diff mbox

drm/nouveau: Fix pre-nv50 pageflip events (v3)

Message ID 1447167452-998-1-git-send-email-mario.kleiner.de@gmail.com (mailing list archive)
State New, archived
Headers show

Commit Message

Mario Kleiner Nov. 10, 2015, 2:54 p.m. UTC
From: Daniel Vetter <daniel.vetter@ffwll.ch>

Apparently pre-nv50 pageflip events happen before the actual vblank
period. Therefore that functionality got semi-disabled in

commit af4870e406126b7ac0ae7c7ce5751f25ebe60f28
Author: Mario Kleiner <mario.kleiner.de@gmail.com>
Date:   Tue May 13 00:42:08 2014 +0200

    drm/nouveau/kms/nv04-nv40: fix pageflip events via special case.

Unfortunately that hack got uprooted in

commit cc1ef118fc099295ae6aabbacc8af94d8d8885eb
Author: Thierry Reding <treding@nvidia.com>
Date:   Wed Aug 12 17:00:31 2015 +0200

    drm/irq: Make pipe unsigned and name consistent

Trigering a warning when trying to sample the vblank timestamp for a
non-existing pipe. There's a few ways to fix this:

- Open-code the old behaviour, which just enshrines this slight
  breakage of the userspace ABI.

- Revert Mario's commit and again inflict broken timestamps, again not
  pretty.

- Fix this for real by delaying the pageflip TS until the next vblank
  interrupt, thereby making it accurate.

This patch implements the third option. Since having a page flip
interrupt that happens when the pageflip gets armed and not when it
completes in the next vblank seems to be fairly common (older i915 hw
works very similarly) create a new helper to arm vblank events for
such drivers.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=106431
Cc: Thierry Reding <treding@nvidia.com>
Cc: Mario Kleiner <mario.kleiner.de@gmail.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Ilia Mirkin <imirkin@alum.mit.edu>

v2 (mario): Integrate my own review comments into Daniels patch.
   - Fix function prototypes in drmP.h
   - Add missing vblank_put() for pageflip completion without
     pageflip event.
   - Initialize sequence number for queued pageflip event to avoid
     trouble in drm_handle_vblank_events().
   - Remove dead code and spelling fix.

v3 (mario): Add a signed-off-by and cc stable tag per Ilja's advice.

Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
(v1) Reviewed-by: Mario Kleiner <mario.kleiner.de@gmail.com>
(v2/v3) Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com>

Cc: stable@vger.kernel.org # v4.3
---
 drivers/gpu/drm/drm_irq.c                 | 54 ++++++++++++++++++++++++++++++-
 drivers/gpu/drm/nouveau/nouveau_display.c | 19 ++++++-----
 include/drm/drmP.h                        |  4 +++
 3 files changed, 68 insertions(+), 9 deletions(-)

Comments

Thierry Reding Nov. 10, 2015, 4 p.m. UTC | #1
On Tue, Nov 10, 2015 at 03:54:52PM +0100, Mario Kleiner wrote:
> From: Daniel Vetter <daniel.vetter@ffwll.ch>
> 
> Apparently pre-nv50 pageflip events happen before the actual vblank
> period. Therefore that functionality got semi-disabled in
> 
> commit af4870e406126b7ac0ae7c7ce5751f25ebe60f28
> Author: Mario Kleiner <mario.kleiner.de@gmail.com>
> Date:   Tue May 13 00:42:08 2014 +0200
> 
>     drm/nouveau/kms/nv04-nv40: fix pageflip events via special case.
> 
> Unfortunately that hack got uprooted in
> 
> commit cc1ef118fc099295ae6aabbacc8af94d8d8885eb
> Author: Thierry Reding <treding@nvidia.com>
> Date:   Wed Aug 12 17:00:31 2015 +0200
> 
>     drm/irq: Make pipe unsigned and name consistent
> 
> Trigering a warning when trying to sample the vblank timestamp for a
> non-existing pipe. There's a few ways to fix this:
> 
> - Open-code the old behaviour, which just enshrines this slight
>   breakage of the userspace ABI.
> 
> - Revert Mario's commit and again inflict broken timestamps, again not
>   pretty.
> 
> - Fix this for real by delaying the pageflip TS until the next vblank
>   interrupt, thereby making it accurate.
> 
> This patch implements the third option. Since having a page flip
> interrupt that happens when the pageflip gets armed and not when it
> completes in the next vblank seems to be fairly common (older i915 hw
> works very similarly) create a new helper to arm vblank events for
> such drivers.
> 
> Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=106431
> Cc: Thierry Reding <treding@nvidia.com>
> Cc: Mario Kleiner <mario.kleiner.de@gmail.com>
> Cc: Ben Skeggs <bskeggs@redhat.com>
> Cc: Ilia Mirkin <imirkin@alum.mit.edu>
> 
> v2 (mario): Integrate my own review comments into Daniels patch.
>    - Fix function prototypes in drmP.h
>    - Add missing vblank_put() for pageflip completion without
>      pageflip event.
>    - Initialize sequence number for queued pageflip event to avoid
>      trouble in drm_handle_vblank_events().
>    - Remove dead code and spelling fix.
> 
> v3 (mario): Add a signed-off-by and cc stable tag per Ilja's advice.
> 
> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
> (v1) Reviewed-by: Mario Kleiner <mario.kleiner.de@gmail.com>
> (v2/v3) Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com>
> 
> Cc: stable@vger.kernel.org # v4.3
> ---
>  drivers/gpu/drm/drm_irq.c                 | 54 ++++++++++++++++++++++++++++++-
>  drivers/gpu/drm/nouveau/nouveau_display.c | 19 ++++++-----
>  include/drm/drmP.h                        |  4 +++
>  3 files changed, 68 insertions(+), 9 deletions(-)

This looks good to me. Let me clean this up a little and submit it to
Dave.

