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From: "Huang\, Ying" <ying.huang@intel.com>
To: "Steven Rostedt \(Red Hat\)" <rostedt@goodmis.org>
Cc: Mengyang Liu <mengyang.liu@intel.com>, "Brandt\,
	Todd E" <todd.e.brandt@intel.com>,
	"linux-kernel\@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Is it possible to use ftrace to measure secondary CPU bootup time
Date: Mon, 24 Jul 2017 13:46:07 +0800	[thread overview]
Message-ID: <874lu2fkv4.fsf@yhuang-dev.intel.com> (raw)

Hi, Steven,

We are working on parallelizing secondary CPU bootup.   So we need to
measure the bootup time of secondary CPU, that is, measure time spent in
smp_init() and its callees.  But we found that ftrace now doesn't
support measure time spent in smp_init() because it is called too early
(before core_initcall()?).  So, do you think it is possible to use
ftrace to measure secondary CPU bootup time?

Thanks,
Huang, Ying

             reply	other threads:[~2017-07-24  5:46 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-07-24  5:46 Huang, Ying [this message]
2017-07-24  9:17 ` Is it possible to use ftrace to measure secondary CPU bootup time Steven Rostedt
2017-07-24 21:40   ` Brandt, Todd E
2017-07-26 21:20     ` Steven Rostedt
2017-07-25  0:34   ` Huang, Ying

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