linux-kernel - Re: [RFC][PATCH] sched/wait_bit: Introduce wait_var_event()/wake_up

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, 15 Mar 2018 14:45:20 +0000
From:   David Howells <dhowells@...hat.com>
To:     Peter Zijlstra <peterz@...radead.org>
Cc:     dhowells@...hat.com, Dan Williams <dan.j.williams@...el.com>,
        linux-nvdimm <linux-nvdimm@...ts.01.org>,
        Ingo Molnar <mingo@...hat.com>, Christoph Hellwig <hch@....de>,
        david <david@...morbit.com>,
        linux-xfs <linux-xfs@...r.kernel.org>,
        linux-fsdevel <linux-fsdevel@...r.kernel.org>,
        Jan Kara <jack@...e.cz>,
        Ross Zwisler <ross.zwisler@...ux.intel.com>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        Ralf Baechle <ralf@...ux-mips.org>
Subject: Re: [RFC][PATCH] sched/wait_bit: Introduce wait_var_event()/wake_up_var()

Peter Zijlstra <peterz@...radead.org> wrote:

> Does the below address things sufficiently clear?

Yep.

> +wait_queue_head_t *__var_waitqueue(void *p)
> +{
> +	if (BITS_PER_LONG == 64) {
> +		unsigned long q = (unsigned long)p;
> +
> +		return bit_waitqueue((void *)(q & ~1), q & 1);
> +	}
> +	return bit_waitqueue(p, 0);
> +}

You might be better off not using bit_waitqueue() but rather do the
calculation directly since you don't actually have a bit number.

David