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| author | Stefan Hajnoczi <stefanha@redhat.com> | 2016-01-25 13:33:20 +0000 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2016-02-09 15:45:26 +0100 |
| commit | 5b82b703b69acc67b78b98a5efc897a3912719eb (patch) | |
| tree | f0532356113606ee7c64560e69149e865852a43c /qemu-char.c | |
| parent | 8bafcb21643a39a5b29109f8bd5ee5a6f0f6850b (diff) | |
memory: RCU ram_list.dirty_memory[] for safe RAM hotplug
Although accesses to ram_list.dirty_memory[] use atomics so multiple
threads can safely dirty the bitmap, the data structure is not fully
thread-safe yet.
This patch handles the RAM hotplug case where ram_list.dirty_memory[] is
grown. ram_list.dirty_memory[] is change from a regular bitmap to an
RCU array of pointers to fixed-size bitmap blocks. Threads can continue
accessing bitmap blocks while the array is being extended. See the
comments in the code for an in-depth explanation of struct
DirtyMemoryBlocks.
I have tested that live migration with virtio-blk dataplane works.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <1453728801-5398-2-git-send-email-stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'qemu-char.c')
0 files changed, 0 insertions, 0 deletions