Predict an optimal delay to enable GFXOFF for the next interval
based on the request count:
- less than 15 requests per second - zero delay
- less than 25 requests per second - default delay
- 25 and more requests per second - don't enable GFXOFF
The algorithm allows maintaining low power consumption in idle,
as well as using the full GPU power under load by eliminating
hundreds of extra GFXOFF ON/OFF switches.
Test configuration:
- Ryzen 5 2500U
- Ryzen 5 3400G
- Chromium 134.0.6998.88 Arch Linux
- Mesa 1:24.3.4-1
- KDE Plasma 6.3.2
GFXOFF enable requests per second:
| Test | min | max |
|-----------------------------------------------------|-----|-----|
| System idle | 0 | 64 |
| Web browsing | 0 | 127 |
| WebGL aquarium | 10 | 236 |
| Heavy load: glxgears + vkcube + resizing + flipping | 39 | 677 |
Test results, Ryzen 5 2500U:
| Test | patched-6.13.7.arch1 | 6.13.7.arch1-1 |
|-----------------------------|----------------------|------------------|
| System idle (PkgWatt) | ~0.74W | ~1.25W |
| glxgears (vblank_mode=0) | ~7300 fps, ~7.3W | ~7300 fps, ~7.3W |
| WebGL aquarium 15.000 fish | 56-60 fps, ~9.8W | 55-60 fps, ~9.8W |
Test results, Ryzen 5 3400G:
| Test | patched-6.13.7.arch1 | 6.13.7.arch1-1 |
|-----------------------------|----------------------|------------------|
| System idle (PkgWatt) | ~3.8W | ~4.3W |
| glxgears (vblank_mode=0) | ~7200 fps | ~7200 fps |
| WebGL aquarium 30.000 fish | 37 fps, 47W | 38 fps, 47W |
Signed-off-by: Sergey Kovalenko <seryoga.engineer...@gmail.com>
Tested-by: Liam Fleming <fleming.squa...@proton.me>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_gfx.c | 94 +++++++++++++++++--------
drivers/gpu/drm/amd/amdgpu/amdgpu_gfx.h | 3 +
2 files changed, 67 insertions(+), 30 deletions(-)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_gfx.c
b/drivers/gpu/drm/amd/amdgpu/amdgpu_gfx.c
index c1f35ded684e..5e23b956e0bf 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_gfx.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_gfx.c
@@ -781,55 +781,89 @@ int amdgpu_gfx_enable_kgq(struct amdgpu_device
*adev, int xcc_id)
* 3. other client can cancel their request of disable gfx off feature
* 4. other client should not send request to enable gfx off feature
before disable gfx off feature.
*/
-
void amdgpu_gfx_off_ctrl(struct amdgpu_device *adev, bool enable)
{
- unsigned long delay = GFX_OFF_DELAY_ENABLE;
-
if (!(adev->pm.pp_feature & PP_GFXOFF_MASK))
return;
mutex_lock(&adev->gfx.gfx_off_mutex);
if (enable) {
- /* If the count is already 0, it means there's an imbalance bug
somewhere.
- * Note that the bug may be in a different caller than the one which
triggers the
- * WARN_ON_ONCE.
