linux-kernel - Re: [PATCH 1/2] rcu: introduce list_last_or_null

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Thu, 28 May 2015 14:06:17 -0700
From:	"Paul E. McKenney" <paulmck@...ux.vnet.ibm.com>
To:	Dan Streetman <ddstreet@...e.org>
Cc:	Josh Triplett <josh@...htriplett.org>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Steven Rostedt <rostedt@...dmis.org>,
	Mathieu Desnoyers <mathieu.desnoyers@...icios.com>,
	Lai Jiangshan <laijs@...fujitsu.com>,
	linux-kernel <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH 1/2] rcu: introduce list_last_or_null_rcu

On Thu, May 28, 2015 at 04:44:59PM -0400, Dan Streetman wrote:
> On Thu, May 28, 2015 at 4:42 PM, Dan Streetman <ddstreet@...e.org> wrote:
> > On Thu, May 28, 2015 at 4:39 PM,  <josh@...htriplett.org> wrote:
> >> On Thu, May 28, 2015 at 04:35:27PM -0400, Dan Streetman wrote:
> >>> Add list_last_or_null_rcu(), to simplify getting the last entry from a
> >>> rcu-protected list.  The standard list_last_entry() can't be used as it
> >>> is not rcu-protected; the list may be modified concurrently.  And the
> >>> ->prev pointer can't be used, as only the ->next pointers are protected
> >>> by rcu.
> >>>
> >>> This simply iterates forward through the entire list, to get to the last
> >>> entry.  If the list is empty, it returns NULL.
> >>>
> >>> Signed-off-by: Dan Streetman <ddstreet@...e.org>
> >>
> >> The list iteration functions are macros because they introduce a loop
> >> with attached loop block.  For this, is there any reason not to make it
> >> an inline function instead of a macro?
> >
> > true, there's no reason i can see not to make it inline, let me send
> > an updated patch.
> 
> ha, as soon as i sent that email, i realized it can't be an inline
> function, because the return value is (type *), not a predefined
> value.  Of course it could return void*, but unless there's a benefit
> of making it an inline function, it seems to me like it would be
> better as a #define.

Hey, I was hoping...  ;-)

							Thanx, Paul

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/