[RFC 1/2] Pass loops_per_jiffy in and out of calibrate_delay().
From: Holt <holt
Date: Tue Dec 14 2010 - 20:58:55 EST
In order for x86_64 to do the per_cpu loops_per_jiffy calibration in
parallel, we need to make calibrate_delay() no longer depend upon and
modify the global value.
Signed-off-by: Robin Holt <holt@xxxxxxx>
To: Andi Kleen <andi@xxxxxxxxxxxxxx>
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
---
arch/alpha/kernel/smp.c | 2 +-
arch/arm/kernel/smp.c | 2 +-
arch/arm/mach-omap2/clock.c | 2 +-
arch/blackfin/mach-common/smp.c | 2 +-
arch/ia64/kernel/smpboot.c | 2 +-
arch/m32r/kernel/smpboot.c | 2 +-
arch/mips/kernel/smp.c | 2 +-
arch/mn10300/kernel/smp.c | 3 ++-
arch/sh/kernel/smp.c | 2 +-
arch/sparc/kernel/leon_smp.c | 2 +-
arch/sparc/kernel/sun4d_smp.c | 2 +-
arch/sparc/kernel/sun4m_smp.c | 2 +-
arch/x86/kernel/cpu/cyrix.c | 2 +-
arch/x86/kernel/smpboot.c | 2 +-
include/linux/delay.h | 2 +-
init/calibrate.c | 7 ++++---
init/main.c | 2 +-
17 files changed, 21 insertions(+), 19 deletions(-)
Index: parallelize_calibrate_delay/arch/alpha/kernel/smp.c
===================================================================
--- parallelize_calibrate_delay.orig/arch/alpha/kernel/smp.c 2010-12-14 19:03:15.578220745 -0600
+++ parallelize_calibrate_delay/arch/alpha/kernel/smp.c 2010-12-14 19:03:15.714271892 -0600
@@ -156,7 +156,7 @@ smp_callin(void)
calibrate_delay. */
wait_boot_cpu_to_stop(cpuid);
mb();
- calibrate_delay();
+ loops_per_jiffy = calibrate_delay(loops_per_jiffy);
smp_store_cpu_info(cpuid);
/* Allow master to continue only after we written loops_per_jiffy. */
Index: parallelize_calibrate_delay/arch/arm/kernel/smp.c
===================================================================
--- parallelize_calibrate_delay.orig/arch/arm/kernel/smp.c 2010-12-14 19:03:15.578220745 -0600
+++ parallelize_calibrate_delay/arch/arm/kernel/smp.c 2010-12-14 19:03:15.742253845 -0600
@@ -338,7 +338,7 @@ asmlinkage void __cpuinit secondary_star
*/
percpu_timer_setup();
- calibrate_delay();
+ loops_per_jiffy = calibrate_delay(loops_per_jiffy);
smp_store_cpu_info(cpu);
Index: parallelize_calibrate_delay/arch/arm/mach-omap2/clock.c
===================================================================
--- parallelize_calibrate_delay.orig/arch/arm/mach-omap2/clock.c 2010-12-14 19:03:15.578220745 -0600
+++ parallelize_calibrate_delay/arch/arm/mach-omap2/clock.c 2010-12-14 19:03:15.758258926 -0600
@@ -441,7 +441,7 @@ int __init omap2_clk_switch_mpurate_at_b
return -EINVAL;
}
- calibrate_delay();
+ loops_per_jiffy = calibrate_delay(loops_per_jiffy);
recalculate_root_clocks();
clk_put(mpurate_ck);
Index: parallelize_calibrate_delay/arch/blackfin/mach-common/smp.c
===================================================================
--- parallelize_calibrate_delay.orig/arch/blackfin/mach-common/smp.c 2010-12-14 19:03:15.578220745 -0600
+++ parallelize_calibrate_delay/arch/blackfin/mach-common/smp.c 2010-12-14 19:03:15.802314977 -0600
@@ -433,7 +433,7 @@ void __cpuinit secondary_start_kernel(vo
* IRQs need to be enabled here - D-cache can be invalidated
* in timer irq handler, so core B can read correct jiffies.
