static_branch_enable(&__use_tsc) may be called twice in common case, that
is redundant. And there are also some common functions both in
tsc_early_init() and tsc_init().
Move them into a separate helper function, only call it once.
Also fix comments:
-s/authorative/authoritative
-s/cyc2ns_init/tsc_init
Cc: Thomas Gleixner <t...@linutronix.de>
Cc: Ingo Molnar <mi...@redhat.com>
Cc: "H. Peter Anvin" <h...@zytor.com>
Cc: Peter Zijlstra <pet...@infradead.org>
Cc: Pavel Tatashin <pasha.tatas...@oracle.com>
Signed-off-by: Dou Liyang <douly.f...@cn.fujitsu.com>
---
arch/x86/kernel/tsc.c | 22 ++++++++++++----------
1 file changed, 12 insertions(+), 10 deletions(-)
diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c
index 02e416b87ac1..ba0a6b6e0726 100644
--- a/arch/x86/kernel/tsc.c
+++ b/arch/x86/kernel/tsc.c
@@ -182,7 +182,7 @@ static void __init cyc2ns_init_boot_cpu(void)
}
/*
- * Secondary CPUs do not run through cyc2ns_init(), so set up
+ * Secondary CPUs do not run through tsc_init(), so set up
* all the scale factors for all CPUs, assuming the same
* speed as the bootup CPU. (cpufreq notifiers will fix this
* up if their speed diverges)
@@ -1389,7 +1389,7 @@ static bool __init determine_cpu_tsc_frequencies(bool
early)
}
/*
- * Trust non-zero tsc_khz as authorative,
+ * Trust non-zero tsc_khz as authoritative,
* and use it to sanity check cpu_khz,
* which will be off if system timer is off.
*/
@@ -1421,6 +1421,14 @@ static unsigned long __init get_loops_per_jiffy(void)
return lpj;
}
+static void __init enable_use_tsc(void)
+{
+ /* Sanitize TSC ADJUST before cyc2ns gets initialized */
+ tsc_store_and_check_tsc_adjust(true);
+ cyc2ns_init_boot_cpu();
+ static_branch_enable(&__use_tsc);
+}
+
void __init tsc_early_init(void)
{
if (!boot_cpu_has(X86_FEATURE_TSC))
@@ -1429,10 +1437,7 @@ void __init tsc_early_init(void)
return;
loops_per_jiffy = get_loops_per_jiffy();
- /* Sanitize TSC ADJUST before cyc2ns gets initialized */
- tsc_store_and_check_tsc_adjust(true);
- cyc2ns_init_boot_cpu();
- static_branch_enable(&__use_tsc);
+ enable_use_tsc();
}
void __init tsc_init(void)
@@ -1456,13 +1461,10 @@ void __init tsc_init(void)
setup_clear_cpu_cap(X86_FEATURE_TSC_DEADLINE_TIMER);
return;
}
- /* Sanitize TSC ADJUST before cyc2ns gets initialized */
- tsc_store_and_check_tsc_adjust(true);
- cyc2ns_init_boot_cpu();
+ enable_use_tsc();
}
cyc2ns_init_secondary_cpus();
- static_branch_enable(&__use_tsc);
if (!no_sched_irq_time)
enable_sched_clock_irqtime();
--
2.14.3
