From: Daniel Vetter <daniel@ffwll.ch>
To: Andrey Grodzovsky <Andrey.Grodzovsky@amd.com>
Cc: daniel.vetter@ffwll.ch, michel@daenzer.net,
dri-devel@lists.freedesktop.org, ppaalanen@gmail.com,
amd-gfx@lists.freedesktop.org, Daniel Vetter <daniel@ffwll.ch>,
ckoenig.leichtzumerken@gmail.com, alexdeucher@gmail.com
Subject: Re: [PATCH v2 8/8] drm/amdgpu: Prevent any job recoveries after device is unplugged.
Date: Tue, 17 Nov 2020 20:49:22 +0100 [thread overview]
Message-ID: <20201117194922.GW401619@phenom.ffwll.local> (raw)
In-Reply-To: <b827fa7a-d89e-d138-d275-60a9f15c128a@amd.com>
On Tue, Nov 17, 2020 at 02:18:49PM -0500, Andrey Grodzovsky wrote:
>
> On 11/17/20 1:52 PM, Daniel Vetter wrote:
> > On Tue, Nov 17, 2020 at 01:38:14PM -0500, Andrey Grodzovsky wrote:
> > > On 6/22/20 5:53 AM, Daniel Vetter wrote:
> > > > On Sun, Jun 21, 2020 at 02:03:08AM -0400, Andrey Grodzovsky wrote:
> > > > > No point to try recovery if device is gone, just messes up things.
> > > > >
> > > > > Signed-off-by: Andrey Grodzovsky <andrey.grodzovsky@amd.com>
> > > > > ---
> > > > > drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c | 16 ++++++++++++++++
> > > > > drivers/gpu/drm/amd/amdgpu/amdgpu_job.c | 8 ++++++++
> > > > > 2 files changed, 24 insertions(+)
> > > > >
> > > > > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> > > > > index 6932d75..5d6d3d9 100644
> > > > > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> > > > > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> > > > > @@ -1129,12 +1129,28 @@ static int amdgpu_pci_probe(struct pci_dev *pdev,
> > > > > return ret;
> > > > > }
> > > > > +static void amdgpu_cancel_all_tdr(struct amdgpu_device *adev)
> > > > > +{
> > > > > + int i;
> > > > > +
> > > > > + for (i = 0; i < AMDGPU_MAX_RINGS; ++i) {
> > > > > + struct amdgpu_ring *ring = adev->rings[i];
> > > > > +
> > > > > + if (!ring || !ring->sched.thread)
> > > > > + continue;
> > > > > +
> > > > > + cancel_delayed_work_sync(&ring->sched.work_tdr);
> > > > > + }
> > > > > +}
> > > > I think this is a function that's supposed to be in drm/scheduler, not
> > > > here. Might also just be your cleanup code being ordered wrongly, or your
> > > > split in one of the earlier patches not done quite right.
> > > > -Daniel
> > >
> > > This function iterates across all the schedulers per amdgpu device and accesses
> > > amdgpu specific structures , drm/scheduler deals with single scheduler at most
> > > so looks to me like this is the right place for this function
> > I guess we could keep track of all schedulers somewhere in a list in
> > struct drm_device and wrap this up. That was kinda the idea.
> >
> > Minimally I think a tiny wrapper with docs for the
> > cancel_delayed_work_sync(&sched->work_tdr); which explains what you must
> > observe to make sure there's no race.
>
>
> Will do
>
>
> > I'm not exactly sure there's no
> > guarantee here we won't get a new tdr work launched right afterwards at
> > least, so this looks a bit like a hack.
>
>
> Note that for any TDR work happening post amdgpu_cancel_all_tdr
> amdgpu_job_timedout->drm_dev_is_unplugged
> will return true and so it will return early. To make it water proof tight
> against race
> i can switch from drm_dev_is_unplugged to drm_dev_enter/exit
Hm that's confusing. You do a work_cancel_sync, so that at least looks
like "tdr work must not run after this point"
If you only rely on drm_dev_enter/exit check with the tdr work, then
there's no need to cancel anything.
For race free cancel_work_sync you need:
1. make sure whatever is calling schedule_work is guaranteed to no longer
call schedule_work.
2. call cancel_work_sync
Anything else is cargo-culted work cleanup:
- 1. without 2. means if a work got scheduled right before it'll still be
a problem.
- 2. without 1. means a schedule_work right after makes you calling
cancel_work_sync pointless.
So either both or nothing.
