Netdev Archive on lore.kernel.org
 help / color / Atom feed
From: "Keller, Jacob E" <jacob.e.keller@intel.com>
To: Jiri Pirko <jiri@resnulli.us>
Cc: "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
	Jakub Kicinski <kuba@kernel.org>
Subject: RE: [net-next v2 07/11] devlink: report error once U32_MAX snapshot ids have been used
Date: Thu, 26 Mar 2020 16:09:44 +0000
Message-ID: <02874ECE860811409154E81DA85FBB58B6CA3E5E@fmsmsx101.amr.corp.intel.com> (raw)
In-Reply-To: <20200326073047.GJ11304@nanopsycho.orion>



> -----Original Message-----
> From: netdev-owner@vger.kernel.org <netdev-owner@vger.kernel.org> On
> Behalf Of Jiri Pirko
> Sent: Thursday, March 26, 2020 12:31 AM
> To: Keller, Jacob E <jacob.e.keller@intel.com>
> Cc: netdev@vger.kernel.org; Jakub Kicinski <kuba@kernel.org>
> Subject: Re: [net-next v2 07/11] devlink: report error once U32_MAX snapshot
> ids have been used
> 
> Thu, Mar 26, 2020 at 04:51:53AM CET, jacob.e.keller@intel.com wrote:
> >The devlink_snapshot_id_get() function returns a snapshot id. The
> >snapshot id is a u32, so there is no way to indicate an error code.
> >
> >Indeed, the two current callers of devlink_snapshot_id_get() assume that
> >a negative value is an error.
> 
> I don't see they do.
> 

You're right, they don't. I was confused when I wrote this because the previous version of this patch did change them to check for error, and then I realized we didn't need that patch and removed it, but forgot to update this.

Can fix this if we need a respin for another reason.

> 
> >
> >A future change is going to possibly add additional cases where this
> >function could fail. Refactor the function to return the snapshot id in
> >an argument, so that it can return zero or an error value.
> >
> >This ensures that snapshot ids cannot be confused with error values, and
> >aids in the future refactor of snapshot id allocation management.
> >
> >Because there is no current way to release previously used snapshot ids,
> >add a simple check ensuring that an error is reported in case the
> >snapshot_id would over flow.
> >
> >Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
> 
> The code looks good.
> 
> Reviewed-by: Jiri Pirko <jiri@mellanox.com>

  reply index

Thread overview: 33+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-03-26  3:51 [net-next v2 00/11] implement DEVLINK_CMD_REGION_NEW Jacob Keller
2020-03-26  3:51 ` [net-next v2 01/11] devlink: prepare to support region operations Jacob Keller
2020-03-26  3:51 ` [net-next v2 02/11] devlink: convert snapshot destructor callback to region op Jacob Keller
2020-03-26  3:51 ` [net-next v2 03/11] devlink: trivial: fix tab in function documentation Jacob Keller
2020-03-26  3:51 ` [net-next v2 04/11] devlink: add function to take snapshot while locked Jacob Keller
2020-03-26  3:51 ` [net-next v2 05/11] devlink: use -ENOSPC to indicate no more room for snapshots Jacob Keller
2020-03-26  7:24   ` Jiri Pirko
2020-03-26  3:51 ` [net-next v2 06/11] devlink: extract snapshot id allocation to helper function Jacob Keller
2020-03-26  7:25   ` Jiri Pirko
2020-03-26  3:51 ` [net-next v2 07/11] devlink: report error once U32_MAX snapshot ids have been used Jacob Keller
2020-03-26  7:30   ` Jiri Pirko
2020-03-26 16:09     ` Keller, Jacob E [this message]
2020-03-26  3:51 ` [net-next v2 08/11] devlink: track snapshot id usage count using an xarray Jacob Keller
2020-03-26  8:35   ` Jiri Pirko
2020-03-26  3:51 ` [net-next v2 09/11] devlink: implement DEVLINK_CMD_REGION_NEW Jacob Keller
2020-03-26  8:51   ` Jiri Pirko
2020-03-26  8:52   ` Jiri Pirko
2020-03-26 16:19     ` Jacob Keller
2020-03-26 21:10       ` Jiri Pirko
2020-03-26  3:51 ` [net-next v2 10/11] netdevsim: support taking immediate snapshot via devlink Jacob Keller
2020-03-26  9:00   ` Jiri Pirko
2020-03-26  3:51 ` [net-next v2 11/11] ice: add a devlink region for dumping NVM contents Jacob Keller
2020-03-26  9:02   ` Jiri Pirko
2020-03-26 16:23     ` Jacob Keller
2020-03-26 21:11       ` Jiri Pirko
2020-03-26  7:23 ` [net-next v2 00/11] implement DEVLINK_CMD_REGION_NEW Jiri Pirko
2020-03-26  7:51 ` Jiri Pirko
2020-03-26 16:15   ` Jacob Keller
2020-03-26 21:12     ` Jiri Pirko
2020-03-26  8:36 ` Jiri Pirko
2020-03-26  8:54 ` Jiri Pirko
2020-03-26 18:27 ` David Miller
2020-03-26 18:29   ` Jacob Keller

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=02874ECE860811409154E81DA85FBB58B6CA3E5E@fmsmsx101.amr.corp.intel.com \
    --to=jacob.e.keller@intel.com \
    --cc=jiri@resnulli.us \
    --cc=kuba@kernel.org \
    --cc=netdev@vger.kernel.org \
    /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

Netdev Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/netdev/0 netdev/git/0.git
	git clone --mirror https://lore.kernel.org/netdev/1 netdev/git/1.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 netdev netdev/ https://lore.kernel.org/netdev \
		netdev@vger.kernel.org
	public-inbox-index netdev

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.netdev


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git