From mboxrd@z Thu Jan 1 00:00:00 1970 From: tony@atomide.com (Tony Lindgren) Date: Fri, 2 Sep 2011 15:49:46 +0300 Subject: [PATCH v3] ARM: sched_clock: allow sched_clock to be selected at runtime In-Reply-To: <1314712599-12234-1-git-send-email-marc.zyngier@arm.com> References: <1314712599-12234-1-git-send-email-marc.zyngier@arm.com> Message-ID: <20110902124945.GX3548@atomide.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org * Marc Zyngier [110830 16:29]: > sched_clock() is yet another blocker on the road to the single > image. This patch implements an idea by Russell King: > > http://www.spinics.net/lists/linux-omap/msg49561.html > > Instead of asking the platform to implement both sched_clock() > itself and the rollover callback, simply register a read() > function, and let the ARM code care about sched_clock() itself, > the conversion to ns and the rollover. sched_clock() uses > this read() function as an indirection to the platform code. > > This allow some simplifications and possibly some footprint gain > when multiple platforms are compiled in. Among the drawbacks, > the removal of the *_fixed_sched_clock optimization which could > negatively impact some platforms (sa1100, tegra, versatile > and omap). > > Tested on 11MPCore, OMAP4 and Tegra. Great, seems to boot just fine with printk_time :) I gave it a quick boot test on omap16xx, 2420, 3430, 3630 and 4430: Tested-by: Tony Lindgren