| Message ID | 20220119113718.3311-3-Arunpravin.PaneerSelvam@amd.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | None | expand |
On 19/01/2022 11:37, Arunpravin wrote: > On contiguous allocation, we round up the size > to the *next* power of 2, implement a function > to free the unused pages after the newly allocate block. > > v2(Matthew Auld): > - replace function name 'drm_buddy_free_unused_pages' with > drm_buddy_block_trim > - replace input argument name 'actual_size' with 'new_size' > - add more validation checks for input arguments > - add overlaps check to avoid needless searching and splitting > - merged the below patch to see the feature in action > - add free unused pages support to i915 driver > - lock drm_buddy_block_trim() function as it calls mark_free/mark_split > are all globally visible > > v3(Matthew Auld): > - remove trim method error handling as we address the failure case > at drm_buddy_block_trim() function > > v4: > - in case of trim, at __alloc_range() split_block failure path > marks the block as free and removes it from the original list, > potentially also freeing it, to overcome this problem, we turn > the drm_buddy_block_trim() input node into a temporary node to > prevent recursively freeing itself, but still retain the > un-splitting/freeing of the other nodes(Matthew Auld) > > - modify the drm_buddy_block_trim() function return type > > v5(Matthew Auld): > - revert drm_buddy_block_trim() function return type changes in v4 > - modify drm_buddy_block_trim() passing argument n_pages to original_size > as n_pages has already been rounded up to the next power-of-two and > passing n_pages results noop > > v6: > - fix warnings reported by kernel test robot <lkp@intel.com> > > Signed-off-by: Arunpravin <Arunpravin.PaneerSelvam@amd.com> > --- > drivers/gpu/drm/drm_buddy.c | 65 +++++++++++++++++++ > drivers/gpu/drm/i915/i915_ttm_buddy_manager.c | 10 +++ > include/drm/drm_buddy.h | 4 ++ > 3 files changed, 79 insertions(+) > > diff --git a/drivers/gpu/drm/drm_buddy.c b/drivers/gpu/drm/drm_buddy.c > index 6aa5c1ce25bf..c5902a81b8c5 100644 > --- a/drivers/gpu/drm/drm_buddy.c > +++ b/drivers/gpu/drm/drm_buddy.c > @@ -546,6 +546,71 @@ static int __drm_buddy_alloc_range(struct drm_buddy *mm, > return __alloc_range(mm, &dfs, start, size, blocks); > } > > +/** > + * drm_buddy_block_trim - free unused pages > + * > + * @mm: DRM buddy manager > + * @new_size: original size requested > + * @blocks: output list head to add allocated blocks @blocks: Input and output list of allocated blocks. MUST contain single block as input to be trimmed. On success will contain the newly allocated blocks making up the @new_size. Blocks always appear in ascending order. ? > + * > + * For contiguous allocation, we round up the size to the nearest > + * power of two value, drivers consume *actual* size, so remaining > + * portions are unused and it can be freed. so remaining portions are unused and can be optionally freed with this function. ? > + * > + * Returns: > + * 0 on success, error code on failure. > + */ > +int drm_buddy_block_trim(struct drm_buddy *mm, > + u64 new_size, > + struct list_head *blocks) > +{ > + struct drm_buddy_block *parent; > + struct drm_buddy_block *block; > + LIST_HEAD(dfs); > + u64 new_start; > + int err; > + > + if (!list_is_singular(blocks)) > + return -EINVAL; > + > + block = list_first_entry(blocks, > + struct drm_buddy_block, > + link); > + > + if (!drm_buddy_block_is_allocated(block)) Maybe: if (WARN_ON(!drm_buddy_block_is_allocated())) AFAIK it should be normally impossible to be handed such non-allocated block, and so