Re: [Qemu-devel] [PATCH v2 2/3] nbd/client: Trace all server option error messages

[Vladimir Sementsov-Ogievskiy]

19.12.2018 1:57, Eric Blake wrote:
> Not all servers send free-form text alongside option error replies, but
> for servers that do (such as qemu), we pass the server's message as a
> hint alongside our own error reporting.  However, it would also be
> useful to trace such server messages, since we can't guarantee how the
> hint may be consumed.
> 
> Signed-off-by: Eric Blake <address@hidden>

Reviewed-by: Vladimir Sementsov-Ogievskiy <address@hidden>

> ---
>   nbd/client.c     | 2 ++
>   nbd/trace-events | 1 +
>   2 files changed, 3 insertions(+)
> 
> diff --git a/nbd/client.c b/nbd/client.c
> index b4d457a19ad..0ad7147ed95 100644
> --- a/nbd/client.c
> +++ b/nbd/client.c
> @@ -171,6 +171,8 @@ static int nbd_handle_reply_err(QIOChannel *ioc, 
> NBDOptionReply *reply,
>               goto cleanup;
>           }
>           msg[reply->length] = '\0';
> +        trace_nbd_server_error_msg(reply->type,
> +                                   nbd_reply_type_lookup(reply->type), msg);
>       }
> 
>       switch (reply->type) {
> diff --git a/nbd/trace-events b/nbd/trace-events
> index 5e1d4afe8e6..5492042acbf 100644
> --- a/nbd/trace-events
> +++ b/nbd/trace-events
> @@ -1,6 +1,7 @@
>   # nbd/client.c
>   nbd_send_option_request(uint32_t opt, const char *name, uint32_t len) 
> "Sending option request %" PRIu32" (%s), len %" PRIu32
>   nbd_receive_option_reply(uint32_t option, const char *optname, uint32_t 
> type, const char *typename, uint32_t length) "Received option reply %" 
> PRIu32" (%s), type %" PRIu32" (%s), len %" PRIu32
> +nbd_server_error_msg(uint32_t err, const char *type, const char *msg) 
> "server reported error 0x%" PRIx32 " (%s) with additional message: %s"
>   nbd_reply_err_unsup(uint32_t option, const char *name) "server doesn't 
> understand request %" PRIu32 " (%s), attempting fallback"
>   nbd_opt_go_start(const char *name) "Attempting NBD_OPT_GO for export '%s'"
>   nbd_opt_go_success(void) "Export is good to go"
> 


-- 
Best regards,
Vladimir