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| author | Peter Xu <peterx@redhat.com> | 2022-10-04 14:24:29 -0400 |
|---|---|---|
| committer | Juan Quintela <quintela@redhat.com> | 2022-11-21 11:58:10 +0100 |
| commit | cedb70eafb4fd51d9c714981509d97b9f4055be5 (patch) | |
| tree | a230b94aab982dab7966e935680acd1ac408e229 /include/exec/ram_addr.h | |
| parent | afed4273b5c9438dfbaa0b4762d0433f295ccdc1 (diff) | |
| download | qemu-cedb70eafb4fd51d9c714981509d97b9f4055be5.zip qemu-cedb70eafb4fd51d9c714981509d97b9f4055be5.tar.gz qemu-cedb70eafb4fd51d9c714981509d97b9f4055be5.tar.bz2 | |
migration: Use non-atomic ops for clear log bitmap
Since we already have bitmap_mutex to protect either the dirty bitmap or
the clear log bitmap, we don't need atomic operations to set/clear/test on
the clear log bitmap. Switching all ops from atomic to non-atomic
versions, meanwhile touch up the comments to show which lock is in charge.
Introduced non-atomic version of bitmap_test_and_clear_atomic(), mostly the
same as the atomic version but simplified a few places, e.g. dropped the
"old_bits" variable, and also the explicit memory barriers.
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Diffstat (limited to 'include/exec/ram_addr.h')
| -rw-r--r-- | include/exec/ram_addr.h | 11 |
1 files changed, 6 insertions, 5 deletions
diff --git a/include/exec/ram_addr.h b/include/exec/ram_addr.h index 1500680..f4fb6a2 100644 --- a/include/exec/ram_addr.h +++ b/include/exec/ram_addr.h @@ -42,7 +42,8 @@ static inline long clear_bmap_size(uint64_t pages, uint8_t shift) } /** - * clear_bmap_set: set clear bitmap for the page range + * clear_bmap_set: set clear bitmap for the page range. Must be with + * bitmap_mutex held. * * @rb: the ramblock to operate on * @start: the start page number @@ -55,12 +56,12 @@ static inline void clear_bmap_set(RAMBlock *rb, uint64_t start, { uint8_t shift = rb->clear_bmap_shift; - bitmap_set_atomic(rb->clear_bmap, start >> shift, - clear_bmap_size(npages, shift)); + bitmap_set(rb->clear_bmap, start >> shift, clear_bmap_size(npages, shift)); } /** - * clear_bmap_test_and_clear: test clear bitmap for the page, clear if set + * clear_bmap_test_and_clear: test clear bitmap for the page, clear if set. + * Must be with bitmap_mutex held. * * @rb: the ramblock to operate on * @page: the page number to check @@ -71,7 +72,7 @@ static inline bool clear_bmap_test_and_clear(RAMBlock *rb, uint64_t page) { uint8_t shift = rb->clear_bmap_shift; - return bitmap_test_and_clear_atomic(rb->clear_bmap, page >> shift, 1); + return bitmap_test_and_clear(rb->clear_bmap, page >> shift, 1); } static inline bool offset_in_ramblock(RAMBlock *b, ram_addr_t offset) |