1 /*
2 * Copyright (C) 2018 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #define LOG_TAG "libpsi"
18
19 #include <errno.h>
20 #include <fcntl.h>
21 #include <stdio.h>
22 #include <string.h>
23 #include <sys/epoll.h>
24 #include <unistd.h>
25
26 #include <log/log.h>
27 #include <cutils/fs.h>
28 #include <stdio.h>
29 #include "psi/psi.h"
30
31 static const char* stall_type_name[] = {
32 "some",
33 "full",
34 };
35
init_psi_monitor(enum psi_stall_type stall_type,int threshold_us,int window_us)36 int init_psi_monitor(enum psi_stall_type stall_type,
37 int threshold_us, int window_us) {
38 int fd;
39 int res;
40 char buf[256];
41
42 fd = TEMP_FAILURE_RETRY(open(PSI_PATH_MEMORY, O_WRONLY | O_CLOEXEC));
43 if (fd < 0) {
44 ALOGE("No kernel psi monitor support (errno=%d)", errno);
45 return -1;
46 }
47
48 switch (stall_type) {
49 case (PSI_SOME):
50 case (PSI_FULL):
51 res = snprintf(buf, sizeof(buf), "%s %d %d",
52 stall_type_name[stall_type], threshold_us, window_us);
53 break;
54 default:
55 ALOGE("Invalid psi stall type: %d", stall_type);
56 errno = EINVAL;
57 goto err;
58 }
59
60 if (res >= (ssize_t)sizeof(buf)) {
61 ALOGE("%s line overflow for psi stall type '%s'",
62 PSI_PATH_MEMORY, stall_type_name[stall_type]);
63 errno = EINVAL;
64 goto err;
65 }
66
67 res = TEMP_FAILURE_RETRY(write(fd, buf, strlen(buf) + 1));
68 if (res < 0) {
69 ALOGE("%s write failed for psi stall type '%s'; errno=%d",
70 PSI_PATH_MEMORY, stall_type_name[stall_type], errno);
71 goto err;
72 }
73
74 return fd;
75
76 err:
77 close(fd);
78 return -1;
79 }
80
register_psi_monitor(int epollfd,int fd,void * data)81 int register_psi_monitor(int epollfd, int fd, void* data) {
82 int res;
83 struct epoll_event epev;
84
85 epev.events = EPOLLPRI;
86 epev.data.ptr = data;
87 res = epoll_ctl(epollfd, EPOLL_CTL_ADD, fd, &epev);
88 if (res < 0) {
89 ALOGE("epoll_ctl for psi monitor failed; errno=%d", errno);
90 }
91 return res;
92 }
93
unregister_psi_monitor(int epollfd,int fd)94 int unregister_psi_monitor(int epollfd, int fd) {
95 return epoll_ctl(epollfd, EPOLL_CTL_DEL, fd, NULL);
96 }
97
destroy_psi_monitor(int fd)98 void destroy_psi_monitor(int fd) {
99 if (fd >= 0) {
100 close(fd);
101 }
102 }
103
parse_psi_line(char * line,enum psi_stall_type stall_type,struct psi_stats stats[])104 int parse_psi_line(char *line, enum psi_stall_type stall_type, struct psi_stats stats[]) {
105 char type_name[5];
106 struct psi_stats *stat = &stats[stall_type];
107
108 if (!line || sscanf(line, "%4s avg10=%f avg60=%f avg300=%f total=%lu",
109 type_name, &stat->avg10, &stat->avg60, &stat->avg300, &stat->total) != 5) {
110 return -1;
111 }
112 if (strcmp(type_name, stall_type_name[stall_type])) {
113 return -1;
114 }
115 return 0;
116 }
117