Commit 92ca922f0a19145f2dcc99d84fe656fa55b52c2e
Committed by
Linus Torvalds
Linus Torvalds
1 parent
c2cddf9919
Exists in
master
and in
20 other branches
vmalloc: walk vmap_areas by sorted list instead of rb_next()
There's a walk by repeating rb_next to find a suitable hole. Could be simply replaced by walk on the sorted vmap_area_list. More simpler and efficient. Mutation of the list and tree only happens in pair within __insert_vmap_area and __free_vmap_area, under protection of vmap_area_lock. The patch code is also under vmap_area_lock, so the list walk is safe, and consistent with the tree walk. Tested on SMP by repeating batch of vmalloc anf vfree for random sizes and rounds for hours. Signed-off-by: Hong Zhiguo <honkiko@gmail.com> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Showing 1 changed file with 4 additions and 4 deletions Side-by-side Diff
mm/vmalloc.c
| ... | ... | @@ -413,11 +413,11 @@ |
| 413 | 413 | if (addr + size - 1 < addr) |
| 414 | 414 | goto overflow; |
| 415 | 415 | |
| 416 | - n = rb_next(&first->rb_node); | |
| 417 | - if (n) | |
| 418 | - first = rb_entry(n, struct vmap_area, rb_node); | |
| 419 | - else | |
| 416 | + if (list_is_last(&first->list, &vmap_area_list)) | |
| 420 | 417 | goto found; |
| 418 | + | |
| 419 | + first = list_entry(first->list.next, | |
| 420 | + struct vmap_area, list); | |
| 421 | 421 | } |
| 422 | 422 | |
| 423 | 423 | found: |