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Diffstat (limited to 'arch/x86/vdso/vclock_gettime.c')
-rw-r--r--arch/x86/vdso/vclock_gettime.c351
1 files changed, 0 insertions, 351 deletions
diff --git a/arch/x86/vdso/vclock_gettime.c b/arch/x86/vdso/vclock_gettime.c
deleted file mode 100644
index 979332275..000000000
--- a/arch/x86/vdso/vclock_gettime.c
+++ /dev/null
@@ -1,351 +0,0 @@
-/*
- * Copyright 2006 Andi Kleen, SUSE Labs.
- * Subject to the GNU Public License, v.2
- *
- * Fast user context implementation of clock_gettime, gettimeofday, and time.
- *
- * 32 Bit compat layer by Stefani Seibold <stefani@seibold.net>
- * sponsored by Rohde & Schwarz GmbH & Co. KG Munich/Germany
- *
- * The code should have no internal unresolved relocations.
- * Check with readelf after changing.
- */
-
-#include <uapi/linux/time.h>
-#include <asm/vgtod.h>
-#include <asm/hpet.h>
-#include <asm/vvar.h>
-#include <asm/unistd.h>
-#include <asm/msr.h>
-#include <linux/math64.h>
-#include <linux/time.h>
-
-#define gtod (&VVAR(vsyscall_gtod_data))
-
-extern int __vdso_clock_gettime(clockid_t clock, struct timespec *ts);
-extern int __vdso_gettimeofday(struct timeval *tv, struct timezone *tz);
-extern time_t __vdso_time(time_t *t);
-
-#ifdef CONFIG_HPET_TIMER
-extern u8 hpet_page
- __attribute__((visibility("hidden")));
-
-static notrace cycle_t vread_hpet(void)
-{
- return *(const volatile u32 *)(&hpet_page + HPET_COUNTER);
-}
-#endif
-
-#ifndef BUILD_VDSO32
-
-#include <linux/kernel.h>
-#include <asm/vsyscall.h>
-#include <asm/fixmap.h>
-#include <asm/pvclock.h>
-
-notrace static long vdso_fallback_gettime(long clock, struct timespec *ts)
-{
- long ret;
- asm("syscall" : "=a" (ret) :
- "0" (__NR_clock_gettime), "D" (clock), "S" (ts) : "memory");
- return ret;
-}
-
-notrace static long vdso_fallback_gtod(struct timeval *tv, struct timezone *tz)
-{
- long ret;
-
- asm("syscall" : "=a" (ret) :
- "0" (__NR_gettimeofday), "D" (tv), "S" (tz) : "memory");
- return ret;
-}
-
-#ifdef CONFIG_PARAVIRT_CLOCK
-
-static notrace const struct pvclock_vsyscall_time_info *get_pvti(int cpu)
-{
- const struct pvclock_vsyscall_time_info *pvti_base;
- int idx = cpu / (PAGE_SIZE/PVTI_SIZE);
- int offset = cpu % (PAGE_SIZE/PVTI_SIZE);
-
- BUG_ON(PVCLOCK_FIXMAP_BEGIN + idx > PVCLOCK_FIXMAP_END);
-
- pvti_base = (struct pvclock_vsyscall_time_info *)
- __fix_to_virt(PVCLOCK_FIXMAP_BEGIN+idx);
-
- return &pvti_base[offset];
-}
-
-static notrace cycle_t vread_pvclock(int *mode)
-{
- const struct pvclock_vsyscall_time_info *pvti;
- cycle_t ret;
- u64 last;
- u32 version;
- u8 flags;
- unsigned cpu, cpu1;
-
-
- /*
- * Note: hypervisor must guarantee that:
- * 1. cpu ID number maps 1:1 to per-CPU pvclock time info.
- * 2. that per-CPU pvclock time info is updated if the
- * underlying CPU changes.
- * 3. that version is increased whenever underlying CPU
- * changes.
- *
- */
- do {
- cpu = __getcpu() & VGETCPU_CPU_MASK;
- /* TODO: We can put vcpu id into higher bits of pvti.version.