Thierry
Mario Kleiner Nov. 10, 2015, 4:25 p.m. UTC | #2
On 11/10/2015 05:00 PM, Thierry Reding wrote:
> On Tue, Nov 10, 2015 at 03:54:52PM +0100, Mario Kleiner wrote:
>> From: Daniel Vetter <daniel.vetter@ffwll.ch>
>>
>> Apparently pre-nv50 pageflip events happen before the actual vblank
>> period. Therefore that functionality got semi-disabled in
>>
>> commit af4870e406126b7ac0ae7c7ce5751f25ebe60f28
>> Author: Mario Kleiner <mario.kleiner.de@gmail.com>
>> Date:   Tue May 13 00:42:08 2014 +0200
>>
>>      drm/nouveau/kms/nv04-nv40: fix pageflip events via special case.
>>
>> Unfortunately that hack got uprooted in
>>
>> commit cc1ef118fc099295ae6aabbacc8af94d8d8885eb
>> Author: Thierry Reding <treding@nvidia.com>
>> Date:   Wed Aug 12 17:00:31 2015 +0200
>>
>>      drm/irq: Make pipe unsigned and name consistent
>>
>> Trigering a warning when trying to sample the vblank timestamp for a
>> non-existing pipe. There's a few ways to fix this:
>>
>> - Open-code the old behaviour, which just enshrines this slight
>>    breakage of the userspace ABI.
>>
>> - Revert Mario's commit and again inflict broken timestamps, again not
>>    pretty.
>>
>> - Fix this for real by delaying the pageflip TS until the next vblank
>>    interrupt, thereby making it accurate.
>>
>> This patch implements the third option. Since having a page flip
>> interrupt that happens when the pageflip gets armed and not when it
>> completes in the next vblank seems to be fairly common (older i915 hw
>> works very similarly) create a new helper to arm vblank events for
>> such drivers.
>>
>> Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=106431
>> Cc: Thierry Reding <treding@nvidia.com>
>> Cc: Mario Kleiner <mario.kleiner.de@gmail.com>
>> Cc: Ben Skeggs <bskeggs@redhat.com>
>> Cc: Ilia Mirkin <imirkin@alum.mit.edu>
>>
>> v2 (mario): Integrate my own review comments into Daniels patch.
>>     - Fix function prototypes in drmP.h
>>     - Add missing vblank_put() for pageflip completion without
>>       pageflip event.
>>     - Initialize sequence number for queued pageflip event to avoidng
>>       trouble in drm_handle_vblank_events().
>>     - Remove dead code and spelling fix.
>>
>> v3 (mario): Add a signed-off-by and cc stable tag per Ilja's advice.
>>
>> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
>> (v1) Reviewed-by: Mario Kleiner <mario.kleiner.de@gmail.com>
>> (v2/v3) Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com>
>>
>> Cc: stable@vger.kernel.org # v4.3
>> ---
>>   drivers/gpu/drm/drm_irq.c                 | 54 ++++++++++++++++++++++++++++++-
>>   drivers/gpu/drm/nouveau/nouveau_display.c | 19 ++++++-----
>>   include/drm/drmP.h                        |  4 +++
>>   3 files changed, 68 insertions(+), 9 deletions(-)
>
> This looks good to me. Let me clean this up a little and submit it to
> Dave.
>
> Thierry
>

Btw., if somebody has a functional old card for testing this, it should 
be easy to verify if it works on pre-nv50. If it would not work it would 
deliver the pageflip event 1 frame delayed, so at least on standard 
nouveau + default DRI2 + default double-buffering the rate for a tight 
loop of page-flipped swaps should go down to 30 fps on a 60 Hz display, 
quite noticeable. Afaik we also have Piglit tests for OML_sync_control 
which would likely fail if this would be broken.

Oh and if someone has tips on how to resurrect an old nv-40 PC (booted 
with BIOS only) graphics card in a MacPro (EFI boot), i wouldn't mind 
hearing them. It would be nice to still be able to use that card for 
testing.

thanks,
-mario
poma Nov. 11, 2015, 8:12 p.m. UTC | #3
On 10.11.2015 17:25, Mario Kleiner wrote:
> On 11/10/2015 05:00 PM, Thierry Reding wrote:
>> On Tue, Nov 10, 2015 at 03:54:52PM +0100, Mario Kleiner wrote:
>>> From: Daniel Vetter <daniel.vetter@ffwll.ch>
>>>
>>> Apparently pre-nv50 pageflip events happen before the actual vblank
>>> period. Therefore that functionality got semi-disabled in
>>>
>>> commit af4870e406126b7ac0ae7c7ce5751f25ebe60f28
>>> Author: Mario Kleiner <mario.kleiner.de@gmail.com>
>>> Date:   Tue May 13 00:42:08 2014 +0200
>>>
>>>      drm/nouveau/kms/nv04-nv40: fix pageflip events via special case.
>>>
>>> Unfortunately that hack got uprooted in
>>>
>>> commit cc1ef118fc099295ae6aabbacc8af94d8d8885eb
>>> Author: Thierry Reding <treding@nvidia.com>
>>> Date:   Wed Aug 12 17:00:31 2015 +0200
>>>
>>>      drm/irq: Make pipe unsigned and name consistent
>>>
>>> Trigering a warning when trying to sample the vblank timestamp for a
>>> non-existing pipe. There's a few ways to fix this:
>>>
>>> - Open-code the old behaviour, which just enshrines this slight
>>>    breakage of the userspace ABI.
>>>
>>> - Revert Mario's commit and again inflict broken timestamps, again not
>>>    pretty.
>>>
>>> - Fix this for real by delaying the pageflip TS until the next vblank
>>>    interrupt, thereby making it accurate.
>>>
>>> This patch implements the third option. Since having a page flip
>>> interrupt that happens when the pageflip gets armed and not when it
>>> completes in the next vblank seems to be fairly common (older i915 hw
>>> works very similarly) create a new helper to arm vblank events for
>>> such drivers.
>>>
>>> Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=106431
>>> Cc: Thierry Reding <treding@nvidia.com>
>>> Cc: Mario Kleiner <mario.kleiner.de@gmail.com>
>>> Cc: Ben Skeggs <bskeggs@redhat.com>
>>> Cc: Ilia Mirkin <imirkin@alum.mit.edu>
>>>
>>> v2 (mario): Integrate my own review comments into Daniels patch.
>>>     - Fix function prototypes in drmP.h
>>>     - Add missing vblank_put() for pageflip completion without
>>>       pageflip event.
>>>     - Initialize sequence number for queued pageflip event to avoidng
>>>       trouble in drm_handle_vblank_events().
>>>     - Remove dead code and spelling fix.
>>>
>>> v3 (mario): Add a signed-off-by and cc stable tag per Ilja's advice.
>>>
>>> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
>>> (v1) Reviewed-by: Mario Kleiner <mario.kleiner.de@gmail.com>
>>> (v2/v3) Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com>
>>>
>>> Cc: stable@vger.kernel.org # v4.3
>>> ---
>>>   drivers/gpu/drm/drm_irq.c                 | 54 ++++++++++++++++++++++++++++++-
>>>   drivers/gpu/drm/nouveau/nouveau_display.c | 19 ++++++-----
>>>   include/drm/drmP.h                        |  4 +++
>>>   3 files changed, 68 insertions(+), 9 deletions(-)
>>
>> This looks good to me. Let me clean this up a little and submit it to
>> Dave.
>>
>> Thierry
>>
> 
> Btw., if somebody has a functional old card for testing this, it should 
> be easy to verify if it works on pre-nv50. If it would not work it would 
> deliver the pageflip event 1 frame delayed, so at least on standard 
> nouveau + default DRI2 + default double-buffering the rate for a tight 
> loop of page-flipped swaps should go down to 30 fps on a 60 Hz display, 
> quite noticeable. Afaik we also have Piglit tests for OML_sync_control 
> which would likely fail if this would be broken.
> 
> Oh and if someone has tips on how to resurrect an old nv-40 PC (booted 
> with BIOS only) graphics card in a MacPro (EFI boot), i wouldn't mind 
> hearing them. It would be nice to still be able to use that card for 
> testing.
> 
> thanks,
> -mario


