| 1 | /* |
| 2 | * SPDX-License-Identifier: LGPL-2.1-only |
| 3 | * |
| 4 | * Copyright (C) 2014 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
| 5 | */ |
| 6 | |
| 7 | #define _LGPL_SOURCE |
| 8 | #include <error.h> |
| 9 | #include <dlfcn.h> |
| 10 | #include <stdlib.h> |
| 11 | #include "common/logging.h" |
| 12 | #include <lttng/ust-getcpu.h> |
| 13 | #include <urcu/system.h> |
| 14 | #include <urcu/arch.h> |
| 15 | |
| 16 | #include "getenv.h" |
| 17 | #include "../libringbuffer/getcpu.h" |
| 18 | |
| 19 | int (*lttng_get_cpu)(void); |
| 20 | |
| 21 | static |
| 22 | void *getcpu_handle; |
| 23 | |
| 24 | int lttng_ust_getcpu_override(int (*getcpu)(void)) |
| 25 | { |
| 26 | CMM_STORE_SHARED(lttng_get_cpu, getcpu); |
| 27 | return 0; |
| 28 | } |
| 29 | |
| 30 | void lttng_ust_getcpu_init(void) |
| 31 | { |
| 32 | const char *libname; |
| 33 | void (*libinit)(void); |
| 34 | |
| 35 | if (getcpu_handle) |
| 36 | return; |
| 37 | libname = lttng_ust_getenv("LTTNG_UST_GETCPU_PLUGIN"); |
| 38 | if (!libname) |
| 39 | return; |
| 40 | getcpu_handle = dlopen(libname, RTLD_NOW); |
| 41 | if (!getcpu_handle) { |
| 42 | PERROR("Cannot load LTTng UST getcpu override library %s", |
| 43 | libname); |
| 44 | return; |
| 45 | } |
| 46 | dlerror(); |
| 47 | libinit = (void (*)(void)) dlsym(getcpu_handle, |
| 48 | "lttng_ust_getcpu_plugin_init"); |
| 49 | if (!libinit) { |
| 50 | PERROR("Cannot find LTTng UST getcpu override library %s initialization function lttng_ust_getcpu_plugin_init()", |
| 51 | libname); |
| 52 | return; |
| 53 | } |
| 54 | libinit(); |
| 55 | } |