- * This will save a couple of cycles by getting rid of
- * __getcpu() calls (Gleb).
- */
-
- pvti = get_pvti(cpu);
-
- version = __pvclock_read_cycles(&pvti->pvti, &ret, &flags);
-
- /*
- * Test we're still on the cpu as well as the version.
- * We could have been migrated just after the first
- * vgetcpu but before fetching the version, so we
- * wouldn't notice a version change.
- */
- cpu1 = __getcpu() & VGETCPU_CPU_MASK;
- } while (unlikely(cpu != cpu1 ||
- (pvti->pvti.version & 1) ||
- pvti->pvti.version != version));
-
- if (unlikely(!(flags & PVCLOCK_TSC_STABLE_BIT)))
- *mode = VCLOCK_NONE;
-
- /* refer to tsc.c read_tsc() comment for rationale */
- last = gtod->cycle_last;
-
- if (likely(ret >= last))
- return ret;
-
- return last;
-}
-#endif
-
-#else
-
-notrace static long vdso_fallback_gettime(long clock, struct timespec *ts)
-{
- long ret;
-
- asm(
- "mov %%ebx, %%edx \n"
- "mov %2, %%ebx \n"
- "call __kernel_vsyscall \n"
- "mov %%edx, %%ebx \n"
- : "=a" (ret)
- : "0" (__NR_clock_gettime), "g" (clock), "c" (ts)
- : "memory", "edx");
- return ret;
-}
-
-notrace static long vdso_fallback_gtod(struct timeval *tv, struct timezone *tz)
-{
- long ret;
-
- asm(
- "mov %%ebx, %%edx \n"
- "mov %2, %%ebx \n"
- "call __kernel_vsyscall \n"
- "mov %%edx, %%ebx \n"
- : "=a" (ret)
- : "0" (__NR_gettimeofday), "g" (tv), "c" (tz)
- : "memory", "edx");
- return ret;
-}
-
-#ifdef CONFIG_PARAVIRT_CLOCK
-
-static notrace cycle_t vread_pvclock(int *mode)
-{
- *mode = VCLOCK_NONE;
- return 0;
-}
-#endif
-
-#endif
-
-notrace static cycle_t vread_tsc(void)
-{
- cycle_t ret;
- u64 last;
-
- /*
- * Empirically, a fence (of type that depends on the CPU)
- * before rdtsc is enough to ensure that rdtsc is ordered
- * with respect to loads. The various CPU manuals are unclear
- * as to whether rdtsc can be reordered with later loads,
- * but no one has ever seen it happen.
- */
- rdtsc_barrier();
- ret = (cycle_t)__native_read_tsc();
-
- last = gtod->cycle_last;
-
- if (likely(ret >= last))
- return ret;
-
- /*
- * GCC likes to generate cmov here, but this branch is extremely
- * predictable (it's just a funciton of time and the likely is
- * very likely) and there's a data dependence, so force GCC
- * to generate a branch instead. I don't barrier() because
- * we don't actually need a barrier, and if this function
- * ever gets inlined it will generate worse code.
