drm/xe: Add cpu_caching to properties line in VM snapshot capture

Add CPU caching to properties line in VM snapshot capture indicating
the BO caching properites. This is useful information for debug and
will help build a robust GPU hang replay tool.

The current format is:

[<vma address>]: <permissions>|<type>|mem_region=0x%x|pat_index=%d|cpu_caching=%d

Permissions has two options, either "read_only" or "read_write".

Type has three options, either "userptr", "null_sparse", or "bo".

Memory region is a bit mask of where the memory is located.

Pat index corresponds to the value setup upon VM bind.

CPU caching corresponds to the value of BO setup upon creation.

v2:
 - Save off cpu_caching value rather than looking at BO (Carlos)
v4:
 - Fix NULL ptr dereference (Carlos)

Cc: José Roberto de Souza <jose.souza@intel.com>
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Jonathan Cavitt <jonathan.cavitt@intel.com>
Link: https://patch.msgid.link/20251126185952.546277-6-matthew.brost@intel.com

diff --git a/drivers/gpu/drm/xe/xe_vm.c b/drivers/gpu/drm/xe/xe_vm.c
index b298953d2eed61d272b95af01fa911fbd2ace767..8bf3f9d3d644b06ef9dc006b29ce7cffa90ca8e1 100644 (file)
--- a/drivers/gpu/drm/xe/xe_vm.c
+++ b/drivers/gpu/drm/xe/xe_vm.c
@@ -4053,6 +4053,7 @@ struct xe_vm_snapshot {
                unsigned long flags;
                int uapi_mem_region;
                int pat_index;
+               int cpu_caching;
                struct xe_bo *bo;
                void *data;
                struct mm_struct *mm;
@@ -4097,6 +4098,7 @@ struct xe_vm_snapshot *xe_vm_snapshot_capture(struct xe_vm *vm)
                        XE_VM_SNAP_FLAG_READ_ONLY : 0;
                snap->snap[i].pat_index = vma->attr.pat_index;
                if (bo) {
+                       snap->snap[i].cpu_caching = bo->cpu_caching;
                        snap->snap[i].bo = xe_bo_get(bo);
                        snap->snap[i].bo_ofs = xe_vma_bo_offset(vma);
                        switch (bo->ttm.resource->mem_type) {
@@ -4197,7 +4199,7 @@ void xe_vm_snapshot_print(struct xe_vm_snapshot *snap, struct drm_printer *p)
        for (i = 0; i < snap->num_snaps; i++) {
                drm_printf(p, "[%llx].length: 0x%lx\n", snap->snap[i].ofs, snap->snap[i].len);
 
-               drm_printf(p, "[%llx].properties: %s|%s|mem_region=0x%lx|pat_index=%d\n",
+               drm_printf(p, "[%llx].properties: %s|%s|mem_region=0x%lx|pat_index=%d|cpu_caching=%d\n",
                           snap->snap[i].ofs,
                           snap->snap[i].flags & XE_VM_SNAP_FLAG_READ_ONLY ?
                           "read_only" : "read_write",
@@ -4207,7 +4209,8 @@ void xe_vm_snapshot_print(struct xe_vm_snapshot *snap, struct drm_printer *p)
                           "userptr" : "bo",
                           snap->snap[i].uapi_mem_region == -1 ? 0 :
                           BIT(snap->snap[i].uapi_mem_region),
-                          snap->snap[i].pat_index);
+                          snap->snap[i].pat_index,
+                          snap->snap[i].cpu_caching);
 
                if (IS_ERR(snap->snap[i].data)) {
                        drm_printf(p, "[%llx].error: %li\n", snap->snap[i].ofs,