linux-kernel - Re: [PATCH 3/8] Add a PF flag for ksoftirqd identification

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]

Message-ID: <1287153988.2647.68.camel@edumazet-laptop>
Date:	Fri, 15 Oct 2010 16:46:28 +0200
From:	Eric Dumazet <eric.dumazet@...il.com>
To:	Venkatesh Pallipadi <venki@...gle.com>
Cc:	Peter Zijlstra <peterz@...radead.org>, Ingo Molnar <mingo@...e.hu>,
	"H. Peter Anvin" <hpa@...or.com>,
	Thomas Gleixner <tglx@...utronix.de>,
	Balbir Singh <balbir@...ux.vnet.ibm.com>,
	Martin Schwidefsky <schwidefsky@...ibm.com>,
	linux-kernel@...r.kernel.org, Paul Turner <pjt@...gle.com>
Subject: Re: [PATCH 3/8] Add a PF flag for ksoftirqd identification

Le lundi 04 octobre 2010 à 17:03 -0700, Venkatesh Pallipadi a écrit :
> To account softirq time cleanly in scheduler, we need to identify whether
> softirq is invoked in ksoftirqd context or softirq at hardirq tail context.
> Add PF_KSOFTIRQD for that purpose.
> 
> As all PF flag bits are currently taken, create space by moving one of the
> infrequently used bits (PF_THREAD_BOUND) down in task_struct to be along
> with some other state fields.
> 
> Signed-off-by: Venkatesh Pallipadi <venki@...gle.com>

Instead of using one bit per task (and fight to find a free bit) why not
using existing :

DEFINE_PER_CPU(struct task_struct *, ksoftirqd);

And check if current is ksoftirqd ?

if (__get_cpu_var(ksoftirqd) == current) ...


--
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/