------------[ cut here ]------------
WARNING: CPU: 0 PID: 313 at lib/dma-debug.c:1205 check_sync+0x169/0x6e0()
nouveau 0000:01:00.0: DMA-API: device driver tries to sync DMA memory it has not allocated [device address=0x00000000c0bf6468] [size=4096 bytes]
Modules linked in: nouveau(+) ...
CPU: 0 PID: 313 Comm: systemd-udevd Not tainted 4.3.0-3.fc22.i686+debug #1
...
Call Trace:
 [<c078a28f>] dump_stack+0x48/0x69
 [<c0461fc7>] warn_slowpath_common+0x87/0xc0
 [<c07b9029>] ? check_sync+0x169/0x6e0
 [<c07b9029>] ? check_sync+0x169/0x6e0
 [<c046203e>] warn_slowpath_fmt+0x3e/0x60
 [<c07b9029>] check_sync+0x169/0x6e0
 [<c07b96ad>] debug_dma_sync_single_for_device+0x7d/0x90
 [<f7ece298>] ? ttm_bo_del_sub_from_lru+0x18/0x50 [ttm]
 [<c040bef0>] ? text_poke_bp+0xd0/0xd0
 [<f85d96db>] nouveau_bo_sync_for_device+0x8b/0xa0 [nouveau]
 [<f85d97c4>] nouveau_bo_validate+0x34/0x40 [nouveau]
 [<f85d9958>] nouveau_bo_pin+0x188/0x290 [nouveau]
 [<f85d7fe0>] ? nv10_bo_put_tile_region+0x80/0x80 [nouveau]
 [<f85ec7fd>] nouveau_channel_prep+0xfd/0x2c0 [nouveau]
 [<f85eca17>] nouveau_channel_new+0x57/0x7a0 [nouveau]
 [<c05da57c>] ? kfree+0xdc/0x280
 [<f8540082>] ? nvif_object_sclass_put+0x12/0x20 [nouveau]
 [<f85d5666>] nouveau_drm_load+0x596/0x8d0 [nouveau]
 [<c04bc14c>] ? trace_hardirqs_on_caller+0x12c/0x1d0
 [<f7e8bfe9>] ? drm_minor_register+0x89/0x120 [drm]
 [<f7e8c116>] drm_dev_register+0x96/0xa0 [drm]
 [<f7e8ece9>] drm_get_pci_dev+0x79/0x1c0 [drm]
 [<c07d973e>] ? pcibios_set_master+0x4e/0xa0
 [<f85d5b8e>] nouveau_drm_probe+0x1ee/0x220 [nouveau]
 [<c07dbf3b>] pci_device_probe+0x7b/0xf0
 [<c08bf366>] ? devices_kset_move_last+0x56/0xa0
 [<c08c2de4>] driver_probe_device+0x204/0x490
 [<c08c30bc>] ? __driver_attach+0x4c/0x90
 [<c07dbc02>] ? pci_match_device+0xd2/0x100
 [<c08c30f1>] __driver_attach+0x81/0x90
 [<c08c3070>] ? driver_probe_device+0x490/0x490
 [<c08c0b97>] bus_for_each_dev+0x57/0xa0
 [<c08c25ce>] driver_attach+0x1e/0x20
 [<c08c3070>] ? driver_probe_device+0x490/0x490
 [<c08c214f>] bus_add_driver+0x1ef/0x290
 [<c08c3bdd>] driver_register+0x5d/0xf0
 [<c07da71a>] __pci_register_driver+0x4a/0x50
 [<f7e8ef0d>] drm_pci_init+0xdd/0x100 [drm]
 [<f7f211f9>] nouveau_drm_init+0x1f9/0x1000 [nouveau]
 [<f7f21000>] ? 0xf7f21000
 [<c040047a>] do_one_initcall+0xaa/0x200
 [<f7f21000>] ? 0xf7f21000
 [<c04dae42>] ? rcu_read_lock_sched_held+0x42/0x80
 [<c05daf0d>] ? kmem_cache_alloc_trace+0x23d/0x310
 [<c0582dd1>] ? do_init_module+0x21/0x1b7
 [<c0582dd1>] ? do_init_module+0x21/0x1b7
 [<c0582e00>] do_init_module+0x50/0x1b7
 [<c05036ec>] load_module+0x1ebc/0x2550
 [<c0b993d7>] ? _raw_spin_unlock_irq+0x27/0x40
 [<c048e6aa>] ? finish_task_switch+0x8a/0x1d0
 [<c0503ec7>] SyS_init_module+0x147/0x1a0
 [<c04012c4>] ? do_audit_syscall_entry.isra.9+0x44/0x50
 [<c0401627>] ? syscall_trace_enter_phase1+0x107/0x130
 [<c0b99f05>] syscall_call+0x7/0x7
---[ end trace d3c14159641a1388 ]---


NV34 tested with 4.3.0-3.fc22.i686
i.e. 4.3.0-1.fc24.i686 & drm-nouveau-Fix-pre-nv50-pageflip-events-v4.patch

