[PATCH v4 11/47] x86/tsc: Kill off x86_platform_ops.calibrate_{cpu,tsc}() hooks

[Sean Christopherson <seanjc@xxxxxxxxxx>]

Now that getting the CPU and/or TSC frequencies from the hypervisor uses
dedicated hooks, drop x86_platform_ops.calibrate_{cpu,tsc}() and instead
directly invoke the correct helper at each phase of (re)calibration.  In
addition to eliminating unnecessary code, this makes it a bit more obvious
when the "late" path invokes pit_hpet_ptimer_calibrate_cpu() instead of
x86_platform_ops.calibrate_cpu().

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
---
 arch/x86/include/asm/tsc.h      |  2 --
 arch/x86/include/asm/x86_init.h |  4 ----
 arch/x86/kernel/tsc.c           | 28 ++++++++++++----------------
 arch/x86/kernel/x86_init.c      |  2 --
 4 files changed, 12 insertions(+), 24 deletions(-)

diff --git a/arch/x86/include/asm/tsc.h b/arch/x86/include/asm/tsc.h
index 6cf26e62e9a6..4a224f99c3b9 100644
--- a/arch/x86/include/asm/tsc.h
+++ b/arch/x86/include/asm/tsc.h
@@ -97,8 +97,6 @@ extern void mark_tsc_unstable(char *reason);
 extern int unsynchronized_tsc(void);
 extern int check_tsc_unstable(void);
 extern void mark_tsc_async_resets(char *reason);
-extern unsigned long native_calibrate_cpu_early(void);
-extern unsigned long native_calibrate_tsc(void);
 extern unsigned long long native_sched_clock_from_tsc(u64 tsc);
 
 extern int tsc_clocksource_reliable;
diff --git a/arch/x86/include/asm/x86_init.h b/arch/x86/include/asm/x86_init.h
index a4f8a4aa601d..ada17827ea51 100644
--- a/arch/x86/include/asm/x86_init.h
+++ b/arch/x86/include/asm/x86_init.h
@@ -292,8 +292,6 @@ struct x86_hyper_runtime {
 
 /**
  * struct x86_platform_ops - platform specific runtime functions
- * @calibrate_cpu:             calibrate CPU
- * @calibrate_tsc:             calibrate TSC, if different from CPU
  * @get_wallclock:             get time from HW clock like RTC etc.
  * @set_wallclock:             set time back to HW clock
  * @iommu_shutdown:            set by an IOMMU driver for shutdown if necessary
@@ -317,8 +315,6 @@ struct x86_hyper_runtime {
  * @guest:                     guest incarnations callbacks
  */
 struct x86_platform_ops {
-       unsigned long (*calibrate_cpu)(void);
-       unsigned long (*calibrate_tsc)(void);
        void (*get_wallclock)(struct timespec64 *ts);
        int (*set_wallclock)(const struct timespec64 *ts);
        void (*iommu_shutdown)(void);
diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c
index 8cef918486db..5b4b6e43c94c 100644
--- a/arch/x86/kernel/tsc.c
+++ b/arch/x86/kernel/tsc.c
@@ -696,7 +696,7 @@ int __init cpuid_get_tsc_freq(struct cpuid_tsc_info *info)
  * native_calibrate_tsc - determine TSC frequency
  * Determine TSC frequency via CPUID, else return 0.
  */
-unsigned long native_calibrate_tsc(void)
+static unsigned long native_calibrate_tsc(void)
 {
        struct cpuid_tsc_info info;
 
@@ -931,7 +931,7 @@ static unsigned long pit_hpet_ptimer_calibrate_cpu(void)
 /**
  * native_calibrate_cpu_early - can calibrate the cpu early in boot
  */
-unsigned long native_calibrate_cpu_early(void)
+static unsigned long native_calibrate_cpu_early(void)
 {
        unsigned long flags, fast_calibrate = cpu_khz_from_cpuid();
 
@@ -945,7 +945,7 @@ unsigned long native_calibrate_cpu_early(void)
        return fast_calibrate;
 }
 
-
+#ifndef CONFIG_SMP
 /**
  * native_calibrate_cpu - calibrate the cpu
  */
@@ -958,6 +958,7 @@ static unsigned long native_calibrate_cpu(void)
 
        return tsc_freq;
 }
+#endif
 
 void recalibrate_cpu_khz(void)
 {
@@ -967,9 +968,9 @@ void recalibrate_cpu_khz(void)
        if (!boot_cpu_has(X86_FEATURE_TSC))
                return;
 
-       cpu_khz = x86_platform.calibrate_cpu();
+       cpu_khz = native_calibrate_cpu();
        if (!boot_cpu_has(X86_FEATURE_TSC_KNOWN_FREQ))
-               tsc_khz = x86_platform.calibrate_tsc();
+               tsc_khz = native_calibrate_tsc();
        if (tsc_khz == 0)
                tsc_khz = cpu_khz;
        else if (abs(cpu_khz - tsc_khz) * 10 > tsc_khz)
@@ -1483,17 +1484,19 @@ static bool __init determine_cpu_tsc_frequencies(bool 
early,
        WARN_ON(cpu_khz || tsc_khz);
 
        if (early) {
+               /*
+                * Early CPU calibration can only use methods that are available
+                * early in boot (obviously).
+                */
                if (known_cpu_khz)
                        cpu_khz = known_cpu_khz;
                else
-                       cpu_khz = x86_platform.calibrate_cpu();
+                       cpu_khz = native_calibrate_cpu_early();
                if (known_tsc_khz)
                        tsc_khz = known_tsc_khz;
                else
-                       tsc_khz = x86_platform.calibrate_tsc();
+                       tsc_khz = native_calibrate_tsc();
        } else {
-               /* We should not be here with non-native cpu calibration */
-               WARN_ON(x86_platform.calibrate_cpu != native_calibrate_cpu);
                cpu_khz = pit_hpet_ptimer_calibrate_cpu();
        }
 
@@ -1590,13 +1593,6 @@ void __init tsc_init(void)
                return;
        }
 
-       /*
-        * native_calibrate_cpu_early can only calibrate using methods that are
-        * available early in boot.
-        */
-       if (x86_platform.calibrate_cpu == native_calibrate_cpu_early)
-               x86_platform.calibrate_cpu = native_calibrate_cpu;
-
        if (!tsc_khz) {
                /* We failed to determine frequencies earlier, try again */
                if (!determine_cpu_tsc_frequencies(false, 0, 0)) {
diff --git a/arch/x86/kernel/x86_init.c b/arch/x86/kernel/x86_init.c
index ebefb77c37bb..c674cbbd466d 100644
--- a/arch/x86/kernel/x86_init.c
+++ b/arch/x86/kernel/x86_init.c
@@ -144,8 +144,6 @@ static void enc_kexec_finish_noop(void) {}
 static bool is_private_mmio_noop(u64 addr) {return false; }
 
 struct x86_platform_ops x86_platform __ro_after_init = {
-       .calibrate_cpu                  = native_calibrate_cpu_early,
-       .calibrate_tsc                  = native_calibrate_tsc,
        .get_wallclock                  = mach_get_cmos_time,
        .set_wallclock                  = mach_set_cmos_time,
        .iommu_shutdown                 = iommu_shutdown_noop,
-- 
2.54.0.823.g6e5bcc1fc9-goog