Move all sources to 'src/'

[lttng-ust.git] / src / liblttng-ust / lttng-getcpu.c

diff --git a/src/liblttng-ust/lttng-getcpu.c b/src/liblttng-ust/lttng-getcpu.c
new file mode 100644 (file)
index 0000000..762f815
--- /dev/null
+++ b/src/liblttng-ust/lttng-getcpu.c
@@ -0,0 +1,55 @@
+/*
+ * SPDX-License-Identifier: LGPL-2.1-only
+ *
+ * Copyright (C) 2014 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ */
+
+#define _LGPL_SOURCE
+#include <error.h>
+#include <dlfcn.h>
+#include <stdlib.h>
+#include <usterr-signal-safe.h>
+#include <lttng/ust-getcpu.h>
+#include <urcu/system.h>
+#include <urcu/arch.h>
+
+#include "getenv.h"
+#include "../libringbuffer/getcpu.h"
+
+int (*lttng_get_cpu)(void);
+
+static
+void *getcpu_handle;
+
+int lttng_ust_getcpu_override(int (*getcpu)(void))
+{
+       CMM_STORE_SHARED(lttng_get_cpu, getcpu);
+       return 0;
+}
+
+void lttng_ust_getcpu_init(void)
+{
+       const char *libname;
+       void (*libinit)(void);
+
+       if (getcpu_handle)
+               return;
+       libname = lttng_ust_getenv("LTTNG_UST_GETCPU_PLUGIN");
+       if (!libname)
+               return;
+       getcpu_handle = dlopen(libname, RTLD_NOW);
+       if (!getcpu_handle) {
+               PERROR("Cannot load LTTng UST getcpu override library %s",
+                       libname);
+               return;
+       }
+       dlerror();
+       libinit = (void (*)(void)) dlsym(getcpu_handle,
+               "lttng_ust_getcpu_plugin_init");
+       if (!libinit) {
+               PERROR("Cannot find LTTng UST getcpu override library %s initialization function lttng_ust_getcpu_plugin_init()",
+                       libname);
+               return;
+       }
+       libinit();
+}