http://koji.fedoraproject.org/koji/buildinfo?buildID=695636
https://patchwork.kernel.org/patch/7591531/mbox
Thierry Reding Nov. 12, 2015, 1:48 p.m. UTC | #4
On Wed, Nov 11, 2015 at 09:12:33PM +0100, poma wrote:
> On 10.11.2015 17:25, Mario Kleiner wrote:
> > On 11/10/2015 05:00 PM, Thierry Reding wrote:
> >> On Tue, Nov 10, 2015 at 03:54:52PM +0100, Mario Kleiner wrote:
> >>> From: Daniel Vetter <daniel.vetter@ffwll.ch>
> >>>
> >>> Apparently pre-nv50 pageflip events happen before the actual vblank
> >>> period. Therefore that functionality got semi-disabled in
> >>>
> >>> commit af4870e406126b7ac0ae7c7ce5751f25ebe60f28
> >>> Author: Mario Kleiner <mario.kleiner.de@gmail.com>
> >>> Date:   Tue May 13 00:42:08 2014 +0200
> >>>
> >>>      drm/nouveau/kms/nv04-nv40: fix pageflip events via special case.
> >>>
> >>> Unfortunately that hack got uprooted in
> >>>
> >>> commit cc1ef118fc099295ae6aabbacc8af94d8d8885eb
> >>> Author: Thierry Reding <treding@nvidia.com>
> >>> Date:   Wed Aug 12 17:00:31 2015 +0200
> >>>
> >>>      drm/irq: Make pipe unsigned and name consistent
> >>>
> >>> Trigering a warning when trying to sample the vblank timestamp for a
> >>> non-existing pipe. There's a few ways to fix this:
> >>>
> >>> - Open-code the old behaviour, which just enshrines this slight
> >>>    breakage of the userspace ABI.
> >>>
> >>> - Revert Mario's commit and again inflict broken timestamps, again not
> >>>    pretty.
> >>>
> >>> - Fix this for real by delaying the pageflip TS until the next vblank
> >>>    interrupt, thereby making it accurate.
> >>>
> >>> This patch implements the third option. Since having a page flip
> >>> interrupt that happens when the pageflip gets armed and not when it
> >>> completes in the next vblank seems to be fairly common (older i915 hw
> >>> works very similarly) create a new helper to arm vblank events for
> >>> such drivers.
> >>>
> >>> Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=106431
> >>> Cc: Thierry Reding <treding@nvidia.com>
> >>> Cc: Mario Kleiner <mario.kleiner.de@gmail.com>
> >>> Cc: Ben Skeggs <bskeggs@redhat.com>
> >>> Cc: Ilia Mirkin <imirkin@alum.mit.edu>
> >>>
> >>> v2 (mario): Integrate my own review comments into Daniels patch.
> >>>     - Fix function prototypes in drmP.h
> >>>     - Add missing vblank_put() for pageflip completion without
> >>>       pageflip event.
> >>>     - Initialize sequence number for queued pageflip event to avoidng
> >>>       trouble in drm_handle_vblank_events().
> >>>     - Remove dead code and spelling fix.
> >>>
> >>> v3 (mario): Add a signed-off-by and cc stable tag per Ilja's advice.
> >>>
> >>> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
> >>> (v1) Reviewed-by: Mario Kleiner <mario.kleiner.de@gmail.com>
> >>> (v2/v3) Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com>
> >>>
> >>> Cc: stable@vger.kernel.org # v4.3
> >>> ---
> >>>   drivers/gpu/drm/drm_irq.c                 | 54 ++++++++++++++++++++++++++++++-
> >>>   drivers/gpu/drm/nouveau/nouveau_display.c | 19 ++++++-----
> >>>   include/drm/drmP.h                        |  4 +++
> >>>   3 files changed, 68 insertions(+), 9 deletions(-)
> >>
> >> This looks good to me. Let me clean this up a little and submit it to
> >> Dave.
> >>
> >> Thierry
> >>
> > 
> > Btw., if somebody has a functional old card for testing this, it should 
> > be easy to verify if it works on pre-nv50. If it would not work it would 
> > deliver the pageflip event 1 frame delayed, so at least on standard 
> > nouveau + default DRI2 + default double-buffering the rate for a tight 
> > loop of page-flipped swaps should go down to 30 fps on a 60 Hz display, 
> > quite noticeable. Afaik we also have Piglit tests for OML_sync_control 
> > which would likely fail if this would be broken.
> > 
> > Oh and if someone has tips on how to resurrect an old nv-40 PC (booted 
> > with BIOS only) graphics card in a MacPro (EFI boot), i wouldn't mind 
> > hearing them. It would be nice to still be able to use that card for 
> > testing.
> > 
> > thanks,
> > -mario
> 
> 
> ------------[ cut here ]------------
> WARNING: CPU: 0 PID: 313 at lib/dma-debug.c:1205 check_sync+0x169/0x6e0()
> nouveau 0000:01:00.0: DMA-API: device driver tries to sync DMA memory it has not allocated [device address=0x00000000c0bf6468] [size=4096 bytes]
> Modules linked in: nouveau(+) ...
> CPU: 0 PID: 313 Comm: systemd-udevd Not tainted 4.3.0-3.fc22.i686+debug #1
> ...
> Call Trace:
>  [<c078a28f>] dump_stack+0x48/0x69
>  [<c0461fc7>] warn_slowpath_common+0x87/0xc0
>  [<c07b9029>] ? check_sync+0x169/0x6e0
>  [<c07b9029>] ? check_sync+0x169/0x6e0
>  [<c046203e>] warn_slowpath_fmt+0x3e/0x60
>  [<c07b9029>] check_sync+0x169/0x6e0
>  [<c07b96ad>] debug_dma_sync_single_for_device+0x7d/0x90
>  [<f7ece298>] ? ttm_bo_del_sub_from_lru+0x18/0x50 [ttm]
>  [<c040bef0>] ? text_poke_bp+0xd0/0xd0
>  [<f85d96db>] nouveau_bo_sync_for_device+0x8b/0xa0 [nouveau]
>  [<f85d97c4>] nouveau_bo_validate+0x34/0x40 [nouveau]
>  [<f85d9958>] nouveau_bo_pin+0x188/0x290 [nouveau]
>  [<f85d7fe0>] ? nv10_bo_put_tile_region+0x80/0x80 [nouveau]
>  [<f85ec7fd>] nouveau_channel_prep+0xfd/0x2c0 [nouveau]
>  [<f85eca17>] nouveau_channel_new+0x57/0x7a0 [nouveau]
>  [<c05da57c>] ? kfree+0xdc/0x280
>  [<f8540082>] ? nvif_object_sclass_put+0x12/0x20 [nouveau]
>  [<f85d5666>] nouveau_drm_load+0x596/0x8d0 [nouveau]
>  [<c04bc14c>] ? trace_hardirqs_on_caller+0x12c/0x1d0
>  [<f7e8bfe9>] ? drm_minor_register+0x89/0x120 [drm]
>  [<f7e8c116>] drm_dev_register+0x96/0xa0 [drm]
>  [<f7e8ece9>] drm_get_pci_dev+0x79/0x1c0 [drm]
>  [<c07d973e>] ? pcibios_set_master+0x4e/0xa0
>  [<f85d5b8e>] nouveau_drm_probe+0x1ee/0x220 [nouveau]
>  [<c07dbf3b>] pci_device_probe+0x7b/0xf0
>  [<c08bf366>] ? devices_kset_move_last+0x56/0xa0
>  [<c08c2de4>] driver_probe_device+0x204/0x490
>  [<c08c30bc>] ? __driver_attach+0x4c/0x90
>  [<c07dbc02>] ? pci_match_device+0xd2/0x100
>  [<c08c30f1>] __driver_attach+0x81/0x90
>  [<c08c3070>] ? driver_probe_device+0x490/0x490
>  [<c08c0b97>] bus_for_each_dev+0x57/0xa0
>  [<c08c25ce>] driver_attach+0x1e/0x20
>  [<c08c3070>] ? driver_probe_device+0x490/0x490
>  [<c08c214f>] bus_add_driver+0x1ef/0x290
>  [<c08c3bdd>] driver_register+0x5d/0xf0
>  [<c07da71a>] __pci_register_driver+0x4a/0x50
>  [<f7e8ef0d>] drm_pci_init+0xdd/0x100 [drm]
>  [<f7f211f9>] nouveau_drm_init+0x1f9/0x1000 [nouveau]
>  [<f7f21000>] ? 0xf7f21000
>  [<c040047a>] do_one_initcall+0xaa/0x200
>  [<f7f21000>] ? 0xf7f21000
>  [<c04dae42>] ? rcu_read_lock_sched_held+0x42/0x80
>  [<c05daf0d>] ? kmem_cache_alloc_trace+0x23d/0x310
>  [<c0582dd1>] ? do_init_module+0x21/0x1b7
>  [<c0582dd1>] ? do_init_module+0x21/0x1b7
>  [<c0582e00>] do_init_module+0x50/0x1b7
>  [<c05036ec>] load_module+0x1ebc/0x2550
>  [<c0b993d7>] ? _raw_spin_unlock_irq+0x27/0x40
>  [<c048e6aa>] ? finish_task_switch+0x8a/0x1d0
>  [<c0503ec7>] SyS_init_module+0x147/0x1a0
>  [<c04012c4>] ? do_audit_syscall_entry.isra.9+0x44/0x50
>  [<c0401627>] ? syscall_trace_enter_phase1+0x107/0x130
>  [<c0b99f05>] syscall_call+0x7/0x7
> ---[ end trace d3c14159641a1388 ]---
> 
> 
> NV34 tested with 4.3.0-3.fc22.i686
> i.e. 4.3.0-1.fc24.i686 & drm-nouveau-Fix-pre-nv50-pageflip-events-v4.patch
> 
> http://koji.fedoraproject.org/koji/buildinfo?buildID=695636
> https://patchwork.kernel.org/patch/7591531/mbox

This doesn't look at all related and has probably been an issue for
quite some time. I /think/ this happens because memory is allocated from
the non-DMA pool (i.e. using alloc_page()) and then ends up getting run
through the dma_sync_*() API for cache maintenance. But the assumption
is that you can only do cache maintenance by the dma_sync_*() API on
memory allocated by dma_alloc_*(), hence the warning.

