Re: [PATCH v2 3/7] drm/amdgpu: Add new function to put GPU power profile
From: Shashank Sharma
Date: Mon Aug 21 2023 - 09:40:08 EST
On 21/08/2023 08:47, Arvind Yadav wrote:
This patch adds a function which will clear the GPU
power profile after job finished.
This is how it works:
- schedular will set the GPU power profile based on ring_type.
- Schedular will clear the GPU Power profile once job finished.
- Here, the *_workload_profile_set function will set the GPU
power profile and the *_workload_profile_put function will
schedule the smu_delayed_work task after 100ms delay. This
smu_delayed_work task will clear a GPU power profile if any
new jobs are not scheduled within 100 ms. But if any new job
comes within 100ms then the *_workload_profile_set function
will cancel this work and set the GPU power profile based on
preferences.
v2:
- Splitting workload_profile_set and workload_profile_put
into two separate patches.
- Addressed review comment.
Cc: Shashank Sharma <shashank.sharma@xxxxxxx>
Cc: Christian Koenig <christian.koenig@xxxxxxx>
Cc: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Arvind Yadav <Arvind.Yadav@xxxxxxx>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_workload.c | 97 +++++++++++++++++++
drivers/gpu/drm/amd/include/amdgpu_workload.h | 3 +
2 files changed, 100 insertions(+)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_workload.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_workload.c
index e661cc5b3d92..6367eb88a44d 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_workload.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_workload.c
@@ -24,6 +24,9 @@
#include "amdgpu.h"
+/* 100 millsecond timeout */
+#define SMU_IDLE_TIMEOUT msecs_to_jiffies(100)
+
static enum PP_SMC_POWER_PROFILE
ring_to_power_profile(uint32_t ring_type)
{
@@ -59,6 +62,80 @@ amdgpu_power_profile_set(struct amdgpu_device *adev,
return ret;
}
+static int
+amdgpu_power_profile_clear(struct amdgpu_device *adev,
+ enum PP_SMC_POWER_PROFILE profile)
+{
+ int ret = amdgpu_dpm_switch_power_profile(adev, profile, false);
+
+ if (!ret) {
+ /* Clear the bit for the submitted workload profile */
+ adev->smu_workload.submit_workload_status &= ~(1 << profile);
+ }
+
+ return ret;
+}
+
+static void
+amdgpu_power_profile_idle_work_handler(struct work_struct *work)
+{
+
+ struct amdgpu_smu_workload *workload = container_of(work,
+ struct amdgpu_smu_workload,
+ smu_delayed_work.work);
+ struct amdgpu_device *adev = workload->adev;
+ bool reschedule = false;
+ int index = fls(workload->submit_workload_status);
+ int ret;
+
We should check validity and range of index here before before using it
below.
+ mutex_lock(&workload->workload_lock);
+ for (; index > 0; index--) {
+ int val = atomic_read(&workload->power_profile_ref[index]);
+
+ if (val) {
+ reschedule = true;
+ } else {
+ if (workload->submit_workload_status &
+ (1 << index)) {
+ ret = amdgpu_power_profile_clear(adev, index);
+ if (ret) {
+ DRM_WARN("Failed to clear workload %s,error = %d\n",
+ amdgpu_workload_mode_name[index], ret);
+ goto exit;
instead of exiting, we might wanna continue the loop here, just to check
if we are able to reset another profile in the next attempt.
+ }
+ }
+ }
+ }
A blank line recommended here.
