netdev - Re: [PATCH net-next v11 1/7] sched: Add Common Applications Kept Enhanced (cake) qdisc

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:   Wed, 16 May 2018 14:02:03 -0400 (EDT)
From:   David Miller <davem@...emloft.net>
To:     toke@...e.dk
Cc:     netdev@...r.kernel.org, cake@...ts.bufferbloat.net
Subject: Re: [PATCH net-next v11 1/7] sched: Add Common Applications Kept
 Enhanced (cake) qdisc

From: Toke Høiland-Jørgensen <toke@...e.dk>
Date: Tue, 15 May 2018 17:12:44 +0200

> +typedef u64 cobalt_time_t;
> +typedef s64 cobalt_tdiff_t;
 ...
> +static cobalt_time_t cobalt_get_time(void)
> +{
> +	return ktime_get_ns();
> +}
> +
> +static u32 cobalt_time_to_us(cobalt_time_t val)
> +{
> +	do_div(val, NSEC_PER_USEC);
> +	return (u32)val;
> +}

If fundamentally you are working with ktime_t values, please use that type
and the associated helpers.

This is a valid argument that using custom typedefs provide documentation
and an aid to understanding, but I think it doesn't serve that purpose
very well here.

So please just use ktime_t throughout instead of this cobalt_time_t
and cobalt_tdiff_t.  And then use helpers like ktime_to_us() which
properly optimize for 64-bit vs. 32-bit hosts.

Thank you.