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From: Thomas Gleixner <tglx@linutronix.de>
To: LKML <linux-kernel@vger.kernel.org>
Cc: Linus Torvalds <torvalds@osdl.org>, Ingo Molnar <mingo@elte.hu>,
	Alok Kataria <akataria@vmware.com>,
	Arjan van de Veen <arjan@infradead.org>
Subject: [RFC patch 3/4] x86: TSC: use one set of reference variables
Date: Thu, 04 Sep 2008 15:18:53 -0000	[thread overview]
Message-ID: <20080904151249.729279624@linutronix.de> (raw)
In-Reply-To: <20080904150339.896115280@linutronix.de>

[-- Attachment #1: tsc-use-one-set-of-ref-variables.patch --]
[-- Type: text/plain, Size: 2933 bytes --]

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
 arch/x86/kernel/tsc.c |   22 +++++++++++-----------
 1 file changed, 11 insertions(+), 11 deletions(-)

Index: linux-2.6/arch/x86/kernel/tsc.c
===================================================================
--- linux-2.6.orig/arch/x86/kernel/tsc.c
+++ linux-2.6/arch/x86/kernel/tsc.c
@@ -104,7 +104,7 @@ __setup("notsc", notsc_setup);
 /*
  * Read TSC and the reference counters. Take care of SMI disturbance
  */
-static u64 tsc_read_refs(u64 *pm, u64 *hpet)
+static u64 tsc_read_refs(u64 *p, int hpet)
 {
 	u64 t1, t2;
 	int i;
@@ -112,9 +112,9 @@ static u64 tsc_read_refs(u64 *pm, u64 *h
 	for (i = 0; i < MAX_RETRIES; i++) {
 		t1 = get_cycles();
 		if (hpet)
-			*hpet = hpet_readl(HPET_COUNTER) & 0xFFFFFFFF;
+			*p = hpet_readl(HPET_COUNTER) & 0xFFFFFFFF;
 		else
-			*pm = acpi_pm_read_early();
+			*p = acpi_pm_read_early();
 		t2 = get_cycles();
 		if ((t2 - t1) < SMI_TRESHOLD)
 			return t2;
@@ -228,7 +228,7 @@ static unsigned long pit_calibrate_tsc(v
  */
 unsigned long native_calibrate_tsc(void)
 {
-	u64 tsc1, tsc2, delta, pm1, pm2, hpet1, hpet2;
+	u64 tsc1, tsc2, delta, ref1, ref2;
 	unsigned long tsc_pit_min = ULONG_MAX, tsc_ref_min = ULONG_MAX;
 	unsigned long flags;
 	int hpet = is_hpet_enabled(), i;
@@ -267,16 +267,16 @@ unsigned long native_calibrate_tsc(void)
 		 * read the end value.
 		 */
 		local_irq_save(flags);
-		tsc1 = tsc_read_refs(&pm1, hpet ? &hpet1 : NULL);
+		tsc1 = tsc_read_refs(&ref1, hpet);
 		tsc_pit_khz = pit_calibrate_tsc();
-		tsc2 = tsc_read_refs(&pm2, hpet ? &hpet2 : NULL);
+		tsc2 = tsc_read_refs(&ref2, hpet);
 		local_irq_restore(flags);
 
 		/* Pick the lowest PIT TSC calibration so far */
 		tsc_pit_min = min(tsc_pit_min, tsc_pit_khz);
 
 		/* hpet or pmtimer available ? */
-		if (!hpet && !pm1 && !pm2)
+		if (!hpet && !ref1 && !ref2)
 			continue;
 
 		/* Check, whether the sampling was disturbed by an SMI */
@@ -285,9 +285,9 @@ unsigned long native_calibrate_tsc(void)
 
 		tsc2 = (tsc2 - tsc1) * 1000000LL;
 		if (hpet)
-			tsc2 = calc_hpet_ref(tsc2, hpet1, hpet2);
+			tsc2 = calc_hpet_ref(tsc2, ref1, ref2);
 		else
-			tsc2 = calc_pmtimer_ref(tsc2, pm1, pm2);
+			tsc2 = calc_pmtimer_ref(tsc2, ref1, ref2);
 
 		tsc_ref_min = min(tsc_ref_min, (unsigned long) tsc2);
 	}
@@ -300,7 +300,7 @@ unsigned long native_calibrate_tsc(void)
 		printk(KERN_WARNING "TSC: Unable to calibrate against PIT\n");
 