- */
- if (WARN_ON_ONCE(adev->gfx.gfx_off_req_count == 0))
+ /* This case covers multiple calls from parallel threads */
+ if (!adev->gfx.gfx_off_req_count)
goto unlock;
- adev->gfx.gfx_off_req_count--;
+ /* Process only if req_count == 0 and GFXOFF is disabled */
+ if (--adev->gfx.gfx_off_req_count || adev->gfx.gfx_off_state)
+ goto unlock;
+
+ /* If going to s2idle, no need to wait */
+ if (adev->in_s0ix) {
+ if (!amdgpu_dpm_set_powergating_by_smu(
+ adev, AMD_IP_BLOCK_TYPE_GFX, true, 0))
+ adev->gfx.gfx_off_state = true;
+
+ /* Reset delay flag */
+ adev->gfx.gfx_off_use_delay = 0;
+ goto unlock;
+ }
- if (adev->gfx.gfx_off_req_count == 0 &&
- !adev->gfx.gfx_off_state) {
- /* If going to s2idle, no need to wait */
- if (adev->in_s0ix) {
- if (!amdgpu_dpm_set_powergating_by_smu(adev,
- AMD_IP_BLOCK_TYPE_GFX, true, 0))
- adev->gfx.gfx_off_state = true;
+ ++adev->gfx.gfx_off_counter;
+
+ uint64_t now = get_jiffies_64();
+ uint64_t delta =
+ jiffies_to_msecs(now - adev->gfx.gfx_off_timestamp);
+
+ if (delta >= 1000u) {
+ /*
+ * Predict the optimal delay for the next interval
+ * based on the current number of requests:
+ * <15 - idle, no delay
+ * <25 - light/medium load, default delay
+ * 25 and more - high load, GFXOFF disabled
+ */
+ if (adev->gfx.gfx_off_counter < 15u) {
+ adev->gfx.gfx_off_use_delay = 0;
+ } else if (adev->gfx.gfx_off_counter < 25u) {
+ adev->gfx.gfx_off_use_delay = 1;
} else {
-
schedule_delayed_work(&adev->gfx.gfx_off_delay_work,
- delay);
+ adev->gfx.gfx_off_use_delay = 2;
}
+
+ adev->gfx.gfx_off_counter = 0;
+ adev->gfx.gfx_off_timestamp = now;
}
+
+ /* Don't schedule gfxoff under heavy load */
+ if (adev->gfx.gfx_off_use_delay == 2)
+ goto unlock;
+
+ schedule_delayed_work(&adev->gfx.gfx_off_delay_work,
+ adev->gfx.gfx_off_use_delay ?
+ GFX_OFF_DELAY_ENABLE :
+ GFX_OFF_NO_DELAY);
} else {
- if (adev->gfx.gfx_off_req_count == 0) {
- cancel_delayed_work_sync(&adev->gfx.gfx_off_delay_work);
+ /* GFXOFF was enabled when req_count == 0 */
+ if (++adev->gfx.gfx_off_req_count != 1)
+ goto unlock;
- if (adev->gfx.gfx_off_state &&
- !amdgpu_dpm_set_powergating_by_smu(adev, AMD_IP_BLOCK_TYPE_GFX,
false, 0)) {
- adev->gfx.gfx_off_state = false;
+ /* Nothing to do if the work wasn't scheduled */
+ if (adev->gfx.gfx_off_use_delay == 2)
+ goto unlock;
- if (adev->gfx.funcs->init_spm_golden) {
- dev_dbg(adev->dev,
- "GFXOFF is disabled, re-init SPM
golden settings\n");
- amdgpu_gfx_init_spm_golden(adev);
- }
+ cancel_delayed_work_sync(&adev->gfx.gfx_off_delay_work);
+
+ if (adev->gfx.gfx_off_state &&
+ !amdgpu_dpm_set_powergating_by_smu(
+ adev, AMD_IP_BLOCK_TYPE_GFX, false, 0)) {
+ adev->gfx.gfx_off_state = false;
+
+ if (adev->gfx.funcs->init_spm_golden) {
+ dev_dbg(adev->dev,
+ "GFXOFF is disabled, re-init SPM golden
settings\n");
+ amdgpu_gfx_init_spm_golden(adev);
}
}
-
- adev->gfx.gfx_off_req_count++;
}
unlock:
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_gfx.h
b/drivers/gpu/drm/amd/amdgpu/amdgpu_gfx.h
index 8b5bd63b5773..38fd445a353b 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_gfx.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_gfx.h
@@ -430,7 +430,10 @@ struct amdgpu_gfx {
/* gfx off */
bool gfx_off_state; /* true: enabled,
false: disabled */
struct mutex gfx_off_mutex; /* mutex to
change gfxoff state */
+ uint64_t gfx_off_timestamp; /* gfxoff enable
call timestamp */
+ uint32_t gfx_off_use_delay; /* flag to choose
the delay range */
uint32_t gfx_off_req_count; /* default 1,
enable gfx off: dec 1, disable gfx off: add 1 */
+ uint32_t gfx_off_counter; /* count of gfxoff
enable calls */
struct delayed_work gfx_off_delay_work; /* async work to
set gfx block off */
uint32_t gfx_off_residency; /* last logged
residency */
uint64_t gfx_off_entrycount; /* count of times
GPU has get into GFXOFF state */
--
2.49.0
