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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
commit | ace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch) | |
tree | b2d64bc10158fdd5497876388cd68142ca374ed3 /arch/sparc/vdso/vclock_gettime.c | |
parent | Initial commit. (diff) | |
download | linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip |
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | arch/sparc/vdso/vclock_gettime.c | 373 |
1 files changed, 373 insertions, 0 deletions
diff --git a/arch/sparc/vdso/vclock_gettime.c b/arch/sparc/vdso/vclock_gettime.c new file mode 100644 index 0000000000..e794edde67 --- /dev/null +++ b/arch/sparc/vdso/vclock_gettime.c @@ -0,0 +1,373 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright 2006 Andi Kleen, SUSE Labs. + * + * Fast user context implementation of clock_gettime, gettimeofday, and time. + * + * The code should have no internal unresolved relocations. + * Check with readelf after changing. + * Also alternative() doesn't work. + */ +/* + * Copyright (c) 2017 Oracle and/or its affiliates. All rights reserved. + */ + +#include <linux/kernel.h> +#include <linux/time.h> +#include <linux/string.h> +#include <asm/io.h> +#include <asm/unistd.h> +#include <asm/timex.h> +#include <asm/clocksource.h> +#include <asm/vvar.h> + +#ifdef CONFIG_SPARC64 +#define SYSCALL_STRING \ + "ta 0x6d;" \ + "bcs,a 1f;" \ + " sub %%g0, %%o0, %%o0;" \ + "1:" +#else +#define SYSCALL_STRING \ + "ta 0x10;" \ + "bcs,a 1f;" \ + " sub %%g0, %%o0, %%o0;" \ + "1:" +#endif + +#define SYSCALL_CLOBBERS \ + "f0", "f1", "f2", "f3", "f4", "f5", "f6", "f7", \ + "f8", "f9", "f10", "f11", "f12", "f13", "f14", "f15", \ + "f16", "f17", "f18", "f19", "f20", "f21", "f22", "f23", \ + "f24", "f25", "f26", "f27", "f28", "f29", "f30", "f31", \ + "f32", "f34", "f36", "f38", "f40", "f42", "f44", "f46", \ + "f48", "f50", "f52", "f54", "f56", "f58", "f60", "f62", \ + "cc", "memory" + +/* + * Compute the vvar page's address in the process address space, and return it + * as a pointer to the vvar_data. + */ +notrace static __always_inline struct vvar_data *get_vvar_data(void) +{ + unsigned long ret; + + /* + * vdso data page is the first vDSO page so grab the PC + * and move up a page to get to the data page. + */ + __asm__("rd %%pc, %0" : "=r" (ret)); + ret &= ~(8192 - 1); + ret -= 8192; + + return (struct vvar_data *) ret; +} + +notrace static long vdso_fallback_gettime(long clock, struct __kernel_old_timespec *ts) +{ + register long num __asm__("g1") = __NR_clock_gettime; + register long o0 __asm__("o0") = clock; + register long o1 __asm__("o1") = (long) ts; + + __asm__ __volatile__(SYSCALL_STRING : "=r" (o0) : "r" (num), + "0" (o0), "r" (o1) : SYSCALL_CLOBBERS); + return o0; +} + +notrace static long vdso_fallback_gettimeofday(struct __kernel_old_timeval *tv, struct timezone *tz) +{ + register long num __asm__("g1") = __NR_gettimeofday; + register long o0 __asm__("o0") = (long) tv; + register long o1 __asm__("o1") = (long) tz; + + __asm__ __volatile__(SYSCALL_STRING : "=r" (o0) : "r" (num), + "0" (o0), "r" (o1) : SYSCALL_CLOBBERS); + return o0; +} + +#ifdef CONFIG_SPARC64 +notrace static __always_inline u64 vread_tick(void) +{ + u64 ret; + + __asm__ __volatile__("rd %%tick, %0" : "=r" (ret)); + return ret; +} + +notrace static __always_inline u64 vread_tick_stick(void) +{ + u64 ret; + + __asm__ __volatile__("rd %%asr24, %0" : "=r" (ret)); + return ret; +} +#else +notrace static __always_inline u64 vread_tick(void) +{ + register unsigned long long ret asm("o4"); + + __asm__ __volatile__("rd %%tick, %L0\n\t" + "srlx %L0, 32, %H0" + : "=r" (ret)); + return ret; +} + +notrace static __always_inline u64 vread_tick_stick(void) +{ + register unsigned long long ret asm("o4"); + + __asm__ __volatile__("rd %%asr24, %L0\n\t" + "srlx %L0, 32, %H0" + : "=r" (ret)); + return ret; +} +#endif + +notrace static __always_inline u64 vgetsns(struct vvar_data *vvar) +{ + u64 v; + u64 cycles; + + cycles = vread_tick(); + v = (cycles - vvar->clock.cycle_last) & vvar->clock.mask; + return v * vvar->clock.mult; +} + +notrace static __always_inline u64 vgetsns_stick(struct vvar_data *vvar) +{ + u64 v; + u64 cycles; + + cycles = vread_tick_stick(); + v = (cycles - vvar->clock.cycle_last) & vvar->clock.mask; + return v * vvar->clock.mult; +} + +notrace static __always_inline int do_realtime(struct vvar_data *vvar, + struct __kernel_old_timespec *ts) +{ + unsigned long seq; + u64 ns; + + do { + seq = vvar_read_begin(vvar); + ts->tv_sec = vvar->wall_time_sec; + ns = vvar->wall_time_snsec; + ns += vgetsns(vvar); + ns >>= vvar->clock.shift; + } while (unlikely(vvar_read_retry(vvar, seq))); + + ts->tv_sec += __iter_div_u64_rem(ns, NSEC_PER_SEC, &ns); + ts->tv_nsec = ns; + + return 0; +} + +notrace static __always_inline int do_realtime_stick(struct vvar_data *vvar, + struct __kernel_old_timespec *ts) +{ + unsigned long seq; + u64 ns; + + do { + seq = vvar_read_begin(vvar); + ts->tv_sec = vvar->wall_time_sec; + ns = vvar->wall_time_snsec; + ns += vgetsns_stick(vvar); + ns >>= vvar->clock.shift; + } while (unlikely(vvar_read_retry(vvar, seq))); + + ts->tv_sec += __iter_div_u64_rem(ns, NSEC_PER_SEC, &ns); + ts->tv_nsec = ns; + + return 0; +} + +notrace static __always_inline int do_monotonic(struct vvar_data *vvar, + struct __kernel_old_timespec *ts) +{ + unsigned long seq; + u64 ns; + + do { + seq = vvar_read_begin(vvar); + ts->tv_sec = vvar->monotonic_time_sec; + ns = vvar->monotonic_time_snsec; + ns += vgetsns(vvar); + ns >>= vvar->clock.shift; + } while (unlikely(vvar_read_retry(vvar, seq))); + + ts->tv_sec += __iter_div_u64_rem(ns, NSEC_PER_SEC, &ns); + ts->tv_nsec = ns; + + return 0; +} + +notrace static __always_inline int do_monotonic_stick(struct vvar_data *vvar, + struct __kernel_old_timespec *ts) +{ + unsigned long seq; + u64 ns; + + do { + seq = vvar_read_begin(vvar); + ts->tv_sec = vvar->monotonic_time_sec; + ns = vvar->monotonic_time_snsec; + ns += vgetsns_stick(vvar); + ns >>= vvar->clock.shift; + } while (unlikely(vvar_read_retry(vvar, seq))); + + ts->tv_sec += __iter_div_u64_rem(ns, NSEC_PER_SEC, &ns); + ts->tv_nsec = ns; + + return 0; +} + +notrace static int do_realtime_coarse(struct vvar_data *vvar, + struct __kernel_old_timespec *ts) +{ + unsigned long seq; + + do { + seq = vvar_read_begin(vvar); + ts->tv_sec = vvar->wall_time_coarse_sec; + ts->tv_nsec = vvar->wall_time_coarse_nsec; + } while (unlikely(vvar_read_retry(vvar, seq))); + return 0; +} + +notrace static int do_monotonic_coarse(struct vvar_data *vvar, + struct __kernel_old_timespec *ts) +{ + unsigned long seq; + + do { + seq = vvar_read_begin(vvar); + ts->tv_sec = vvar->monotonic_time_coarse_sec; + ts->tv_nsec = vvar->monotonic_time_coarse_nsec; + } while (unlikely(vvar_read_retry(vvar, seq))); + + return 0; +} + +notrace int +__vdso_clock_gettime(clockid_t clock, struct __kernel_old_timespec *ts) +{ + struct vvar_data *vvd = get_vvar_data(); + + switch (clock) { + case CLOCK_REALTIME: + if (unlikely(vvd->vclock_mode == VCLOCK_NONE)) + break; + return do_realtime(vvd, ts); + case CLOCK_MONOTONIC: + if (unlikely(vvd->vclock_mode == VCLOCK_NONE)) + break; + return do_monotonic(vvd, ts); + case CLOCK_REALTIME_COARSE: + return do_realtime_coarse(vvd, ts); + case CLOCK_MONOTONIC_COARSE: + return do_monotonic_coarse(vvd, ts); + } + /* + * Unknown clock ID ? Fall back to the syscall. + */ + return vdso_fallback_gettime(clock, ts); +} +int +clock_gettime(clockid_t, struct __kernel_old_timespec *) + __attribute__((weak, alias("__vdso_clock_gettime"))); + +notrace int +__vdso_clock_gettime_stick(clockid_t clock, struct __kernel_old_timespec *ts) +{ + struct vvar_data *vvd = get_vvar_data(); + + switch (clock) { + case CLOCK_REALTIME: + if (unlikely(vvd->vclock_mode == VCLOCK_NONE)) + break; + return do_realtime_stick(vvd, ts); + case CLOCK_MONOTONIC: + if (unlikely(vvd->vclock_mode == VCLOCK_NONE)) + break; + return do_monotonic_stick(vvd, ts); + case CLOCK_REALTIME_COARSE: + return do_realtime_coarse(vvd, ts); + case CLOCK_MONOTONIC_COARSE: + return do_monotonic_coarse(vvd, ts); + } + /* + * Unknown clock ID ? Fall back to the syscall. + */ + return vdso_fallback_gettime(clock, ts); +} + +notrace int +__vdso_gettimeofday(struct __kernel_old_timeval *tv, struct timezone *tz) +{ + struct vvar_data *vvd = get_vvar_data(); + + if (likely(vvd->vclock_mode != VCLOCK_NONE)) { + if (likely(tv != NULL)) { + union tstv_t { + struct __kernel_old_timespec ts; + struct __kernel_old_timeval tv; + } *tstv = (union tstv_t *) tv; + do_realtime(vvd, &tstv->ts); + /* + * Assign before dividing to ensure that the division is + * done in the type of tv_usec, not tv_nsec. + * + * There cannot be > 1 billion usec in a second: + * do_realtime() has already distributed such overflow + * into tv_sec. So we can assign it to an int safely. + */ + tstv->tv.tv_usec = tstv->ts.tv_nsec; + tstv->tv.tv_usec /= 1000; + } + if (unlikely(tz != NULL)) { + /* Avoid memcpy. Some old compilers fail to inline it */ + tz->tz_minuteswest = vvd->tz_minuteswest; + tz->tz_dsttime = vvd->tz_dsttime; + } + return 0; + } + return vdso_fallback_gettimeofday(tv, tz); +} +int +gettimeofday(struct __kernel_old_timeval *, struct timezone *) + __attribute__((weak, alias("__vdso_gettimeofday"))); + +notrace int +__vdso_gettimeofday_stick(struct __kernel_old_timeval *tv, struct timezone *tz) +{ + struct vvar_data *vvd = get_vvar_data(); + + if (likely(vvd->vclock_mode != VCLOCK_NONE)) { + if (likely(tv != NULL)) { + union tstv_t { + struct __kernel_old_timespec ts; + struct __kernel_old_timeval tv; + } *tstv = (union tstv_t *) tv; + do_realtime_stick(vvd, &tstv->ts); + /* + * Assign before dividing to ensure that the division is + * done in the type of tv_usec, not tv_nsec. + * + * There cannot be > 1 billion usec in a second: + * do_realtime() has already distributed such overflow + * into tv_sec. So we can assign it to an int safely. + */ + tstv->tv.tv_usec = tstv->ts.tv_nsec; + tstv->tv.tv_usec /= 1000; + } + if (unlikely(tz != NULL)) { + /* Avoid memcpy. Some old compilers fail to inline it */ + tz->tz_minuteswest = vvd->tz_minuteswest; + tz->tz_dsttime = vvd->tz_dsttime; + } + return 0; + } + return vdso_fallback_gettimeofday(tv, tz); +} |