From: Thomas Monjalon <thomas.monjalon@6wind.com>
To: "François-Frédéric Ozog" <ff@ozog.com>,
"'Didier Pallard'" <didier.pallard@6wind.com>
Cc: dev@dpdk.org
Subject: Re: [dpdk-dev] [PATCH] timer: add lfence before TSC read
Date: Mon, 27 Jan 2014 10:57:52 +0100 [thread overview]
Message-ID: <201401271057.52251.thomas.monjalon@6wind.com> (raw)
In-Reply-To: <00d201cf18f9$67cdaf10$37690d30$@com>
24/01/2014 12:42, François-Frédéric Ozog:
> IMHO, adding the lfence for all cases is introducing an un-necessary
> performance penalty.
>
> What about adding rte_rdtsc_sync() or rte_rdtsc_serial() with the comment
> about the rdtsc instruction behavior so that developers can choose which
> form they want?
Yes it could be a good idea in some cases. Didier, could you try to add such
function ?
But in some debugging cases we need to have high precision for almost all
timestamps. Here I don't know what is the smartest solution.
Thank you for commenting. Hope we'll find a good fix.
--
Thomas
next prev parent reply other threads:[~2014-01-27 9:56 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-01-24 11:17 Didier Pallard
2014-01-24 11:42 ` François-Frédéric Ozog
2014-01-24 12:48 ` Ananyev, Konstantin
2014-01-27 9:57 ` Thomas Monjalon [this message]
2014-01-27 11:58 ` didier.pallard
2014-01-28 1:28 ` Sangjin Han
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