should be treated as a serious programmer error. ? > + return -EINVAL; > + > + if (new_size > drm_buddy_block_size(mm, block)) > + return -EINVAL; > + > + if (!new_size && !IS_ALIGNED(new_size, mm->chunk_size)) > + return -EINVAL; I assume that's a typo: if (!new_size || ...) Otherwise I think looks good. Some unit tests for this would be nice, but not a blocker. And this does at least pass the igt_mock_contiguous selftest, and I didn't see anything nasty when running on DG1, which does make use of TTM_PL_FLAG_CONTIGUOUS, Reviewed-by: Matthew Auld <matthew.auld@intel.com> > + > + if (new_size == drm_buddy_block_size(mm, block)) > + return 0; > + > + list_del(&block->link); > + mark_free(mm, block); > + mm->avail += drm_buddy_block_size(mm, block); > + > + /* Prevent recursively freeing this node */ > + parent = block->parent; > + block->parent = NULL; > + > + new_start = drm_buddy_block_offset(block); > + list_add(&block->tmp_link, &dfs); > + err = __alloc_range(mm, &dfs, new_start, new_size, blocks); > + if (err) { > + mark_allocated(block); > + mm->avail -= drm_buddy_block_size(mm, block); > + list_add(&block->link, blocks); > + } > + > + block->parent = parent; > + return err; > +} > +EXPORT_SYMBOL(drm_buddy_block_trim); > + > /** > * drm_buddy_alloc_blocks - allocate power-of-two blocks > * > diff --git a/drivers/gpu/drm/i915/i915_ttm_buddy_manager.c b/drivers/gpu/drm/i915/i915_ttm_buddy_manager.c > index 3662434b64bb..53eb100688a6 100644 > --- a/drivers/gpu/drm/i915/i915_ttm_buddy_manager.c > +++ b/drivers/gpu/drm/i915/i915_ttm_buddy_manager.c > @@ -97,6 +97,16 @@ static int i915_ttm_buddy_man_alloc(struct ttm_resource_manager *man, > if (unlikely(err)) > goto err_free_blocks; > > + if (place->flags & TTM_PL_FLAG_CONTIGUOUS) { > + u64 original_size = (u64)bman_res->base.num_pages << PAGE_SHIFT; > + > + mutex_lock(&bman->lock); > + drm_buddy_block_trim(mm, > + original_size, > + &bman_res->blocks); > + mutex_unlock(&bman->lock); > + } > + > *res = &bman_res->base; > return 0; > > diff --git a/include/drm/drm_buddy.h b/include/drm/drm_buddy.h > index 424fc443115e..17ca928fce8e 100644 > --- a/include/drm/drm_buddy.h > +++ b/include/drm/drm_buddy.h > @@ -145,6 +145,10 @@ int drm_buddy_alloc_blocks(struct drm_buddy *mm, > struct list_head *blocks, > unsigned long flags); > > +int drm_buddy_block_trim(struct drm_buddy *mm, > + u64 new_size, > + struct list_head *blocks); > + > void drm_buddy_free_block(struct drm_buddy *mm, struct drm_buddy_block *block); > > void drm_buddy_free_list(struct drm_buddy *mm, struct list_head *objects); >
> -----Original Message----- > From: amd-gfx <amd-gfx-bounces@lists.freedesktop.org> On Behalf Of Matthew Auld > Sent: Thursday, January 20, 2022 11:05 PM > To: Paneer Selvam, Arunpravin <Arunpravin.PaneerSelvam@amd.com>; dri-devel@lists.freedesktop.org; intel-gfx@lists.freedesktop.org; amd-gfx@lists.freedesktop.org > Cc: Deucher, Alexander <Alexander.Deucher@amd.com>; tzimmermann@suse.de; jani.nikula@linux.intel.com; Koenig, Christian <Christian.Koenig@amd.com>; daniel@ffwll.ch > Subject: Re: [PATCH v9 4/6] drm: implement a method to free unused pages > > On 19/01/2022 11:37, Arunpravin wrote: >> On contiguous allocation, we round up the size to the *next* power of >> 2, implement a function to free the unused pages after the newly >> allocate block. >> >> v2(Matthew Auld): >> - replace function name 'drm_buddy_free_unused_pages' with >> drm_buddy_block_trim >> - replace input argument name 'actual_size' with 'new_size' >> - add more validation checks for input arguments >> - add overlaps check to avoid needless searching