| Message ID | 20220204011939.1517070-1-vivek.kasireddy@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/2] drm/mm: Add an iterator to optimally walk over holes for an allocation (v2) | expand |
On 04/02/2022 01:19, Vivek Kasireddy wrote: > This iterator relies on drm_mm_first_hole() and drm_mm_next_hole() > functions to identify suitable holes for an allocation of a given > size by efficiently traversing the rbtree associated with the given > allocator. > > It replaces the for loop in drm_mm_insert_node_in_range() and can > also be used by drm drivers to quickly identify holes of a certain > size within a given range. > > v2: (Tvrtko) > - Prepend a double underscore for the newly exported first/next_hole > - s/each_best_hole/each_suitable_hole/g > - Mask out DRM_MM_INSERT_ONCE from the mode before calling > first/next_hole and elsewhere. > > Suggested-by: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com> > Signed-off-by: Vivek Kasireddy <vivek.kasireddy@intel.com> > --- > drivers/gpu/drm/drm_mm.c | 38 ++++++++++++++++++-------------------- > include/drm/drm_mm.h | 36 ++++++++++++++++++++++++++++++++++++ > 2 files changed, 54 insertions(+), 20 deletions(-) > > diff --git a/drivers/gpu/drm/drm_mm.c b/drivers/gpu/drm/drm_mm.c > index 8257f9d4f619..b6da1dffcfcb 100644 > --- a/drivers/gpu/drm/drm_mm.c > +++ b/drivers/gpu/drm/drm_mm.c > @@ -352,10 +352,10 @@ static struct drm_mm_node *find_hole_addr(struct drm_mm *mm, u64 addr, u64 size) > return node; > } > > -static struct drm_mm_node * > -first_hole(struct drm_mm *mm, > - u64 start, u64 end, u64 size, > - enum drm_mm_insert_mode mode) > +struct drm_mm_node * > +__drm_mm_first_hole(struct drm_mm *mm, > + u64 start, u64 end, u64 size, > + enum drm_mm_insert_mode mode) > { > switch (mode) { > default: > @@ -374,6 +374,7 @@ first_hole(struct drm_mm *mm, > hole_stack); > } > } > +EXPORT_SYMBOL(__drm_mm_first_hole); > > /** > * DECLARE_NEXT_HOLE_ADDR - macro to declare next hole functions > @@ -410,11 +411,11 @@ static struct drm_mm_node *name(struct drm_mm_node *entry, u64 size) \ > DECLARE_NEXT_HOLE_ADDR(next_hole_high_addr, rb_left, rb_right) > DECLARE_NEXT_HOLE_ADDR(next_hole_low_addr, rb_right, rb_left) > > -static struct drm_mm_node * > -next_hole(struct drm_mm *mm, > - struct drm_mm_node *node, > - u64 size, > - enum drm_mm_insert_mode mode) > +struct drm_mm_node * > +__drm_mm_next_hole(struct drm_mm *mm, > + struct drm_mm_node *node, > + u64 size, > + enum drm_mm_insert_mode mode) > { > switch (mode) { > default: > @@ -432,6 +433,7 @@ next_hole(struct drm_mm *mm, > return &node->hole_stack == &mm->hole_stack ? NULL : node; > } > } > +EXPORT_SYMBOL(__drm_mm_next_hole); > > /** > * drm_mm_reserve_node - insert an pre-initialized node > @@ -520,7 +522,6 @@ int drm_mm_insert_node_in_range(struct drm_mm * const mm, > { > struct drm_mm_node *hole; > u64 remainder_mask; > - bool once; > > DRM_MM_BUG_ON(range_start > range_end); > > @@ -533,22 +534,19 @@ int drm_mm_insert_node_in_range(struct drm_mm * const mm, > if (alignment <= 1) > alignment = 0; > > - once = mode & DRM_MM_INSERT_ONCE; > - mode &= ~DRM_MM_INSERT_ONCE; > - > remainder_mask = is_power_of_2(alignment) ? alignment - 1 : 0; > - for (hole = first_hole(mm, range_start, range_end, size, mode); > - hole; > - hole = once ? NULL : next_hole(mm, hole, size, mode)) { > + drm_mm_for_each_suitable_hole(hole, mm, range_start, range_end, > + size, mode) { > u64 hole_start = __drm_mm_hole_node_start(hole); > u64 hole_end = hole_start + hole->hole_size; > u64 adj_start, adj_end; > u64 col_start, col_end; > + enum drm_mm_insert_mode placement = mode & ~DRM_MM_INSERT_ONCE; Could move outside the loop, but not sure if it matters much. Could also call the masked out variable mode and the passed in one caller_mode, or something, and that way have a smaller diff. (Four following hunks wouldn't be there.) > > - if (mode == DRM_MM_INSERT_LOW && hole_start >= range_end) > + if (placement == DRM_MM_INSERT_LOW && hole_start >= range_end) > break; > > - if (mode == DRM_MM_INSERT_HIGH && hole_end <= range_start) > + if (placement == DRM_MM_INSERT_HIGH && hole_end <= range_start) > break; > > col_start = hole_start; > @@ -562,7 +560,7 @@ int drm_mm_insert_node_in_range(struct drm_mm * const mm, > if (adj_end <= adj_start || adj_end - adj_start < size) > continue; > > - if (mode == DRM_MM_INSERT_HIGH) > + if (placement == DRM_MM_INSERT_HIGH) > adj_start = adj_end - size; > > if (alignment) { > @@ -574,7 +572,7 @@ int drm_mm_insert_node_in_range(struct drm_mm * const mm, > div64_u64_rem(adj_start, alignment, &rem); > if (rem) { > adj_start -= rem; > - if (mode != DRM_MM_INSERT_HIGH) > + if (placement != DRM_MM_INSERT_HIGH) > adj_start += alignment; > > if (adj_start < max(col_start, range_start) || > diff --git a/include/drm/drm_mm.h b/include/drm/drm_mm.h > index ac33ba1b18bc..777f659f9692 100644 > --- a/include/drm/drm_mm.h > +++ b/include/drm/drm_mm.h > @@ -400,6 +400,42 @@ static inline u64 drm_mm_hole_node_end(const struct drm_mm_node *hole_node) > 1 : 0; \ > pos = list_next_entry(pos, hole_stack)) > > +struct drm_mm_node * > +__drm_mm_first_hole(struct drm_mm *mm, > + u64 start, u64 end, u64 size, > + enum drm_mm_insert_mode mode); > + > +struct drm_mm_node * > +__drm_mm_next_hole(struct drm_mm *mm, > + struct drm_mm_node *node, > + u64 size, > + enum drm_mm_insert_mode mode); > + > +/** > + * drm_mm_for_each_suitable_hole - iterator to optimally walk over all > + * holes that can fit an allocation of the given @size. > + * @pos: &drm_mm_node used internally to track progress > + * @mm: &drm_mm allocator to walk > + * @range_start: start of the allowed range for the allocation > + * @range_end: end of the allowed range for the allocation > + * @size: size of the allocation > + * @mode: fine-tune the allocation search > + * > + * This iterator walks over all holes suitable for the allocation of given > + * @size in a very efficient manner. It is implemented by calling > + * drm_mm_first_hole() and drm_mm_next_hole() which identify the > + * appropriate holes within the given range by efficiently traversing the > + * rbtree associated with @mm. > + */ > +#define drm_mm_for_each_suitable_hole(pos, mm, range_start, range_end, \ > + size, mode) \ > + for (pos = __drm_mm_first_hole(mm, range_start, range_end, size, \ > + mode & ~DRM_MM_INSERT_ONCE); \ > + pos; \ > + pos = mode & DRM_MM_INSERT_ONCE ? \ > + NULL : __drm_mm_next_hole(mm, hole, size, \ > + mode & ~DRM_MM_INSERT_ONCE)) > + > /* > * Basic range manager support (drm_mm.c) > */ Nitpicks/bikesheds or not, patch LGTM. Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Adding Christian and Das to Cc, by the virtue of being last people active in the hole area (!). :) Regards, Tvrtko
diff --git a/drivers/gpu/drm/drm_mm.c b/drivers/gpu/drm/drm_mm.c index 8257f9d4f619..b6da1dffcfcb 100644 --- a/drivers/gpu/drm/drm_mm.c +++ b/drivers/gpu/drm/drm_mm.c @@ -352,10 +352,10 @@ static struct drm_mm_node *find_hole_addr(struct drm_mm *mm, u64 addr, u64 size) return node; } -static struct drm_mm_node * -first_hole(struct drm_mm *mm, - u64 start, u64 end, u64 size, - enum drm_mm_insert_mode mode) +struct drm_mm_node * +__drm_mm_first_hole(struct drm_mm *mm, + u64 start, u64 end, u64 size, + enum drm_mm_insert_mode mode) { switch (mode) { default: @@ -374,6 +374,7 @@ first_hole(struct drm_mm *mm, hole_stack); } } +EXPORT_SYMBOL(__drm_mm_first_hole); /** * DECLARE_NEXT_HOLE_ADDR - macro to declare next hole functions @@ -410,11 +411,11 @@ static struct drm_mm_node *name(struct drm_mm_node *entry, u64 size) \ DECLARE_NEXT_HOLE_ADDR(next_hole_high_addr, rb_left, rb_right) DECLARE_NEXT_HOLE_ADDR(next_hole_low_addr, rb_right, rb_left) -static struct drm_mm_node * -next_hole(struct drm_mm *mm, - struct drm_mm_node *node, - u64 size, - enum drm_mm_insert_mode mode) +struct drm_mm_node * +__drm_mm_next_hole(struct drm_mm *mm, + struct drm_mm_node *node, + u64 size, + enum drm_mm_insert_mode mode) { switch (mode) { default: @@ -432,6 +433,7 @@ next_hole(struct drm_mm *mm, return &node->hole_stack == &mm->hole_stack ? NULL : node; } } +EXPORT_SYMBOL(__drm_mm_next_hole); /** * drm_mm_reserve_node - insert an pre-initialized node @@ -520,7 +522,6 @@ int drm_mm_insert_node_in_range(struct drm_mm * const mm, { struct drm_mm_node *hole; u64 