On Mon, Aug 20, 2018 at 09:17:12PM +0800, Christian König wrote:
> Am 20.08.2018 um 08:05 schrieb Huang Rui:
> > On Fri, Aug 17, 2018 at 06:38:16PM +0800, Koenig, Christian wrote:
> >> Am 17.08.2018 um 12:08 schrieb Huang Rui:
> >>> I continue to work for bulk moving that based on the proposal by Christian.
> >>>
> >>> Background:
> >>> amdgpu driver will move all PD/PT and PerVM BOs into idle list. Then move all of
> >>> them on the end of LRU list one by one. Thus, that cause so many BOs moved to
> >>> the end of the LRU, and impact performance seriously.
> >>>
> >>> Then Christian provided a workaround to not move PD/PT BOs on LRU with below
> >>> patch:
> >>> "drm/amdgpu: band aid validating VM PTs"
> >>> Commit 0bbf32026cf5ba41e9922b30e26e1bed1ecd38ae
> >>>
> >>> However, the final solution should bulk move all PD/PT and PerVM BOs on the LRU
> >>> instead of one by one.
> >>>
> >>> Whenever amdgpu_vm_validate_pt_bos() is called and we have BOs which need to be
> >>> validated we move all BOs together to the end of the LRU without dropping the
> >>> lock for the LRU.
> >>>
> >>> While doing so we note the beginning and end of this block in the LRU list.
> >>>
> >>> Now when amdgpu_vm_validate_pt_bos() is called and we don't have anything to do,
> >>> we don't move every BO one by one, but instead cut the LRU list into pieces so
> >>> that we bulk move everything to the end in just one operation.
> >>>
> >>> Test data:
> >>> +--------------+-----------------+-----------+---------------------------------------+
> >>> | |The Talos |Clpeak(OCL)|BusSpeedReadback(OCL) |
> >>> | |Principle(Vulkan)| | |
> >>> +------------------------------------------------------------------------------------+
> >>> | | | |0.319 ms(1k) 0.314 ms(2K) 0.308 ms(4K) |
> >>> | Original | 147.7 FPS | 76.86 us |0.307 ms(8K) 0.310 ms(16K) |
> >>> +------------------------------------------------------------------------------------+
> >>> | Orignial + WA| | |0.254 ms(1K) 0.241 ms(2K) |
> >>> |(don't move | 162.1 FPS | 42.15 us |0.230 ms(4K) 0.223 ms(8K) 0.204 ms(16K)|
> >>> |PT BOs on LRU)| | | |
> >>> +------------------------------------------------------------------------------------+
> >>> | Bulk move | 163.1 FPS | 40.52 us |0.244 ms(1K) 0.252 ms(2K) 0.213 ms(4K) |
> >>> | | | |0.214 ms(8K) 0.225 ms(16K) |
> >>> +--------------+-----------------+-----------+---------------------------------------+
> >>>
> >>> After test them with above three benchmarks include vulkan and opencl. We can
> >>> see the visible improvement than original, and even better than original with
> >>> workaround.
> >>>
> >>> v2: move all BOs include idle, relocated, and moved list to the end of LRU and
> >>> put them together.
> >>> v3: remove unused parameter and use list_for_each_entry instead of the one with
> >>> save entry.
> >>> v4: move the amdgpu_vm_move_to_lru_tail after command submission, at that time,
> >>> all bo will be back on idle list.
