From: Bruce Richardson <bruce.richardson@intel.com>
To: "Roger B. Melton" <rmelton@cisco.com>
Cc: dev@dpdk.org
Subject: Re: [dpdk-dev] [PATCH 4/4] ethdev: check support for rx_queue_count and descriptor_done fns
Date: Mon, 15 Jun 2015 11:14:18 +0100 [thread overview]
Message-ID: <20150615101418.GA3872@bricha3-MOBL3> (raw)
In-Reply-To: <557B17C8.3090300@cisco.com>
On Fri, Jun 12, 2015 at 01:32:56PM -0400, Roger B. Melton wrote:
> Hi Bruce, Comment in-line. Regards, Roger
>
> On 6/12/15 7:28 AM, Bruce Richardson wrote:
> >The functions rte_eth_rx_queue_count and rte_eth_descriptor_done are
> >supported by very few PMDs. Therefore, it is best to check for support
> >for the functions in the ethdev library, so as to avoid crashes
> >at run-time if the application goes to use those APIs. The performance
> >impact of this change should be very small as this is a predictable
> >branch in the function.
> >
> >Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
> >---
> > lib/librte_ether/rte_ethdev.h | 8 ++++++--
> > 1 file changed, 6 insertions(+), 2 deletions(-)
> >
> >diff --git a/lib/librte_ether/rte_ethdev.h b/lib/librte_ether/rte_ethdev.h
> >index 827ca3e..9ad1b6a 100644
> >--- a/lib/librte_ether/rte_ethdev.h
> >+++ b/lib/librte_ether/rte_ethdev.h
> >@@ -2496,6 +2496,8 @@ rte_eth_rx_burst(uint8_t port_id, uint16_t queue_id,
> > * The queue id on the specific port.
> > * @return
> > * The number of used descriptors in the specific queue.
> >+ * NOTE: if function is not supported by device this call
> >+ * returns (uint32_t)-ENOTSUP
> > */
> > static inline uint32_t
>
> Why not change the return type to int32_t?
> In this way, the caller isn't required to make the assumption that a large
> queue count indicates an error. < 0 means error, other wise it's a valid
> queue count.
>
> This approach would be consistent with other APIs.
>
Yes, good point, I should see about that. One thing I'm unsure of, though, is
does this count as ABI breakage? I don't see how it should break any older
apps, since the return type is the same size, but I'm not sure as we are
changing the return type of the function.
Neil, can you perhaps comment here? Is changing uint32_t to int32_t ok, from
an ABI point of view?
Regards,
/Bruce
next prev parent reply other threads:[~2015-06-15 10:14 UTC|newest]
Thread overview: 55+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-06-12 11:28 [dpdk-dev] [PATCH 0/4] ethdev: Add checks for function support in driver Bruce Richardson
2015-06-12 11:28 ` [dpdk-dev] [PATCH 1/4] ethdev: rename macros to have RTE_ETH prefix Bruce Richardson
2015-06-12 11:28 ` [dpdk-dev] [PATCH 2/4] ethdev: move RTE_ETH_FPTR_OR_ERR macros to header Bruce Richardson
2015-06-12 11:28 ` [dpdk-dev] [PATCH 3/4] ethdev: remove duplicated debug functions Bruce Richardson
2015-06-12 11:28 ` [dpdk-dev] [PATCH 4/4] ethdev: check support for rx_queue_count and descriptor_done fns Bruce Richardson
2015-06-12 17:32 ` Roger B. Melton
2015-06-15 10:14 ` Bruce Richardson [this message]
