diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2009-03-26 16:05:01 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2009-03-26 16:05:01 -0700 |
commit | 831576fe40f4175e0767623cffa4aeb28157943a (patch) | |
tree | de54e628e5849d6cf201df4446d760d17f752326 /arch | |
parent | 21cdbc1378e8aa96e1ed4a606dce1a8e7daf7fdf (diff) | |
parent | 66fef08f7d5267b2312c4b48a6d2957d2d414105 (diff) | |
download | lwn-831576fe40f4175e0767623cffa4aeb28157943a.tar.gz lwn-831576fe40f4175e0767623cffa4aeb28157943a.zip |
Merge branch 'sched-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'sched-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (46 commits)
sched: Add comments to find_busiest_group() function
sched: Refactor the power savings balance code
sched: Optimize the !power_savings_balance during fbg()
sched: Create a helper function to calculate imbalance
sched: Create helper to calculate small_imbalance in fbg()
sched: Create a helper function to calculate sched_domain stats for fbg()
sched: Define structure to store the sched_domain statistics for fbg()
sched: Create a helper function to calculate sched_group stats for fbg()
sched: Define structure to store the sched_group statistics for fbg()
sched: Fix indentations in find_busiest_group() using gotos
sched: Simple helper functions for find_busiest_group()
sched: remove unused fields from struct rq
sched: jiffies not printed per CPU
sched: small optimisation of can_migrate_task()
sched: fix typos in documentation
sched: add avg_overlap decay
x86, sched_clock(): mark variables read-mostly
sched: optimize ttwu vs group scheduling
sched: TIF_NEED_RESCHED -> need_reshed() cleanup
sched: don't rebalance if attached on NULL domain
...
Diffstat (limited to 'arch')
-rw-r--r-- | arch/x86/kernel/cpu/intel.c | 8 | ||||
-rw-r--r-- | arch/x86/kernel/tsc.c | 9 |
2 files changed, 12 insertions, 5 deletions
diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c index 24ff26a38ade..5fff00c70de0 100644 --- a/arch/x86/kernel/cpu/intel.c +++ b/arch/x86/kernel/cpu/intel.c @@ -4,6 +4,7 @@ #include <linux/string.h> #include <linux/bitops.h> #include <linux/smp.h> +#include <linux/sched.h> #include <linux/thread_info.h> #include <linux/module.h> @@ -56,11 +57,16 @@ static void __cpuinit early_init_intel(struct cpuinfo_x86 *c) /* * c->x86_power is 8000_0007 edx. Bit 8 is TSC runs at constant rate - * with P/T states and does not stop in deep C-states + * with P/T states and does not stop in deep C-states. + * + * It is also reliable across cores and sockets. (but not across + * cabinets - we turn it off in that case explicitly.) */ if (c->x86_power & (1 << 8)) { set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC); set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC); + set_cpu_cap(c, X86_FEATURE_TSC_RELIABLE); + sched_clock_stable = 1; } } diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c index b8e7aaf7ef75..08afa1579e6d 100644 --- a/arch/x86/kernel/tsc.c +++ b/arch/x86/kernel/tsc.c @@ -17,20 +17,21 @@ #include <asm/delay.h> #include <asm/hypervisor.h> -unsigned int cpu_khz; /* TSC clocks / usec, not used here */ +unsigned int __read_mostly cpu_khz; /* TSC clocks / usec, not used here */ EXPORT_SYMBOL(cpu_khz); -unsigned int tsc_khz; + +unsigned int __read_mostly tsc_khz; EXPORT_SYMBOL(tsc_khz); /* * TSC can be unstable due to cpufreq or due to unsynced TSCs */ -static int tsc_unstable; +static int __read_mostly tsc_unstable; /* native_sched_clock() is called before tsc_init(), so we must start with the TSC soft disabled to prevent erroneous rdtsc usage on !cpu_has_tsc processors */ -static int tsc_disabled = -1; +static int __read_mostly tsc_disabled = -1; static int tsc_clocksource_reliable; /* |