drm/xe: Move job creation out of the struct xe_migrate::job_mutex

In order to be able to run gpu jobs from reclaim context,
move job creation (where allocation takes place) out of the
struct xe_migrate::job_mutex, and prime that mutex as reclaim
tainted.

Jobs that may need to run from reclaim context include
CCS metadata extraction at shrinking time.

Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240527135912.152156-6-thomas.hellstrom@linux.intel.com

diff --git a/drivers/gpu/drm/xe/xe_migrate.c b/drivers/gpu/drm/xe/xe_migrate.c
index bacb23de411b06c09824397a94303c8d3cdb60fd..cccffaf3db062aa689ed34c3167fed5e908deed1 100644 (file)
--- a/drivers/gpu/drm/xe/xe_migrate.c
+++ b/drivers/gpu/drm/xe/xe_migrate.c
@@ -383,6 +383,9 @@ struct xe_migrate *xe_migrate_init(struct xe_tile *tile)
        }
 
        mutex_init(&m->job_mutex);
+       fs_reclaim_acquire(GFP_KERNEL);
+       might_lock(&m->job_mutex);
+       fs_reclaim_release(GFP_KERNEL);
 
        err = drmm_add_action_or_reset(&xe->drm, xe_migrate_fini, m);
        if (err)
@@ -807,7 +810,6 @@ struct dma_fence *xe_migrate_copy(struct xe_migrate *m,
                                                  IS_DGFX(xe) ? dst_is_vram : dst_is_pltt,
                                                  src_L0, ccs_ofs, copy_ccs);
 
-               mutex_lock(&m->job_mutex);
                job = xe_bb_create_migration_job(m->q, bb,
                                                 xe_migrate_batch_base(m, usm),
                                                 update_idx);
@@ -827,6 +829,7 @@ struct dma_fence *xe_migrate_copy(struct xe_migrate *m,
                                goto err_job;
                }
 
+               mutex_lock(&m->job_mutex);
                xe_sched_job_arm(job);
                dma_fence_put(fence);
                fence = dma_fence_get(&job->drm.s_fence->finished);
@@ -844,7 +847,6 @@ struct dma_fence *xe_migrate_copy(struct xe_migrate *m,
 err_job:
                xe_sched_job_put(job);
 err:
-               mutex_unlock(&m->job_mutex);
                xe_bb_free(bb, NULL);
 
 err_sync:
@@ -1044,7 +1046,6 @@ struct dma_fence *xe_migrate_clear(struct xe_migrate *m,
                        flush_flags = MI_FLUSH_DW_CCS;
                }
 
-               mutex_lock(&m->job_mutex);
                job = xe_bb_create_migration_job(m->q, bb,
                                                 xe_migrate_batch_base(m, usm),
                                                 update_idx);
@@ -1067,6 +1068,7 @@ struct dma_fence *xe_migrate_clear(struct xe_migrate *m,
                                goto err_job;
                }
 
+               mutex_lock(&m->job_mutex);
                xe_sched_job_arm(job);
                dma_fence_put(fence);
                fence = dma_fence_get(&job->drm.s_fence->finished);
@@ -1083,7 +1085,6 @@ struct dma_fence *xe_migrate_clear(struct xe_migrate *m,
 err_job:
                xe_sched_job_put(job);
 err:
-               mutex_unlock(&m->job_mutex);
                xe_bb_free(bb, NULL);
 err_sync:
                /* Sync partial copies if any. FIXME: job_mutex? */
@@ -1377,9 +1378,6 @@ xe_migrate_update_pgtables(struct xe_migrate *m,
                        write_pgtable(tile, bb, 0, &updates[i], pt_update);
        }
 
-       if (!q)
-               mutex_lock(&m->job_mutex);
-
        job = xe_bb_create_migration_job(q ?: m->q, bb,
                                         xe_migrate_batch_base(m, usm),
                                         update_idx);
@@ -1420,6 +1418,9 @@ xe_migrate_update_pgtables(struct xe_migrate *m,
                if (err)
                        goto err_job;
        }
+       if (!q)
+               mutex_lock(&m->job_mutex);
+
        xe_sched_job_arm(job);
        fence = dma_fence_get(&job->drm.s_fence->finished);
        xe_sched_job_push(job);
@@ -1435,8 +1436,6 @@ xe_migrate_update_pgtables(struct xe_migrate *m,
 err_job:
        xe_sched_job_put(job);
 err_bb:
-       if (!q)
-               mutex_unlock(&m->job_mutex);
        xe_bb_free(bb, NULL);
 err:
        drm_suballoc_free(sa_bo, NULL);