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Diffstat (limited to '')
| -rw-r--r-- | src/perf/perf.cpp | 266 |
1 files changed, 266 insertions, 0 deletions
diff --git a/src/perf/perf.cpp b/src/perf/perf.cpp new file mode 100644 index 0000000..9ed0ba8 --- /dev/null +++ b/src/perf/perf.cpp @@ -0,0 +1,266 @@ +/* + * Copyright 2010, Intel Corporation + * + * This file is part of PowerTOP + * + * This program file is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; version 2 of the License. + * + * This program is distributed in the hope that 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. + * + * You should have received a copy of the GNU General Public License + * along with this program in a file named COPYING; if not, write to the + * Free Software Foundation, Inc, + * 51 Franklin Street, Fifth Floor, + * Boston, MA 02110-1301 USA + * or just google for it. + * + * Authors: + * Arjan van de Ven <arjan@linux.intel.com> + */ + +#include <iostream> +#include <fstream> + +#include <errno.h> +#include <unistd.h> +#include <stdio.h> +#include <stdlib.h> +#include <errno.h> +#include <string.h> +#include <sys/mman.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <sys/ioctl.h> + +#include <fcntl.h> + +#include "perf_event.h" +#include "perf.h" +#include "../lib.h" +#include "../display.h" + +struct pevent *perf_event::pevent; + +static int get_trace_type(const char *eventname) +{ + string str; + int this_trace; + + str = read_sysfs_string("/sys/kernel/debug/tracing/events/%s/id", + eventname); + if (str.length() < 1) + return -1; + + this_trace = strtoull(str.c_str(), NULL, 10); + return this_trace; +} + +static inline int sys_perf_event_open(struct perf_event_attr *attr, + pid_t pid, int cpu, int group_fd, + unsigned long flags) +{ + attr->size = sizeof(*attr); + return syscall(__NR_perf_event_open, attr, pid, cpu, + group_fd, flags); +} + +void perf_event::create_perf_event(char *eventname, int _cpu) +{ + struct perf_event_attr attr; + int ret; + int err; + + struct { + __u64 count; + __u64 time_enabled; + __u64 time_running; + __u64 id; + } read_data; + + if (perf_fd != -1) + clear(); + + memset(&attr, 0, sizeof(attr)); + + attr.read_format = PERF_FORMAT_TOTAL_TIME_ENABLED | + PERF_FORMAT_TOTAL_TIME_RUNNING | + PERF_FORMAT_ID; + + attr.sample_freq = 0; + attr.sample_period = 1; + attr.sample_type |= PERF_SAMPLE_RAW | PERF_SAMPLE_CPU | PERF_SAMPLE_TIME; + + attr.mmap = 1; + attr.comm = 1; + attr.inherit = 0; + attr.disabled = 1; + + attr.type = PERF_TYPE_TRACEPOINT; + attr.config = trace_type; + + if (attr.config <= 0) + return; + + perf_fd = sys_perf_event_open(&attr, -1, _cpu, -1, 0); + + if (perf_fd < 0) { + err = errno; + reset_display(); + if (err == EMFILE) + fprintf(stderr, _("Too many open files, please increase the limit of open file descriptors.\n")); + else { + fprintf(stderr, _("PowerTOP %s needs the kernel to support the 'perf' subsystem\n"), PACKAGE_VERSION); + fprintf(stderr, _("as well as support for trace points in the kernel:\n")); + fprintf(stderr, "CONFIG_PERF_EVENTS=y\nCONFIG_PERF_COUNTERS=y\nCONFIG_TRACEPOINTS=y\nCONFIG_TRACING=y\n"); + } + exit(EXIT_FAILURE); + } + if (read(perf_fd, &read_data, sizeof(read_data)) == -1) { + reset_display(); + perror("Unable to read perf file descriptor\n"); + exit(-1); + } + + fcntl(perf_fd, F_SETFL, O_NONBLOCK); + + perf_mmap = mmap(NULL, (bufsize+1)*getpagesize(), + PROT_READ | PROT_WRITE, MAP_SHARED, perf_fd, 0); + if (perf_mmap == MAP_FAILED) { + fprintf(stderr, "failed to mmap with %d (%s)\n", errno, strerror(errno)); + return; + } + + ret = ioctl(perf_fd, PERF_EVENT_IOC_ENABLE, 0); + + if (ret < 0) { + fprintf(stderr, "failed to enable perf \n"); + } + + pc = (perf_event_mmap_page *)perf_mmap; + data_mmap = (unsigned char *)perf_mmap + getpagesize(); + + +} + +void perf_event::set_event_name(const char *event_name) +{ + free(name); + name = strdup(event_name); + if (!name) { + fprintf(stderr, "failed to allocate event name\n"); + return; + } + + char *c; + + c = strchr(name, ':'); + if (c) + *c = '/'; + + trace_type = get_trace_type(name); +} + +perf_event::~perf_event(void) +{ + free(name); + + if (perf_event::pevent->ref_count == 1) { + pevent_free(perf_event::pevent); + perf_event::pevent = NULL; + clear(); + } else + pevent_unref(perf_event::pevent); +} + +void perf_event::set_cpu(int _cpu) +{ + cpu = _cpu; +} + +static void allocate_pevent(void) +{ + if (!perf_event::pevent) + perf_event::pevent = pevent_alloc(); + else + pevent_ref(perf_event::pevent); +} + +perf_event::perf_event(const char *event_name, int _cpu, int buffer_size) +{ + allocate_pevent(); + name = NULL; + perf_fd = -1; + bufsize = buffer_size; + cpu = _cpu; + perf_mmap = NULL; + trace_type = 0; + set_event_name(event_name); +} + +perf_event::perf_event(void) +{ + allocate_pevent(); + name = NULL; + perf_fd = -1; + bufsize = 128; + perf_mmap = NULL; + cpu = 0; + trace_type = 0; +} + +void perf_event::start(void) +{ + create_perf_event(name, cpu); +} + +void perf_event::stop(void) +{ + int ret; + ret = ioctl(perf_fd, PERF_EVENT_IOC_DISABLE, 0); + if (ret) + cout << "stop failing\n"; +} + +void perf_event::process(void *cookie) +{ + struct perf_event_header *header; + + if (perf_fd < 0) + return; + + while (pc->data_tail != pc->data_head ) { + while (pc->data_tail >= (unsigned int)bufsize * getpagesize()) + pc->data_tail -= bufsize * getpagesize(); + + header = (struct perf_event_header *)( (unsigned char *)data_mmap + pc->data_tail); + + if (header->size == 0) + break; + + pc->data_tail += header->size; + + while (pc->data_tail >= (unsigned int)bufsize * getpagesize()) + pc->data_tail -= bufsize * getpagesize(); + + if (header->type == PERF_RECORD_SAMPLE) + handle_event(header, cookie); + } + pc->data_tail = pc->data_head; +} + +void perf_event::clear(void) +{ + if (perf_mmap) { +// memset(perf_mmap, 0, (bufsize)*getpagesize()); + munmap(perf_mmap, (bufsize+1)*getpagesize()); + perf_mmap = NULL; + } + if (perf_fd != -1) + close(perf_fd); + perf_fd = -1; +} |