| Message ID | 20220202011358.1409946-1-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 | expand |
On 02/02/2022 01:13, 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 efficently 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. > > Suggested-by: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com> > Signed-off-by: Vivek Kasireddy <vivek.kasireddy@intel.com> > --- > drivers/gpu/drm/drm_mm.c | 28 ++++++++++++---------------- > include/drm/drm_mm.h | 32 ++++++++++++++++++++++++++++++++ > 2 files changed, 44 insertions(+), 16 deletions(-) > > diff --git a/drivers/gpu/drm/drm_mm.c b/drivers/gpu/drm/drm_mm.c > index 8257f9d4f619..416c849c10e5 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); May need to add kerneldoc since first/next_hole are now exported, or perhaps double underscore them if DRM core allows that approach to kind of signify "it is exported by shouldn't really be used"? Question for dri-devel I guess. > > /** > * 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); > > @@ -533,13 +534,8 @@ 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_best_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; > diff --git a/include/drm/drm_mm.h b/include/drm/drm_mm.h > index ac33ba1b18bc..5055447697fa 100644 > --- a/include/drm/drm_mm.h > +++ b/include/drm/drm_mm.h > @@ -322,6 +322,17 @@ static inline u64 __drm_mm_hole_node_end(const struct drm_mm_node *hole_node) > return list_next_entry(hole_node, node_list)->start; > } > > +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_hole_node_end - computes the end of the hole following @node > * @hole_node: drm_mm_node which implicitly tracks the following hole > @@ -400,6 +411,27 @@ static inline u64 drm_mm_hole_node_end(const struct drm_mm_node *hole_node) > 1 : 0; \ > pos = list_next_entry(pos, hole_stack)) > > +/** > + * drm_mm_for_each_best_hole - iterator to optimally walk over all holes >= @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 efficently traversing the > + * rbtree associated with @mm. > + */ > +#define drm_mm_for_each_best_hole(pos, mm, range_start, range_end, size, mode) \ Probably should not have "best" in the name since the mode is passed in by the caller. > + for (pos = drm_mm_first_hole(mm, range_start, range_end, size, mode); \ > + pos; \ > + pos = mode & DRM_MM_INSERT_ONCE ? \ > + NULL : drm_mm_next_hole(mm, hole, size, mode)) I think you would need to modify the first/next_hole to mask out DRM_MM_INSERT_ONCE, otherwise it probably does not work as it stands. Regards, Tvrtko > + > /* > * Basic range manager support (drm_mm.c) > */
Hi Tvrtko, > -----Original Message----- > From: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com> > Sent: Wednesday, February 02, 2022 5:04 AM > To: Kasireddy, Vivek <vivek.kasireddy@intel.com>; dri-devel@lists.freedesktop.org > Subject: Re: [PATCH 1/2] drm/mm: Add an iterator to optimally walk over holes for an > allocation > > > On 02/02/2022 01:13, 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 efficently 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. > > > > Suggested-by: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com> > > Signed-off-by: Vivek Kasireddy <vivek.kasireddy@intel.com> > > --- > > drivers/gpu/drm/drm_mm.c | 28 ++++++++++++---------------- > > include/drm/drm_mm.h | 32 ++++++++++++++++++++++++++++++++ > > 2 files changed, 44 insertions(+), 16 deletions(-) > > > > diff --git a/drivers/gpu/drm/drm_mm.c b/drivers/gpu/drm/drm_mm.c > > index 8257f9d4f619..416c849c10e5 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); > > May need to add kerneldoc since first/next_hole are now exported, or > perhaps double underscore them if DRM core allows that approach to kind > of signify "it is exported by shouldn't really be used"? Question for > dri-devel I guess. [Kasireddy, Vivek] Ok, will wait until Daniel or others on dri-devel weigh in. However, it looks like double underscore is the way to go given how the exported symbol __drm_mm_interval_first() is