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[Qemu-block] [PATCH 05/12] hbitmap: enable merging across granularities
From: |
John Snow |
Subject: |
[Qemu-block] [PATCH 05/12] hbitmap: enable merging across granularities |
Date: |
Wed, 19 Jun 2019 21:03:49 -0400 |
Signed-off-by: John Snow <address@hidden>
---
util/hbitmap.c | 22 +++++++++++++++++++++-
1 file changed, 21 insertions(+), 1 deletion(-)
diff --git a/util/hbitmap.c b/util/hbitmap.c
index 45d1725daf..0d6724b7bc 100644
--- a/util/hbitmap.c
+++ b/util/hbitmap.c
@@ -777,7 +777,17 @@ void hbitmap_truncate(HBitmap *hb, uint64_t size)
bool hbitmap_can_merge(const HBitmap *a, const HBitmap *b)
{
- return (a->size == b->size) && (a->granularity == b->granularity);
+ return (a->size == b->size);
+}
+
+static void hbitmap_sparse_merge(HBitmap *dst, const HBitmap *src)
+{
+ uint64_t offset = 0;
+ uint64_t count = src->orig_size;
+
+ while (hbitmap_next_dirty_area(src, &offset, &count)) {
+ hbitmap_set(dst, offset, count);
+ }
}
/**
@@ -804,6 +814,16 @@ bool hbitmap_merge(const HBitmap *a, const HBitmap *b,
HBitmap *result)
return true;
}
+ if (a->size != b->size) {
+ if (a != result) {
+ hbitmap_sparse_merge(result, a);
+ }
+ if (b != result) {
+ hbitmap_sparse_merge(result, b);
+ }
+ return true;
+ }
+
/* This merge is O(size), as BITS_PER_LONG and HBITMAP_LEVELS are constant.
* It may be possible to improve running times for sparsely populated maps
* by using hbitmap_iter_next, but this is suboptimal for dense maps.
--
2.21.0
[Qemu-block] [PATCH 08/12] iotests: add testing shim for script-style python tests, John Snow, 2019/06/19
[Qemu-block] [PATCH 05/12] hbitmap: enable merging across granularities,
John Snow <=
[Qemu-block] [PATCH 11/12] iotests: add test 257 for bitmap-mode backups, John Snow, 2019/06/19