* Juan Quintela (quint...@redhat.com) wrote:
> Signed-off-by: Juan Quintela <quint...@redhat.com>
I'm still pretty convinced that there's an existing problem with
this mutex can get init'd twice with no destroy on a second migration,
however you're not changing that (and it's not actually failed as
far as I can tell):
Reviewed-by: Dr. David Alan Gilbert <dgilb...@redhat.com>
> ---
> migration/ram.c | 15 ++++++++-------
> 1 file changed, 8 insertions(+), 7 deletions(-)
>
> diff --git a/migration/ram.c b/migration/ram.c
> index a890179..ae2b89f 100644
> --- a/migration/ram.c
> +++ b/migration/ram.c
> @@ -184,6 +184,8 @@ struct RAMState {
> uint64_t xbzrle_overflows;
> /* number of dirty bits in the bitmap */
> uint64_t migration_dirty_pages;
> + /* protects modification of the bitmap */
> + QemuMutex bitmap_mutex;
> };
> typedef struct RAMState RAMState;
>
> @@ -229,8 +231,6 @@ static ram_addr_t ram_save_remaining(void)
> return ram_state.migration_dirty_pages;
> }
>
> -static QemuMutex migration_bitmap_mutex;
> -
> /* used by the search for pages to send */
> struct PageSearchStatus {
> /* Current block being searched */
> @@ -652,13 +652,13 @@ static void migration_bitmap_sync(RAMState *rs)
> trace_migration_bitmap_sync_start();
> memory_global_dirty_log_sync();
>
> - qemu_mutex_lock(&migration_bitmap_mutex);
> + qemu_mutex_lock(&rs->bitmap_mutex);
> rcu_read_lock();
> QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
> migration_bitmap_sync_range(rs, block->offset, block->used_length);
> }
> rcu_read_unlock();
> - qemu_mutex_unlock(&migration_bitmap_mutex);
> + qemu_mutex_unlock(&rs->bitmap_mutex);
>
> trace_migration_bitmap_sync_end(rs->num_dirty_pages_period);
>
> @@ -1524,6 +1524,7 @@ static void ram_state_reset(RAMState *rs)
> void migration_bitmap_extend(ram_addr_t old, ram_addr_t new)
> {
> RAMState *rs = &ram_state;
> +
> /* called in qemu main thread, so there is
> * no writing race against this migration_bitmap
> */
> @@ -1537,7 +1538,7 @@ void migration_bitmap_extend(ram_addr_t old, ram_addr_t
> new)
> * it is safe to migration if migration_bitmap is cleared bit
> * at the same time.
> */
> - qemu_mutex_lock(&migration_bitmap_mutex);
> + qemu_mutex_lock(&rs->bitmap_mutex);
> bitmap_copy(bitmap->bmap, old_bitmap->bmap, old);
> bitmap_set(bitmap->bmap, old, new - old);
>
> @@ -1548,7 +1549,7 @@ void migration_bitmap_extend(ram_addr_t old, ram_addr_t
> new)
> bitmap->unsentmap = NULL;
>
> atomic_rcu_set(&migration_bitmap_rcu, bitmap);
> - qemu_mutex_unlock(&migration_bitmap_mutex);
> + qemu_mutex_unlock(&rs->bitmap_mutex);
> rs->migration_dirty_pages += new - old;
> call_rcu(old_bitmap, migration_bitmap_free, rcu);
> }
> @@ -1980,7 +1981,7 @@ static int ram_state_init(RAMState *rs)
> int64_t ram_bitmap_pages; /* Size of bitmap in pages, including gaps */
>
> memset(rs, 0, sizeof(*rs));
> - qemu_mutex_init(&migration_bitmap_mutex);
> + qemu_mutex_init(&rs->bitmap_mutex);
>
> if (migrate_use_xbzrle()) {
> XBZRLE_cache_lock();
> --
> 2.9.3
>
--
Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK
