Avoid clobbering adjacent blocks if they happen to expire earlier and amalgamate together to form the requested hole.
In passing this fixes a regression from commit ea7b1dd44867e9cd6bac67e7c9fc3f128b5b255c Author: Daniel Vetter daniel.vetter@ffwll.ch Date: Fri Feb 18 17:59:12 2011 +0100
drm: mm: track free areas implicitly
which swaps the end address for size (with a potential overflow) and effectively causes the eviction code to clobber almost all earlier buffers above the evictee.
Signed-off-by: Chris Wilson chris@chris-wilson.co.uk Cc: Daniel Vetter daniel.vetter@ffwll.ch --- drivers/gpu/drm/drm_mm.c | 58 +++++++++++++++++++++++++--------------------- include/drm/drm_mm.h | 2 +- 2 files changed, 33 insertions(+), 27 deletions(-)
diff --git a/drivers/gpu/drm/drm_mm.c b/drivers/gpu/drm/drm_mm.c index 7103aa3..c93729c 100644 --- a/drivers/gpu/drm/drm_mm.c +++ b/drivers/gpu/drm/drm_mm.c @@ -421,6 +421,25 @@ static int check_free_hole(unsigned long start, unsigned long end, return end >= start + size; }
+static int adjust_free_hole(unsigned long *start, unsigned long *end, + unsigned long size, unsigned alignment) +{ + if (*end - *start < size) + return 0; + + if (alignment) { + unsigned tmp = *start % alignment; + if (tmp) + *start += alignment - tmp; + } + + if (*end - *start < size) + return 0; + + *end = *start + size; + return 1; +} + struct drm_mm_node *drm_mm_search_free_generic(const struct drm_mm *mm, unsigned long size, unsigned alignment, @@ -545,7 +564,7 @@ void drm_mm_init_scan(struct drm_mm *mm, mm->scan_size = size; mm->scanned_blocks = 0; mm->scan_hit_start = 0; - mm->scan_hit_size = 0; + mm->scan_hit_end = 0; mm->scan_check_range = 0; mm->prev_scanned_node = NULL; } @@ -572,7 +591,7 @@ void drm_mm_init_scan_with_range(struct drm_mm *mm, mm->scan_size = size; mm->scanned_blocks = 0; mm->scan_hit_start = 0; - mm->scan_hit_size = 0; + mm->scan_hit_end = 0; mm->scan_start = start; mm->scan_end = end; mm->scan_check_range = 1; @@ -591,8 +610,6 @@ int drm_mm_scan_add_block(struct drm_mm_node *node) struct drm_mm *mm = node->mm; struct drm_mm_node *prev_node; unsigned long hole_start, hole_end; - unsigned long adj_start; - unsigned long adj_end;
mm->scanned_blocks++;
@@ -612,24 +629,21 @@ int drm_mm_scan_add_block(struct drm_mm_node *node) hole_start = drm_mm_hole_node_start(prev_node); hole_end = drm_mm_hole_node_end(prev_node);
- adj_start = hole_start; - adj_end = hole_end; - if (mm->color_adjust) - mm->color_adjust(prev_node, mm->scan_color, &adj_start, &adj_end); + mm->color_adjust(prev_node, mm->scan_color, + &hole_start, &hole_end);
if (mm->scan_check_range) { - if (adj_start < mm->scan_start) - adj_start = mm->scan_start; - if (adj_end > mm->scan_end) - adj_end = mm->scan_end; + if (hole_start < mm->scan_start) + hole_start = mm->scan_start; + if (hole_end > mm->scan_end) + hole_end = mm->scan_end; }
- if (check_free_hole(adj_start, adj_end, - mm->scan_size, mm->scan_alignment)) { + if (adjust_free_hole(&hole_start, &hole_end, + mm->scan_size, mm->scan_alignment)) { mm->scan_hit_start = hole_start; - mm->scan_hit_size = hole_end; - + mm->scan_hit_end = hole_end; return 1; }
@@ -668,16 +682,8 @@ int drm_mm_scan_remove_block(struct drm_mm_node *node) INIT_LIST_HEAD(&node->node_list); list_add(&node->node_list, &prev_node->node_list);
- /* Only need to check for containement because start&size for the - * complete resulting free block (not just the desired part) is - * stored. */ - if (node->start >= mm->scan_hit_start && - node->start + node->size - <= mm->scan_hit_start + mm->scan_hit_size) { - return 1; - } - - return 0; + return (node->start + node->size >= mm->scan_hit_start && + node->start <= mm->scan_hit_end); } EXPORT_SYMBOL(drm_mm_scan_remove_block);
diff --git a/include/drm/drm_mm.h b/include/drm/drm_mm.h index 9a08a45..9e06ca1 100644 --- a/include/drm/drm_mm.h +++ b/include/drm/drm_mm.h @@ -70,7 +70,7 @@ struct drm_mm { unsigned long scan_color; unsigned long scan_size; unsigned long scan_hit_start; - unsigned scan_hit_size; + unsigned long scan_hit_end; unsigned scanned_blocks; unsigned long scan_start; unsigned long scan_end;
On Sun, 16 Dec 2012 17:51:41 +0000, Chris Wilson chris@chris-wilson.co.uk wrote:
Avoid clobbering adjacent blocks if they happen to expire earlier and amalgamate together to form the requested hole.