and splitting >> - merged the below patch to see the feature in action >> - add free unused pages support to i915 driver >> - lock drm_buddy_block_trim() function as it calls mark_free/mark_split >> are all globally visible >> >> v3(Matthew Auld): >> - remove trim method error handling as we address the failure case >> at drm_buddy_block_trim() function >> >> v4: >> - in case of trim, at __alloc_range() split_block failure path >> marks the block as free and removes it from the original list, >> potentially also freeing it, to overcome this problem, we turn >> the drm_buddy_block_trim() input node into a temporary node to >> prevent recursively freeing itself, but still retain the >> un-splitting/freeing of the other nodes(Matthew Auld) >> >> - modify the drm_buddy_block_trim() function return type >> >> v5(Matthew Auld): >> - revert drm_buddy_block_trim() function return type changes in v4 >> - modify drm_buddy_block_trim() passing argument n_pages to original_size >> as n_pages has already been rounded up to the next power-of-two and >> passing n_pages results noop >> >> v6: >> - fix warnings reported by kernel test robot <lkp@intel.com> >> >> Signed-off-by: Arunpravin <Arunpravin.PaneerSelvam@amd.com> >> --- >> drivers/gpu/drm/drm_buddy.c | 65 +++++++++++++++++++ >> drivers/gpu/drm/i915/i915_ttm_buddy_manager.c | 10 +++ >> include/drm/drm_buddy.h | 4 ++ >> 3 files changed, 79 insertions(+) >> >> diff --git a/drivers/gpu/drm/drm_buddy.c b/drivers/gpu/drm/drm_buddy.c >> index 6aa5c1ce25bf..c5902a81b8c5 100644 >> --- a/drivers/gpu/drm/drm_buddy.c >> +++ b/drivers/gpu/drm/drm_buddy.c >> @@ -546,6 +546,71 @@ static int __drm_buddy_alloc_range(struct drm_buddy *mm, >> return __alloc_range(mm, &dfs, start, size, blocks); >> } >> >> +/** >> + * drm_buddy_block_trim - free unused pages >> + * >> + * @mm: DRM buddy manager >> + * @new_size: original size requested >> + * @blocks: output list head to add allocated blocks > > @blocks: Input and output list of allocated blocks. MUST contain single block as input to be trimmed. On success will contain the newly allocated blocks making up the @new_size. Blocks always appear in ascending order. > > ? > >> + * >> + * For contiguous allocation, we round up the size to the nearest >> + * power of two value, drivers consume *actual* size, so remaining >> + * portions are unused and it can be freed. > > so remaining portions are unused and can be optionally freed with this function. > > ? > >> + * >> + * Returns: >> + * 0 on success, error code on failure. >> + */ >> +int drm_buddy_block_trim(struct drm_buddy *mm, >> + u64 new_size, >> + struct list_head *blocks) >> +{ >> + struct drm_buddy_block *parent; >> + struct drm_buddy_block *block; >> + LIST_HEAD(dfs); >> + u64 new_start; >> + int err; >> + >> + if (!list_is_singular(blocks)) >> + return -EINVAL; >> + >> + block = list_first_entry(blocks, >> + struct drm_buddy_block, >> + link); >> + >> + if (!drm_buddy_block_is_allocated(block)) > > Maybe: > > if (WARN_ON(!drm_buddy_block_is_allocated())) > > AFAIK it should be normally impossible to be handed such non-allocated block, and so should be treated as a serious programmer error. > > ? > >> + return -EINVAL; >> + >> + if (new_size > drm_buddy_block_size(mm, block)) >> + return -EINVAL; >> + >> + if (!new_size && !IS_ALIGNED(new_size, mm->chunk_size)) >> + return -EINVAL; > > I assume that's a typo: > > if (!new_size || ...) > > Otherwise I think looks good. Some unit tests for this would be nice, but not a blocker. And this does at least pass the igt_mock_contiguous selftest, and I didn't see anything nasty when