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From: Thomas Gleixner <tglx@linutronix.de>
To: Stanislav Fomichev <stfomichev@yandex-team.ru>
Cc: viresh.kumar@linaro.org, paul.gortmaker@windriver.com,
	peterz@infradead.org, stuart.w.hayes@gmail.com,
	david.vrabel@citrix.com, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] hrtimers: conditionally lock/unlock spinlock in hrtimer_get_next_event
Date: Mon, 9 Jun 2014 13:06:48 +0200 (CEST)	[thread overview]
Message-ID: <alpine.DEB.2.10.1406091304140.3830@nanos> (raw)
In-Reply-To: <1402305825-3015-1-git-send-email-stfomichev@yandex-team.ru>

On Mon, 9 Jun 2014, Stanislav Fomichev wrote:

> In hrtimer_get_next_event we unconditionally lock/unlock spinlock, even if it's
> not required (hrtimer_hres_active() != 0). This patch moves
> locking/unlocking and mindelta range check inside the if clause,
> so we don't execute unnecessary operations.

What's wrong with simply doing:

       if (!hrtimer_hres_active())
       	  return mindelta;

That saves and indentation level and makes the code more
readable. Also the lockless check wants a comment why it is correct.

Thanks,

	tglx

  parent reply	other threads:[~2014-06-09 11:07 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-06-09  9:23 [PATCH] hrtimers: conditionally lock/unlock spinlock in hrtimer_get_next_event Stanislav Fomichev
2014-06-09  9:27 ` Viresh Kumar
2014-06-09 11:06 ` Thomas Gleixner [this message]
2014-06-09 11:11   ` Stanislav Fomichev
2014-06-09 12:59     ` [PATCH v2] hrtimers: add fast path to hrtimer_get_next_event Stanislav Fomichev
2014-06-09 13:28       ` Viresh Kumar
2014-06-10  7:42         ` Peter Zijlstra
2014-06-09 14:44       ` Thomas Gleixner
2014-06-10  9:46         ` [PATCH v3] " Stanislav Fomichev

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