drm/xe/vf: Refactor CCS save/restore to use default migration context

Previously, CCS save/restore operations created separate migration
contexts with new VM memory allocations, resulting in significant
overhead.

This commit eliminates redundant context creation reusing the default
migration context by registering new execution queues for CCS save and
restore on the existing migrate VM.

Signed-off-by: Satyanarayana K V P <satyanarayana.k.v.p@intel.com>
Suggested-by: Matthew Brost <matthew.brost@intel.com>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: John Harrison <John.C.Harrison@Intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Stuart Summers <stuart.summers@intel.com>
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Link: https://lore.kernel.org/r/20250808073628.32745-2-satyanarayana.k.v.p@intel.com

diff --git a/drivers/gpu/drm/xe/xe_exec_queue.c b/drivers/gpu/drm/xe/xe_exec_queue.c
index 6c176183ed58bbb6797a10fe174eab59c14e56e7..2d10a53f701da9a122c16d44d5f99b12cdc42a74 100644 (file)
--- a/drivers/gpu/drm/xe/xe_exec_queue.c
+++ b/drivers/gpu/drm/xe/xe_exec_queue.c
@@ -789,6 +789,21 @@ int xe_exec_queue_get_property_ioctl(struct drm_device *dev, void *data,
        return ret;
 }
 
+/**
+ * xe_exec_queue_lrc() - Get the LRC from exec queue.
+ * @q: The exec_queue.
+ *
+ * Retrieves the primary LRC for the exec queue. Note that this function
+ * returns only the first LRC instance, even when multiple parallel LRCs
+ * are configured.
+ *
+ * Return: Pointer to LRC on success, error on failure
+ */
+struct xe_lrc *xe_exec_queue_lrc(struct xe_exec_queue *q)
+{
+       return q->lrc[0];
+}
+
 /**
  * xe_exec_queue_is_lr() - Whether an exec_queue is long-running
  * @q: The exec_queue

diff --git a/drivers/gpu/drm/xe/xe_exec_queue.h b/drivers/gpu/drm/xe/xe_exec_queue.h
index 4d416f23001cfa564cda780e2cc1a01ceaa9ca2e..15ec852e7f7e78fcfe4fbaa22709601d8287b803 100644 (file)
--- a/drivers/gpu/drm/xe/xe_exec_queue.h
+++ b/drivers/gpu/drm/xe/xe_exec_queue.h
@@ -94,4 +94,5 @@ int xe_exec_queue_contexts_hwsp_rebase(struct xe_exec_queue *q, void *scratch);
 
 void xe_exec_queue_jobs_ring_restore(struct xe_exec_queue *q);
 
+struct xe_lrc *xe_exec_queue_lrc(struct xe_exec_queue *q);
 #endif

diff --git a/drivers/gpu/drm/xe/xe_migrate.c b/drivers/gpu/drm/xe/xe_migrate.c
index 4effe10d815bd3d704d05b7d132d7c74b8561092..ac9f4d4988d2f3a4e74aef1065ce5c07438b8750 100644 (file)
--- a/drivers/gpu/drm/xe/xe_migrate.c
+++ b/drivers/gpu/drm/xe/xe_migrate.c
@@ -951,7 +951,7 @@ err_sync:
 }
 
 /**
- * xe_get_migrate_lrc() - Get the LRC from migrate context.
+ * xe_migrate_lrc() - Get the LRC from migrate context.
  * @migrate: Migrate context.
  *
  * Return: Pointer to LRC on success, error on failure
@@ -961,14 +961,15 @@ struct xe_lrc *xe_migrate_lrc(struct xe_migrate *migrate)
        return migrate->q->lrc[0];
 }
 
-static int emit_flush_invalidate(struct xe_migrate *m, u32 *dw, int i,
+static int emit_flush_invalidate(struct xe_exec_queue *q, u32 *dw, int i,
                                 u32 flags)
 {
+       struct xe_lrc *lrc = xe_exec_queue_lrc(q);
        dw[i++] = MI_FLUSH_DW | MI_INVALIDATE_TLB | MI_FLUSH_DW_OP_STOREDW |
                  MI_FLUSH_IMM_DW | flags;
-       dw[i++] = lower_32_bits(xe_lrc_start_seqno_ggtt_addr(xe_migrate_lrc(m))) |
+       dw[i++] = lower_32_bits(xe_lrc_start_seqno_ggtt_addr(lrc)) |
                  MI_FLUSH_DW_USE_GTT;
-       dw[i++] = upper_32_bits(xe_lrc_start_seqno_ggtt_addr(xe_migrate_lrc(m)));
+       dw[i++] = upper_32_bits(xe_lrc_start_seqno_ggtt_addr(lrc));
        dw[i++] = MI_NOOP;
        dw[i++] = MI_NOOP;
 
