Messages in this thread Patch in this message |  | | | Subject | [PATCH 2/8] kmemleak: Allow rescheduling during an object scanning | | From | Catalin Marinas <> | | Date | Fri, 24 Jul 2009 17:12:13 +0100 |
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If the object size is bigger than a predefined value (4K in this case), release the object lock during scanning and call cond_resched(). Re-acquire the lock after rescheduling and test whether the object is still valid.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> --- mm/kmemleak.c | 19 +++++++++++++++---- 1 files changed, 15 insertions(+), 4 deletions(-) diff --git a/mm/kmemleak.c b/mm/kmemleak.c index 7e8e4b0..c665626 100644 --- a/mm/kmemleak.c +++ b/mm/kmemleak.c @@ -107,6 +107,7 @@ #define SECS_FIRST_SCAN 60 /* delay before the first scan */ #define SECS_SCAN_WAIT 600 /* subsequent auto scanning delay */ #define GRAY_LIST_PASSES 25 /* maximum number of gray list scans */ +#define MAX_SCAN_SIZE 4096 /* maximum size of a scanned block */ #define BYTES_PER_POINTER sizeof(void *) @@ -950,10 +951,20 @@ static void scan_object(struct kmemleak_object *object) if (!(object->flags & OBJECT_ALLOCATED)) /* already freed object */ goto out; - if (hlist_empty(&object->area_list)) - scan_block((void *)object->pointer, - (void *)(object->pointer + object->size), object, 0); - else + if (hlist_empty(&object->area_list)) { + void *start = (void *)object->pointer; + void *end = (void *)(object->pointer + object->size); + + while (start < end && (object->flags & OBJECT_ALLOCATED)) { + scan_block(start, min(start + MAX_SCAN_SIZE, end), + object, 0); + start += MAX_SCAN_SIZE; + + spin_unlock_irqrestore(&object->lock, flags); + cond_resched(); + spin_lock_irqsave(&object->lock, flags); + } + } else hlist_for_each_entry(area, elem, &object->area_list, node) scan_block((void *)(object->pointer + area->offset), (void *)(object->pointer + area->offset
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