In passing this fixes a regression from commit ea7b1dd44867e9cd6bac67e7c9fc3f128b5b255c Author: Daniel Vetter daniel.vetter@ffwll.ch Date: Fri Feb 18 17:59:12 2011 +0100
drm: mm: track free areas implicitly
which swaps the end address for size (with a potential overflow) and effectively causes the eviction code to clobber almost all earlier buffers above the evictee.
Signed-off-by: Chris Wilson chris@chris-wilson.co.uk Cc: Daniel Vetter daniel.vetter@ffwll.ch
On IRC I mentioned that I feared there be dragon lurking here. They turned out to be figments of my own code - a later patch to adjust the allocation of nodes was incomplete.
Please review and consider this patch. -Chris
Avoid clobbering adjacent blocks if they happen to expire earlier and amalgamate together to form the requested hole.
In passing this fixes a regression from commit ea7b1dd44867e9cd6bac67e7c9fc3f128b5b255c Author: Daniel Vetter daniel.vetter@ffwll.ch Date: Fri Feb 18 17:59:12 2011 +0100
drm: mm: track free areas implicitly
which swaps the end address for size (with a potential overflow) and effectively causes the eviction code to clobber almost all earlier buffers above the evictee.
v2: Check the original hole not the adjusted as the coloring may confuse us when later searching for the overlapping nodes. Also make sure that we do apply the range restriction and color adjustment in the same order for both scanning, searching and insertion.
Signed-off-by: Chris Wilson chris@chris-wilson.co.uk Cc: Daniel Vetter daniel.vetter@ffwll.ch --- drivers/gpu/drm/drm_mm.c | 45 +++++++++++++++++---------------------------- include/drm/drm_mm.h | 2 +- 2 files changed, 18 insertions(+), 29 deletions(-)
diff --git a/drivers/gpu/drm/drm_mm.c b/drivers/gpu/drm/drm_mm.c index b751b8e..5847669 100644 --- a/drivers/gpu/drm/drm_mm.c +++ b/drivers/gpu/drm/drm_mm.c @@ -244,11 +244,13 @@ static void drm_mm_insert_helper_range(struct drm_mm_node *hole_node,
BUG_ON(!hole_node->hole_follows || node->allocated);
- if (mm->color_adjust) - mm->color_adjust(hole_node, color, &adj_start, &adj_end); - if (adj_start < start) adj_start = start; + if (adj_end > end) + adj_end = end; + + if (mm->color_adjust) + mm->color_adjust(hole_node, color, &adj_start, &adj_end);
if (alignment) { unsigned tmp = adj_start % alignment; @@ -519,7 +521,7 @@ void drm_mm_init_scan(struct drm_mm *mm, mm->scan_size = size; mm->scanned_blocks = 0; mm->scan_hit_start = 0; - mm->scan_hit_size = 0; + mm->scan_hit_end = 0; mm->scan_check_range = 0; mm->prev_scanned_node = NULL; } @@ -546,7 +548,7 @@ void drm_mm_init_scan_with_range(struct drm_mm *mm, mm->scan_size = size; mm->scanned_blocks = 0; mm->scan_hit_start = 0; - mm->scan_hit_size = 0; + mm->scan_hit_end = 0; mm->scan_start = start; mm->scan_end = end; mm->scan_check_range = 1; @@ -565,8 +567,7 @@ int drm_mm_scan_add_block(struct drm_mm_node *node) struct drm_mm *mm = node->mm; struct drm_mm_node *prev_node; unsigned long hole_start, hole_end; - unsigned long adj_start; - unsigned long adj_end; + unsigned long adj_start, adj_end;
