Re: [Qemu-devel] [PATCH 02/10] qemu_ram_foreach_block: pass up error value, and down the ramblock name

["Michael R. Hines" <mrhines@linux.vnet.ibm.com>]

On 04/20/2015 10:57 AM, Dr. David Alan Gilbert (git) wrote:
> From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
>
> check the return value of the function it calls and error if it's non-0
> Fixup qemu_rdma_init_one_block that is the only current caller,
>    and rdma_add_block the only function it calls using it.
>
> Pass the name of the ramblock to the function; helps in debugging.
>
> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
> Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
> ---
>   exec.c                    | 10 ++++++++--
>   include/exec/cpu-common.h |  4 ++--
>   migration/rdma.c          |  4 ++--
>   3 files changed, 12 insertions(+), 6 deletions(-)
>
> diff --git a/exec.c b/exec.c
> index 874ecfc..7693794 100644
> --- a/exec.c
> +++ b/exec.c
> @@ -3067,14 +3067,20 @@ bool cpu_physical_memory_is_io(hwaddr phys_addr)
>                memory_region_is_romd(mr));
>   }
>
> -void qemu_ram_foreach_block(RAMBlockIterFunc func, void *opaque)
> +int qemu_ram_foreach_block(RAMBlockIterFunc func, void *opaque)
>   {
>       RAMBlock *block;
> +    int ret = 0;
>
>       rcu_read_lock();
>       QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
> -        func(block->host, block->offset, block->used_length, opaque);
> +        ret = func(block->idstr, block->host, block->offset,
> +                   block->used_length, opaque);
> +        if (ret) {
> +            break;
> +        }
>       }
>       rcu_read_unlock();
> +    return ret;
>   }
>   #endif
> diff --git a/include/exec/cpu-common.h b/include/exec/cpu-common.h
> index fcc3162..2abecac 100644
> --- a/include/exec/cpu-common.h
> +++ b/include/exec/cpu-common.h
> @@ -125,10 +125,10 @@ void cpu_flush_icache_range(hwaddr start, int len);
>   extern struct MemoryRegion io_mem_rom;
>   extern struct MemoryRegion io_mem_notdirty;
>
> -typedef void (RAMBlockIterFunc)(void *host_addr,
> +typedef int (RAMBlockIterFunc)(const char *block_name, void *host_addr,
>       ram_addr_t offset, ram_addr_t length, void *opaque);
>
> -void qemu_ram_foreach_block(RAMBlockIterFunc func, void *opaque);
> +int qemu_ram_foreach_block(RAMBlockIterFunc func, void *opaque);
>
>   #endif
>
> diff --git a/migration/rdma.c b/migration/rdma.c
> index 089adcf..38e5f44 100644
> --- a/migration/rdma.c
> +++ b/migration/rdma.c
> @@ -570,10 +570,10 @@ static int rdma_add_block(RDMAContext *rdma, void *host_addr,
>    * in advanced before the migration starts. This tells us where the RAM blocks
>    * are so that we can register them individually.
>    */
> -static void qemu_rdma_init_one_block(void *host_addr,
> +static int qemu_rdma_init_one_block(const char *block_name, void *host_addr,
>       ram_addr_t block_offset, ram_addr_t length, void *opaque)
>   {
> -    rdma_add_block(opaque, host_addr, block_offset, length);
> +    return rdma_add_block(opaque, host_addr, block_offset, length);
>   }
>
>   /*

Shame on me for not checking the return value =)

Reviewed-by: Michael R. Hines <mrhines@us.ibm.com>