Commit | Line | Data |
---|---|---|
8b3bd7a3 | 1 | /* |
ab5be9fa | 2 | * Copyright (C) 2012 Simon Marchi <simon.marchi@polymtl.ca> |
8b3bd7a3 | 3 | * |
ab5be9fa | 4 | * SPDX-License-Identifier: GPL-2.0-only |
8b3bd7a3 | 5 | * |
8b3bd7a3 SM |
6 | */ |
7 | ||
6c1c0768 | 8 | #define _LGPL_SOURCE |
8b3bd7a3 SM |
9 | #include <stddef.h> |
10 | #include <unistd.h> | |
1a1a34b4 MJ |
11 | #include <stdbool.h> |
12 | #include <sys/resource.h> | |
13 | #include <pthread.h> | |
8b3bd7a3 SM |
14 | |
15 | #include "defaults.h" | |
16 | #include "macros.h" | |
1a1a34b4 MJ |
17 | #include "error.h" |
18 | ||
4d5fb75f | 19 | static int pthread_attr_init_done; |
1a1a34b4 | 20 | static pthread_attr_t tattr; |
8b3bd7a3 | 21 | |
81663f07 MJ |
22 | static size_t get_page_size(void) |
23 | { | |
24 | const long ret = sysconf(_SC_PAGE_SIZE); | |
25 | ||
26 | if (ret < 0) { | |
27 | /* | |
28 | * Fatal error since there is no safe way to recover from this. | |
29 | */ | |
30 | PERROR("Failed to get system page size using sysconf(_SC_PAGE_SIZE)"); | |
31 | abort(); | |
32 | } | |
33 | ||
34 | return (size_t) ret; | |
35 | } | |
36 | ||
78d8fb4f | 37 | size_t default_get_channel_subbuf_size(void) |
8b3bd7a3 | 38 | { |
81663f07 | 39 | return max(_DEFAULT_CHANNEL_SUBBUF_SIZE, get_page_size()); |
78d8fb4f JG |
40 | } |
41 | ||
78d8fb4f JG |
42 | size_t default_get_metadata_subbuf_size(void) |
43 | { | |
81663f07 | 44 | return max(DEFAULT_METADATA_SUBBUF_SIZE, get_page_size()); |
78d8fb4f JG |
45 | } |
46 | ||
78d8fb4f JG |
47 | size_t default_get_kernel_channel_subbuf_size(void) |
48 | { | |
81663f07 | 49 | return max(DEFAULT_KERNEL_CHANNEL_SUBBUF_SIZE, get_page_size()); |
78d8fb4f JG |
50 | } |
51 | ||
78d8fb4f JG |
52 | size_t default_get_ust_pid_channel_subbuf_size(void) |
53 | { | |
81663f07 | 54 | return max(DEFAULT_UST_PID_CHANNEL_SUBBUF_SIZE, get_page_size()); |
78d8fb4f JG |
55 | } |
56 | ||
78d8fb4f JG |
57 | size_t default_get_ust_uid_channel_subbuf_size(void) |
58 | { | |
81663f07 | 59 | return max(DEFAULT_UST_UID_CHANNEL_SUBBUF_SIZE, get_page_size()); |
8b3bd7a3 | 60 | } |
1a1a34b4 | 61 | |
1a1a34b4 MJ |
62 | pthread_attr_t *default_pthread_attr(void) |
63 | { | |
4d5fb75f JG |
64 | if (pthread_attr_init_done) { |
65 | return &tattr; | |
66 | } | |
1a1a34b4 | 67 | |
b38afa27 | 68 | WARN("Uninitialized pthread attributes, using libc defaults."); |
4d5fb75f JG |
69 | return NULL; |
70 | } | |
1a1a34b4 | 71 | |
4d5fb75f JG |
72 | static void __attribute__((constructor)) init_default_pthread_attr(void) |
73 | { | |
74 | int ret; | |
75 | struct rlimit rlim; | |
76 | size_t pthread_ss, system_ss, selected_ss; | |
77 | ||
78 | ret = pthread_attr_init(&tattr); | |
79 | if (ret) { | |
80 | errno = ret; | |
81 | PERROR("pthread_attr_init"); | |