 		/* We don't have an alternative source, disable TSC */
-		if (!hpet && !pm1 && !pm2) {
+		if (!hpet && !ref1 && !ref2) {
 			printk("TSC: No reference (HPET/PMTIMER) available\n");
 			return 0;
 		}
@@ -320,7 +320,7 @@ unsigned long native_calibrate_tsc(void)
 	}
 
 	/* We don't have an alternative source, use the PIT calibration value */
-	if (!hpet && !pm1 && !pm2) {
+	if (!hpet && !ref1 && !ref2) {
 		printk(KERN_INFO "TSC: Using PIT calibration value\n");
 		return tsc_pit_min;
 	}

-- 


  parent reply	other threads:[~2008-09-04 15:20 UTC|newest]

Thread overview: 52+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-09-04 15:18 [RFC patch 0/4] TSC calibration improvements Thomas Gleixner
2008-09-04 15:18 ` [RFC patch 1/4] x86: TSC: define the PIT latch value separate Thomas Gleixner
2008-09-04 15:18 ` [RFC patch 2/4] x86: TSC: separate hpet/pmtimer calculation out Thomas Gleixner
2008-09-04 15:18 ` Thomas Gleixner [this message]
2008-09-04 15:18 ` [RFC patch 4/4] x86: TSC make the calibration loop smarter Thomas Gleixner
2008-09-04 15:36 ` [RFC patch 0/4] TSC calibration improvements Ingo Molnar
2008-09-04 15:45   ` Linus Torvalds
2008-09-04 16:00     ` Ingo Molnar
2008-09-04 16:21       ` Linus Torvalds
2008-09-04 16:36         ` Ingo Molnar
2008-09-04 17:41         ` Linus Torvalds
2008-09-04 18:07           ` Alan Cox
2008-09-04 18:26             ` Linus Torvalds
2008-09-04 18:30               ` H. Peter Anvin
2008-09-04 20:09               ` Linus Torvalds
2008-09-04 20:43                 ` Ingo Molnar
2008-09-04 20:52                   ` Ingo Molnar
2008-09-04 21:09                     ` Linus Torvalds
2008-09-04 21:21                       ` Ingo Molnar
2008-09-04 21:30                         ` Linus Torvalds
2008-09-04 21:34                           ` Linus Torvalds
2008-09-04 21:39                             ` Ingo Molnar
2008-09-04 21:33                       ` Ingo Molnar
2008-09-05 22:18                         ` Alok Kataria
2008-09-05 22:34                           ` Linus Torvalds
2008-09-06 20:03                             ` Thomas Gleixner
2008-09-06 20:29                               ` Linus Torvalds
2008-09-06 20:37                                 ` Thomas Gleixner
2008-09-06 20:50                                   ` Linus Torvalds
2008-09-06 20:55                                     ` Linus Torvalds
2008-09-06 21:15                                       ` Thomas Gleixner
2008-09-06 21:22                                         ` Linus Torvalds
2008-09-06 21:30                                           ` Thomas Gleixner
2008-09-06 22:40                                       ` Ingo Molnar
2008-09-06 20:58                                     ` Thomas Gleixner
2008-09-06 21:10                                       ` Linus Torvalds
2008-09-07  6:01                                         ` Willy Tarreau
2008-09-06 20:52                                   ` Thomas Gleixner
2008-09-06 20:59                                     ` Linus Torvalds
2008-09-06 21:07                                       ` Thomas Gleixner
2008-09-06 21:15                                         ` Linus Torvalds
2008-09-06 21:26                                           ` Thomas Gleixner
2008-09-06 21:32                                             ` Linus Torvalds
2008-09-04 20:53                   ` Linus Torvalds
2008-09-04 21:38                 ` Alok Kataria
2008-09-04 21:52                   ` Linus Torvalds
2008-09-04 22:09                     ` Alok Kataria
2008-09-04 17:39     ` Alok Kataria
2008-09-04 17:53       ` Linus Torvalds
2008-09-04 18:31         ` Alok Kataria
2008-09-04 18:34           ` H. Peter Anvin
2008-09-04 21:00   ` Valdis.Kletnieks

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