running on DG1, which does make use of TTM_PL_FLAG_CONTIGUOUS, Good to hear its running on DG1, all changes are added to v10. working on moving i915 buddy selftests into drm selftest folder, I will add a new unit test case for trim function > Reviewed-by: Matthew Auld <matthew.auld@intel.com> > >> + >> + if (new_size == drm_buddy_block_size(mm, block)) >> + return 0; >> + >> + list_del(&block->link); >> + mark_free(mm, block); >> + mm->avail += drm_buddy_block_size(mm, block); >> + >> + /* Prevent recursively freeing this node */ >> + parent = block->parent; >> + block->parent = NULL; >> + >> + new_start = drm_buddy_block_offset(block); >> + list_add(&block->tmp_link, &dfs); >> + err = __alloc_range(mm, &dfs, new_start, new_size, blocks); >> + if (err) { >> + mark_allocated(block); >> + mm->avail -= drm_buddy_block_size(mm, block); >> + list_add(&block->link, blocks); >> + } >> + >> + block->parent = parent; >> + return err; >> +} >> +EXPORT_SYMBOL(drm_buddy_block_trim); >> + >> /** >> * drm_buddy_alloc_blocks - allocate power-of-two blocks >> * >> diff --git a/drivers/gpu/drm/i915/i915_ttm_buddy_manager.c >> b/drivers/gpu/drm/i915/i915_ttm_buddy_manager.c >> index 3662434b64bb..53eb100688a6 100644 >> --- a/drivers/gpu/drm/i915/i915_ttm_buddy_manager.c >> +++ b/drivers/gpu/drm/i915/i915_ttm_buddy_manager.c >> @@ -97,6 +97,16 @@ static int i915_ttm_buddy_man_alloc(struct ttm_resource_manager *man, >> if (unlikely(err)) >> goto err_free_blocks; >> >> + if (place->flags & TTM_PL_FLAG_CONTIGUOUS) { >> + u64 original_size = (u64)bman_res->base.num_pages << PAGE_SHIFT; >> + >> + mutex_lock(&bman->lock); >> + drm_buddy_block_trim(mm, >> + original_size, >> + &bman_res->blocks); >> + mutex_unlock(&bman->lock); >> + } >> + >> *res = &bman_res->base; >> return 0; >> >> diff --git a/include/drm/drm_buddy.h b/include/drm/drm_buddy.h index >> 424fc443115e..17ca928fce8e 100644 >> --- a/include/drm/drm_buddy.h >> +++ b/include/drm/drm_buddy.h >> @@ -145,6 +145,10 @@ int drm_buddy_alloc_blocks(struct drm_buddy *mm, >> struct list_head *blocks, >> unsigned long flags); >> >> +int drm_buddy_block_trim(struct drm_buddy *mm, >> + u64 new_size, >> + struct list_head *blocks); >> + >> void drm_buddy_free_block(struct drm_buddy *mm, struct >> drm_buddy_block *block); >> >> void drm_buddy_free_list(struct drm_buddy *mm, struct list_head >> *objects); >>
diff --git a/drivers/gpu/drm/drm_buddy.c b/drivers/gpu/drm/drm_buddy.c index 6aa5c1ce25bf..c5902a81b8c5 100644 --- a/drivers/gpu/drm/drm_buddy.c +++ b/drivers/gpu/drm/drm_buddy.c @@ -546,6 +546,71 @@ static int __drm_buddy_alloc_range(struct drm_buddy *mm, return __alloc_range(mm, &dfs, start, size, blocks); } +/** + * drm_buddy_block_trim - free unused pages + * + * @mm: DRM buddy manager + * @new_size: original size requested + * @blocks: output list head to add allocated blocks + * + * For contiguous allocation, we round up the size to the nearest + * power of two value, drivers consume *actual* size, so remaining + * portions are unused and it can be freed. + * + * Returns: + * 0 on success, error code on failure. + */ +int drm_buddy_block_trim(struct drm_buddy *mm, + u64 new_size, + struct list_head *blocks) +{ + struct drm_buddy_block *parent; + struct drm_buddy_block *block; + LIST_HEAD(dfs); + u64 new_start; + int err; + + if (!list_is_singular(blocks)) + return -EINVAL; + + block = list_first_entry(blocks, + struct drm_buddy_block, + link); + + if (!drm_buddy_block_is_allocated(block)) + return -EINVAL; + + if (new_size > drm_buddy_block_size(mm, block)) + return -EINVAL; + + if (!new_size && !IS_ALIGNED(new_size, mm->chunk_size)) + return -EINVAL; + + if (new_size == drm_buddy_block_size(mm, block)) + return 0; + + list_del(&block->link); + mark_free(mm, block); + mm->avail += drm_buddy_block_size(mm, block); + + /* Prevent recursively freeing this node */ + parent = block->parent; + block->parent = NULL; + + new_start = drm_buddy_block_offset(block); + list_add(&block->tmp_link, &dfs); + err = __alloc_range(mm, &dfs, new_start, new_size, blocks); + if (err) { + mark_allocated(block); + mm->avail -= drm_buddy_block_size(mm, block); + list_add(&block->link, blocks); + } + + block->parent = parent; + return err; +} +EXPORT_SYMBOL(drm_buddy_block_trim); + /** * drm_buddy_alloc_blocks - allocate power-of-two blocks * diff --git a/drivers/gpu/drm/i915/i915_ttm_buddy_manager.c b/drivers/gpu/drm/i915/i915_ttm_buddy_manager.c index 3662434b64bb..53eb100688a6 100644 --- a/drivers/gpu/drm/i915/i915_ttm_buddy_manager.c +++ b/drivers/gpu/drm/i915/i915_ttm_buddy_manager.c @@ -97,6 +97,16 @@ static int i915_ttm_buddy_man_alloc(struct ttm_resource_manager *man, if (unlikely(err)) goto err_free_blocks; + if (place->flags & TTM_PL_FLAG_CONTIGUOUS) { + u64 original_size = (u64)bman_res->base.num_pages << PAGE_SHIFT; + + mutex_lock(&bman->lock); + drm_buddy_block_trim(mm, + original_size, + &bman_res->blocks); + mutex_unlock(&bman->lock); + } + *res = &bman_res->base; return 0; diff --git a/include/drm/drm_buddy.h b/include/drm/drm_buddy.h index 424fc443115e..17ca928fce8e 100644 --- a/include/drm/drm_buddy.h +++ b/include/drm/drm_buddy.h @@ -145,6 +145,10 @@ int drm_buddy_alloc_blocks(struct drm_buddy *mm, struct list_head *blocks, unsigned long flags); +int drm_buddy_block_trim(struct drm_buddy *mm, + u64 new_size, + struct list_head *blocks); + void drm_buddy_free_block(struct drm_buddy *mm, struct drm_buddy_block *block); void drm_buddy_free_list(struct drm_buddy *mm, struct list_head *objects);
On contiguous allocation, we round up the size to the *next* power of 2, implement a function to free the unused pages after the newly allocate block. v2(Matthew Auld): - replace function name 'drm_buddy_free_unused_pages' with drm_buddy_block_trim - replace input argument name 'actual_size' with 'new_size' - add more validation checks for input arguments - add overlaps check to avoid needless searching and splitting - merged the below patch to see the feature in action - add free unused pages support to i915 driver - lock drm_buddy_block_trim() function as it calls mark_free/mark_split are all globally visible v3(Matthew Auld): - remove trim method error handling as we address the failure case at drm_buddy_block_trim() function v4: - in case of trim, at __alloc_range() split_block failure path marks the block as free and removes it from the original list, potentially also freeing it, to overcome this problem, we turn the drm_buddy_block_trim() input node into a temporary node to prevent recursively freeing itself, but still retain the un-splitting/freeing of the other nodes(Matthew Auld) - modify the drm_buddy_block_trim() function return type v5(Matthew Auld): - revert drm_buddy_block_trim() function return type changes in v4 - modify drm_buddy_block_trim() passing argument n_pages to original_size as n_pages has already been rounded up to the next power-of-two and passing n_pages results noop v6: - fix warnings reported by kernel test robot <lkp@intel.com> Signed-off-by: Arunpravin <Arunpravin.PaneerSelvam@amd.com> --- drivers/gpu/drm/drm_buddy.c | 65 +++++++++++++++++++ drivers/gpu/drm/i915/i915_ttm_buddy_manager.c | 10 +++ include/drm/drm_buddy.h | 4 ++ 3 files changed, 79 insertions(+)