82 | goto error; | |
1a1a34b4 MJ |
83 | } |
84 | ||
85 | /* Get system stack size limits. */ | |
86 | ret = getrlimit(RLIMIT_STACK, &rlim); | |
87 | if (ret < 0) { | |
88 | PERROR("getrlimit"); | |
4d5fb75f | 89 | goto error_destroy; |
1a1a34b4 MJ |
90 | } |
91 | DBG("Stack size limits: soft %lld, hard %lld bytes", | |
92 | (long long) rlim.rlim_cur, | |
93 | (long long) rlim.rlim_max); | |
94 | ||
4d5fb75f JG |
95 | /* |
96 | * getrlimit() may return a stack size of "-1", meaning "unlimited". | |
97 | * In this case, we impose a known-good default minimum value which will | |
98 | * override the libc's default stack size if it is smaller. | |
99 | */ | |
100 | system_ss = rlim.rlim_cur != -1 ? rlim.rlim_cur : | |
101 | DEFAULT_LTTNG_THREAD_STACK_SIZE; | |
102 | ||
1a1a34b4 | 103 | /* Get pthread default thread stack size. */ |
4d5fb75f | 104 | ret = pthread_attr_getstacksize(&tattr, &pthread_ss); |
1a1a34b4 MJ |
105 | if (ret < 0) { |
106 | PERROR("pthread_attr_getstacksize"); | |
4d5fb75f | 107 | goto error_destroy; |
1a1a34b4 | 108 | } |
4d5fb75f JG |
109 | DBG("Default pthread stack size is %zu bytes", pthread_ss); |
110 | ||
111 | selected_ss = max_t(size_t, pthread_ss, system_ss); | |
112 | if (selected_ss < DEFAULT_LTTNG_THREAD_STACK_SIZE) { | |
113 | DBG("Default stack size is too small, setting it to %zu bytes", | |
114 | (size_t) DEFAULT_LTTNG_THREAD_STACK_SIZE); | |
115 | selected_ss = DEFAULT_LTTNG_THREAD_STACK_SIZE; | |
1a1a34b4 MJ |
116 | } |
117 | ||
89e06fb5 | 118 | if (rlim.rlim_max > 0 && selected_ss > rlim.rlim_max) { |
0d43a013 | 119 | WARN("Your system's stack size restrictions (%zu bytes) may be too low for the LTTng daemons to function properly, please set the stack size limit to at least %zu bytes to ensure reliable operation", |
4d5fb75f JG |
120 | (size_t) rlim.rlim_max, (size_t) DEFAULT_LTTNG_THREAD_STACK_SIZE); |
121 | selected_ss = (size_t) rlim.rlim_max; | |
122 | } | |
123 | ||
124 | ret = pthread_attr_setstacksize(&tattr, selected_ss); | |
125 | if (ret < 0) { | |
126 | PERROR("pthread_attr_setstacksize"); | |
127 | goto error_destroy; | |
128 | } | |
129 | pthread_attr_init_done = 1; | |
1a1a34b4 | 130 | error: |
4d5fb75f JG |
131 | return; |
132 | error_destroy: | |
133 | ret = pthread_attr_destroy(&tattr); | |
134 | if (ret) { | |
135 | errno = ret; | |
136 | PERROR("pthread_attr_destroy"); | |
137 | } | |
138 | } | |
139 | ||
140 | static void __attribute__((destructor)) fini_default_pthread_attr(void) | |
141 | { | |
142 | int ret; | |
143 | ||
144 | if (!pthread_attr_init_done) { | |
145 | return; | |
146 | } | |
147 | ||
148 | ret = pthread_attr_destroy(&tattr); | |
149 | if (ret) { | |
150 | errno = ret; | |
151 | PERROR("pthread_attr_destroy"); | |
152 | } | |
1a1a34b4 | 153 | } |