diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
commit | 5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch) | |
tree | a94efe259b9009378be6d90eb30d2b019d95c194 /tools/perf/util/tsc.c | |
parent | Initial commit. (diff) | |
download | linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.tar.xz linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.zip |
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'tools/perf/util/tsc.c')
-rw-r--r-- | tools/perf/util/tsc.c | 112 |
1 files changed, 112 insertions, 0 deletions
diff --git a/tools/perf/util/tsc.c b/tools/perf/util/tsc.c new file mode 100644 index 000000000..62b4c75c9 --- /dev/null +++ b/tools/perf/util/tsc.c @@ -0,0 +1,112 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <errno.h> + +#include <linux/compiler.h> +#include <linux/perf_event.h> +#include <linux/stddef.h> +#include <linux/types.h> + +#include <asm/barrier.h> + +#include "event.h" +#include "synthetic-events.h" +#include "debug.h" +#include "tsc.h" + +u64 perf_time_to_tsc(u64 ns, struct perf_tsc_conversion *tc) +{ + u64 t, quot, rem; + + t = ns - tc->time_zero; + quot = t / tc->time_mult; + rem = t % tc->time_mult; + return (quot << tc->time_shift) + + (rem << tc->time_shift) / tc->time_mult; +} + +u64 tsc_to_perf_time(u64 cyc, struct perf_tsc_conversion *tc) +{ + u64 quot, rem; + + if (tc->cap_user_time_short) + cyc = tc->time_cycles + + ((cyc - tc->time_cycles) & tc->time_mask); + + quot = cyc >> tc->time_shift; + rem = cyc & (((u64)1 << tc->time_shift) - 1); + return tc->time_zero + quot * tc->time_mult + + ((rem * tc->time_mult) >> tc->time_shift); +} + +int perf_read_tsc_conversion(const struct perf_event_mmap_page *pc, + struct perf_tsc_conversion *tc) +{ + u32 seq; + int i = 0; + + while (1) { + seq = pc->lock; + rmb(); + tc->time_mult = pc->time_mult; + tc->time_shift = pc->time_shift; + tc->time_zero = pc->time_zero; + tc->time_cycles = pc->time_cycles; + tc->time_mask = pc->time_mask; + tc->cap_user_time_zero = pc->cap_user_time_zero; + tc->cap_user_time_short = pc->cap_user_time_short; + rmb(); + if (pc->lock == seq && !(seq & 1)) + break; + if (++i > 10000) { + pr_debug("failed to get perf_event_mmap_page lock\n"); + return -EINVAL; + } + } + + if (!tc->cap_user_time_zero) + return -EOPNOTSUPP; + + return 0; +} + +int perf_event__synth_time_conv(const struct perf_event_mmap_page *pc, + struct perf_tool *tool, + perf_event__handler_t process, + struct machine *machine) +{ + union perf_event event = { + .time_conv = { + .header = { + .type = PERF_RECORD_TIME_CONV, + .size = sizeof(struct perf_record_time_conv), + }, + }, + }; + struct perf_tsc_conversion tc; + int err; + + if (!pc) + return 0; + err = perf_read_tsc_conversion(pc, &tc); + if (err == -EOPNOTSUPP) + return 0; + if (err) + return err; + + pr_debug2("Synthesizing TSC conversion information\n"); + + event.time_conv.time_mult = tc.time_mult; + event.time_conv.time_shift = tc.time_shift; + event.time_conv.time_zero = tc.time_zero; + event.time_conv.time_cycles = tc.time_cycles; + event.time_conv.time_mask = tc.time_mask; + event.time_conv.cap_user_time_zero = tc.cap_user_time_zero; + event.time_conv.cap_user_time_short = tc.cap_user_time_short; + + return process(tool, &event, NULL, machine); +} + +u64 __weak rdtsc(void) +{ + return 0; +} |