+ if (reschedule)
+ schedule_delayed_work(&workload->smu_delayed_work,
+ SMU_IDLE_TIMEOUT);
+exit:
+ mutex_unlock(&workload->workload_lock);
+}
+
+void amdgpu_workload_profile_put(struct amdgpu_device *adev,
+ uint32_t ring_type)
+{
+ struct amdgpu_smu_workload *workload = &adev->smu_workload;
+ enum PP_SMC_POWER_PROFILE profile = ring_to_power_profile(ring_type);
+
+ if (profile == PP_SMC_POWER_PROFILE_BOOTUP_DEFAULT)
+ return;
+
+ mutex_lock(&workload->workload_lock);
+
+ if (!atomic_read(&workload->power_profile_ref[profile])) {
+ DRM_WARN("Power profile %s ref. count error\n",
+ amdgpu_workload_mode_name[profile]);
+ } else {
+ atomic_dec(&workload->power_profile_ref[profile]);
+ schedule_delayed_work(&workload->smu_delayed_work,
+ SMU_IDLE_TIMEOUT);
We don't want to schedule this work everytime a power profile is put,
but we want to do that only when a power profile ref count reaches '0'.
So you might want to check the ref_count, and schedule the work under a
if (!ref_count) condition.
+ }
+
+ mutex_unlock(&workload->workload_lock);
+}
+
void amdgpu_workload_profile_set(struct amdgpu_device *adev,
uint32_t ring_type)
{
@@ -70,13 +147,30 @@ void amdgpu_workload_profile_set(struct amdgpu_device *adev,
return;
mutex_lock(&workload->workload_lock);
+ cancel_delayed_work_sync(&workload->smu_delayed_work);
ret = amdgpu_power_profile_set(adev, profile);
if (ret) {
DRM_WARN("Failed to set workload profile to %s, error = %d\n",
amdgpu_workload_mode_name[profile], ret);
+ goto exit;
+ }
+
+ /* Clear the already finished jobs of higher power profile*/
We are not clearing the jobs here, but their power profiles.
I would recommend a little rework in the comment like "As we cancelled
the delayed work, check and clear the pending higher power profiles set
by previous jobs which are done now"
+ for (int index = fls(workload->submit_workload_status);
The index can be initialized above, like the put function for loop.
+ index > profile; index--) {
+ if (!atomic_read(&workload->power_profile_ref[index]) &&
+ workload->submit_workload_status & (1 << index)) {
+ ret = amdgpu_power_profile_clear(adev, index);
After clearing the power profile, we should also clear the respective
workload->submit_workload_status bit as well, right ?
+ if (ret) {
+ DRM_WARN("Failed to clear workload %s, err = %d\n",
+ amdgpu_workload_mode_name[profile], ret);
+ goto exit;
Same as previous about continuing the loop.
- Shashank
+ }
+ }
}
+exit:
mutex_unlock(&workload->workload_lock);
}
@@ -87,6 +181,8 @@ void amdgpu_workload_profile_init(struct amdgpu_device *adev)
adev->smu_workload.initialized = true;
mutex_init(&adev->smu_workload.workload_lock);
+ INIT_DELAYED_WORK(&adev->smu_workload.smu_delayed_work,
+ amdgpu_power_profile_idle_work_handler);
}
void amdgpu_workload_profile_fini(struct amdgpu_device *adev)
@@ -94,6 +190,7 @@ void amdgpu_workload_profile_fini(struct amdgpu_device *adev)
if (!adev->smu_workload.initialized)
return;
+ cancel_delayed_work_sync(&adev->smu_workload.smu_delayed_work);
adev->smu_workload.submit_workload_status = 0;
adev->smu_workload.initialized = false;
mutex_destroy(&adev->smu_workload.workload_lock);
diff --git a/drivers/gpu/drm/amd/include/amdgpu_workload.h b/drivers/gpu/drm/amd/include/amdgpu_workload.h
index 5022f28fc2f9..ee1f87257f2d 100644
--- a/drivers/gpu/drm/amd/include/amdgpu_workload.h
+++ b/drivers/gpu/drm/amd/include/amdgpu_workload.h
@@ -46,6 +46,9 @@ static const char * const amdgpu_workload_mode_name[] = {
"Window3D"
};
+void amdgpu_workload_profile_put(struct amdgpu_device *adev,
+ uint32_t ring_type);
+
void amdgpu_workload_profile_set(struct amdgpu_device *adev,
uint32_t ring_type);