There was some discussion about this a while ago, and there was some
conclusion that an API was needed to do cache maintenance on non-DMA-
allocated pages of memory, but I don't think any work happened towards
that API.

Adding Alex and Arnd who had been part of that discussion, though
possibly in different threads. Guys, I've been doing too many unrelated
things lately it seems, because I can't remember where exactly we left
off. I vaguely remember that at some point somebody (maybe Russell) had
objected to adding such a non-DMA cache-maintenance API, but I can't
find a link to the relevant threads.

Thierry
poma Nov. 12, 2015, 7:07 p.m. UTC | #5
On 12.11.2015 14:48, Thierry Reding wrote:
> On Wed, Nov 11, 2015 at 09:12:33PM +0100, poma wrote:
>> On 10.11.2015 17:25, Mario Kleiner wrote:
>>> On 11/10/2015 05:00 PM, Thierry Reding wrote:
>>>> On Tue, Nov 10, 2015 at 03:54:52PM +0100, Mario Kleiner wrote:
>>>>> From: Daniel Vetter <daniel.vetter@ffwll.ch>
>>>>>
>>>>> Apparently pre-nv50 pageflip events happen before the actual vblank
>>>>> period. Therefore that functionality got semi-disabled in
>>>>>
>>>>> commit af4870e406126b7ac0ae7c7ce5751f25ebe60f28
>>>>> Author: Mario Kleiner <mario.kleiner.de@gmail.com>
>>>>> Date:   Tue May 13 00:42:08 2014 +0200
>>>>>
>>>>>      drm/nouveau/kms/nv04-nv40: fix pageflip events via special case.
>>>>>
>>>>> Unfortunately that hack got uprooted in
>>>>>
>>>>> commit cc1ef118fc099295ae6aabbacc8af94d8d8885eb
>>>>> Author: Thierry Reding <treding@nvidia.com>
>>>>> Date:   Wed Aug 12 17:00:31 2015 +0200
>>>>>
>>>>>      drm/irq: Make pipe unsigned and name consistent
>>>>>
>>>>> Trigering a warning when trying to sample the vblank timestamp for a
>>>>> non-existing pipe. There's a few ways to fix this:
>>>>>
>>>>> - Open-code the old behaviour, which just enshrines this slight
>>>>>    breakage of the userspace ABI.
>>>>>
>>>>> - Revert Mario's commit and again inflict broken timestamps, again not
>>>>>    pretty.
>>>>>
>>>>> - Fix this for real by delaying the pageflip TS until the next vblank
>>>>>    interrupt, thereby making it accurate.
>>>>>
>>>>> This patch implements the third option. Since having a page flip
>>>>> interrupt that happens when the pageflip gets armed and not when it
>>>>> completes in the next vblank seems to be fairly common (older i915 hw
>>>>> works very similarly) create a new helper to arm vblank events for
>>>>> such drivers.
>>>>>
>>>>> Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=106431
>>>>> Cc: Thierry Reding <treding@nvidia.com>
>>>>> Cc: Mario Kleiner <mario.kleiner.de@gmail.com>
>>>>> Cc: Ben Skeggs <bskeggs@redhat.com>
>>>>> Cc: Ilia Mirkin <imirkin@alum.mit.edu>
>>>>>
>>>>> v2 (mario): Integrate my own review comments into Daniels patch.
>>>>>     - Fix function prototypes in drmP.h
>>>>>     - Add missing vblank_put() for pageflip completion without
>>>>>       pageflip event.
>>>>>     - Initialize sequence number for queued pageflip event to avoidng
>>>>>       trouble in drm_handle_vblank_events().
>>>>>     - Remove dead code and spelling fix.
>>>>>
>>>>> v3 (mario): Add a signed-off-by and cc stable tag per Ilja's advice.
>>>>>
>>>>> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
>>>>> (v1) Reviewed-by: Mario Kleiner <mario.kleiner.de@gmail.com>
>>>>> (v2/v3) Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com>
>>>>>
>>>>> Cc: stable@vger.kernel.org # v4.3
>>>>> ---
>>>>>   drivers/gpu/drm/drm_irq.c                 | 54 ++++++++++++++++++++++++++++++-
>>>>>   drivers/gpu/drm/nouveau/nouveau_display.c | 19 ++++++-----
>>>>>   include/drm/drmP.h                        |  4 +++
>>>>>   3 files changed, 68 insertions(+), 9 deletions(-)
>>>>
>>>> This looks good to me. Let me clean this up a little and submit it to
>>>> Dave.
>>>>
>>>> Thierry
>>>>
>>>
>>> Btw., if somebody has a functional old card for testing this, it should 
>>> be easy to verify if it works on pre-nv50. If it would not work it would 
>>> deliver the pageflip event 1 frame delayed, so at least on standard 
>>> nouveau + default DRI2 + default double-buffering the rate for a tight 
>>> loop of page-flipped swaps should go down to 30 fps on a 60 Hz display, 
>>> quite noticeable. Afaik we also have Piglit tests for OML_sync_control 
>>> which would likely fail if this would be broken.
>>>
>>> Oh and if someone has tips on how to resurrect an old nv-40 PC (booted 
>>> with BIOS only) graphics card in a MacPro (EFI boot), i wouldn't mind 
