Re: [Qemu-devel] [PATCH 35/41] migration: use QEMUFile for writing outgoing migration data

[Orit Wasserman]

On 02/15/2013 07:47 PM, Paolo Bonzini wrote:
> Second, drop the file descriptor indirection, and write directly to the
> QEMUFile.
> 
> Signed-off-by: Paolo Bonzini <address@hidden>
> ---
>  include/migration/migration.h |    4 ---
>  migration-exec.c              |   12 -----------
>  migration-fd.c                |   12 -----------
>  migration-tcp.c               |   12 -----------
>  migration-unix.c              |   12 -----------
>  migration.c                   |   44 +++++-----------------------------------
>  6 files changed, 6 insertions(+), 90 deletions(-)
> 
> diff --git a/include/migration/migration.h b/include/migration/migration.h
> index cf3e81c..bde13c2 100644
> --- a/include/migration/migration.h
> +++ b/include/migration/migration.h
> @@ -40,10 +40,6 @@ struct MigrationState
>      QEMUFile *file;
>      QEMUFile *migration_file;
>  
> -    int fd;
> -    int (*get_error)(MigrationState *s);
> -    int (*write)(MigrationState *s, const void *buff, size_t size);
> -
>      int state;
>      MigrationParams params;
>      int64_t total_time;
> diff --git a/migration-exec.c b/migration-exec.c
> index 8c3f720..1c539de 100644
> --- a/migration-exec.c
> +++ b/migration-exec.c
> @@ -33,16 +33,6 @@
>      do { } while (0)
>  #endif
>  
> -static int file_errno(MigrationState *s)
> -{
> -    return errno;
> -}
> -
> -static int file_write(MigrationState *s, const void * buf, size_t size)
> -{
> -    return write(s->fd, buf, size);
> -}
> -
>  void exec_start_outgoing_migration(MigrationState *s, const char *command, 
> Error **errp)
>  {
>      s->migration_file = qemu_popen_cmd(command, "w");
> @@ -51,8 +41,6 @@ void exec_start_outgoing_migration(MigrationState *s, const 
> char *command, Error
>          return;
>      }
>  
> -    s->get_error = file_errno;
> -    s->write = file_write;
>      migrate_fd_connect(s);
>  }
>  
> diff --git a/migration-fd.c b/migration-fd.c
> index 4636457..07c758a 100644
> --- a/migration-fd.c
> +++ b/migration-fd.c
> @@ -30,16 +30,6 @@
>      do { } while (0)
>  #endif
>  
> -static int fd_errno(MigrationState *s)
> -{
> -    return errno;
> -}
> -
> -static int fd_write(MigrationState *s, const void * buf, size_t size)
> -{
> -    return write(s->fd, buf, size);
> -}
> -
>  void fd_start_outgoing_migration(MigrationState *s, const char *fdname, 
> Error **errp)
>  {
>      int fd = monitor_get_fd(cur_mon, fdname, errp);
> @@ -48,8 +38,6 @@ void fd_start_outgoing_migration(MigrationState *s, const 
> char *fdname, Error **
>      }
>      s->migration_file = qemu_fdopen(fd, "wb");
>  
> -    s->get_error = fd_errno;
> -    s->write = fd_write;
>      migrate_fd_connect(s);
>  }
>  
> diff --git a/migration-tcp.c b/migration-tcp.c
> index 1e8e004..5ea4f3d 100644
> --- a/migration-tcp.c
> +++ b/migration-tcp.c
> @@ -29,16 +29,6 @@
>      do { } while (0)
>  #endif
>  
> -static int socket_errno(MigrationState *s)
> -{
> -    return socket_error();
> -}
> -
> -static int socket_write(MigrationState *s, const void * buf, size_t size)
> -{
> -    return send(s->fd, buf, size, 0);
> -}
> -
>  static void tcp_wait_for_connect(int fd, void *opaque)
>  {
>      MigrationState *s = opaque;
> @@ -56,8 +46,6 @@ static void tcp_wait_for_connect(int fd, void *opaque)
>  
>  void tcp_start_outgoing_migration(MigrationState *s, const char *host_port, 
> Error **errp)
>  {
> -    s->get_error = socket_errno;
> -    s->write = socket_write;
>      inet_nonblocking_connect(host_port, tcp_wait_for_connect, s, errp);
