MDEV-23091: perfschema Add support for OpenBSD's getthrid() to retrieve the thread id

storage/perfschema/CMakeLists.txt

@@ -298,6 +298,16 @@ int main(int ac, char **av)
 }"
 HAVE_SYS_GETTID)
 
+# Check for getthrid()
+CHECK_C_SOURCE_COMPILES("
+#include <unistd.h>
+int main(int ac, char **av)
+{
+  unsigned long long tid = getthrid();
+  return (tid != 0 ? 0 : 1);
+}"
+HAVE_GETTHRID)
+
 # Check for pthread_getthreadid_np()
 CHECK_C_SOURCE_COMPILES("
 #include <pthread_np.h>

storage/perfschema/my_thread.h

@@ -67,6 +67,10 @@ static inline my_thread_os_id_t my_thread_os_id()
   /* FreeBSD 10.2 */
   return pthread_getthreadid_np();
 #else
+#ifdef HAVE_GETTHRID
+  /* OpenBSD */
+  return getthrid();
+#else
 #ifdef HAVE_INTEGER_PTHREAD_SELF
   /* Unknown platform, fallback. */
   return pthread_self();
@@ -74,6 +78,7 @@ static inline my_thread_os_id_t my_thread_os_id()
   /* Feature not available. */
   return 0;
 #endif /* HAVE_INTEGER_PTHREAD_SELF */
+#endif /* HAVE_GETTHRID */
 #endif /* HAVE_PTHREAD_GETTHREADID_NP */
 #endif /* _WIN32 */
 #endif /* HAVE_SYS_GETTID */

storage/perfschema/pfs_config.h.cmake

 #cmakedefine HAVE_PTHREAD_THREADID_NP 1
 #cmakedefine HAVE_SYS_GETTID 1
+#cmakedefine HAVE_GETTHRID 1
 #cmakedefine HAVE_PTHREAD_GETTHREADID_NP 1
 #cmakedefine HAVE_INTEGER_PTHREAD_SELF 1