From: Sowmini Varadhan <sowmini.varadhan@oracle.com>
To: Dave Kleikamp <dave.kleikamp@oracle.com>
Cc: Julian Calaby <julian.calaby@gmail.com>,
"David S. Miller" <davem@davemloft.net>,
netdev <netdev@vger.kernel.org>,
sparclinux <sparclinux@vger.kernel.org>
Subject: Re: [PATCHv4 3/4] sparc64: Avoid irqsave/restore on vio.lock if in_softirq()
Date: Tue, 21 Oct 2014 20:16:12 -0400 [thread overview]
Message-ID: <20141022001612.GB26724@oracle.com> (raw)
In-Reply-To: <5446F291.1030400@oracle.com>
On (10/21/14 18:56), Dave Kleikamp wrote:
> >
> > Is gcc not smart enough to know that this variable isn't used before
> > it's set? (I assume it isn't used elsewhere in this function)
>
> It probably assumes in_softirq() might evaluate differently in the each
> case.
yes, that's what I suspected too. I suppose it is possible
from the compiler's point of view that something in between
might change the result of in_softirq() so that we may be
using an uninit variable in the second call.
anyway, the warning was annoying, and would only numb the
user into ignoring other real issues, so I figured I might
as well silence the warning.
--Sowmini
prev parent reply other threads:[~2014-10-22 0:16 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-10-21 14:16 [PATCHv4 3/4] sparc64: Avoid irqsave/restore on vio.lock if in_softirq() Sowmini Varadhan
2014-10-21 22:35 ` Julian Calaby
2014-10-21 22:39 ` Sowmini Varadhan
2014-10-21 22:42 ` Julian Calaby
2014-10-21 23:56 ` Dave Kleikamp
2014-10-22 0:16 ` Sowmini Varadhan [this message]
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=20141022001612.GB26724@oracle.com \
--to=sowmini.varadhan@oracle.com \
--cc=dave.kleikamp@oracle.com \
--cc=davem@davemloft.net \
--cc=julian.calaby@gmail.com \
--cc=netdev@vger.kernel.org \
--cc=sparclinux@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
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).