[PATCH v4 2/2] drm/xe/bo: add GPU memory trace points

[Lucas De Marchi]

On Fri, Jun 13, 2025 at 09:02:27AM +0100, Tvrtko Ursulin wrote:
>
>On 12/06/2025 19:53, Yiwei Zhang wrote:
>>On Thu, Jun 12, 2025 at 11:02 AM Lucas De Marchi
>><lucas.demarchi at intel.com> wrote:
>>>
>>>On Thu, Jun 12, 2025 at 05:46:52PM +0100, Tvrtko Ursulin wrote:
>>>>
>>>>On 12/06/2025 06:40, Lucas De Marchi wrote:
>>>>>On Wed, Jun 11, 2025 at 03:51:24PM -0700, Juston Li wrote:
>>>>>>Add TRACE_GPU_MEM tracepoints for tracking global and per-process GPU
>>>>>>memory usage.
>>>>>>
>>>>>>These are required by VSR on Android 12+ for reporting GPU driver memory
>>>>>>allocations.
>>>>>>
>>>>>>v3:
>>>>>>- Use now configurable CONFIG_TRACE_GPU_MEM instead of adding a
>>>>>>  per-driver Kconfig (Lucas)
>>>>>>
>>>>>>v2:
>>>>>>- Use u64 as preferred by checkpatch (Tvrtko)
>>>>>>- Fix errors in comments/Kconfig description (Tvrtko)
>>>>>>- drop redundant "CONFIG" in Kconfig
>>>>>>
>>>>>>Signed-off-by: Juston Li <justonli at chromium.org>
>>>>>>Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin at igalia.com>
>>>>>>---
>>>>>>drivers/gpu/drm/xe/xe_bo.c           | 47 ++++++++++++++++++++++++++++
>>>>>>drivers/gpu/drm/xe/xe_device_types.h | 16 ++++++++++
>>>>>>2 files changed, 63 insertions(+)
>>>>>>
>>>>>>diff --git a/drivers/gpu/drm/xe/xe_bo.c b/drivers/gpu/drm/xe/xe_bo.c
>>>>>>index 4e39188a021ab..89a3d23e3b800 100644
>>>>>>--- a/drivers/gpu/drm/xe/xe_bo.c
>>>>>>+++ b/drivers/gpu/drm/xe/xe_bo.c
>>>>>>@@ -19,6 +19,8 @@
>>>>>>
>>>>>>#include <kunit/static_stub.h>
>>>>>>
>>>>>>+#include <trace/events/gpu_mem.h>
>>>>>>+
>>>>>>#include "xe_device.h"
>>>>>>#include "xe_dma_buf.h"
>>>>>>#include "xe_drm_client.h"
>>>>>>@@ -418,6 +420,35 @@ static void xe_ttm_tt_account_subtract(struct
>>>>>>xe_device *xe, struct ttm_tt *tt)
>>>>>>        xe_shrinker_mod_pages(xe->mem.shrinker, -(long)tt->num_pages, 0);
>>>>>>}
>>>>>>
>>>>>>+#if IS_ENABLED(CONFIG_TRACE_GPU_MEM)
>>>>>>+static void update_global_total_pages(struct ttm_device *ttm_dev,
>>>>>>long num_pages)
>>>>>>+{
>>>>>>+    struct xe_device *xe = ttm_to_xe_device(ttm_dev);
>>>>>>+    u64 global_total_pages =
>>>>>>+        atomic64_add_return(num_pages, &xe->global_total_pages);
>>>>>>+
>>>>>>+    trace_gpu_mem_total(0, 0, global_total_pages << PAGE_SHIFT);
>>>>>>+}
>>>>>>+
>>>>>>+static void update_process_mem(struct drm_file *file, ssize_t size)
>>>>>>+{
>>>>>>+    struct xe_file *xef = to_xe_file(file);
>>>>>>+    u64 process_mem = atomic64_add_return(size, &xef->process_mem);
>>>>>>+
>>>>>>+    rcu_read_lock(); /* Locks file->pid! */
>>>>>>+    trace_gpu_mem_total(0, pid_nr(rcu_dereference(file->pid)),
>>>>>>process_mem);
>>>>>
>>>>>Isn't the first arg supposed to be the gpu id? Doesn't this become
>>>>>invalid when I have e.g. LNL + BMG and the trace is enabled?
>>>>
>>>>Good point.
>>>>
>>>>u32 gpu_id does not seem possible to map to anything useful.
>>>
>>>maybe minor_id? although I'm not sure if the intention is to share this
>>>outside drm as seems the case.
>>
>>Yes, that was for render minor in the case of drm.
>
>Or to keep the field as integer we can use dev->primary->index, which 
>would then correlate with the /sys/class/drm/card%u, in case it needs 
>to be mapped back.
>
>There is prior art in various drivers to use either dev_name or 
>dev->primary->index, but for this one it is probably easier to stick 
>with the integer so both msm can keep passing the zero and we don't 

both msm?  In xe we'd use dev->primary->index, right?

Lucas De Marchi

>have to think about Android userspace forward/backward compatibility.
>
>Regards,
>
>Tvrtko
>
>>
>>>
>>>>
>>>>Shall we replace it with a string obtained from dev_name(struct device
>>>>*) ? As only Android parses them I think we can get still away with
>>>>changing the tracepoints ABI.
>>>
>>>works for me too. Is Android actually parsing it or just ignoring?
>>>Because afaics it's always 0 in msm.
>>
>>Android has used it as part of the bpf map key:
>>https://cs.android.com/android/platform/superproject/main/+/main:frameworks/native/services/gpuservice/bpfprogs/gpuMem.c
>>
>>>
>>>Lucas De Marchi
>