>>> hearing them. It would be nice to still be able to use that card for 
>>> testing.
>>>
>>> thanks,
>>> -mario
>>
>>
>> ------------[ cut here ]------------
>> WARNING: CPU: 0 PID: 313 at lib/dma-debug.c:1205 check_sync+0x169/0x6e0()
>> nouveau 0000:01:00.0: DMA-API: device driver tries to sync DMA memory it has not allocated [device address=0x00000000c0bf6468] [size=4096 bytes]
>> Modules linked in: nouveau(+) ...
>> CPU: 0 PID: 313 Comm: systemd-udevd Not tainted 4.3.0-3.fc22.i686+debug #1
>> ...
>> Call Trace:
>>  [<c078a28f>] dump_stack+0x48/0x69
>>  [<c0461fc7>] warn_slowpath_common+0x87/0xc0
>>  [<c07b9029>] ? check_sync+0x169/0x6e0
>>  [<c07b9029>] ? check_sync+0x169/0x6e0
>>  [<c046203e>] warn_slowpath_fmt+0x3e/0x60
>>  [<c07b9029>] check_sync+0x169/0x6e0
>>  [<c07b96ad>] debug_dma_sync_single_for_device+0x7d/0x90
>>  [<f7ece298>] ? ttm_bo_del_sub_from_lru+0x18/0x50 [ttm]
>>  [<c040bef0>] ? text_poke_bp+0xd0/0xd0
>>  [<f85d96db>] nouveau_bo_sync_for_device+0x8b/0xa0 [nouveau]
>>  [<f85d97c4>] nouveau_bo_validate+0x34/0x40 [nouveau]
>>  [<f85d9958>] nouveau_bo_pin+0x188/0x290 [nouveau]
>>  [<f85d7fe0>] ? nv10_bo_put_tile_region+0x80/0x80 [nouveau]
>>  [<f85ec7fd>] nouveau_channel_prep+0xfd/0x2c0 [nouveau]
>>  [<f85eca17>] nouveau_channel_new+0x57/0x7a0 [nouveau]
>>  [<c05da57c>] ? kfree+0xdc/0x280
>>  [<f8540082>] ? nvif_object_sclass_put+0x12/0x20 [nouveau]
>>  [<f85d5666>] nouveau_drm_load+0x596/0x8d0 [nouveau]
>>  [<c04bc14c>] ? trace_hardirqs_on_caller+0x12c/0x1d0
>>  [<f7e8bfe9>] ? drm_minor_register+0x89/0x120 [drm]
>>  [<f7e8c116>] drm_dev_register+0x96/0xa0 [drm]
>>  [<f7e8ece9>] drm_get_pci_dev+0x79/0x1c0 [drm]
>>  [<c07d973e>] ? pcibios_set_master+0x4e/0xa0
>>  [<f85d5b8e>] nouveau_drm_probe+0x1ee/0x220 [nouveau]
>>  [<c07dbf3b>] pci_device_probe+0x7b/0xf0
>>  [<c08bf366>] ? devices_kset_move_last+0x56/0xa0
>>  [<c08c2de4>] driver_probe_device+0x204/0x490
>>  [<c08c30bc>] ? __driver_attach+0x4c/0x90
>>  [<c07dbc02>] ? pci_match_device+0xd2/0x100
>>  [<c08c30f1>] __driver_attach+0x81/0x90
>>  [<c08c3070>] ? driver_probe_device+0x490/0x490
>>  [<c08c0b97>] bus_for_each_dev+0x57/0xa0
>>  [<c08c25ce>] driver_attach+0x1e/0x20
>>  [<c08c3070>] ? driver_probe_device+0x490/0x490
>>  [<c08c214f>] bus_add_driver+0x1ef/0x290
>>  [<c08c3bdd>] driver_register+0x5d/0xf0
>>  [<c07da71a>] __pci_register_driver+0x4a/0x50
>>  [<f7e8ef0d>] drm_pci_init+0xdd/0x100 [drm]
>>  [<f7f211f9>] nouveau_drm_init+0x1f9/0x1000 [nouveau]
>>  [<f7f21000>] ? 0xf7f21000
>>  [<c040047a>] do_one_initcall+0xaa/0x200
>>  [<f7f21000>] ? 0xf7f21000
>>  [<c04dae42>] ? rcu_read_lock_sched_held+0x42/0x80
>>  [<c05daf0d>] ? kmem_cache_alloc_trace+0x23d/0x310
>>  [<c0582dd1>] ? do_init_module+0x21/0x1b7
>>  [<c0582dd1>] ? do_init_module+0x21/0x1b7
>>  [<c0582e00>] do_init_module+0x50/0x1b7
>>  [<c05036ec>] load_module+0x1ebc/0x2550
>>  [<c0b993d7>] ? _raw_spin_unlock_irq+0x27/0x40
>>  [<c048e6aa>] ? finish_task_switch+0x8a/0x1d0
>>  [<c0503ec7>] SyS_init_module+0x147/0x1a0
>>  [<c04012c4>] ? do_audit_syscall_entry.isra.9+0x44/0x50
>>  [<c0401627>] ? syscall_trace_enter_phase1+0x107/0x130
>>  [<c0b99f05>] syscall_call+0x7/0x7
>> ---[ end trace d3c14159641a1388 ]---
>>
>>
>> NV34 tested with 4.3.0-3.fc22.i686
>> i.e. 4.3.0-1.fc24.i686 & drm-nouveau-Fix-pre-nv50-pageflip-events-v4.patch
>>
>> http://koji.fedoraproject.org/koji/buildinfo?buildID=695636
>> https://patchwork.kernel.org/patch/7591531/mbox
> 
> This doesn't look at all related and has probably been an issue for
> quite some time. I /think/ this happens because memory is allocated from
> the non-DMA pool (i.e. using alloc_page()) and then ends up getting run
> through the dma_sync_*() API for cache maintenance. But the assumption
> is that you can only do cache maintenance by the dma_sync_*() API on
> memory allocated by dma_alloc_*(), hence the warning.
> 
> There was some discussion about this a while ago, and there was some
> conclusion that an API was needed to do cache maintenance on non-DMA-
> allocated pages of memory, but I don't think any work happened towards
> that API.
> 
> Adding Alex and Arnd who had been part of that discussion, though
> possibly in different threads. Guys, I've been doing too many unrelated
> things lately it seems, because I can't remember where exactly we left
> off. I vaguely remember that at some point somebody (maybe Russell) had
> objected to adding such a non-DMA cache-maintenance API, but I can't
> find a link to the relevant threads.
> 
> Thierry
> 


