From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from pythia.bakeyournoodle.com (pythia.bakeyournoodle.com [203.82.209.197]) by ozlabs.org (Postfix) with ESMTP id D22D5DDE0D for ; Mon, 17 Mar 2008 16:23:30 +1100 (EST) Date: Mon, 17 Mar 2008 16:23:29 +1100 To: Paul Mackerras , LinuxPPC-dev Subject: [PATCH 2.6.26] Update wait_state_cycles in the VPA. Message-ID: <20080317052329.GJ6887@bakeyournoodle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 From: tony@bakeyournoodle.com (Tony Breeds) List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , The hypervisor can look at the value in wait_state_cycles for an estimate of how busy dedicated processors are. Currently as the kernel never touches this field so we appear to be 100% busy. Record the duration the kernel is in powersave and pass that to the HV to provide a reasonable indication of utilisation. Signed-off-by: Tony Breeds --- arch/powerpc/platforms/pseries/setup.c | 4 ++++ 1 files changed, 4 insertions(+), 0 deletions(-) diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c index fdb9b1c..90555a3 100644 --- a/arch/powerpc/platforms/pseries/setup.c +++ b/arch/powerpc/platforms/pseries/setup.c @@ -393,6 +393,7 @@ static void pseries_dedicated_idle_sleep(void) { unsigned int cpu = smp_processor_id(); unsigned long start_snooze; + unsigned long in_purr, out_purr; /* * Indicate to the HV that we are idle. Now would be @@ -400,6 +401,7 @@ static void pseries_dedicated_idle_sleep(void) */ get_lppaca()->idle = 1; get_lppaca()->donate_dedicated_cpu = 1; + in_purr = mfspr(SPRN_PURR); /* * We come in with interrupts disabled, and need_resched() @@ -432,6 +434,8 @@ static void pseries_dedicated_idle_sleep(void) out: HMT_medium(); + out_purr = mfspr(SPRN_PURR); + get_lppaca()->wait_state_cycles += out_purr - in_purr; get_lppaca()->donate_dedicated_cpu = 0; get_lppaca()->idle = 0; } -- 1.5.4.3 Yours Tony linux.conf.au http://www.marchsouth.org/ Jan 19 - 24 2009 The Australian Linux Technical Conference!