*/
- calibrate_delay();
+ loops_per_jiffy = calibrate_delay(loops_per_jiffy);
cpu_idle();
}
Index: parallelize_calibrate_delay/arch/ia64/kernel/smpboot.c
===================================================================
--- parallelize_calibrate_delay.orig/arch/ia64/kernel/smpboot.c 2010-12-14 19:03:15.578220745 -0600
+++ parallelize_calibrate_delay/arch/ia64/kernel/smpboot.c 2010-12-14 19:03:15.850311884 -0600
@@ -445,7 +445,7 @@ smp_callin (void)
last_cpuinfo->family != this_cpuinfo->family ||
last_cpuinfo->archrev != this_cpuinfo->archrev ||
last_cpuinfo->model != this_cpuinfo->model)
- calibrate_delay();
+ loops_per_jiffy = calibrate_delay(loops_per_jiffy);
local_cpu_data->loops_per_jiffy = loops_per_jiffy;
/*
Index: parallelize_calibrate_delay/arch/m32r/kernel/smpboot.c
===================================================================
--- parallelize_calibrate_delay.orig/arch/m32r/kernel/smpboot.c 2010-12-14 19:03:15.578220745 -0600
+++ parallelize_calibrate_delay/arch/m32r/kernel/smpboot.c 2010-12-14 19:03:15.890375853 -0600
@@ -498,7 +498,7 @@ static void __init smp_online(void)
local_irq_enable();
/* Get our bogomips. */
- calibrate_delay();
+ loops_per_jiffy = calibrate_delay(loops_per_jiffy);
/* Save our processor parameters */
smp_store_cpu_info(cpu_id);
Index: parallelize_calibrate_delay/arch/mips/kernel/smp.c
===================================================================
--- parallelize_calibrate_delay.orig/arch/mips/kernel/smp.c 2010-12-14 19:03:15.578220745 -0600
+++ parallelize_calibrate_delay/arch/mips/kernel/smp.c 2010-12-14 19:03:15.942375401 -0600
@@ -115,7 +115,7 @@ asmlinkage __cpuinit void start_secondar
* to an option instead of something based on .cputype
*/
- calibrate_delay();
+ loops_per_jiffy = calibrate_delay(loops_per_jiffy);
preempt_disable();
cpu = smp_processor_id();
cpu_data[cpu].udelay_val = loops_per_jiffy;
Index: parallelize_calibrate_delay/arch/mn10300/kernel/smp.c
===================================================================
--- parallelize_calibrate_delay.orig/arch/mn10300/kernel/smp.c 2010-12-14 19:03:15.578220745 -0600
+++ parallelize_calibrate_delay/arch/mn10300/kernel/smp.c 2010-12-14 19:03:16.010251766 -0600
@@ -827,7 +827,8 @@ static void __init smp_callin(void)
}
#ifdef CONFIG_CALIBRATE_DELAY
- calibrate_delay(); /* Get our bogomips */
+ /* Get our bogomips */
+ loops_per_jiffy = calibrate_delay(loops_per_jiffy);
#endif
/* Save our processor parameters */
Index: parallelize_calibrate_delay/arch/sh/kernel/smp.c
===================================================================
--- parallelize_calibrate_delay.orig/arch/sh/kernel/smp.c 2010-12-14 19:03:15.578220745 -0600
+++ parallelize_calibrate_delay/arch/sh/kernel/smp.c 2010-12-14 19:03:16.062800992 -0600
@@ -200,7 +200,7 @@ asmlinkage void __cpuinit start_secondar
/* Enable local timers */
local_timer_setup(cpu);
- calibrate_delay();
+ loops_per_jiffy = calibrate_delay(loops_per_jiffy);
smp_store_cpu_info(cpu);
Index: parallelize_calibrate_delay/arch/sparc/kernel/leon_smp.c
===================================================================
--- parallelize_calibrate_delay.orig/arch/sparc/kernel/leon_smp.c 2010-12-14 19:03:15.578220745 -0600
+++ parallelize_calibrate_delay/arch/sparc/kernel/leon_smp.c 2010-12-14 19:03:16.122794054 -0600
@@ -74,7 +74,7 @@ void __cpuinit leon_callin(void)
/* Get our local ticker going. */
smp_setup_percpu_timer();
- calibrate_delay();
+ loops_per_jiffy = calibrate_delay(loops_per_jiffy);
smp_store_cpu_info(cpuid);
local_flush_cache_all();
Index: parallelize_calibrate_delay/arch/sparc/kernel/sun4d_smp.c
===================================================================
--- parallelize_calibrate_delay.orig/arch/sparc/kernel/sun4d_smp.c 2010-12-14 19:03:15.578220745 -0600
+++ parallelize_calibrate_delay/arch/sparc/kernel/sun4d_smp.c 2010-12-14 19:03:16.226765981 -0600
@@ -109,7 +109,7 @@ void __cpuinit smp4d_callin(void)
/* Get our local ticker going. */
smp_setup_percpu_timer();
- calibrate_delay();