mm->scanned_blocks++;
@@ -583,14 +584,8 @@ int drm_mm_scan_add_block(struct drm_mm_node *node) node->node_list.next = &mm->prev_scanned_node->node_list; mm->prev_scanned_node = node;
- hole_start = drm_mm_hole_node_start(prev_node); - hole_end = drm_mm_hole_node_end(prev_node); - - adj_start = hole_start; - adj_end = hole_end; - - if (mm->color_adjust) - mm->color_adjust(prev_node, mm->scan_color, &adj_start, &adj_end); + adj_start = hole_start = drm_mm_hole_node_start(prev_node); + adji_end = hole_end = drm_mm_hole_node_end(prev_node);
if (mm->scan_check_range) { if (adj_start < mm->scan_start) @@ -599,11 +594,14 @@ int drm_mm_scan_add_block(struct drm_mm_node *node) adj_end = mm->scan_end; }
+ if (mm->color_adjust) + mm->color_adjust(prev_node, mm->scan_color, + adj_start, adj_end); + if (check_free_hole(adj_start, adj_end, mm->scan_size, mm->scan_alignment)) { mm->scan_hit_start = hole_start; - mm->scan_hit_size = hole_end; - + mm->scan_hit_end = hole_end; return 1; }
@@ -639,19 +637,10 @@ int drm_mm_scan_remove_block(struct drm_mm_node *node) node_list);
prev_node->hole_follows = node->scanned_preceeds_hole; - INIT_LIST_HEAD(&node->node_list); list_add(&node->node_list, &prev_node->node_list);
- /* Only need to check for containement because start&size for the - * complete resulting free block (not just the desired part) is - * stored. */ - if (node->start >= mm->scan_hit_start && - node->start + node->size - <= mm->scan_hit_start + mm->scan_hit_size) { - return 1; - } - - return 0; + return (__drm_mm_hole_node_end(node) > mm->scan_hit_start && + node->start < mm->scan_hit_end); } EXPORT_SYMBOL(drm_mm_scan_remove_block);
diff --git a/include/drm/drm_mm.h b/include/drm/drm_mm.h index cd45365..58b8979 100644 --- a/include/drm/drm_mm.h +++ b/include/drm/drm_mm.h @@ -70,7 +70,7 @@ struct drm_mm { unsigned long scan_color; unsigned long scan_size; unsigned long scan_hit_start; - unsigned scan_hit_size; + unsigned long scan_hit_end; unsigned scanned_blocks; unsigned long scan_start; unsigned long scan_end;
Avoid clobbering adjacent blocks if they happen to expire earlier and amalgamate together to form the requested hole.
In passing this fixes a regression from commit ea7b1dd44867e9cd6bac67e7c9fc3f128b5b255c Author: Daniel Vetter daniel.vetter@ffwll.ch Date: Fri Feb 18 17:59:12 2011 +0100
drm: mm: track free areas implicitly
which swaps the end address for size (with a potential overflow) and effectively causes the eviction code to clobber almost all earlier buffers above the evictee.
v2: Check the original hole not the adjusted as the coloring may confuse us when later searching for the overlapping nodes. Also make sure that we do apply the range restriction and color adjustment in the same order for both scanning, searching and insertion.
v3: Send the version that was actually tested.
