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author | Alok Kataria <akataria@vmware.com> | 2008-06-23 18:21:56 -0700 |
---|---|---|
committer | Ingo Molnar <mingo@elte.hu> | 2008-06-24 13:53:46 +0200 |
commit | f3f3149f35b9195ef4b761b1353fc0766b5f53be (patch) | |
tree | 96e67c82e8ea6ce57ce5f83a8036f87a8d534867 | |
parent | 6ff10de374cc68ff2024247793176dc8a1b317ea (diff) | |
download | op-kernel-dev-f3f3149f35b9195ef4b761b1353fc0766b5f53be.zip op-kernel-dev-f3f3149f35b9195ef4b761b1353fc0766b5f53be.tar.gz |
x86: use cpu_khz for loops_per_jiffy calculation, cleanup
As suggested by Ingo, remove all references to tsc from init/calibrate.c
TSC is x86 specific, and using tsc in variable names in a generic file should
be avoided. lpj_tsc is now called lpj_fine, since it is related to fine tuning
of lpj value. Also tsc_rate_* is called timer_rate_*
Signed-off-by: Alok N Kataria <akataria@vmware.com>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Daniel Hecht <dhecht@vmware.com>
Cc: Tim Mann <mann@vmware.com>
Cc: Zach Amsden <zach@vmware.com>
Cc: Sahil Rihan <srihan@vmware.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
-rw-r--r-- | arch/x86/kernel/time_64.c | 2 | ||||
-rw-r--r-- | arch/x86/kernel/tsc_32.c | 2 | ||||
-rw-r--r-- | include/linux/delay.h | 2 | ||||
-rw-r--r-- | init/calibrate.c | 36 |
4 files changed, 22 insertions, 20 deletions
diff --git a/arch/x86/kernel/time_64.c b/arch/x86/kernel/time_64.c index 12b4a71..39ae851 100644 --- a/arch/x86/kernel/time_64.c +++ b/arch/x86/kernel/time_64.c @@ -123,7 +123,7 @@ void __init time_init(void) (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)) cpu_khz = calculate_cpu_khz(); - lpj_tsc = ((unsigned long)tsc_khz * 1000)/HZ; + lpj_fine = ((unsigned long)tsc_khz * 1000)/HZ; if (unsynchronized_tsc()) mark_tsc_unstable("TSCs unsynchronized"); diff --git a/arch/x86/kernel/tsc_32.c b/arch/x86/kernel/tsc_32.c index 0af49fb..048baab 100644 --- a/arch/x86/kernel/tsc_32.c +++ b/arch/x86/kernel/tsc_32.c @@ -425,7 +425,7 @@ void __init tsc_init(void) lpj = ((u64)tsc_khz * 1000); do_div(lpj, HZ); - lpj_tsc = lpj; + lpj_fine = lpj; printk("Detected %lu.%03lu MHz processor.\n", (unsigned long)cpu_khz / 1000, diff --git a/include/linux/delay.h b/include/linux/delay.h index 01aec60..fd832c6 100644 --- a/include/linux/delay.h +++ b/include/linux/delay.h @@ -41,7 +41,7 @@ static inline void ndelay(unsigned long x) #define ndelay(x) ndelay(x) #endif -extern unsigned long lpj_tsc; +extern unsigned long lpj_fine; void calibrate_delay(void); void msleep(unsigned int msecs); unsigned long msleep_interruptible(unsigned int msecs); diff --git a/init/calibrate.c b/init/calibrate.c index 8628697..7963e3f 100644 --- a/init/calibrate.c +++ b/init/calibrate.c @@ -10,7 +10,7 @@ #include <linux/timex.h> #include <linux/smp.h> -unsigned long lpj_tsc; +unsigned long lpj_fine; unsigned long preset_lpj; static int __init lpj_setup(char *str) { @@ -35,9 +35,9 @@ static unsigned long __cpuinit calibrate_delay_direct(void) unsigned long pre_start, start, post_start; unsigned long pre_end, end, post_end; unsigned long start_jiffies; - unsigned long tsc_rate_min, tsc_rate_max; - unsigned long good_tsc_sum = 0; - unsigned long good_tsc_count = 0; + unsigned long timer_rate_min, timer_rate_max; + unsigned long good_timer_sum = 0; + unsigned long good_timer_count = 0; int i; if (read_current_timer(&pre_start) < 0 ) @@ -81,22 +81,24 @@ static unsigned long __cpuinit calibrate_delay_direct(void) } read_current_timer(&post_end); - tsc_rate_max = (post_end - pre_start) / DELAY_CALIBRATION_TICKS; - tsc_rate_min = (pre_end - post_start) / DELAY_CALIBRATION_TICKS; + timer_rate_max = (post_end - pre_start) / + DELAY_CALIBRATION_TICKS; + timer_rate_min = (pre_end - post_start) / + DELAY_CALIBRATION_TICKS; /* - * If the upper limit and lower limit of the tsc_rate is + * If the upper limit and lower limit of the timer_rate is * >= 12.5% apart, redo calibration. */ if (pre_start != 0 && pre_end != 0 && - (tsc_rate_max - tsc_rate_min) < (tsc_rate_max >> 3)) { - good_tsc_count++; - good_tsc_sum += tsc_rate_max; + (timer_rate_max - timer_rate_min) < (timer_rate_max >> 3)) { + good_timer_count++; + good_timer_sum += timer_rate_max; } } - if (good_tsc_count) - return (good_tsc_sum/good_tsc_count); + if (good_timer_count) + return (good_timer_sum/good_timer_count); printk(KERN_WARNING "calibrate_delay_direct() failed to get a good " "estimate for loops_per_jiffy.\nProbably due to long platform interrupts. Consider using \"lpj=\" boot option.\n"); @@ -111,8 +113,8 @@ static unsigned long __cpuinit calibrate_delay_direct(void) {return 0;} * bit takes on average 1.5/HZ seconds. This (like the original) is a little * better than 1% * For the boot cpu we can skip the delay calibration and assign it a value - * calculated based on the tsc frequency. - * For the rest of the CPUs we cannot assume that the tsc frequency is same as + * calculated based on the timer frequency. + * For the rest of the CPUs we cannot assume that the timer frequency is same as * the cpu frequency, hence do the calibration for those. */ #define LPS_PREC 8 @@ -126,11 +128,11 @@ void __cpuinit calibrate_delay(void) loops_per_jiffy = preset_lpj; printk(KERN_INFO "Calibrating delay loop (skipped) preset value.. "); - } else if ((smp_processor_id() == 0) && lpj_tsc) { - loops_per_jiffy = lpj_tsc; + } else if ((smp_processor_id() == 0) && lpj_fine) { + loops_per_jiffy = lpj_fine; printk(KERN_INFO "Calibrating delay loop (skipped), " - "using tsc calculated value.. "); + "value calculated using timer frequency.. "); } else if ((loops_per_jiffy = calibrate_delay_direct()) != 0) { printk(KERN_INFO "Calibrating delay using timer specific routine.. "); |