+ loops_per_jiffy = calibrate_delay(loops_per_jiffy);
smp_store_cpu_info(cpuid);
local_flush_cache_all();
local_flush_tlb_all();
Index: parallelize_calibrate_delay/arch/sparc/kernel/sun4m_smp.c
===================================================================
--- parallelize_calibrate_delay.orig/arch/sparc/kernel/sun4m_smp.c 2010-12-14 19:03:15.578220745 -0600
+++ parallelize_calibrate_delay/arch/sparc/kernel/sun4m_smp.c 2010-12-14 19:03:16.270721019 -0600
@@ -78,7 +78,7 @@ void __cpuinit smp4m_callin(void)
/* Get our local ticker going. */
smp_setup_percpu_timer();
- calibrate_delay();
+ loops_per_jiffy = calibrate_delay(loops_per_jiffy);
smp_store_cpu_info(cpuid);
local_flush_cache_all();
Index: parallelize_calibrate_delay/arch/x86/kernel/cpu/cyrix.c
===================================================================
--- parallelize_calibrate_delay.orig/arch/x86/kernel/cpu/cyrix.c 2010-12-14 19:03:15.578220745 -0600
+++ parallelize_calibrate_delay/arch/x86/kernel/cpu/cyrix.c 2010-12-14 19:03:16.350756091 -0600
@@ -105,7 +105,7 @@ static void __cpuinit check_cx686_slop(s
if (ccr5 & 2) { /* possible wrong calibration done */
printk(KERN_INFO "Recalibrating delay loop with SLOP bit reset\n");
- calibrate_delay();
+ loops_per_jiffy = calibrate_delay(loops_per_jiffy);
c->loops_per_jiffy = loops_per_jiffy;
}
}
Index: parallelize_calibrate_delay/arch/x86/kernel/smpboot.c
===================================================================
--- parallelize_calibrate_delay.orig/arch/x86/kernel/smpboot.c 2010-12-14 19:03:15.578220745 -0600
+++ parallelize_calibrate_delay/arch/x86/kernel/smpboot.c 2010-12-14 19:03:16.378379088 -0600
@@ -272,7 +272,7 @@ static void __cpuinit smp_callin(void)
* the NMI watchdog might kill us.
*/
local_irq_enable();
- calibrate_delay();
+ loops_per_jiffy = calibrate_delay(loops_per_jiffy);
local_irq_disable();
pr_debug("Stack at about %p\n", &cpuid);
Index: parallelize_calibrate_delay/include/linux/delay.h
===================================================================
--- parallelize_calibrate_delay.orig/include/linux/delay.h 2010-12-14 19:03:15.578220745 -0600
+++ parallelize_calibrate_delay/include/linux/delay.h 2010-12-14 19:03:16.430247301 -0600
@@ -42,7 +42,7 @@ static inline void ndelay(unsigned long
#endif
extern unsigned long lpj_fine;
-void calibrate_delay(void);
+unsigned long calibrate_delay(unsigned long);
void msleep(unsigned int msecs);
unsigned long msleep_interruptible(unsigned int msecs);
void usleep_range(unsigned long min, unsigned long max);
Index: parallelize_calibrate_delay/init/calibrate.c
===================================================================
--- parallelize_calibrate_delay.orig/init/calibrate.c 2010-12-14 19:03:15.578220745 -0600
+++ parallelize_calibrate_delay/init/calibrate.c 2010-12-14 19:20:53.582472607 -0600
@@ -119,11 +119,12 @@ static unsigned long __cpuinit calibrate
*/
#define LPS_PREC 8
-void __cpuinit calibrate_delay(void)
+unsigned long __cpuinit calibrate_delay(unsigned long loops_per_jiffy)
{
unsigned long ticks, loopbit;
int lps_precision = LPS_PREC;
- static bool printed;
+ static atomic_t n_called = ATOMIC_INIT(0);
+ bool printed = atomic_inc_return(&n_called) != 1;
if (preset_lpj) {
loops_per_jiffy = preset_lpj;
@@ -178,5 +179,5 @@ void __cpuinit calibrate_delay(void)
loops_per_jiffy/(500000/HZ),
(loops_per_jiffy/(5000/HZ)) % 100, loops_per_jiffy);
- printed = true;
+ return loops_per_jiffy;
}
Index: parallelize_calibrate_delay/init/main.c
===================================================================
--- parallelize_calibrate_delay.orig/init/main.c 2010-12-14 19:03:15.578220745 -0600
+++ parallelize_calibrate_delay/init/main.c 2010-12-14 19:03:16.570396588 -0600
@@ -664,7 +664,7 @@ asmlinkage void __init start_kernel(void
if (late_time_init)
late_time_init();
sched_clock_init();
- calibrate_delay();
+ loops_per_jiffy = calibrate_delay(loops_per_jiffy);
pidmap_init();
anon_vma_init();
#ifdef CONFIG_X86
--
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