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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /tools/perf/util/tsc.c | |
parent | Initial commit. (diff) | |
download | linux-upstream.tar.xz linux-upstream.zip |
Adding upstream version 6.1.76.upstream/6.1.76upstream
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 | 142 |
1 files changed, 142 insertions, 0 deletions
diff --git a/tools/perf/util/tsc.c b/tools/perf/util/tsc.c new file mode 100644 index 000000000..f19791d46 --- /dev/null +++ b/tools/perf/util/tsc.c @@ -0,0 +1,142 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <errno.h> +#include <inttypes.h> +#include <string.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; +} + +size_t perf_event__fprintf_time_conv(union perf_event *event, FILE *fp) +{ + struct perf_record_time_conv *tc = (struct perf_record_time_conv *)event; + size_t ret; + + ret = fprintf(fp, "\n... Time Shift %" PRI_lu64 "\n", tc->time_shift); + ret += fprintf(fp, "... Time Muliplier %" PRI_lu64 "\n", tc->time_mult); + ret += fprintf(fp, "... Time Zero %" PRI_lu64 "\n", tc->time_zero); + + /* + * The event TIME_CONV was extended for the fields from "time_cycles" + * when supported cap_user_time_short, for backward compatibility, + * prints the extended fields only if they are contained in the event. + */ + if (event_contains(*tc, time_cycles)) { + ret += fprintf(fp, "... Time Cycles %" PRI_lu64 "\n", + tc->time_cycles); + ret += fprintf(fp, "... Time Mask %#" PRI_lx64 "\n", + tc->time_mask); + ret += fprintf(fp, "... Cap Time Zero %" PRId32 "\n", + tc->cap_user_time_zero); + ret += fprintf(fp, "... Cap Time Short %" PRId32 "\n", + tc->cap_user_time_short); + } + + return ret; +} |