[Intel-gfx] [PATCH 5/7] drm/i915/guc: Use streaming loads to speed up dumping the guc log

John.C.Harrison
2022-07-28T02:21:31Z

From: Chris Wilson <chris.p.wilson@intel.com>

Use a temporary page and mempy_from_wc to reduce the time it takes to
dump the guc log to debugfs.

Signed-off-by: Chris Wilson <chris.p.wilson@intel.com>
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Reviewed-by: John Harrison <John.C.Harrison@Intel.com>
---
drivers/gpu/drm/i915/gt/uc/intel_guc_log.c | 24 ++++++++++++++++------
1 file changed, 18 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_log.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_log.c
index 07d31ae32f765..4722d4b18ed19 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_guc_log.c
+++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_log.c
@@ -750,8 +750,9 @@ int intel_guc_log_dump(struct intel_guc_log *log, struct drm_printer *p,
struct intel_guc *guc = log_to_guc(log);
struct intel_uc *uc = container_of(guc, struct intel_uc, guc);
struct drm_i915_gem_object *obj = NULL;
- u32 *map;
- int i = 0;
+ void *map;
+ u32 *page;
+ int i, j;

if (!intel_guc_is_supported(guc))
return -ENODEV;
@@ -764,23 +765,34 @@ int intel_guc_log_dump(struct intel_guc_log *log, struct drm_printer *p,
if (!obj)
return 0;

+ page = (u32 *)__get_free_page(GFP_KERNEL);
+ if (!page)
+ return -ENOMEM;
+
intel_guc_dump_time_info(guc, p);

map = i915_gem_object_pin_map_unlocked(obj, I915_MAP_WC);
if (IS_ERR(map)) {
DRM_DEBUG("Failed to pin object\n");
drm_puts(p, "(log data unaccessible)\n");
+ free_page((unsigned long)page);
return PTR_ERR(map);
}

- for (i = 0; i < obj->base.size / sizeof(u32); i += 4)
- drm_printf(p, "0x%08x 0x%08x 0x%08x 0x%08x\n",
- *(map + i), *(map + i + 1),
- *(map + i + 2), *(map + i + 3));
+ for (i = 0; i < obj->base.size; i += PAGE_SIZE) {
+ if (!i915_memcpy_from_wc(page, map + i, PAGE_SIZE))
+ memcpy(page, map + i, PAGE_SIZE);
+
+ for (j = 0; j < PAGE_SIZE / sizeof(u32); j += 4)
+ drm_printf(p, "0x%08x 0x%08x 0x%08x 0x%08x\n",
+ *(page + j + 0), *(page + j + 1),
+ *(page + j + 2), *(page + j + 3));
+ }

drm_puts(p, "\n");

i915_gem_object_unpin_map(obj);
+ free_page((unsigned long)page);

return 0;
}
--
2.37.1