migration: No need to take rcu during sync_dirty_bitmap

cpu_physical_memory_sync_dirty_bitmap() has one RAMBlock* as
parameter, which means that it must be with RCU read lock held
already.  Taking it again inside seems redundant.  Removing it.
Instead comment on the functions about the RCU read lock.

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20190603065056.25211-2-peterx@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
This commit is contained in:
Peter Xu 2019-06-03 14:50:46 +08:00 committed by Juan Quintela
parent 422314e751
commit 267691b65c
2 changed files with 2 additions and 4 deletions

View File

@ -409,6 +409,7 @@ static inline void cpu_physical_memory_clear_dirty_range(ram_addr_t start,
}
/* Called with RCU critical section */
static inline
uint64_t cpu_physical_memory_sync_dirty_bitmap(RAMBlock *rb,
ram_addr_t start,
@ -432,8 +433,6 @@ uint64_t cpu_physical_memory_sync_dirty_bitmap(RAMBlock *rb,
DIRTY_MEMORY_BLOCK_SIZE);
unsigned long page = BIT_WORD(start >> TARGET_PAGE_BITS);
rcu_read_lock();
src = atomic_rcu_read(
&ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION])->blocks;
@ -453,8 +452,6 @@ uint64_t cpu_physical_memory_sync_dirty_bitmap(RAMBlock *rb,
idx++;
}
}
rcu_read_unlock();
} else {
ram_addr_t offset = rb->offset;

View File

@ -1674,6 +1674,7 @@ static inline bool migration_bitmap_clear_dirty(RAMState *rs,
return ret;
}
/* Called with RCU critical section */
static void migration_bitmap_sync_range(RAMState *rs, RAMBlock *rb,
ram_addr_t length)
{