[patch 08/38] x86/tsc: Use rdtsc() instead of get_cycles()
Thomas Gleixner <[email protected]> Fri, 10 Apr 2026 14:19:08 +0200
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| Message-ID | <[email protected]> |
This code knows that TSC is available so there is no point to use the TSC feature guarded get_cycles(). No functional change. Signed-off-by: Thomas Gleixner <[email protected]> --- arch/x86/kernel/tsc.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) --- a/arch/x86/kernel/tsc.c +++ b/arch/x86/kernel/tsc.c @@ -371,12 +371,12 @@ static u64 tsc_read_refs(u64 *p, int hpe int i; for (i = 0; i < MAX_RETRIES; i++) { - t1 = get_cycles(); + t1 = rdtsc(); if (hpet) *p = hpet_readl(HPET_COUNTER) & 0xFFFFFFFF; else *p = acpi_pm_read_early(); - t2 = get_cycles(); + t2 = rdtsc(); if ((t2 - t1) < thresh) return t2; } @@ -468,13 +468,13 @@ static unsigned long pit_calibrate_tsc(u outb(latch & 0xff, 0x42); outb(latch >> 8, 0x42); - tsc = t1 = t2 = get_cycles(); + tsc = t1 = t2 = rdtsc(); pitcnt = 0; tscmax = 0; tscmin = ULONG_MAX; while ((inb(0x61) & 0x20) == 0) { - t2 = get_cycles(); + t2 = rdtsc(); delta = t2 - tsc; tsc = t2; if ((unsigned long) delta < tscmin) @@ -553,9 +553,9 @@ static inline int pit_expect_msb(unsigne if (!pit_verify_msb(val)) break; prev_tsc = tsc; - tsc = get_cycles(); + tsc = rdtsc(); } - *deltap = get_cycles() - prev_tsc; + *deltap = rdtsc() - prev_tsc; *tscp = tsc; /*