It's a separate issue,
this is what's left after your v4.

Fix pre-nv50 pageflip events v4
Tested-by: poma <pomidorabelisima@gmail.com>
poma Dec. 16, 2015, 11:10 a.m. UTC | #6
On 12.11.2015 14:48, Thierry Reding wrote:
> On Wed, Nov 11, 2015 at 09:12:33PM +0100, poma wrote:
>> On 10.11.2015 17:25, Mario Kleiner wrote:
>>> On 11/10/2015 05:00 PM, Thierry Reding wrote:
>>>> On Tue, Nov 10, 2015 at 03:54:52PM +0100, Mario Kleiner wrote:
>>>>> From: Daniel Vetter <daniel.vetter@ffwll.ch>
>>>>>
>>>>> Apparently pre-nv50 pageflip events happen before the actual vblank
>>>>> period. Therefore that functionality got semi-disabled in
>>>>>
>>>>> commit af4870e406126b7ac0ae7c7ce5751f25ebe60f28
>>>>> Author: Mario Kleiner <mario.kleiner.de@gmail.com>
>>>>> Date:   Tue May 13 00:42:08 2014 +0200
>>>>>
>>>>>      drm/nouveau/kms/nv04-nv40: fix pageflip events via special case.
>>>>>
>>>>> Unfortunately that hack got uprooted in
>>>>>
>>>>> commit cc1ef118fc099295ae6aabbacc8af94d8d8885eb
>>>>> Author: Thierry Reding <treding@nvidia.com>
>>>>> Date:   Wed Aug 12 17:00:31 2015 +0200
>>>>>
>>>>>      drm/irq: Make pipe unsigned and name consistent
>>>>>
>>>>> Trigering a warning when trying to sample the vblank timestamp for a
>>>>> non-existing pipe. There's a few ways to fix this:
>>>>>
>>>>> - Open-code the old behaviour, which just enshrines this slight
>>>>>    breakage of the userspace ABI.
>>>>>
>>>>> - Revert Mario's commit and again inflict broken timestamps, again not
>>>>>    pretty.
>>>>>
>>>>> - Fix this for real by delaying the pageflip TS until the next vblank
>>>>>    interrupt, thereby making it accurate.
>>>>>
>>>>> This patch implements the third option. Since having a page flip
>>>>> interrupt that happens when the pageflip gets armed and not when it
>>>>> completes in the next vblank seems to be fairly common (older i915 hw
>>>>> works very similarly) create a new helper to arm vblank events for
>>>>> such drivers.
>>>>>
>>>>> Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=106431
>>>>> Cc: Thierry Reding <treding@nvidia.com>
>>>>> Cc: Mario Kleiner <mario.kleiner.de@gmail.com>
>>>>> Cc: Ben Skeggs <bskeggs@redhat.com>
>>>>> Cc: Ilia Mirkin <imirkin@alum.mit.edu>
>>>>>
>>>>> v2 (mario): Integrate my own review comments into Daniels patch.
>>>>>     - Fix function prototypes in drmP.h
>>>>>     - Add missing vblank_put() for pageflip completion without
>>>>>       pageflip event.
>>>>>     - Initialize sequence number for queued pageflip event to avoidng
>>>>>       trouble in drm_handle_vblank_events().
>>>>>     - Remove dead code and spelling fix.
>>>>>
>>>>> v3 (mario): Add a signed-off-by and cc stable tag per Ilja's advice.
>>>>>
>>>>> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
>>>>> (v1) Reviewed-by: Mario Kleiner <mario.kleiner.de@gmail.com>
>>>>> (v2/v3) Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com>
>>>>>
>>>>> Cc: stable@vger.kernel.org # v4.3
>>>>> ---
>>>>>   drivers/gpu/drm/drm_irq.c                 | 54 ++++++++++++++++++++++++++++++-
>>>>>   drivers/gpu/drm/nouveau/nouveau_display.c | 19 ++++++-----
>>>>>   include/drm/drmP.h                        |  4 +++
>>>>>   3 files changed, 68 insertions(+), 9 deletions(-)
>>>>
>>>> This looks good to me. Let me clean this up a little and submit it to
>>>> Dave.
>>>>
>>>> Thierry
>>>>
>>>
>>> Btw., if somebody has a functional old card for testing this, it should 
>>> be easy to verify if it works on pre-nv50. If it would not work it would 
>>> deliver the pageflip event 1 frame delayed, so at least on standard 
>>> nouveau + default DRI2 + default double-buffering the rate for a tight 
>>> loop of page-flipped swaps should go down to 30 fps on a 60 Hz display, 
>>> quite noticeable. Afaik we also have Piglit tests for OML_sync_control 
>>> which would likely fail if this would be broken.
>>>
>>> Oh and if someone has tips on how to resurrect an old nv-40 PC (booted 
>>> with BIOS only) graphics card in a MacPro (EFI boot), i wouldn't mind 
>>> hearing them. It would be nice to still be able to use that card for 
>>> testing.
>>>
>>> thanks,
>>> -mario
>>
>>
>> ------------[ cut here ]------------
>> WARNING: CPU: 0 PID: 313 at lib/dma-debug.c:1205 check_sync+0x169/0x6e0()
>> nouveau 0000:01:00.0: DMA-API: device driver tries to sync DMA memory it has not allocated [device address=0x00000000c0bf6468] [size=4096 bytes]
>> Modules linked in: nouveau(+) ...
>> CPU: 0 PID: 313 Comm: systemd-udevd Not tainted 4.3.0-3.fc22.i686+debug #1
>> ...
>> Call Trace:
>>  [<c078a28f>] dump_stack+0x48/0x69
>>  [<c0461fc7>] warn_slowpath_common+0x87/0xc0
>>  [<c07b9029>] ? check_sync+0x169/0x6e0
>>  [<c07b9029>] ? check_sync+0x169/0x6e0
>>  [<c046203e>] warn_slowpath_fmt+0x3e/0x60
>>  [<c07b9029>] check_sync+0x169/0x6e0
>>  [<c07b96ad>] debug_dma_sync_single_for_device+0x7d/0x90
>>  [<f7ece298>] ? ttm_bo_del_sub_from_lru+0x18/0x50 [ttm]
>>  [<c040bef0>] ? text_poke_bp+0xd0/0xd0
>>  [<f85d96db>] nouveau_bo_sync_for_device+0x8b/0xa0 [nouveau]
>>  [<f85d97c4>] nouveau_bo_validate+0x34/0x40 [nouveau]
>>  [<f85d9958>] nouveau_bo_pin+0x188/0x290 [nouveau]
>>  [<f85d7fe0>] ? nv10_bo_put_tile_region+0x80/0x80 [nouveau]
>>  [<f85ec7fd>] nouveau_channel_prep+0xfd/0x2c0 [nouveau]
>>  [<f85eca17>] nouveau_channel_new+0x57/0x7a0 [nouveau]
>>  [<c05da57c>] ? kfree+0xdc/0x280
>>  [<f8540082>] ? nvif_object_sclass_put+0x12/0x20 [nouveau]
>>  [<f85d5666>] nouveau_drm_load+0x596/0x8d0 [nouveau]
>>  [<c04bc14c>] ? trace_hardirqs_on_caller+0x12c/0x1d0
>>  [<f7e8bfe9>] ? drm_minor_register+0x89/0x120 [drm]
>>  [<f7e8c116>] drm_dev_register+0x96/0xa0 [drm]
>>  [<f7e8ece9>] drm_get_pci_dev+0x79/0x1c0 [drm]
>>  [<c07d973e>] ? pcibios_set_master+0x4e/0xa0
>>  [<f85d5b8e>] nouveau_drm_probe+0x1ee/0x220 [nouveau]
>>  [<c07dbf3b>] pci_device_probe+0x7b/0xf0
>>  [<c08bf366>] ? devices_kset_move_last+0x56/0xa0
>>  [<c08c2de4>] driver_probe_device+0x204/0x490
>>  [<c08c30bc>] ? __driver_attach+0x4c/0x90
>>  [<c07dbc02>] ? pci_match_device+0xd2/0x100
>>  [<c08c30f1>] __driver_attach+0x81/0x90
>>  [<c08c3070>] ? driver_probe_device+0x490/0x490
>>  [<c08c0b97>] bus_for_each_dev+0x57/0xa0
>>  [<c08c25ce>] driver_attach+0x1e/0x20
>>  [<c08c3070>] ? driver_probe_device+0x490/0x490
>>  [<c08c214f>] bus_add_driver+0x1ef/0x290
>>  [<c08c3bdd>] driver_register+0x5d/0xf0
>>  [<c07da71a>] __pci_register_driver+0x4a/0x50
>>  [<f7e8ef0d>] drm_pci_init+0xdd/0x100 [drm]
>>  [<f7f211f9>] nouveau_drm_init+0x1f9/0x1000 [nouveau]
>>  [<f7f21000>] ? 0xf7f21000
>>  [<c040047a>] do_one_initcall+0xaa/0x200
>>  [<f7f21000>] ? 0xf7f21000
>>  [<c04dae42>] ? rcu_read_lock_sched_held+0x42/0x80
>>  [<c05daf0d>] ? kmem_cache_alloc_trace+0x23d/0x310
>>  [<c0582dd1>] ? do_init_module+0x21/0x1b7
>>  [<c0582dd1>] ? do_init_module+0x21/0x1b7
>>  [<c0582e00>] do_init_module+0x50/0x1b7
>>  [<c05036ec>] load_module+0x1ebc/0x2550
>>  [<c0b993d7>] ? _raw_spin_unlock_irq+0x27/0x40
>>  [<c048e6aa>] ? finish_task_switch+0x8a/0x1d0
>>  [<c0503ec7>] SyS_init_module+0x147/0x1a0
>>  [<c04012c4>] ? do_audit_syscall_entry.isra.9+0x44/0x50
>>  [<c0401627>] ? syscall_trace_enter_phase1+0x107/0x130
>>  [<c0b99f05>] syscall_call+0x7/0x7
>> ---[ end trace d3c14159641a1388 ]---
>>
>>
>> NV34 tested with 4.3.0-3.fc22.i686
>> i.e. 4.3.0-1.fc24.i686 & drm-nouveau-Fix-pre-nv50-pageflip-events-v4.patch
>>
>> http://koji.fedoraproject.org/koji/buildinfo?buildID=695636
>> https://patchwork.kernel.org/patch/7591531/mbox
> 
> This doesn't look at all related and has probably been an issue for
> quite some time. I /think/ this happens because memory is allocated from
> the non-DMA pool (i.e. using alloc_page()) and then ends up getting run
> through the dma_sync_*() API for cache maintenance. But the assumption
> is that you can only do cache maintenance by the dma_sync_*() API on
> memory allocated by dma_alloc_*(), hence the warning.
> 
> There was some discussion about this a while ago, and there was some
> conclusion that an API was needed to do cache maintenance on non-DMA-
> allocated pages of memory, but I don't think any work happened towards
> that API.
> 
> Adding Alex and Arnd who had been part of that discussion, though
> possibly in different threads. Guys, I've been doing too many unrelated
> things lately it seems, because I can't remember where exactly we left
> off. I vaguely remember that at some point somebody (maybe Russell) had
> objected to adding such a non-DMA cache-maintenance API, but I can't
> find a link to the relevant threads.
> 
> Thierry
> 