> >>>
> >>> Signed-off-by: Christian König <christian.koenig at amd.com>
> >>> Signed-off-by: Huang Rui <ray.huang at amd.com>
> >>> Tested-by: Mike Lothian <mike at fireburn.co.uk>
> >>> Tested-by: Dieter Nützel <Dieter at nuetzel-hh.de>
> >>> Acked-by: Chunming Zhou <david1.zhou at amd.com>
> >>> ---
> >>> drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c | 11 ++++++
> >>> drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c | 71 ++++++++++++++++++++++++++--------
> >>> drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h | 11 +++++-
> >>> 3 files changed, 75 insertions(+), 18 deletions(-)
> >>>
> >>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
> >>> index 502b94f..9fbdf02 100644
> >>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
> >>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
> >>> @@ -1260,6 +1260,16 @@ static int amdgpu_cs_submit(struct amdgpu_cs_parser *p,
> >>> return 0;
> >>> }
> >>>
> >>> +static void amdgpu_cs_vm_move_on_lru(struct amdgpu_device *adev,
> >>> + struct amdgpu_cs_parser *p)
> >>> +{
> >>> + struct amdgpu_fpriv *fpriv = p->filp->driver_priv;
> >>> + struct amdgpu_vm *vm = &fpriv->vm;
> >>> +
> >>> + if (vm->validated)
> >> That check belongs inside amdgpu_vm_move_to_lru_tail().
> >>
> >>> + amdgpu_vm_move_to_lru_tail(adev, vm);
> >>> +}
> >>> +
> >>> int amdgpu_cs_ioctl(struct drm_device *dev, void *data, struct drm_file *filp)
> >>> {
> >>> struct amdgpu_device *adev = dev->dev_private;
> >>> @@ -1310,6 +1320,7 @@ int amdgpu_cs_ioctl(struct drm_device *dev, void *data, struct drm_file *filp)
> >>>
> >>> r = amdgpu_cs_submit(&parser, cs);
> >>>
> >>> + amdgpu_cs_vm_move_on_lru(adev, &parser);
> >>> out:
> >>> amdgpu_cs_parser_fini(&parser, r, reserved_buffers);
> >>> return r;
> >>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
> >>> index 9c84770..037cfbc 100644
> >>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
> >>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
> >>> @@ -268,6 +268,53 @@ void amdgpu_vm_get_pd_bo(struct amdgpu_vm *vm,
> >>> }
> >>>
> >>> /**
> >>> + * amdgpu_vm_move_to_lru_tail_by_list - move one list of BOs to end of LRU
> >>> + *
> >>> + * @vm: vm providing the BOs
> >>> + * @list: the list that stored BOs
> >>> + *
> >>> + * Move one list of BOs to the end of LRU and update the positions.
> >>> + */
> >>> +static void
> >>> +amdgpu_vm_move_to_lru_tail_by_list(struct amdgpu_vm *vm, struct list_head *list)
> >> I don't see much of a point having a separate function for this any more.
> >>
> >>> +{
> >>> + struct amdgpu_vm_bo_base *bo_base;
> >>> +
> >>> + list_for_each_entry(bo_base, list, vm_status) {
> >>> + struct amdgpu_bo *bo = bo_base->bo;
> >>> +
> >>> + if (!bo->parent)
> >>> + continue;
> >>> +
> >>> + ttm_bo_move_to_lru_tail(&bo->tbo, &vm->lru_bulk_move);
> >>> + if (bo->shadow)
> >>> + ttm_bo_move_to_lru_tail(&bo->shadow->tbo,
> >>> + &vm->lru_bulk_move);
> >>> + }
> >>> +}
> >>> +
> >>> +/**
> >>> + * amdgpu_vm_move_to_lru_tail - move all BOs to the end of LRU
> >>> + *
> >>> + * @adev: amdgpu device pointer
> >>> + * @vm: vm providing the BOs
> >>> + *
> >>> + * Move all BOs to the end of LRU and remember their positions to put them
> >>> + * together.
> >>> + */
> >>> +void amdgpu_vm_move_to_lru_tail(struct amdgpu_device *adev,
> >>> + struct amdgpu_vm *vm)
> >>> +{
> >>> + struct ttm_bo_global *glob = adev->mman.bdev.glob;
> >>> +
> >>> + memset(&vm->lru_bulk_move, 0, sizeof(vm->lru_bulk_move));
> >>> +
> >>> + spin_lock(&glob->lru_lock);
> >>> + amdgpu_vm_move_to_lru_tail_by_list(vm, &vm->idle);
> >>> + spin_unlock(&glob->lru_lock);
> >>> +}
> >>> +
> >>> +/**
> >>> * amdgpu_vm_validate_pt_bos - validate the page table BOs
> >>> *
> >>> * @adev: amdgpu device pointer
> >>> @@ -288,6 +335,7 @@ int amdgpu_vm_validate_pt_bos(struct amdgpu_device *adev, struct amdgpu_vm *vm,
> >>> struct amdgpu_vm_bo_base *bo_base, *tmp;
> >>> int r = 0;
> >>>
> >>> + vm->validated = false;
> >> That won't work like this. It is perfectly possible that CS is aborted
> >> because of a signal and amdgpu_vm_move_to_lru_tail() never called.
