Re: [PATCH v2 3/4] qemu-io: add -r option to register I/O buffer

[Eric Blake]

On Mon, Jan 30, 2023 at 04:54:14PM -0500, Stefan Hajnoczi wrote:
> The blk_register_buf() API is an optimization hint that allows some
> block drivers to avoid I/O buffer housekeeping or bounce buffers.
> 
> Add an -r option to register the I/O buffer so that qemu-io can be used
> to test the blk_register_buf() API. The next commit will add a test that
> uses the new option.
> 
> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
> ---
>  qemu-io-cmds.c | 167 +++++++++++++++++++++++++++++++++----------------
>  1 file changed, 114 insertions(+), 53 deletions(-)

Reviewed-by: Eric Blake <eblake@redhat.com>

> @@ -1277,7 +1322,7 @@ static int writev_f(BlockBackend *blk, int argc, char 
> **argv)
>      int pattern = 0xcd;
>      QEMUIOVector qiov;
>  
> -    while ((c = getopt(argc, argv, "CfqP:")) != -1) {
> +    while ((c = getopt(argc, argv, "CfqrP:")) != -1) {

This one is still odd - it is neither case-sensitive nor
case-insensitive in order, because of P: coming after qr.

> @@ -1476,7 +1529,7 @@ static int aio_read_f(BlockBackend *blk, int argc, char 
> **argv)
>      struct aio_ctx *ctx = g_new0(struct aio_ctx, 1);
>  
>      ctx->blk = blk;
> -    while ((c = getopt(argc, argv, "CP:iqv")) != -1) {
> +    while ((c = getopt(argc, argv, "CP:iqrv")) != -1) {

This one could at least argue that all capitals are before any
lower-case, although case-insensitive would put i before P:.

> @@ -1582,22 +1641,24 @@ static int aio_write_f(BlockBackend *blk, int argc, 
> char **argv)
>      int nr_iov, c;
>      int pattern = 0xcd;
>      struct aio_ctx *ctx = g_new0(struct aio_ctx, 1);
> -    BdrvRequestFlags flags = 0;
>  
>      ctx->blk = blk;
> -    while ((c = getopt(argc, argv, "CfiqP:uz")) != -1) {
> +    while ((c = getopt(argc, argv, "CfiqrP:uz")) != -1) {

Another odd spot where P: would fit better before qr.

Those are still minor, so I don't care if you further touch them
up. My R-b applies either way.

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
Virtualization:  qemu.org | libvirt.org