Hi Paul,
Answers as below:
-----Original Message-----
From: Paul Menzel <pmenzel+amd-gfx@xxxxxxxxxxxxx>
Sent: Wednesday, August 8, 2018 10:29 PM
To: Deng, Emily <Emily.Deng at amd.com>; amd-gfx at lists.freedesktop.org
Cc: Liu, Monk <Monk.Liu at amd.com>
Subject: Re: [PATCH] drm/amdgpu/sriov: give 8s for recover vram under RUNTIME
Dear Deng,
On 08/08/18 04:13, Emily Deng wrote:
> Modify the commit message
I guess the line above is a leftover from some template, and can be
removed?
[Emily] It is removed
> Extend the timeout for recovering vram bos from shadows on sr-iov
> to cover the worst case scenario for timeslices and VFs
>
> Under runtime, the wait fence time could be quite long when
> other VFs are in exclusive mode. For example, for 4 VF, every
> VF's exclusive timeout time is set to 3s, then the worst case is
> 9s. If the VF number is more than 4,then the worst case time will
> be longer.
Nit: Missing space after the comma.
How did you get to nine seconds? Isnâ??t it four times three, which is
twelve?
[Emily] It is 3 times three, not 4, as the VF only need to wait the other three VF's exclusive timeout.
> The 8s is the test data, with setting to 8s, it will pass the TDR
> test for 1000 times.
>
> SWDEV-161490
>
> Change-Id: Ifc32d56ca7fde01b1f4fe2b0db6959b51909008a
> Signed-off-by: Monk Liu <Monk.Liu at amd.com>
> Signed-off-by: Emily Deng <Emily.Deng at amd.com>
> ---
> drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> index 1d933db..ef82ad1 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> @@ -3124,7 +3124,7 @@ static int amdgpu_device_handle_vram_lost(struct amdgpu_device *adev)
> long tmo;
>
> if (amdgpu_sriov_runtime(adev))
> - tmo = msecs_to_jiffies(amdgpu_lockup_timeout);
> + tmo = msecs_to_jiffies(8000);
Actually, I do not understand the change at all. Isnâ??t that a module
parameter?
```
$ git grep amdgpu_lockup_timeout
drivers/gpu/drm/amd/amdgpu/amdgpu.h:extern int amdgpu_lockup_timeout;
drivers/gpu/drm/amd/amdgpu/amdgpu_device.c: if (amdgpu_lockup_timeout == 0) {
drivers/gpu/drm/amd/amdgpu/amdgpu_device.c: amdgpu_lockup_timeout = 10000;
drivers/gpu/drm/amd/amdgpu/amdgpu_device.c: tmo = msecs_to_jiffies(amdgpu_lockup_timeout);
drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c:int amdgpu_lockup_timeout = 10000;
drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c:module_param_named(lockup_timeout, amdgpu_lockup_timeout, int, 0444);
drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c: timeout = msecs_to_jiffies(amdgpu_lockup_timeout);
drivers/gpu/drm/amd/amdgpu/mxgpu_ai.c: if (amdgpu_lockup_timeout == 0)
```
So, if itâ??s not set, the time-out is set to 10(!) seconds anyway,
isnâ??t it? What am I missing?
> else
> tmo = msecs_to_jiffies(100);
>
>
In my opinion, such time-outs need to have a big FIXME added to
it, and VFâ??s exclusive time-outs should be drastically decreased.
Kind regards,
Paul