Signed-off-by: Chris Wilson chris@chris-wilson.co.uk Cc: Daniel Vetter daniel.vetter@ffwll.ch --- drivers/gpu/drm/drm_mm.c | 45 +++++++++++++++++---------------------------- include/drm/drm_mm.h | 2 +- 2 files changed, 18 insertions(+), 29 deletions(-)
diff --git a/drivers/gpu/drm/drm_mm.c b/drivers/gpu/drm/drm_mm.c index b751b8e..e6fce66 100644 --- a/drivers/gpu/drm/drm_mm.c +++ b/drivers/gpu/drm/drm_mm.c @@ -244,11 +244,13 @@ static void drm_mm_insert_helper_range(struct drm_mm_node *hole_node,
BUG_ON(!hole_node->hole_follows || node->allocated);
- if (mm->color_adjust) - mm->color_adjust(hole_node, color, &adj_start, &adj_end); - if (adj_start < start) adj_start = start; + if (adj_end > end) + adj_end = end; + + if (mm->color_adjust) + mm->color_adjust(hole_node, color, &adj_start, &adj_end);
if (alignment) { unsigned tmp = adj_start % alignment; @@ -519,7 +521,7 @@ void drm_mm_init_scan(struct drm_mm *mm, mm->scan_size = size; mm->scanned_blocks = 0; mm->scan_hit_start = 0; - mm->scan_hit_size = 0; + mm->scan_hit_end = 0; mm->scan_check_range = 0; mm->prev_scanned_node = NULL; } @@ -546,7 +548,7 @@ void drm_mm_init_scan_with_range(struct drm_mm *mm, mm->scan_size = size; mm->scanned_blocks = 0; mm->scan_hit_start = 0; - mm->scan_hit_size = 0; + mm->scan_hit_end = 0; mm->scan_start = start; mm->scan_end = end; mm->scan_check_range = 1; @@ -565,8 +567,7 @@ int drm_mm_scan_add_block(struct drm_mm_node *node) struct drm_mm *mm = node->mm; struct drm_mm_node *prev_node; unsigned long hole_start, hole_end; - unsigned long adj_start; - unsigned long adj_end; + unsigned long adj_start, adj_end;
mm->scanned_blocks++;
@@ -583,14 +584,8 @@ int drm_mm_scan_add_block(struct drm_mm_node *node) node->node_list.next = &mm->prev_scanned_node->node_list; mm->prev_scanned_node = node;
- hole_start = drm_mm_hole_node_start(prev_node); - hole_end = drm_mm_hole_node_end(prev_node); - - adj_start = hole_start; - adj_end = hole_end; - - if (mm->color_adjust) - mm->color_adjust(prev_node, mm->scan_color, &adj_start, &adj_end); + adj_start = hole_start = drm_mm_hole_node_start(prev_node); + adj_end = hole_end = drm_mm_hole_node_end(prev_node);
if (mm->scan_check_range) { if (adj_start < mm->scan_start) @@ -599,11 +594,14 @@ int drm_mm_scan_add_block(struct drm_mm_node *node) adj_end = mm->scan_end; }
+ if (mm->color_adjust) + mm->color_adjust(prev_node, mm->scan_color, + &adj_start, &adj_end); + if (check_free_hole(adj_start, adj_end, mm->scan_size, mm->scan_alignment)) { mm->scan_hit_start = hole_start; - mm->scan_hit_size = hole_end; - + mm->scan_hit_end = hole_end; return 1; }
@@ -639,19 +637,10 @@ int drm_mm_scan_remove_block(struct drm_mm_node *node) node_list);
prev_node->hole_follows = node->scanned_preceeds_hole; - INIT_LIST_HEAD(&node->node_list); list_add(&node->node_list, &prev_node->node_list);
- /* Only need to check for containement because start&size for the - * complete resulting free block (not just the desired part) is - * stored. */ - if (node->start >= mm->scan_hit_start && - node->start + node->size - <= mm->scan_hit_start + mm->scan_hit_size) { - return 1; - } - - return 0; + return (__drm_mm_hole_node_end(node) > mm->scan_hit_start && + node->start < mm->scan_hit_end); } EXPORT_SYMBOL(drm_mm_scan_remove_block);
diff --git a/include/drm/drm_mm.h b/include/drm/drm_mm.h index cd45365..58b8979 100644 --- a/include/drm/drm_mm.h +++ b/include/drm/drm_mm.h @@ -70,7 +70,7 @@ struct drm_mm { unsigned long scan_color; unsigned long scan_size; unsigned long scan_hit_start; - unsigned scan_hit_size; + unsigned long scan_hit_end; unsigned scanned_blocks; unsigned long scan_start; unsigned long scan_end;
On Wed, Dec 19, 2012 at 04:51:06PM +0000, Chris Wilson wrote:
Avoid clobbering adjacent blocks if they happen to expire earlier and amalgamate together to form the requested hole.
In passing this fixes a regression from commit ea7b1dd44867e9cd6bac67e7c9fc3f128b5b255c Author: Daniel Vetter daniel.vetter@ffwll.ch Date: Fri Feb 18 17:59:12 2011 +0100
drm: mm: track free areas implicitly
which swaps the end address for size (with a potential overflow) and effectively causes the eviction code to clobber almost all earlier buffers above the evictee.
v2: Check the original hole not the adjusted as the coloring may confuse us when later searching for the overlapping nodes. Also make sure that we do apply the range restriction and color adjustment in the same order for both scanning, searching and insertion.
v3: Send the version that was actually tested.
Signed-off-by: Chris Wilson chris@chris-wilson.co.uk Cc: Daniel Vetter daniel.vetter@ffwll.ch
Picked up for -fixes with bugzilla link and Norberts tested-by added, thanks for the patch. -Daniel
dri-devel@lists.freedesktop.org