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Subject[GIT PULL] x86/timers changes for v4.17
Linus,

Please pull the latest x86-timers-for-linus git tree from:

git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git x86-timers-for-linus

# HEAD: ea89c065482179b2bf9f9b6788b06a6e0c68a73b x86/tsc: Get rid of rdtscll()

Two changes: add the new convert_art_ns_to_tsc() API for upcoming Intel Goldmont+
drivers, and remove the obsolete rdtscll() API.


Thanks,

Ingo

------------------>
Rajvi Jingar (1):
x86/tsc: Convert ART in nanoseconds to TSC

Thomas Gleixner (1):
x86/tsc: Get rid of rdtscll()


arch/x86/events/msr.c | 3 ++-
arch/x86/include/asm/msr.h | 3 ---
arch/x86/include/asm/tsc.h | 1 +
arch/x86/kernel/cpu/mcheck/mce-inject.c | 2 +-
arch/x86/kernel/tsc.c | 39 +++++++++++++++++++++++++++++++++
5 files changed, 43 insertions(+), 5 deletions(-)

diff --git a/arch/x86/events/msr.c b/arch/x86/events/msr.c
index 18e2628e2d8f..e7edf19e64c2 100644
--- a/arch/x86/events/msr.c
+++ b/arch/x86/events/msr.c
@@ -188,10 +188,11 @@ static inline u64 msr_read_counter(struct perf_event *event)
if (event->hw.event_base)
rdmsrl(event->hw.event_base, now);
else
- rdtscll(now);
+ now = rdtsc_ordered();

return now;
}
+
static void msr_event_update(struct perf_event *event)
{
u64 prev, now;
diff --git a/arch/x86/include/asm/msr.h b/arch/x86/include/asm/msr.h
index 30df295f6d94..392f05d57e78 100644
--- a/arch/x86/include/asm/msr.h
+++ b/arch/x86/include/asm/msr.h
@@ -218,9 +218,6 @@ static __always_inline unsigned long long rdtsc_ordered(void)
return rdtsc();
}

-/* Deprecated, keep it for a cycle for easier merging: */
-#define rdtscll(now) do { (now) = rdtsc_ordered(); } while (0)
-
static inline unsigned long long native_read_pmc(int counter)
{
DECLARE_ARGS(val, low, high);
diff --git a/arch/x86/include/asm/tsc.h b/arch/x86/include/asm/tsc.h
index cf5d53c3f9ea..2701d221583a 100644
--- a/arch/x86/include/asm/tsc.h
+++ b/arch/x86/include/asm/tsc.h
@@ -31,6 +31,7 @@ static inline cycles_t get_cycles(void)
}

extern struct system_counterval_t convert_art_to_tsc(u64 art);
+extern struct system_counterval_t convert_art_ns_to_tsc(u64 art_ns);

extern void tsc_early_delay_calibrate(void);
extern void tsc_init(void);
diff --git a/arch/x86/kernel/cpu/mcheck/mce-inject.c b/arch/x86/kernel/cpu/mcheck/mce-inject.c
index 231ad23b24a9..475cb4f5f14f 100644
--- a/arch/x86/kernel/cpu/mcheck/mce-inject.c
+++ b/arch/x86/kernel/cpu/mcheck/mce-inject.c
@@ -491,7 +491,7 @@ static void do_inject(void)
unsigned int cpu = i_mce.extcpu;
u8 b = i_mce.bank;

- rdtscll(i_mce.tsc);
+ i_mce.tsc = rdtsc_ordered();

if (i_mce.misc)
i_mce.status |= MCI_STATUS_MISCV;
diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c
index fb4302738410..ef32297ff17e 100644
--- a/arch/x86/kernel/tsc.c
+++ b/arch/x86/kernel/tsc.c
@@ -1179,6 +1179,45 @@ struct system_counterval_t convert_art_to_tsc(u64 art)
}
EXPORT_SYMBOL(convert_art_to_tsc);

+/**
+ * convert_art_ns_to_tsc() - Convert ART in nanoseconds to TSC.
+ * @art_ns: ART (Always Running Timer) in unit of nanoseconds
+ *
+ * PTM requires all timestamps to be in units of nanoseconds. When user
+ * software requests a cross-timestamp, this function converts system timestamp
+ * to TSC.
+ *
+ * This is valid when CPU feature flag X86_FEATURE_TSC_KNOWN_FREQ is set
+ * indicating the tsc_khz is derived from CPUID[15H]. Drivers should check
+ * 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 comparibility of two cycle
+ * values.
+ */
+
+struct system_counterval_t convert_art_ns_to_tsc(u64 art_ns)
+{
+ u64 tmp, res, rem;
+
+ rem = do_div(art_ns, USEC_PER_SEC);
+
+ res = art_ns * tsc_khz;
+ tmp = rem * tsc_khz;
+
+ do_div(tmp, USEC_PER_SEC);
+ res += tmp;
+
+ return (struct system_counterval_t) { .cs = art_related_clocksource,
+ .cycles = res};
+}
+EXPORT_SYMBOL(convert_art_ns_to_tsc);
+
+
static void tsc_refine_calibration_work(struct work_struct *work);
static DECLARE_DELAYED_WORK(tsc_irqwork, tsc_refine_calibration_work);
/**
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