diff options
| author | Sebastian Ott <sebott@linux.vnet.ibm.com> | 2016-08-02 14:04:13 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-08-02 19:35:07 -0400 |
| commit | f003a1f182bb821f13775338a4bf8711830f927a (patch) | |
| tree | 74d6093d44a21328cebb5420b970fb059d080547 | |
| parent | 4cad35a7ca690eabf0d241062ce9e59693ec03e7 (diff) | |
lib/iommu-helper: skip to next segment
When a large enough area in the iommu bitmap is found but would span a
boundary we continue the search starting from the next bit position.
For large allocations this can lead to several useless invocations of
bitmap_find_next_zero_area() and iommu_is_span_boundary().
Continue the search from the start of the next segment (which is the
next bit position such that we'll not cross the same segment boundary
again).
Link: http://lkml.kernel.org/r/alpine.LFD.2.20.1606081910070.3211@schleppi
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | lib/iommu-helper.c | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/lib/iommu-helper.c b/lib/iommu-helper.c index c27e269210c4..a816f3a80625 100644 --- a/lib/iommu-helper.c +++ b/lib/iommu-helper.c @@ -29,8 +29,7 @@ again: index = bitmap_find_next_zero_area(map, size, start, nr, align_mask); if (index < size) { if (iommu_is_span_boundary(index, nr, shift, boundary_size)) { - /* we could do more effectively */ - start = index + 1; + start = ALIGN(shift + index, boundary_size) - shift; goto again; } bitmap_set(map, index, nr); |