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,enum psi_resource resource)36 int init_psi_monitor(enum psi_stall_type stall_type, int threshold_us, int window_us,
37 enum psi_resource resource) {
38 if (resource < PSI_MEMORY || resource >= PSI_RESOURCE_COUNT) {
39 ALOGE("Invalid psi resource type: %d", resource);
40 errno = EINVAL;
41 return -1;
42 }
43 int fd;
44 int res;
45 char buf[256];
46
47 fd = TEMP_FAILURE_RETRY(open(psi_resource_file[resource], O_WRONLY | O_CLOEXEC));
48 if (fd < 0) {
49 ALOGE("No kernel psi monitor support (errno=%d)", errno);
50 return -1;
51 }
52
53 switch (stall_type) {
54 case (PSI_SOME):
55 case (PSI_FULL):
56 res = snprintf(buf, sizeof(buf), "%s %d %d",
57 stall_type_name[stall_type], threshold_us, window_us);
58 break;
59 default:
60 ALOGE("Invalid psi stall type: %d", stall_type);
61 errno = EINVAL;
62 goto err;
63 }
64
65 if (res >= (ssize_t)sizeof(buf)) {
66 ALOGE("%s line overflow for psi stall type '%s'", psi_resource_file[resource],
67 stall_type_name[stall_type]);
68 errno = EINVAL;
69 goto err;
70 }
71
72 res = TEMP_FAILURE_RETRY(write(fd, buf, strlen(buf) + 1));
73 if (res < 0) {
74 ALOGE("%s write failed for psi stall type '%s'; errno=%d", psi_resource_file[resource],
75 stall_type_name[stall_type], errno);
76 goto err;
77 }
78
79 return fd;
80
81 err:
82 close(fd);
83 return -1;
84 }
85
register_psi_monitor(int epollfd,int fd,void * data)86 int register_psi_monitor(int epollfd, int fd, void* data) {
87 int res;
88 struct epoll_event epev;
89
90 epev.events = EPOLLPRI;
91 epev.data.ptr = data;
92 res = epoll_ctl(epollfd, EPOLL_CTL_ADD, fd, &epev);
93 if (res < 0) {
94 ALOGE("epoll_ctl for psi monitor failed; errno=%d", errno);
95 }
96 return res;
97 }
98
unregister_psi_monitor(int epollfd,int fd)99 int unregister_psi_monitor(int epollfd, int fd) {
100 return epoll_ctl(epollfd, EPOLL_CTL_DEL, fd, NULL);
101 }
102
destroy_psi_monitor(int fd)103 void destroy_psi_monitor(int fd) {
104 if (fd >= 0) {
105 close(fd);
106 }
107 }
108
parse_psi_line(char * line,enum psi_stall_type stall_type,struct psi_stats stats[])109 int parse_psi_line(char *line, enum psi_stall_type stall_type, struct psi_stats stats[]) {
110 char type_name[5];
111 struct psi_stats *stat = &stats[stall_type];
112
113 if (!line || sscanf(line, "%4s avg10=%f avg60=%f avg300=%f total=%lu",
114 type_name, &stat->avg10, &stat->avg60, &stat->avg300, &stat->total) != 5) {
115 return -1;
116 }
117 if (strcmp(type_name, stall_type_name[stall_type])) {
118 return -1;
119 }
120 return 0;
121 }
122