used. > > > > > /** > > * 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); > > > > @@ -533,13 +534,8 @@ 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_best_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; > > diff --git a/include/drm/drm_mm.h b/include/drm/drm_mm.h > > index ac33ba1b18bc..5055447697fa 100644 > > --- a/include/drm/drm_mm.h > > +++ b/include/drm/drm_mm.h > > @@ -322,6 +322,17 @@ static inline u64 __drm_mm_hole_node_end(const struct > drm_mm_node *hole_node) > > return list_next_entry(hole_node, node_list)->start; > > } > > > > +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_hole_node_end - computes the end of the hole following @node > > * @hole_node: drm_mm_node which implicitly tracks the following hole > > @@ -400,6 +411,27 @@ static inline u64 drm_mm_hole_node_end(const struct > drm_mm_node *hole_node) > > 1 : 0; \ > > pos = list_next_entry(pos, hole_stack)) > > > > +/** > > + * drm_mm_for_each_best_hole - iterator to optimally walk over all holes >= @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 efficently traversing the > > + * rbtree associated with @mm. > > + */ > > +#define drm_mm_for_each_best_hole(pos, mm, range_start, range_end, size, mode) \ > > Probably should not have "best" in the name since the mode is passed in > by the caller. [Kasireddy, Vivek] How about drm_mm_for_each_suitable_hole(...)? > > > + for (pos = drm_mm_first_hole(mm, range_start, range_end, size, mode); \ > > + pos; \ > > + pos = mode & DRM_MM_INSERT_ONCE ? \ > > + NULL : drm_mm_next_hole(mm, hole, size, mode)) > > I think you would need to modify the first/next_hole to mask out > DRM_MM_INSERT_ONCE, otherwise it probably does not work as it stands. [Kasireddy, Vivek] Either that or I do the mask out in the macro itself: #define drm_mm_for_each_best_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)) and also take care of the locations where mode is checked in the loop. Or, I could just retain the once bool and pass it to the macro. Not sure if this is ok but there don't seem to be cleaner/elegant options. Thanks, Vivek > > Regards, > > Tvrtko > > > + > > /* > > * Basic range manager support (drm_mm.c) > > */
diff --git a/drivers/gpu/drm/drm_mm.c b/drivers/gpu/drm/drm_mm.c index 8257f9d4f619..416c849c10e5 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); @@ -533,13 +534,8 @@ 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_best_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; diff --git a/include/drm/drm_mm.h b/include/drm/drm_mm.h index ac33ba1b18bc..5055447697fa 100644 --- a/include/drm/drm_mm.h +++ b/include/drm/drm_mm.h @@ -322,6 +322,17 @@ static inline u64 __drm_mm_hole_node_end(const struct drm_mm_node *hole_node) return list_next_entry(hole_node, node_list)->start; } +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_hole_node_end - computes the end of the hole following @node * @hole_node: drm_mm_node which implicitly tracks the following hole @@ -400,6 +411,27 @@ static inline u64 drm_mm_hole_node_end(const struct drm_mm_node *hole_node) 1 : 0; \ pos = list_next_entry(pos, hole_stack)) +/** + * drm_mm_for_each_best_hole - iterator to optimally walk over all holes >= @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 efficently traversing the + * rbtree associated with @mm. + */ +#define drm_mm_for_each_best_hole(pos, mm, range_start, range_end, size, mode) \ + for (pos = drm_mm_first_hole(mm, range_start, range_end, size, mode); \ + pos; \ + pos = mode & DRM_MM_INSERT_ONCE ? \ + NULL : drm_mm_next_hole(mm, hole, size, mode)) + /* * 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 efficently 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. Suggested-by: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com> Signed-off-by: Vivek Kasireddy <vivek.kasireddy@intel.com> --- drivers/gpu/drm/drm_mm.c | 28 ++++++++++++---------------- include/drm/drm_mm.h | 32 ++++++++++++++++++++++++++++++++ 2 files changed, 44 insertions(+), 16 deletions(-)