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Diffstat (limited to 'arch/x86/kernel/tsc.c')
-rw-r--r--arch/x86/kernel/tsc.c34
1 files changed, 19 insertions, 15 deletions
diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c
index 15f97c0abc..5a69a49acc 100644
--- a/arch/x86/kernel/tsc.c
+++ b/arch/x86/kernel/tsc.c
@@ -53,7 +53,7 @@ static int __read_mostly tsc_force_recalibrate;
static u32 art_to_tsc_numerator;
static u32 art_to_tsc_denominator;
static u64 art_to_tsc_offset;
-static struct clocksource *art_related_clocksource;
+static bool have_art;
struct cyc2ns {
struct cyc2ns_data data[2]; /* 0 + 2*16 = 32 */
@@ -652,7 +652,7 @@ success:
}
/**
- * native_calibrate_tsc
+ * native_calibrate_tsc - determine TSC frequency
* Determine TSC frequency via CPUID, else return 0.
*/
unsigned long native_calibrate_tsc(void)
@@ -1168,6 +1168,7 @@ static struct clocksource clocksource_tsc_early = {
.mask = CLOCKSOURCE_MASK(64),
.flags = CLOCK_SOURCE_IS_CONTINUOUS |
CLOCK_SOURCE_MUST_VERIFY,
+ .id = CSID_X86_TSC_EARLY,
.vdso_clock_mode = VDSO_CLOCKMODE_TSC,
.enable = tsc_cs_enable,
.resume = tsc_resume,
@@ -1190,6 +1191,7 @@ static struct clocksource clocksource_tsc = {
CLOCK_SOURCE_VALID_FOR_HRES |
CLOCK_SOURCE_MUST_VERIFY |
CLOCK_SOURCE_VERIFY_PERCPU,
+ .id = CSID_X86_TSC,
.vdso_clock_mode = VDSO_CLOCKMODE_TSC,
.enable = tsc_cs_enable,
.resume = tsc_resume,
@@ -1309,8 +1311,10 @@ struct system_counterval_t convert_art_to_tsc(u64 art)
do_div(tmp, art_to_tsc_denominator);
res += tmp + art_to_tsc_offset;
- return (struct system_counterval_t) {.cs = art_related_clocksource,
- .cycles = res};
+ return (struct system_counterval_t) {
+ .cs_id = have_art ? CSID_X86_TSC : CSID_GENERIC,
+ .cycles = res,
+ };
}
EXPORT_SYMBOL(convert_art_to_tsc);
@@ -1327,12 +1331,10 @@ EXPORT_SYMBOL(convert_art_to_tsc);
* that this flag is set before conversion to TSC is attempted.
*
* Return:
- * struct system_counterval_t - system counter value with the pointer to the
- * corresponding clocksource
- * @cycles: System counter value
- * @cs: Clocksource corresponding to system counter value. Used
- * by timekeeping code to verify comparability of two cycle
- * values.
+ * struct system_counterval_t - system counter value with the ID of the
+ * corresponding clocksource:
+ * cycles: System counter value
+ * cs_id: The clocksource ID for validating comparability
*/
struct system_counterval_t convert_art_ns_to_tsc(u64 art_ns)
@@ -1347,8 +1349,10 @@ struct system_counterval_t convert_art_ns_to_tsc(u64 art_ns)
do_div(tmp, USEC_PER_SEC);
res += tmp;
- return (struct system_counterval_t) { .cs = art_related_clocksource,
- .cycles = res};
+ return (struct system_counterval_t) {
+ .cs_id = have_art ? CSID_X86_TSC : CSID_GENERIC,
+ .cycles = res,
+ };
}
EXPORT_SYMBOL(convert_art_ns_to_tsc);
@@ -1357,7 +1361,7 @@ static void tsc_refine_calibration_work(struct work_struct *work);
static DECLARE_DELAYED_WORK(tsc_irqwork, tsc_refine_calibration_work);
/**
* tsc_refine_calibration_work - Further refine tsc freq calibration
- * @work - ignored.
+ * @work: ignored.
*
* This functions uses delayed work over a period of a
* second to further refine the TSC freq value. Since this is
@@ -1455,7 +1459,7 @@ out:
goto unreg;
if (boot_cpu_has(X86_FEATURE_ART))
- art_related_clocksource = &clocksource_tsc;
+ have_art = true;
clocksource_register_khz(&clocksource_tsc, tsc_khz);
unreg:
clocksource_unregister(&clocksource_tsc_early);
@@ -1481,7 +1485,7 @@ static int __init init_tsc_clocksource(void)
*/
if (boot_cpu_has(X86_FEATURE_TSC_KNOWN_FREQ)) {
if (boot_cpu_has(X86_FEATURE_ART))
- art_related_clocksource = &clocksource_tsc;
+ have_art = true;
clocksource_register_khz(&clocksource_tsc, tsc_khz);
clocksource_unregister(&clocksource_tsc_early);