> >>
> >> I suggest to do "vm->validated |= !list_empty(&vm->evicted);" here and
> >> then set it to false again in amdgpu_vm_move_to_lru_tail().
> >>
> >> And maybe we need a better name than "validated", maybe "bulk_moveable"
> >> or something like that.
> >>
> > Actually, "validated" is opposite to "bulk_moveable".
> > So how about use "vm->bulk_moveable = list_empty(&vm->evicted);" here
>
> That still won't work correct. See the validation can be interrupted.
>
> So we need something like "vm->bulk_moveable &=
> list_empty(&vm->evicted);" here.
Thanks. I found if we use vm->bulk_moveable, it will have a corruption of list.
[ 2763.834228] ------------[ cut here ]------------
[ 2763.839221] list_del corruption. prev->next should be ffff9137dae028f8, but was ffffa59b82003ae0
[ 2763.848330] WARNING: CPU: 1 PID: 281 at lib/list_debug.c:53 __list_del_entry_valid+0x7c/0xa0
...
[ 2764.053257] Call Trace:
[ 2764.055748] ttm_bo_del_from_lru+0x77/0xc0 [ttm]
[ 2764.060437] ttm_bo_release+0x23a/0x2c0 [ttm]
[ 2764.064924] amdgpu_bo_destroy+0x93/0x140 [amdgpu]
[ 2764.069769] ttm_bo_release_list+0x113/0x170 [ttm]
[ 2764.074695] amdgpu_bo_destroy+0x93/0x140 [amdgpu]
[ 2764.079544] ttm_bo_release_list+0x113/0x170 [ttm]
However, if use vm->bulk_not_moveable (like vm->validated), the issue is gone.
I didn't confirm the reason yet.
Thanks,
Ray
>
> Apart from that this now looks really good to me.
>
> Regards,
> Christian.
>
> >
> > Then check the flag after moving the ttm_bo_bulk_move_lru_tail() into
> > amdgpu_vm_move_to_lru_tail() like below:
> >
> > void amdgpu_vm_move_to_lru_tail(struct amdgpu_device *adev,
> > struct amdgpu_vm *vm)
> > {
> > struct ttm_bo_global *glob = adev->mman.bdev.glob;
> > struct amdgpu_vm_bo_base *bo_base;
> >
> > if (vm->bulk_moveable) {
> > spin_lock(&glob->lru_lock);
> > ttm_bo_bulk_move_lru_tail(&vm->lru_bulk_move);
> > spin_unlock(&glob->lru_lock);
> > return;
> > }
> >
> > memset(&vm->lru_bulk_move, 0, sizeof(vm->lru_bulk_move));
> >
> > spin_lock(&glob->lru_lock);
> > list_for_each_entry(bo_base, &vm->idle, vm_status) {
> > struct amdgpu_bo *bo = bo_base->bo;
> >
> > if (!bo->parent)
> > continue;
> >
> > ttm_bo_move_to_lru_tail(&bo->tbo, &vm->lru_bulk_move);
> > if (bo->shadow)
> > ttm_bo_move_to_lru_tail(&bo->shadow->tbo,
> > &vm->lru_bulk_move);
> > }
> > spin_unlock(&glob->lru_lock);
> >
> > vm->bulk_moveable = true;
> > }
> >
> > Thanks,
> > Ray
> >
> >>> list_for_each_entry_safe(bo_base, tmp, &vm->evicted, vm_status) {
> >>> struct amdgpu_bo *bo = bo_base->bo;
> >>>
> >>> @@ -295,14 +343,9 @@ int amdgpu_vm_validate_pt_bos(struct amdgpu_device *adev, struct amdgpu_vm *vm,
> >>> r = validate(param, bo);
> >>> if (r)
> >>> break;
> >>> -
