mirror/mariadb
1
0
Fork 0
mirror of https://github.com/MariaDB/server.git synced 2025-02-01 11:31:51 +01:00
Code Issues Projects Releases Packages Wiki Activity Actions

branches/zip:

Browse source 
Implement a check whether pthread_t objects can be used by GCC atomic
builtin functions. This check is implemented in plug.in and defines the
macro HAVE_ATOMIC_PTHREAD_T. This macro is checked in univ.i and the
relevant part of the code enabled (the one that uses GCC atomics against
pthread_t objects).

In addition to this, the same program that is compiled as part of the
plug.in check is added in ut/ut0auxconf.c. In the InnoDB Plugin source
archives that are shipped to the users, a generated Makefile.in is added.
That Makefile.in will be modified to compile ut/ut0auxconf.c and define
the macro HAVE_ATOMIC_PTHREAD_T if the compilation succeeds. I.e.
Makefile.in will emulate the work that is done by plug.in. This is done in
order to make the check happen and HAVE_ATOMIC_PTHREAD_T eventually
defined without regenerating MySQL's ./configure from
./storage/innobase/plug.in. The point is not to ask users to install the
autotools and regenerate ./configure.

rb://95

Approved by:	Marko
This commit is contained in:
vasil 2009-03-05 14:38:59 +00:00
parent 584f4cea77
commit 3c9bec1100
4 changed files with 64 additions and 3 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

16
include/univ.i
View file

@ -116,10 +116,20 @@ of the 32-bit x86 assembler in mutex operations. */
/* For InnoDB rw_locks to work with atomics we need the thread_id
to be no more than machine word wide. The following enables using
atomics for InnoDB rw_locks where these conditions are met. */
# if defined(HAVE_GCC_ATOMIC_BUILTINS) && (defined(__linux__) \
|| defined(__FreeBSD__))
#ifdef HAVE_GCC_ATOMIC_BUILTINS
/* if HAVE_ATOMIC_PTHREAD_T is defined at this point that means that
the code from plug.in has defined it and we do not need to include
ut0auxconf.h which would either define HAVE_ATOMIC_PTHREAD_T or will
be empty */
# ifndef HAVE_ATOMIC_PTHREAD_T
# include "ut0auxconf.h"
# endif /* HAVE_ATOMIC_PTHREAD_T */
/* now HAVE_ATOMIC_PTHREAD_T is eventually defined either by plug.in or
from Makefile.in->ut0auxconf.h */
# ifdef HAVE_ATOMIC_PTHREAD_T
# define INNODB_RW_LOCKS_USE_ATOMICS
# endif
# endif /* HAVE_ATOMIC_PTHREAD_T */
#endif /* HAVE_GCC_ATOMIC_BUILTINS */
/* We only try to do explicit inlining of functions with gcc and
Microsoft Visual C++ */

14
include/ut0auxconf.h Normal file
View file

@ -0,0 +1,14 @@
/* Do not remove this file even though it is empty.
This file is included in univ.i and will cause compilation failure
if not present.
A custom check has been added in the generated
storage/innobase/Makefile.in that is shipped with with the InnoDB Plugin
source archive. This check tries to compile a test program and if
successful then adds "#define HAVE_ATOMIC_PTHREAD_T" to this file.
This is a hack that has been developed in order to check for pthread_t
atomicity without the need to regenerate the ./configure script that is
distributed in the MySQL 5.1 official source archives.
If by any chance Makefile.in and ./configure are regenerated and thus
the hack from Makefile.in wiped away then the "real" check from plug.in
will take over.
*/

24
plug.in
View file

@ -51,6 +51,30 @@ MYSQL_PLUGIN_ACTIONS(innobase, [
;;
esac
AC_SUBST(INNODB_DYNAMIC_CFLAGS)
AC_MSG_CHECKING(whether pthread_t can be used by GCC atomic builtins)
AC_TRY_RUN(
[
#include <pthread.h>
int main(int argc, char** argv) {
pthread_t x1;
pthread_t x2;
pthread_t x3;
__sync_bool_compare_and_swap(&x1, x2, x3);
return(0);
}
],
[
AC_DEFINE([HAVE_ATOMIC_PTHREAD_T], [1],
[pthread_t can be used by GCC atomic builtins])
AC_MSG_RESULT(yes)
],
[
AC_MSG_RESULT(no)
]
)
])
# vim: set ft=config:

13
ut/ut0auxconf.c Normal file
View file

@ -0,0 +1,13 @@
#include <pthread.h>
int
main(int argc, char** argv)
{
pthread_t x1;
pthread_t x2;
pthread_t x3;
__sync_bool_compare_and_swap(&x1, x2, x3);
return(0);
}