@@ -977,7 +978,8 @@ static int emit_flush_invalidate(struct xe_migrate *m, u32 *dw, int i,
 
 /**
  * xe_migrate_ccs_rw_copy() - Copy content of TTM resources.
- * @m: The migration context.
+ * @tile: Tile whose migration context to be used.
+ * @q : Execution to be used along with migration context.
  * @src_bo: The buffer object @src is currently bound to.
  * @read_write : Creates BB commands for CCS read/write.
  *
@@ -988,7 +990,7 @@ static int emit_flush_invalidate(struct xe_migrate *m, u32 *dw, int i,
  *
  * Return: 0 if successful, negative error code on failure.
  */
-int xe_migrate_ccs_rw_copy(struct xe_migrate *m,
+int xe_migrate_ccs_rw_copy(struct xe_tile *tile, struct xe_exec_queue *q,
                           struct xe_bo *src_bo,
                           enum xe_sriov_vf_ccs_rw_ctxs read_write)
 
@@ -996,7 +998,8 @@ int xe_migrate_ccs_rw_copy(struct xe_migrate *m,
        bool src_is_pltt = read_write == XE_SRIOV_VF_CCS_READ_CTX;
        bool dst_is_pltt = read_write == XE_SRIOV_VF_CCS_WRITE_CTX;
        struct ttm_resource *src = src_bo->ttm.resource;
-       struct xe_gt *gt = m->tile->primary_gt;
+       struct xe_migrate *m = tile->migrate;
+       struct xe_gt *gt = tile->primary_gt;
        u32 batch_size, batch_size_allocated;
        struct xe_device *xe = gt_to_xe(gt);
        struct xe_res_cursor src_it, ccs_it;
@@ -1079,11 +1082,11 @@ int xe_migrate_ccs_rw_copy(struct xe_migrate *m,
 
                emit_pte(m, bb, ccs_pt, false, false, &ccs_it, ccs_size, src);
 
-               bb->len = emit_flush_invalidate(m, bb->cs, bb->len, flush_flags);
+               bb->len = emit_flush_invalidate(q, bb->cs, bb->len, flush_flags);
                flush_flags = xe_migrate_ccs_copy(m, bb, src_L0_ofs, src_is_pltt,
                                                  src_L0_ofs, dst_is_pltt,
                                                  src_L0, ccs_ofs, true);
-               bb->len = emit_flush_invalidate(m, bb->cs, bb->len, flush_flags);
+               bb->len = emit_flush_invalidate(q, bb->cs, bb->len, flush_flags);
 
                size -= src_L0;
        }

diff --git a/drivers/gpu/drm/xe/xe_migrate.h b/drivers/gpu/drm/xe/xe_migrate.h
index a3f3fa281e04f0f0764c67c8d6975e4a9c36e74f..8978d2cc1a75bdaac8d25216db3b5f2c6b39c72e 100644 (file)
--- a/drivers/gpu/drm/xe/xe_migrate.h
+++ b/drivers/gpu/drm/xe/xe_migrate.h
@@ -125,7 +125,7 @@ struct dma_fence *xe_migrate_copy(struct xe_migrate *m,
                                  struct ttm_resource *dst,
                                  bool copy_only_ccs);
 
-int xe_migrate_ccs_rw_copy(struct xe_migrate *m,
+int xe_migrate_ccs_rw_copy(struct xe_tile *tile, struct xe_exec_queue *q,
                           struct xe_bo *src_bo,
                           enum xe_sriov_vf_ccs_rw_ctxs read_write);
 

diff --git a/drivers/gpu/drm/xe/xe_pm.c b/drivers/gpu/drm/xe/xe_pm.c
index ed29791beb7c555a284a17bffeb5301a015f241b..cc489c41ae30774d0f54a8ae3bf88ef9871b9af5 100644 (file)
--- a/drivers/gpu/drm/xe/xe_pm.c
+++ b/drivers/gpu/drm/xe/xe_pm.c
@@ -209,6 +209,9 @@ int xe_pm_resume(struct xe_device *xe)
 
        xe_pxp_pm_resume(xe->pxp);
 