> >>> - spin_lock(&glob->lru_lock);
> >>> - ttm_bo_move_to_lru_tail(&bo->tbo, NULL);
> >>> - if (bo->shadow)
> >>> - ttm_bo_move_to_lru_tail(&bo->shadow->tbo, NULL);
> >>> - spin_unlock(&glob->lru_lock);
> >>> }
> >>>
> >>> + vm->validated = true;
> >>> if (bo->tbo.type != ttm_bo_type_kernel) {
> >>> spin_lock(&vm->moved_lock);
> >>> list_move(&bo_base->vm_status, &vm->moved);
> >>> @@ -312,20 +355,14 @@ int amdgpu_vm_validate_pt_bos(struct amdgpu_device *adev, struct amdgpu_vm *vm,
> >>> }
> >>> }
> >>>
> >>> - spin_lock(&glob->lru_lock);
> >>> - list_for_each_entry(bo_base, &vm->idle, vm_status) {
> >>> - struct amdgpu_bo *bo = bo_base->bo;
> >>> -
> >>> - if (!bo->parent)
> >>> - continue;
> >>> + if (vm->validated)
> >>> + return 0;
> >>>
> >>> - ttm_bo_move_to_lru_tail(&bo->tbo, NULL);
> >>> - if (bo->shadow)
> >>> - ttm_bo_move_to_lru_tail(&bo->shadow->tbo, NULL);
> >>> - }
> >>> + spin_lock(&glob->lru_lock);
> >>> + ttm_bo_bulk_move_lru_tail(&vm->lru_bulk_move);
> >>> spin_unlock(&glob->lru_lock);
> >> Probably best to move that into amdgpu_vm_move_to_lru_tail() as well.
> >>
> >> Regards,
> >> Christian.
> >>
> >>>
> >>> - return r;
> >>> + return 0;
> >>> }
> >>>
> >>> /**
> >>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h
> >>> index 67a15d4..85d57bb 100644
> >>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h
> >>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h
> >>> @@ -29,6 +29,7 @@
> >>> #include <linux/rbtree.h>
> >>> #include <drm/gpu_scheduler.h>
> >>> #include <drm/drm_file.h>
> >>> +#include <drm/ttm/ttm_bo_driver.h>
> >>>
> >>> #include "amdgpu_sync.h"
> >>> #include "amdgpu_ring.h"
> >>> @@ -226,6 +227,11 @@ struct amdgpu_vm {
> >>>
> >>> /* Some basic info about the task */
> >>> struct amdgpu_task_info task_info;
> >>> +
> >>> + /* Store positions of group of BOs */
> >>> + struct ttm_lru_bulk_move lru_bulk_move;
> >>> + /* mark whether has bo validated on evicted list */
> >>> + bool validated;
> >>> };
> >>>
> >>> struct amdgpu_vm_manager {
> >>> @@ -330,8 +336,11 @@ bool amdgpu_vm_need_pipeline_sync(struct amdgpu_ring *ring,
> >>> void amdgpu_vm_check_compute_bug(struct amdgpu_device *adev);
> >>>
> >>> void amdgpu_vm_get_task_info(struct amdgpu_device *adev, unsigned int pasid,
> >>> - struct amdgpu_task_info *task_info);
> >>> + struct amdgpu_task_info *task_info);
> >>>
> >>> void amdgpu_vm_set_task_info(struct amdgpu_vm *vm);
> >>>
> >>> +void amdgpu_vm_move_to_lru_tail(struct amdgpu_device *adev,
> >>> + struct amdgpu_vm *vm);
> >>> +
> >>> #endif
> > _______________________________________________
> > amd-gfx mailing list
> > amd-gfx at lists.freedesktop.org
> > https://lists.freedesktop.org/mailman/listinfo/amd-gfx
>
