On 6/24/2024 3:08 PM, Christian König wrote:
> Am 24.06.24 um 08:34 schrieb Lazar, Lijo:
>>
>> On 6/24/2024 12:01 PM, Vignesh Chander wrote:
>>> correctly handle the case when trylock fails when gpu is
>>> about to be reset by dropping the request instead of using mmio
>>>
>>> Signed-off-by: Vignesh Chander <Vignesh.Chander@xxxxxxx>
>> Reviewed-by: Lijo Lazar <lijo.lazar@xxxxxxx>
>>
>> Thanks,
>> Lijo
>>
>>> ---
>>> drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 38 ++++++++++++----------
>>> 1 file changed, 21 insertions(+), 17 deletions(-)
>>>
>>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
>>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
>>> index a7ce8280b17ce7..3cfd24699d691d 100644
>>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
>>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
>>> @@ -613,10 +613,11 @@ uint32_t amdgpu_device_rreg(struct
>>> amdgpu_device *adev,
>>> if ((reg * 4) < adev->rmmio_size) {
>>> if (!(acc_flags & AMDGPU_REGS_NO_KIQ) &&
>>> - amdgpu_sriov_runtime(adev) &&
>>> - down_read_trylock(&adev->reset_domain->sem)) {
>>> - ret = amdgpu_kiq_rreg(adev, reg, 0);
>>> - up_read(&adev->reset_domain->sem);
>>> + amdgpu_sriov_runtime(adev) {
>>> + if (down_read_trylock(&adev->reset_domain->sem)) {
>>> + ret = amdgpu_kiq_rreg(adev, reg, 0);
>>> + up_read(&adev->reset_domain->sem);
>>> + }
>
> What has actually changed here? As far as I can see that isn't
> functionally different to the existing code.
>
In earlier logic, if it fails to get the lock, it takes the 'else' path.
The 'else' path is not meant for sriov/vf.
Thanks,
Lijo
> Regards,
> Christian.
>
>>> } else {
>>> ret = readl(((void __iomem *)adev->rmmio) + (reg * 4));
>>> }
>>> @@ -681,10 +682,11 @@ uint32_t amdgpu_device_xcc_rreg(struct
>>> amdgpu_device *adev,
>>> &rlcg_flag)) {
>>> ret = amdgpu_virt_rlcg_reg_rw(adev, reg, 0, rlcg_flag,
>>> GET_INST(GC, xcc_id));
>>> } else if (!(acc_flags & AMDGPU_REGS_NO_KIQ) &&
>>> - amdgpu_sriov_runtime(adev) &&
>>> - down_read_trylock(&adev->reset_domain->sem)) {
>>> - ret = amdgpu_kiq_rreg(adev, reg, xcc_id);
>>> - up_read(&adev->reset_domain->sem);
>>> + amdgpu_sriov_runtime(adev) {
>>> + if (down_read_trylock(&adev->reset_domain->sem)) {
>>> + ret = amdgpu_kiq_rreg(adev, reg, xcc_id);
>>> + up_read(&adev->reset_domain->sem);
>>> + }
>>> } else {
>>> ret = readl(((void __iomem *)adev->rmmio) + (reg * 4));
>>> }
>>> @@ -740,10 +742,11 @@ void amdgpu_device_wreg(struct amdgpu_device
>>> *adev,
>>> if ((reg * 4) < adev->rmmio_size) {
>>> if (!(acc_flags & AMDGPU_REGS_NO_KIQ) &&
>>> - amdgpu_sriov_runtime(adev) &&
>>> - down_read_trylock(&adev->reset_domain->sem)) {
>>> - amdgpu_kiq_wreg(adev, reg, v, 0);
>>> - up_read(&adev->reset_domain->sem);
>>> + amdgpu_sriov_runtime(adev) {
>>> + if (down_read_trylock(&adev->reset_domain->sem)) {
>>> + amdgpu_kiq_wreg(adev, reg, v, 0);
>>> + up_read(&adev->reset_domain->sem);
>>> + }
>>> } else {
>>> writel(v, ((void __iomem *)adev->rmmio) + (reg * 4));
>>> }
>>> @@ -812,11 +815,12 @@ void amdgpu_device_xcc_wreg(struct
>>> amdgpu_device *adev,
>>> &rlcg_flag)) {
>>> amdgpu_virt_rlcg_reg_rw(adev, reg, v, rlcg_flag,
>>> GET_INST(GC, xcc_id));
>>> } else if (!(acc_flags & AMDGPU_REGS_NO_KIQ) &&
>>> - amdgpu_sriov_runtime(adev) &&
>>> - down_read_trylock(&adev->reset_domain->sem)) {
>>> - amdgpu_kiq_wreg(adev, reg, v, xcc_id);
>>> - up_read(&adev->reset_domain->sem);
>>> - } else {
>>> + amdgpu_sriov_runtime(adev) {
>>> + if (down_read_trylock(&adev->reset_domain->sem)) {
>>> + amdgpu_kiq_wreg(adev, reg, v, xcc_id);
>>> + up_read(&adev->reset_domain->sem);
>>> + }
>>> + } else {
>>> writel(v, ((void __iomem *)adev->rmmio) + (reg * 4));
>>> }
>>> } else {
>