-Daniel
>
> Andrey
>
>
> > -Daniel
> >
> > > Andrey
> > >
> > >
> > > > > +
> > > > > static void
> > > > > amdgpu_pci_remove(struct pci_dev *pdev)
> > > > > {
> > > > > struct drm_device *dev = pci_get_drvdata(pdev);
> > > > > + struct amdgpu_device *adev = dev->dev_private;
> > > > > drm_dev_unplug(dev);
> > > > > + amdgpu_cancel_all_tdr(adev);
> > > > > ttm_bo_unmap_virtual_address_space(&adev->mman.bdev);
> > > > > amdgpu_driver_unload_kms(dev);
> > > > > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c
> > > > > index 4720718..87ff0c0 100644
> > > > > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c
> > > > > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c
> > > > > @@ -28,6 +28,8 @@
> > > > > #include "amdgpu.h"
> > > > > #include "amdgpu_trace.h"
> > > > > +#include <drm/drm_drv.h>
> > > > > +
> > > > > static void amdgpu_job_timedout(struct drm_sched_job *s_job)
> > > > > {
> > > > > struct amdgpu_ring *ring = to_amdgpu_ring(s_job->sched);
> > > > > @@ -37,6 +39,12 @@ static void amdgpu_job_timedout(struct drm_sched_job *s_job)
> > > > > memset(&ti, 0, sizeof(struct amdgpu_task_info));
> > > > > + if (drm_dev_is_unplugged(adev->ddev)) {
> > > > > + DRM_INFO("ring %s timeout, but device unplugged, skipping.\n",
> > > > > + s_job->sched->name);
> > > > > + return;
> > > > > + }
> > > > > +
> > > > > if (amdgpu_ring_soft_recovery(ring, job->vmid, s_job->s_fence->parent)) {
> > > > > DRM_ERROR("ring %s timeout, but soft recovered\n",
> > > > > s_job->sched->name);
> > > > > --
> > > > > 2.7.4
> > > > >
--
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch
_______________________________________________
amd-gfx mailing list
amd-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/amd-gfx
next prev parent reply other threads:[~2020-11-17 19:49 UTC|newest]
Thread overview: 97+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-06-21 6:03 [PATCH v2 0/8] RFC Support hot device unplug in amdgpu Andrey Grodzovsky
2020-06-21 6:03 ` [PATCH v2 1/8] drm: Add dummy page per device or GEM object Andrey Grodzovsky
2020-06-22 9:35 ` Daniel Vetter
2020-06-22 14:21 ` Pekka Paalanen
2020-06-22 14:24 ` Daniel Vetter
2020-06-22 14:28 ` Pekka Paalanen
2020-11-09 20:34 ` Andrey Grodzovsky
2020-11-15 6:39 ` Andrey Grodzovsky
2020-06-22 13:18 ` Christian König
2020-06-22 14:23 ` Daniel Vetter
2020-06-22 14:32 ` Andrey Grodzovsky
2020-06-22 17:45 ` Christian König
2020-06-22 17:50 ` Daniel Vetter
2020-11-09 20:53 ` Andrey Grodzovsky
2020-11-13 20:52 ` Andrey Grodzovsky
2020-11-14 8:41 ` Christian König
2020-11-14 9:51 ` Daniel Vetter
2020-11-14 9:57 ` Daniel Vetter
2020-11-16 9:42 ` Michel Dänzer
2020-11-15 6:34 ` Andrey Grodzovsky
2020-11-16 9:48 ` Christian König
2020-11-16 19:00 ` Andrey Grodzovsky
2020-11-16 20:36 ` Christian König
2020-11-16 20:42 ` Andrey Grodzovsky
2020-11-19 10:01 ` Christian König
2020-06-21 6:03 ` [PATCH v2 2/8] drm/ttm: Remap all page faults to per process dummy page Andrey Grodzovsky
2020-06-22 9:41 ` Daniel Vetter
2020-06-24 3:31 ` Andrey Grodzovsky
2020-06-24 7:19 ` Daniel Vetter
2020-11-10 17:41 ` Andrey Grodzovsky
2020-06-22 19:30 ` Christian König
