The current algorithm to read out devcoredump is O(N*N) where N is the size of coredump due to usage of the drm_coredump_printer in xe_devcoredump_read. Switch to a O(N) algorithm which prints the devcoredump into a readable format in snapshot work and update xe_devcoredump_read to memcpy from the readable format directly.
v2: - Fix double free on devcoredump removal (Testing) - Set read_data_size after snap work flush - Adjust remaining in iterator upon realloc (Testing) - Set read_data upon realloc (Testing) v3: - Kernel doc v4: - Two pass algorithm to determine size (Maarten) v5: - Use scope for reading variables (Johnathan) Reported-by: Paulo Zanoni <paulo.r.zan...@intel.com> Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/2408 Cc: Rodrigo Vivi <rodrigo.v...@intel.com> Cc: Maarten Lankhorst <maarten.lankho...@linux.intel.com> Signed-off-by: Matthew Brost <matthew.br...@intel.com> Reviewed-by: Jonathan Cavitt <jonathan.cav...@intel.com> --- drivers/gpu/drm/xe/xe_devcoredump.c | 111 ++++++++++++++++------ drivers/gpu/drm/xe/xe_devcoredump_types.h | 8 ++ 2 files changed, 88 insertions(+), 31 deletions(-) diff --git a/drivers/gpu/drm/xe/xe_devcoredump.c b/drivers/gpu/drm/xe/xe_devcoredump.c index d8d8ca2c19d3..bdb76e834e4c 100644 --- a/drivers/gpu/drm/xe/xe_devcoredump.c +++ b/drivers/gpu/drm/xe/xe_devcoredump.c @@ -66,22 +66,9 @@ static struct xe_guc *exec_queue_to_guc(struct xe_exec_queue *q) return &q->gt->uc.guc; } -static void xe_devcoredump_deferred_snap_work(struct work_struct *work) -{ - struct xe_devcoredump_snapshot *ss = container_of(work, typeof(*ss), work); - - /* keep going if fw fails as we still want to save the memory and SW data */ - if (xe_force_wake_get(gt_to_fw(ss->gt), XE_FORCEWAKE_ALL)) - xe_gt_info(ss->gt, "failed to get forcewake for coredump capture\n"); - xe_vm_snapshot_capture_delayed(ss->vm); - xe_guc_exec_queue_snapshot_capture_delayed(ss->ge); - xe_force_wake_put(gt_to_fw(ss->gt), XE_FORCEWAKE_ALL); -} - -static ssize_t xe_devcoredump_read(char *buffer, loff_t offset, - size_t count, void *data, size_t datalen) +static ssize_t __xe_devcoredump_read(char *buffer, size_t count, + struct xe_devcoredump *coredump) { - struct xe_devcoredump *coredump = data; struct xe_device *xe; struct xe_devcoredump_snapshot *ss; struct drm_printer p; @@ -89,18 +76,11 @@ static ssize_t xe_devcoredump_read(char *buffer, loff_t offset, struct timespec64 ts; int i; - if (!coredump) - return -ENODEV; - xe = coredump_to_xe(coredump); ss = &coredump->snapshot; - /* Ensure delayed work is captured before continuing */ - flush_work(&ss->work); - iter.data = buffer; - iter.offset = 0; - iter.start = offset; + iter.start = 0; iter.remain = count; p = drm_coredump_printer(&iter); @@ -134,10 +114,83 @@ static ssize_t xe_devcoredump_read(char *buffer, loff_t offset, return count - iter.remain; } +static void xe_devcoredump_snapshot_free(struct xe_devcoredump_snapshot *ss) +{ + int i; + + xe_guc_ct_snapshot_free(ss->ct); + ss->ct = NULL; + + xe_guc_exec_queue_snapshot_free(ss->ge); + ss->ge = NULL; + + xe_sched_job_snapshot_free(ss->job); + ss->job = NULL; + + for (i = 0; i < XE_NUM_HW_ENGINES; i++) + if (ss->hwe[i]) { + xe_hw_engine_snapshot_free(ss->hwe[i]); + ss->hwe[i] = NULL; + } + + xe_vm_snapshot_free(ss->vm); + ss->vm = NULL; +} + +static void xe_devcoredump_deferred_snap_work(struct work_struct *work) +{ + struct xe_devcoredump_snapshot *ss = container_of(work, typeof(*ss), work); + struct xe_devcoredump *coredump = container_of(ss, typeof(*coredump), snapshot); + + /* keep going if fw fails as we still want to save the memory and SW data */ + if (xe_force_wake_get(gt_to_fw(ss->gt), XE_FORCEWAKE_ALL)) + xe_gt_info(ss->gt, "failed to get forcewake for coredump capture\n"); + xe_vm_snapshot_capture_delayed(ss->vm); + xe_guc_exec_queue_snapshot_capture_delayed(ss->ge); + xe_force_wake_put(gt_to_fw(ss->gt), XE_FORCEWAKE_ALL); + + /* Calculate devcoredump size */ + ss->read.size = __xe_devcoredump_read(NULL, INT_MAX, coredump); + + ss->read.buffer = kvmalloc(ss->read.size, GFP_USER); + if (!ss->read.buffer) + return; + + __xe_devcoredump_read(ss->read.buffer, ss->read.size, coredump); + xe_devcoredump_snapshot_free(ss); +} + +static ssize_t xe_devcoredump_read(char *buffer, loff_t offset, + size_t count, void *data, size_t datalen) +{ + struct xe_devcoredump *coredump = data; + struct xe_devcoredump_snapshot *ss; + ssize_t byte_copied; + + if (!coredump) + return -ENODEV; + + ss = &coredump->snapshot; + + /* Ensure delayed work is captured before continuing */ + flush_work(&ss->work); + + if (!ss->read.buffer) + return -ENODEV; + + if (offset >= ss->read.size) + return 0; + + byte_copied = count < ss->read.size - offset ? count : + ss->read.size - offset; + memcpy(buffer, ss->read.buffer + offset, byte_copied); + + return byte_copied; +} + static void xe_devcoredump_free(void *data) { struct xe_devcoredump *coredump = data; - int i; /* Our device is gone. Nothing to do... */ if (!data || !coredump_to_xe(coredump)) @@ -145,13 +198,8 @@ static void xe_devcoredump_free(void *data) cancel_work_sync(&coredump->snapshot.work); - xe_guc_ct_snapshot_free(coredump->snapshot.ct); - xe_guc_exec_queue_snapshot_free(coredump->snapshot.ge); - xe_sched_job_snapshot_free(coredump->snapshot.job); - for (i = 0; i < XE_NUM_HW_ENGINES; i++) - if (coredump->snapshot.hwe[i]) - xe_hw_engine_snapshot_free(coredump->snapshot.hwe[i]); - xe_vm_snapshot_free(coredump->snapshot.vm); + xe_devcoredump_snapshot_free(&coredump->snapshot); + kvfree(coredump->snapshot.read.buffer); /* To prevent stale data on next snapshot, clear everything */ memset(&coredump->snapshot, 0, sizeof(coredump->snapshot)); @@ -260,4 +308,5 @@ int xe_devcoredump_init(struct xe_device *xe) { return devm_add_action_or_reset(xe->drm.dev, xe_driver_devcoredump_fini, &xe->drm); } + #endif diff --git a/drivers/gpu/drm/xe/xe_devcoredump_types.h b/drivers/gpu/drm/xe/xe_devcoredump_types.h index 923cdf72a816..440d05d77a5a 100644 --- a/drivers/gpu/drm/xe/xe_devcoredump_types.h +++ b/drivers/gpu/drm/xe/xe_devcoredump_types.h @@ -46,6 +46,14 @@ struct xe_devcoredump_snapshot { struct xe_sched_job_snapshot *job; /** @vm: Snapshot of VM state */ struct xe_vm_snapshot *vm; + + /** @read: devcoredump in human readable format */ + struct { + /** @read.size: size of devcoredump in human readable format */ + ssize_t size; + /** @read.buffer: buffer of devcoredump in human readable format */ + char *buffer; + } read; }; /** -- 2.34.1