Mister Thierry, if you make a patch, do not hesitate to share.

Thanks

Ref.
https://bugs.freedesktop.org/attachment.cgi?id=120544
diff mbox

Patch

diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c
index eba6337..819b8c1 100644
--- a/drivers/gpu/drm/drm_irq.c
+++ b/drivers/gpu/drm/drm_irq.c
@@ -972,7 +972,8 @@  static void send_vblank_event(struct drm_device *dev,
 		struct drm_pending_vblank_event *e,
 		unsigned long seq, struct timeval *now)
 {
-	WARN_ON_SMP(!spin_is_locked(&dev->event_lock));
+	assert_spin_locked(&dev->event_lock);
+
 	e->event.sequence = seq;
 	e->event.tv_sec = now->tv_sec;
 	e->event.tv_usec = now->tv_usec;
@@ -985,6 +986,57 @@  static void send_vblank_event(struct drm_device *dev,
 }
 
 /**
+ * drm_arm_vblank_event - arm vblank event after pageflip
+ * @dev: DRM device
+ * @pipe: CRTC index
+ * @e: the event to prepare to send
+ *
+ * A lot of drivers need to generate vblank events for the very next vblank
+ * interrupt. For example when the page flip interrupt happens when the page
+ * flip gets armed, but not when it actually executes within the next vblank
+ * period. This helper function implements exactly the required vblank arming
+ * behaviour.
+ *
+ * Caller must hold event lock. Caller must also hold a vblank reference for the
+ * event @e, which will be dropped when the next vblank arrives.
+ *
+ * This is the legacy version of drm_crtc_arm_vblank_event().
+ */
+void drm_arm_vblank_event(struct drm_device *dev, unsigned int pipe,
+			  struct drm_pending_vblank_event *e)
+{
+	assert_spin_locked(&dev->event_lock);
+
+	e->pipe = pipe;
+	e->event.sequence = drm_vblank_count(dev, pipe);
+	list_add_tail(&e->base.link, &dev->vblank_event_list);
+}
+EXPORT_SYMBOL(drm_arm_vblank_event);
+
+/**
+ * drm_arm_vblank_event - arm vblank event after pageflip
+ * @crtc: the source CRTC of the vblank event
+ * @e: the event to send
+ *
+ * A lot of drivers need to generate vblank events for the very next vblank
+ * interrupt. For example when the page flip interrupt happens when the page
+ * flip gets armed, but not when it actually executes within the next vblank
+ * period. This helper function implements exactly the required vblank arming
+ * behaviour.
+ *
+ * Caller must hold event lock. Caller must also hold a vblank reference for the
+ * event @e, which will be dropped when the next vblank arrives.
+ *
+ * This is the native KMS version of drm_send_vblank_event().
+ */
+void drm_crtc_arm_vblank_event(struct drm_crtc *crtc,
+			       struct drm_pending_vblank_event *e)
+{
+	drm_arm_vblank_event(crtc->dev, drm_crtc_index(crtc), e);
+}
+EXPORT_SYMBOL(drm_crtc_arm_vblank_event);
+
+/**
  * drm_send_vblank_event - helper to send vblank event after pageflip
  * @dev: DRM device
  * @pipe: CRTC index
diff --git a/drivers/gpu/drm/nouveau/nouveau_display.c b/drivers/gpu/drm/nouveau/nouveau_display.c
index db6bc67..64c8d93 100644
--- a/drivers/gpu/drm/nouveau/nouveau_display.c
+++ b/drivers/gpu/drm/nouveau/nouveau_display.c
@@ -829,7 +829,6 @@  nouveau_finish_page_flip(struct nouveau_channel *chan,
 	struct drm_device *dev = drm->dev;
 	struct nouveau_page_flip_state *s;
 	unsigned long flags;
-	int crtcid = -1;
 
 	spin_lock_irqsave(&dev->event_lock, flags);
 
@@ -841,15 +840,19 @@  nouveau_finish_page_flip(struct nouveau_channel *chan,
 
 	s = list_first_entry(&fctx->flip, struct nouveau_page_flip_state, head);
 	if (s->event) {
-		/* Vblank timestamps/counts are only correct on >= NV-50 */
-		if (drm->device.info.family >= NV_DEVICE_INFO_V0_TESLA)
-			crtcid = s->crtc;
+		if (drm->device.info.family < NV_DEVICE_INFO_V0_TESLA) {
+			drm_arm_vblank_event(dev, s->crtc, s->event);
+		} else {
+			drm_send_vblank_event(dev, s->crtc, s->event);
 
-		drm_send_vblank_event(dev, crtcid, s->event);
+			/* Give up ownership of vblank for page-flipped crtc */
+			drm_vblank_put(dev, s->crtc);
+		}
+	}
+	else {
+		/* Give up ownership of vblank for page-flipped crtc */
+		drm_vblank_put(dev, s->crtc);
 	}
-
-	/* Give up ownership of vblank for page-flipped crtc */
-	drm_vblank_put(dev, s->crtc);
 
 	list_del(&s->head);
 	if (ps)
diff --git a/include/drm/drmP.h b/include/drm/drmP.h
index 4d3b842..02a1512 100644
--- a/include/drm/drmP.h
+++ b/include/drm/drmP.h
@@ -948,6 +948,10 @@  extern void drm_send_vblank_event(struct drm_device *dev, unsigned int pipe,
 				  struct drm_pending_vblank_event *e);
 extern void drm_crtc_send_vblank_event(struct drm_crtc *crtc,
 				       struct drm_pending_vblank_event *e);
+extern void drm_arm_vblank_event(struct drm_device *dev, unsigned int pipe,
+				 struct drm_pending_vblank_event *e);
+extern void drm_crtc_arm_vblank_event(struct drm_crtc *crtc,
+				      struct drm_pending_vblank_event *e);
 extern bool drm_handle_vblank(struct drm_device *dev, unsigned int pipe);
 extern bool drm_crtc_handle_vblank(struct drm_crtc *crtc);
 extern int drm_vblank_get(struct drm_device *dev, unsigned int pipe);