>  }
>  
> diff --git a/migration-unix.c b/migration-unix.c
> index 11917f4..64bfa31 100644
> --- a/migration-unix.c
> +++ b/migration-unix.c
> @@ -29,16 +29,6 @@
>      do { } while (0)
>  #endif
>  
> -static int unix_errno(MigrationState *s)
> -{
> -    return errno;
> -}
> -
> -static int unix_write(MigrationState *s, const void * buf, size_t size)
> -{
> -    return write(s->fd, buf, size);
> -}
> -
>  static void unix_wait_for_connect(int fd, void *opaque)
>  {
>      MigrationState *s = opaque;
> @@ -56,8 +46,6 @@ static void unix_wait_for_connect(int fd, void *opaque)
>  
>  void unix_start_outgoing_migration(MigrationState *s, const char *path, 
> Error **errp)
>  {
> -    s->get_error = unix_errno;
> -    s->write = unix_write;
>      unix_nonblocking_connect(path, unix_wait_for_connect, s, errp);
>  }
>  
> diff --git a/migration.c b/migration.c
> index 9cffdd4..68d47cd 100644
> --- a/migration.c
> +++ b/migration.c
> @@ -291,25 +291,6 @@ void migrate_fd_error(MigrationState *s)
>      notifier_list_notify(&migration_state_notifiers, s);
>  }
>  
> -static ssize_t migrate_fd_put_buffer(MigrationState *s, const void *data,
> -                                     size_t size)
> -{
> -    ssize_t ret;
> -
> -    if (s->state != MIG_STATE_ACTIVE) {
> -        return -EIO;
> -    }
> -
> -    do {
> -        ret = s->write(s, data, size);
> -    } while (ret == -1 && ((s->get_error(s)) == EINTR));
> -
> -    if (ret == -1)
> -        ret = -(s->get_error(s));
> -
> -    return ret;
> -}
> -
>  static void migrate_fd_cancel(MigrationState *s)
>  {
>      DPRINTF("cancelling migration\n");
> @@ -323,7 +304,6 @@ int migrate_fd_close(MigrationState *s)
>      if (s->migration_file != NULL) {
>          rc = qemu_fclose(s->migration_file);
>          s->migration_file = NULL;
> -        s->fd = -1;
>      }
>      return rc;
>  }
> @@ -508,8 +488,6 @@ static int migration_put_buffer(void *opaque, const 
> uint8_t *buf,
>                                 int64_t pos, int size)
>  {
>      MigrationState *s = opaque;
> -    ssize_t ret;
> -    size_t sent;
>  
>      DPRINTF("putting %d bytes at %" PRId64 "\n", size, pos);
>  
> @@ -517,22 +495,13 @@ static int migration_put_buffer(void *opaque, const 
> uint8_t *buf,
>          return size;
>      }
>  
> -    sent = 0;
> -    while (size) {
> -        ret = migrate_fd_put_buffer(s, buf, size);
> -        if (ret <= 0) {
> -            DPRINTF("error flushing data, %zd\n", ret);
> -            return ret;
> -        } else {
> -            DPRINTF("flushed %zd byte(s)\n", ret);
> -            sent += ret;
> -            buf += ret;
> -            size -= ret;
> -            s->bytes_xfer += ret;
> -        }
> +    qemu_put_buffer(s->migration_file, buf, size);
> +    if (qemu_file_get_error(s->migration_file)) {
> +        return qemu_file_get_error(s->migration_file);
>      }
>  
> -    return sent;
> +    s->bytes_xfer += size;
> +    return size;
>  }
>  
>  static int migration_close(void *opaque)
> @@ -553,7 +522,7 @@ static int migration_get_fd(void *opaque)
>  {
>      MigrationState *s = opaque;
>  
> -    return s->fd;
> +    return qemu_get_fd(s->migration_file);
>  }
>  
>  /*
> @@ -695,7 +664,6 @@ void migrate_fd_connect(MigrationState *s)
>      s->xfer_limit = s->bandwidth_limit / XFER_LIMIT_RATIO;
>  
>      s->cleanup_bh = qemu_bh_new(migrate_fd_cleanup, s);
> -    s->fd = qemu_get_fd(s->migration_file);
>      s->file = qemu_fopen_ops(s, &migration_file_ops);
>  
>      qemu_thread_create(&s->thread, migration_thread, s,
> 
Reviewed-by: Orit Wasserman <address@hidden>