diff options
Diffstat (limited to 'tools/perf/util/auxtrace.c')
-rw-r--r-- | tools/perf/util/auxtrace.c | 113 |
1 files changed, 113 insertions, 0 deletions
diff --git a/tools/perf/util/auxtrace.c b/tools/perf/util/auxtrace.c new file mode 100644 index 000000000000..dedb64613000 --- /dev/null +++ b/tools/perf/util/auxtrace.c @@ -0,0 +1,113 @@ +/* + * auxtrace.c: AUX area trace support + * Copyright (c) 2013-2015, Intel Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + */ + +#include <sys/types.h> +#include <sys/mman.h> +#include <stdbool.h> + +#include <linux/kernel.h> +#include <linux/perf_event.h> +#include <linux/types.h> +#include <linux/bitops.h> +#include <linux/log2.h> + +#include "../perf.h" +#include "util.h" +#include "evlist.h" +#include "cpumap.h" +#include "thread_map.h" +#include "asm/bug.h" +#include "auxtrace.h" + +int auxtrace_mmap__mmap(struct auxtrace_mmap *mm, + struct auxtrace_mmap_params *mp, + void *userpg, int fd) +{ + struct perf_event_mmap_page *pc = userpg; + +#if BITS_PER_LONG != 64 && !defined(HAVE_SYNC_COMPARE_AND_SWAP_SUPPORT) + pr_err("Cannot use AUX area tracing mmaps\n"); + return -1; +#endif + + WARN_ONCE(mm->base, "Uninitialized auxtrace_mmap\n"); + + mm->userpg = userpg; + mm->mask = mp->mask; + mm->len = mp->len; + mm->prev = 0; + mm->idx = mp->idx; + mm->tid = mp->tid; + mm->cpu = mp->cpu; + + if (!mp->len) { + mm->base = NULL; + return 0; + } + + pc->aux_offset = mp->offset; + pc->aux_size = mp->len; + + mm->base = mmap(NULL, mp->len, mp->prot, MAP_SHARED, fd, mp->offset); + if (mm->base == MAP_FAILED) { + pr_debug2("failed to mmap AUX area\n"); + mm->base = NULL; + return -1; + } + + return 0; +} + +void auxtrace_mmap__munmap(struct auxtrace_mmap *mm) +{ + if (mm->base) { + munmap(mm->base, mm->len); + mm->base = NULL; + } +} + +void auxtrace_mmap_params__init(struct auxtrace_mmap_params *mp, + off_t auxtrace_offset, + unsigned int auxtrace_pages, + bool auxtrace_overwrite) +{ + if (auxtrace_pages) { + mp->offset = auxtrace_offset; + mp->len = auxtrace_pages * (size_t)page_size; + mp->mask = is_power_of_2(mp->len) ? mp->len - 1 : 0; + mp->prot = PROT_READ | (auxtrace_overwrite ? 0 : PROT_WRITE); + pr_debug2("AUX area mmap length %zu\n", mp->len); + } else { + mp->len = 0; + } +} + +void auxtrace_mmap_params__set_idx(struct auxtrace_mmap_params *mp, + struct perf_evlist *evlist, int idx, + bool per_cpu) +{ + mp->idx = idx; + + if (per_cpu) { + mp->cpu = evlist->cpus->map[idx]; + if (evlist->threads) + mp->tid = evlist->threads->map[0]; + else + mp->tid = -1; + } else { + mp->cpu = -1; + mp->tid = evlist->threads->map[idx]; + } +} |