+       if (IS_SRIOV_VF(xe))
+               xe_sriov_vf_ccs_register_context(xe);
+
        drm_dbg(&xe->drm, "Device resumed\n");
        return 0;
 err:

diff --git a/drivers/gpu/drm/xe/xe_sriov_vf_ccs.c b/drivers/gpu/drm/xe/xe_sriov_vf_ccs.c
index f0ca2a9b2bb7b54b5bb754064194e804a7461cba..4872e43eb440c92262ea54a97c52d65e81e1f96f 100644 (file)
--- a/drivers/gpu/drm/xe/xe_sriov_vf_ccs.c
+++ b/drivers/gpu/drm/xe/xe_sriov_vf_ccs.c
@@ -8,6 +8,7 @@
 #include "xe_bb.h"
 #include "xe_bo.h"
 #include "xe_device.h"
+#include "xe_exec_queue.h"
 #include "xe_exec_queue_types.h"
 #include "xe_guc_submit.h"
 #include "xe_lrc.h"
@@ -168,8 +169,8 @@ static int alloc_bb_pool(struct xe_tile *tile, struct xe_tile_vf_ccs *ctx)
 
 static void ccs_rw_update_ring(struct xe_tile_vf_ccs *ctx)
 {
-       struct xe_lrc *lrc = xe_migrate_lrc(ctx->migrate);
        u64 addr = xe_sa_manager_gpu_addr(ctx->mem.ccs_bb_pool);
+       struct xe_lrc *lrc = xe_exec_queue_lrc(ctx->mig_q);
        u32 dw[10], i = 0;
 
        dw[i++] = MI_ARB_ON_OFF | MI_ARB_ENABLE;
@@ -183,13 +184,12 @@ static void ccs_rw_update_ring(struct xe_tile_vf_ccs *ctx)
        xe_lrc_set_ring_tail(lrc, lrc->ring.tail);
 }
 
-static int register_save_restore_context(struct xe_migrate *m,
-                                        enum xe_sriov_vf_ccs_rw_ctxs ctx_id)
+static int register_save_restore_context(struct xe_tile_vf_ccs *ctx)
 {
        int err = -EINVAL;
        int ctx_type;
 
-       switch (ctx_id) {
+       switch (ctx->ctx_id) {
        case XE_SRIOV_VF_CCS_READ_CTX:
                ctx_type = GUC_CONTEXT_COMPRESSION_SAVE;
                break;
@@ -200,7 +200,7 @@ static int register_save_restore_context(struct xe_migrate *m,
                return err;
        }
 
-       xe_guc_register_exec_queue(xe_migrate_exec_queue(m), ctx_type);
+       xe_guc_register_exec_queue(ctx->mig_q, ctx_type);
        return 0;
 }
 
@@ -225,7 +225,7 @@ int xe_sriov_vf_ccs_register_context(struct xe_device *xe)
 
        for_each_ccs_rw_ctx(ctx_id) {
                ctx = &tile->sriov.vf.ccs[ctx_id];
-               err = register_save_restore_context(ctx->migrate, ctx_id);
+               err = register_save_restore_context(ctx);
                if (err)
                        return err;
        }
@@ -236,13 +236,14 @@ int xe_sriov_vf_ccs_register_context(struct xe_device *xe)
 static void xe_sriov_vf_ccs_fini(void *arg)
 {
        struct xe_tile_vf_ccs *ctx = arg;
-       struct xe_lrc *lrc = xe_migrate_lrc(ctx->migrate);
+       struct xe_lrc *lrc = xe_exec_queue_lrc(ctx->mig_q);
 
        /*
         * Make TAIL = HEAD in the ring so that no issues are seen if Guc
         * submits this context to HW on VF pause after unbinding device.
         */
        xe_lrc_set_ring_tail(lrc, xe_lrc_ring_head(lrc));
+       xe_exec_queue_put(ctx->mig_q);
 }
 