remainder_mask; - bool once; DRM_MM_BUG_ON(range_start > range_end); @@ -533,22 +534,19 @@ int drm_mm_insert_node_in_range(struct drm_mm * const mm, if (alignment <= 1) alignment = 0; - once = mode & DRM_MM_INSERT_ONCE; - mode &= ~DRM_MM_INSERT_ONCE; - remainder_mask = is_power_of_2(alignment) ? alignment - 1 : 0; - for (hole = first_hole(mm, range_start, range_end, size, mode); - hole; - hole = once ? NULL : next_hole(mm, hole, size, mode)) { + drm_mm_for_each_suitable_hole(hole, mm, range_start, range_end, + size, mode) { u64 hole_start = __drm_mm_hole_node_start(hole); u64 hole_end = hole_start + hole->hole_size; u64 adj_start, adj_end; u64 col_start, col_end; + enum drm_mm_insert_mode placement = mode & ~DRM_MM_INSERT_ONCE; - if (mode == DRM_MM_INSERT_LOW && hole_start >= range_end) + if (placement == DRM_MM_INSERT_LOW && hole_start >= range_end) break; - if (mode == DRM_MM_INSERT_HIGH && hole_end <= range_start) + if (placement == DRM_MM_INSERT_HIGH && hole_end <= range_start) break; col_start = hole_start; @@ -562,7 +560,7 @@ int drm_mm_insert_node_in_range(struct drm_mm * const mm, if (adj_end <= adj_start || adj_end - adj_start < size) continue; - if (mode == DRM_MM_INSERT_HIGH) + if (placement == DRM_MM_INSERT_HIGH) adj_start = adj_end - size; if (alignment) { @@ -574,7 +572,7 @@ int drm_mm_insert_node_in_range(struct drm_mm * const mm, div64_u64_rem(adj_start, alignment, &rem); if (rem) { adj_start -= rem; - if (mode != DRM_MM_INSERT_HIGH) + if (placement != DRM_MM_INSERT_HIGH) adj_start += alignment; if (adj_start < max(col_start, range_start) || diff --git a/include/drm/drm_mm.h b/include/drm/drm_mm.h index ac33ba1b18bc..777f659f9692 100644 --- a/include/drm/drm_mm.h +++ b/include/drm/drm_mm.h @@ -400,6 +400,42 @@ static inline u64 drm_mm_hole_node_end(const struct drm_mm_node *hole_node) 1 : 0; \ pos = list_next_entry(pos, hole_stack)) +struct drm_mm_node * +__drm_mm_first_hole(struct drm_mm *mm, + u64 start, u64 end, u64 size, + enum drm_mm_insert_mode mode); + +struct drm_mm_node * +__drm_mm_next_hole(struct drm_mm *mm, + struct drm_mm_node *node, + u64 size, + enum drm_mm_insert_mode mode); + +/** + * drm_mm_for_each_suitable_hole - iterator to optimally walk over all + * holes that can fit an allocation of the given @size. + * @pos: &drm_mm_node used internally to track progress + * @mm: &drm_mm allocator to walk + * @range_start: start of the allowed range for the allocation + * @range_end: end of the allowed range for the allocation + * @size: size of the allocation + * @mode: fine-tune the allocation search + * + * This iterator walks over all holes suitable for the allocation of given + * @size in a very efficient manner. It is implemented by calling + * drm_mm_first_hole() and drm_mm_next_hole() which identify the + * appropriate holes within the given range by efficiently traversing the + * rbtree associated with @mm. + */ +#define drm_mm_for_each_suitable_hole(pos, mm, range_start, range_end, \ + size, mode) \ + for (pos = __drm_mm_first_hole(mm, range_start, range_end, size, \ + mode & ~DRM_MM_INSERT_ONCE); \ + pos; \ + pos = mode & DRM_MM_INSERT_ONCE ? \ + NULL : __drm_mm_next_hole(mm, hole, size, \ + mode & ~DRM_MM_INSERT_ONCE)) + /* * Basic range manager support (drm_mm.c) */
This iterator relies on drm_mm_first_hole() and drm_mm_next_hole() functions to identify suitable holes for an allocation of a given size by efficiently traversing the rbtree associated with the given allocator. It replaces the for loop in drm_mm_insert_node_in_range() and can also be used by drm drivers to quickly identify holes of a certain size within a given range. v2: (Tvrtko) - Prepend a double underscore for the newly exported first/next_hole - s/each_best_hole/each_suitable_hole/g - Mask out DRM_MM_INSERT_ONCE from the mode before calling first/next_hole and elsewhere. Suggested-by: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com> Signed-off-by: Vivek Kasireddy <vivek.kasireddy@intel.com> --- drivers/gpu/drm/drm_mm.c | 38 ++++++++++++++++++-------------------- include/drm/drm_mm.h | 36 ++++++++++++++++++++++++++++++++++++ 2 files changed, 54 insertions(+), 20 deletions(-)