has been created\n");
234 	drm_info(&xe->drm, "Check your /sys/class/drm/card%d/device/devcoredump/data\n",
235 		 xe->drm.primary->index);
236 
237 	dev_coredumpm(xe->drm.dev, THIS_MODULE, coredump, 0, GFP_KERNEL,
238 		      xe_devcoredump_read, xe_devcoredump_free);
239 }
240 
241 static void xe_driver_devcoredump_fini(struct drm_device *drm, void *arg)
242 {
243 	dev_coredump_put(drm->dev);
244 }
245 
246 int xe_devcoredump_init(struct xe_device *xe)
247 {
248 	return drmm_add_action_or_reset(&xe->drm, xe_driver_devcoredump_fini, xe);
249 }
250 #endif
251