2020-06-21 6:03 ` [PATCH v2 3/8] drm/ttm: Add unampping of the entire device address space Andrey Grodzovsky
2020-06-22 9:45 ` Daniel Vetter
2020-06-23 5:00 ` Andrey Grodzovsky
2020-06-23 10:25 ` Daniel Vetter
2020-06-23 12:55 ` Christian König
2020-06-22 19:37 ` Christian König
2020-06-22 19:47 ` Alex Deucher
2020-06-21 6:03 ` [PATCH v2 4/8] drm/amdgpu: Split amdgpu_device_fini into early and late Andrey Grodzovsky
2020-06-22 9:48 ` Daniel Vetter
2020-11-12 4:19 ` Andrey Grodzovsky
2020-11-12 9:29 ` Daniel Vetter
2020-06-21 6:03 ` [PATCH v2 5/8] drm/amdgpu: Refactor sysfs removal Andrey Grodzovsky
2020-06-22 9:51 ` Daniel Vetter
2020-06-22 11:21 ` Greg KH
2020-06-22 16:07 ` Andrey Grodzovsky
2020-06-22 16:45 ` Greg KH
2020-06-23 4:51 ` Andrey Grodzovsky
2020-06-23 6:05 ` Greg KH
2020-06-24 3:04 ` Andrey Grodzovsky
2020-06-24 6:11 ` Greg KH
2020-06-25 1:52 ` Andrey Grodzovsky
2020-11-10 17:54 ` Andrey Grodzovsky
2020-11-10 17:59 ` Greg KH
2020-11-11 15:13 ` Andrey Grodzovsky
2020-11-11 15:34 ` Greg KH
2020-11-11 15:45 ` Andrey Grodzovsky
2020-11-11 16:06 ` Greg KH
2020-11-11 16:34 ` Andrey Grodzovsky
2020-12-02 15:48 ` Andrey Grodzovsky
2020-12-02 17:34 ` Greg KH
2020-12-02 18:02 ` Andrey Grodzovsky
2020-12-02 18:20 ` Greg KH
2020-12-02 18:40 ` Andrey Grodzovsky
2020-06-22 13:19 ` Christian König
2020-06-21 6:03 ` [PATCH v2 6/8] drm/amdgpu: Unmap entire device address space on device remove Andrey Grodzovsky
2020-06-22 9:56 ` Daniel Vetter
2020-06-22 19:38 ` Christian König
2020-06-22 19:48 ` Alex Deucher
2020-06-23 10:22 ` Daniel Vetter
2020-06-23 13:16 ` Christian König
2020-06-24 3:12 ` Andrey Grodzovsky
2020-06-21 6:03 ` [PATCH v2 7/8] drm/amdgpu: Fix sdma code crash post device unplug Andrey Grodzovsky
2020-06-22 9:55 ` Daniel Vetter
2020-06-22 19:40 ` Christian König
2020-06-23 5:11 ` Andrey Grodzovsky
2020-06-23 7:14 ` Christian König
2020-06-21 6:03 ` [PATCH v2 8/8] drm/amdgpu: Prevent any job recoveries after device is unplugged Andrey Grodzovsky
2020-06-22 9:53 ` Daniel Vetter
2020-11-17 18:38 ` Andrey Grodzovsky
2020-11-17 18:52 ` Daniel Vetter
2020-11-17 19:18 ` Andrey Grodzovsky
2020-11-17 19:49 ` Daniel Vetter [this message]
2020-11-17 20:07 ` Andrey Grodzovsky
2020-11-18 7:39 ` Daniel Vetter
2020-11-18 12:01 ` Christian König
2020-11-18 15:43 ` Luben Tuikov
2020-11-18 16:20 ` Andrey Grodzovsky
2020-11-19 7:55 ` Christian König
2020-11-19 15:02 ` Andrey Grodzovsky
2020-11-19 15:29 ` Daniel Vetter
2020-11-19 21:24 ` Andrey Grodzovsky
2020-11-18 0:46 ` Luben Tuikov
2020-06-22 9:46 ` [PATCH v2 0/8] RFC Support hot device unplug in amdgpu Daniel Vetter
2020-06-23 5:14 ` Andrey Grodzovsky
2020-06-23 9:04 ` Michel Dänzer
2020-06-24 3:21 ` Andrey Grodzovsky
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20201117194922.GW401619@phenom.ffwll.local \
--to=daniel@ffwll.ch \
--cc=Andrey.Grodzovsky@amd.com \
--cc=alexdeucher@gmail.com \
--cc=amd-gfx@lists.freedesktop.org \
--cc=ckoenig.leichtzumerken@gmail.com \
--cc=daniel.vetter@ffwll.ch \
--cc=dri-devel@lists.freedesktop.org \
--cc=michel@daenzer.net \
--cc=ppaalanen@gmail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).