2015-07-06 15:11 ` Thomas Monjalon
2015-07-26 20:44 ` Thomas Monjalon
2015-09-09 15:09 ` [dpdk-dev] [PATCH v2 0/4] ethdev: minor cleanup Bruce Richardson
2015-09-09 15:09 ` [dpdk-dev] [PATCH v2 1/4] ethdev: rename macros to have RTE_ETH prefix Bruce Richardson
2015-09-09 15:09 ` [dpdk-dev] [PATCH v2 2/4] ethdev: move error checking macros to header Bruce Richardson
2015-09-09 15:09 ` [dpdk-dev] [PATCH v2 3/4] ethdev: remove duplicated debug functions Bruce Richardson
2015-09-09 15:09 ` [dpdk-dev] [PATCH v2 4/4] ethdev: check driver support for functions Bruce Richardson
2015-09-28 10:23 ` [dpdk-dev] [PATCH v2 0/4] ethdev: minor cleanup Bruce Richardson
2015-11-03 1:11 ` Thomas Monjalon
2015-11-03 10:06 ` Bruce Richardson
2015-11-03 12:00 ` [dpdk-dev] [PATCH v3 " Bruce Richardson
2015-11-03 12:00 ` [dpdk-dev] [PATCH v3 1/4] ethdev: rename macros to have RTE_ETH prefix Bruce Richardson
2015-11-03 12:00 ` [dpdk-dev] [PATCH v3 2/4] ethdev: move error checking macros to header Bruce Richardson
2015-11-04 1:19 ` Thomas Monjalon
2015-11-04 10:24 ` Adrien Mazarguil
2015-11-04 14:10 ` Bruce Richardson
2015-11-04 15:25 ` Adrien Mazarguil
2015-11-04 18:39 ` Stephen Hemminger
2015-11-05 15:09 ` Adrien Mazarguil
2015-11-05 15:17 ` Bruce Richardson
2015-11-06 11:49 ` Bruce Richardson
2015-11-06 17:10 ` Bruce Richardson
2015-11-06 17:22 ` Bruce Richardson
2015-11-09 13:39 ` Adrien Mazarguil
2015-11-09 13:50 ` Adrien Mazarguil
2015-11-09 14:02 ` Richardson, Bruce
2015-11-10 10:31 ` Declan Doherty
2015-11-10 16:08 ` Adrien Mazarguil
2015-11-10 16:21 ` Richardson, Bruce
2015-11-10 17:12 ` Adrien Mazarguil
2015-11-11 10:51 ` Bruce Richardson
2015-11-03 12:00 ` [dpdk-dev] [PATCH v3 3/4] ethdev: remove duplicated debug functions Bruce Richardson
2015-11-03 12:00 ` [dpdk-dev] [PATCH v3 4/4] ethdev: check driver support for functions Bruce Richardson
2015-11-03 22:00 ` Stephen Hemminger
2015-11-04 14:15 ` Bruce Richardson
2015-11-17 12:21 ` [dpdk-dev] [PATCH v4 0/2] ethdev: debug code cleanup Bruce Richardson
2015-11-17 12:21 ` [dpdk-dev] [PATCH v4 1/2] ethdev: remove duplicated debug functions Bruce Richardson
2015-11-17 12:21 ` [dpdk-dev] [PATCH v4 2/2] ethdev: add sanity checks to functions Bruce Richardson
2015-11-17 15:53 ` Stephen Hemminger
2015-11-24 14:56 ` Bruce Richardson
2015-11-24 15:29 ` Thomas Monjalon
2015-11-24 15:45 ` Bruce Richardson
2015-11-24 15:48 ` Thomas Monjalon
2015-11-24 17:37 ` [dpdk-dev] [PATCH v5 0/2] ethdev: debug code cleanup Bruce Richardson
2015-11-24 17:37 ` [dpdk-dev] [PATCH v5 1/2] ethdev: remove duplicated debug functions Bruce Richardson
2015-11-25 18:14 ` Thomas Monjalon
2015-11-24 17:37 ` [dpdk-dev] [PATCH v5 2/2] ethdev: add sanity checks to functions Bruce Richardson
2015-11-25 18:21 ` [dpdk-dev] [PATCH v5 0/2] ethdev: debug code cleanup Thomas Monjalon
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20150615101418.GA3872@bricha3-MOBL3 \
--to=bruce.richardson@intel.com \
--cc=dev@dpdk.org \
--cc=rmelton@cisco.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).