- */
- asm volatile ("");
- return last;
-}
-
-notrace static inline u64 vgetsns(int *mode)
-{
- u64 v;
- cycles_t cycles;
-
- if (gtod->vclock_mode == VCLOCK_TSC)
- cycles = vread_tsc();
-#ifdef CONFIG_HPET_TIMER
- else if (gtod->vclock_mode == VCLOCK_HPET)
- cycles = vread_hpet();
-#endif
-#ifdef CONFIG_PARAVIRT_CLOCK
- else if (gtod->vclock_mode == VCLOCK_PVCLOCK)
- cycles = vread_pvclock(mode);
-#endif
- else
- return 0;
- v = (cycles - gtod->cycle_last) & gtod->mask;
- return v * gtod->mult;
-}
-
-/* Code size doesn't matter (vdso is 4k anyway) and this is faster. */
-notrace static int __always_inline do_realtime(struct timespec *ts)
-{
- unsigned long seq;
- u64 ns;
- int mode;
-
- do {
- seq = gtod_read_begin(gtod);
- mode = gtod->vclock_mode;
- ts->tv_sec = gtod->wall_time_sec;
- ns = gtod->wall_time_snsec;
- ns += vgetsns(&mode);
- ns >>= gtod->shift;
- } while (unlikely(gtod_read_retry(gtod, seq)));
-
- ts->tv_sec += __iter_div_u64_rem(ns, NSEC_PER_SEC, &ns);
- ts->tv_nsec = ns;
-
- return mode;
-}
-
-notrace static int __always_inline do_monotonic(struct timespec *ts)
-{
- unsigned long seq;
- u64 ns;
- int mode;
-
- do {
- seq = gtod_read_begin(gtod);
- mode = gtod->vclock_mode;
- ts->tv_sec = gtod->monotonic_time_sec;
- ns = gtod->monotonic_time_snsec;
- ns += vgetsns(&mode);
- ns >>= gtod->shift;
- } while (unlikely(gtod_read_retry(gtod, seq)));
-
- ts->tv_sec += __iter_div_u64_rem(ns, NSEC_PER_SEC, &ns);
- ts->tv_nsec = ns;
-
- return mode;
-}
-
-notrace static void do_realtime_coarse(struct timespec *ts)
-{
- unsigned long seq;
- do {
- seq = gtod_read_begin(gtod);
- ts->tv_sec = gtod->wall_time_coarse_sec;
- ts->tv_nsec = gtod->wall_time_coarse_nsec;
- } while (unlikely(gtod_read_retry(gtod, seq)));
-}
-
-notrace static void do_monotonic_coarse(struct timespec *ts)
-{
- unsigned long seq;
- do {
- seq = gtod_read_begin(gtod);
- ts->tv_sec = gtod->monotonic_time_coarse_sec;
- ts->tv_nsec = gtod->monotonic_time_coarse_nsec;
- } while (unlikely(gtod_read_retry(gtod, seq)));
-}
-
-notrace int __vdso_clock_gettime(clockid_t clock, struct timespec *ts)
-{
- switch (clock) {
- case CLOCK_REALTIME:
- if (do_realtime(ts) == VCLOCK_NONE)
- goto fallback;
- break;
- case CLOCK_MONOTONIC:
- if (do_monotonic(ts) == VCLOCK_NONE)
- goto fallback;
- break;
- case CLOCK_REALTIME_COARSE:
- do_realtime_coarse(ts);
- break;
- case CLOCK_MONOTONIC_COARSE:
- do_monotonic_coarse(ts);
- break;
- default:
- goto fallback;
- }
-
- return 0;
-fallback:
- return vdso_fallback_gettime(clock, ts);
-}
-int clock_gettime(clockid_t, struct timespec *)
- __attribute__((weak, alias("__vdso_clock_gettime")));
-
-notrace int __vdso_gettimeofday(struct timeval *tv, struct timezone *tz)
-{
- if (likely(tv != NULL)) {
- if (unlikely(do_realtime((struct timespec *)tv) == VCLOCK_NONE))
- return vdso_fallback_gtod(tv, tz);
- tv->tv_usec /= 1000;
- }
- if (unlikely(tz != NULL)) {
- tz->tz_minuteswest = gtod->tz_minuteswest;
- tz->tz_dsttime = gtod->tz_dsttime;
- }
-
- return 0;
-}
-int gettimeofday(struct timeval *, struct timezone *)
- __attribute__((weak, alias("__vdso_gettimeofday")));
-
-/*
- * This will break when the xtime seconds get inaccurate, but that is
- * unlikely
- */
-notrace time_t __vdso_time(time_t *t)
-{
- /* This is atomic on x86 so we don't need any locks. */
- time_t result = ACCESS_ONCE(gtod->wall_time_sec);
-
- if (t)
- *t = result;
- return result;
-}
-int time(time_t *t)
- __attribute__((weak, alias("__vdso_time")));