 /**
@@ -258,8 +259,9 @@ int xe_sriov_vf_ccs_init(struct xe_device *xe)
 {
        struct xe_tile *tile = xe_device_get_root_tile(xe);
        enum xe_sriov_vf_ccs_rw_ctxs ctx_id;
-       struct xe_migrate *migrate;
        struct xe_tile_vf_ccs *ctx;
+       struct xe_exec_queue *q;
+       u32 flags;
        int err;
 
        xe_assert(xe, IS_SRIOV_VF(xe));
@@ -270,37 +272,40 @@ int xe_sriov_vf_ccs_init(struct xe_device *xe)
                ctx = &tile->sriov.vf.ccs[ctx_id];
                ctx->ctx_id = ctx_id;
 
-               migrate = xe_migrate_alloc(tile);
-               if (!migrate) {
-                       err = -ENOMEM;
+               flags = EXEC_QUEUE_FLAG_KERNEL |
+                       EXEC_QUEUE_FLAG_PERMANENT |
+                       EXEC_QUEUE_FLAG_MIGRATE;
+               q = xe_exec_queue_create_bind(xe, tile, flags, 0);
+               if (IS_ERR(q)) {
+                       err = PTR_ERR(q);
                        goto err_ret;
                }
-
-               err = xe_migrate_init(migrate);
-               if (err)
-                       goto err_ret;
-
-               ctx->migrate = migrate;
+               ctx->mig_q = q;
 
                err = alloc_bb_pool(tile, ctx);
                if (err)
-                       goto err_ret;
+                       goto err_free_queue;
 
                ccs_rw_update_ring(ctx);
 
-               err = register_save_restore_context(ctx->migrate, ctx_id);
+               err = register_save_restore_context(ctx);
                if (err)
-                       goto err_ret;
+                       goto err_free_queue;
 
                err = devm_add_action_or_reset(xe->drm.dev,
                                               xe_sriov_vf_ccs_fini,
                                               ctx);
+               if (err)
+                       goto err_ret;
        }
 
        xe->sriov.vf.ccs.initialized = 1;
 
        return 0;
 
+err_free_queue:
+       xe_exec_queue_put(q);
+
 err_ret:
        return err;
 }
@@ -319,7 +324,7 @@ int xe_sriov_vf_ccs_attach_bo(struct xe_bo *bo)
 {
        struct xe_device *xe = xe_bo_device(bo);
        enum xe_sriov_vf_ccs_rw_ctxs ctx_id;
-       struct xe_migrate *migrate;
+       struct xe_tile_vf_ccs *ctx;
        struct xe_tile *tile;
        struct xe_bb *bb;
        int err = 0;
@@ -334,8 +339,8 @@ int xe_sriov_vf_ccs_attach_bo(struct xe_bo *bo)
                /* bb should be NULL here. Assert if not NULL */
                xe_assert(xe, !bb);
 
-               migrate = tile->sriov.vf.ccs[ctx_id].migrate;
-               err = xe_migrate_ccs_rw_copy(migrate, bo, ctx_id);
+               ctx = &tile->sriov.vf.ccs[ctx_id];
+               err = xe_migrate_ccs_rw_copy(tile, ctx->mig_q, bo, ctx_id);
        }
        return err;
 }

diff --git a/drivers/gpu/drm/xe/xe_sriov_vf_ccs_types.h b/drivers/gpu/drm/xe/xe_sriov_vf_ccs_types.h
index e240f3fd18af1cf158665c108cc4701e8a2f304f..93435a6f4cb6123bb9c3da2799f7fc04dbc9fd9a 100644 (file)
--- a/drivers/gpu/drm/xe/xe_sriov_vf_ccs_types.h
+++ b/drivers/gpu/drm/xe/xe_sriov_vf_ccs_types.h
@@ -41,11 +41,11 @@ struct xe_sa_manager;
 struct xe_tile_vf_ccs {
        /** @id: Id to which context it belongs to */
        enum xe_sriov_vf_ccs_rw_ctxs ctx_id;
-       /** @migrate: Migration helper for save/restore of CCS data */
-       struct xe_migrate *migrate;
+       /** @mig_q: exec queues used for migration */
+       struct xe_exec_queue *mig_q;
 
        struct {
-               /** @ccs_rw_bb_pool: Pool from which batch buffers are allocated. */
+               /** @ccs_bb_pool: Pool from which batch buffers are allocated. */
                struct xe_sa_manager *ccs_bb_pool;
        } mem;
 };