zed supports a '-M' cmdline opt to lock all pages in memory via
mlockall(). The _POSIX_MEMLOCK define is checked to determine whether
this function is supported. The current test assumes mlockall()
is supported if _POSIX_MEMLOCK is non-zero. However, this test is
insufficient according to mlock(2) and sysconf(3). If _POSIX_MEMLOCK
is -1, mlockall() is not supported; but if _POSIX_MEMLOCK is 0,
availability must be checked at runtime.
This commit adds an autoconf check for mlockall() to user.m4. The zed
code block for mlockall() is now guarded with a test for HAVE_MLOCKALL.
If defined, mlockall() will be called and its runtime availability
checked via its return value.
Signed-off-by: Chris Dunlap <cdunlap@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #2
static void
_lock_memory(void)
{
-#if ! _POSIX_MEMLOCK
- zed_log_die("Failed to lock memory pages: mlockall() not supported");
-
-#else /* _POSIX_MEMLOCK */
+#if HAVE_MLOCKALL
int i = 0;
const int max_tries = 10;
}
zed_log_die("Failed to lock memory pages: %s", strerror(errno));
-#endif /* _POSIX_MEMLOCK */
+#else /* HAVE_MLOCKALL */
+ zed_log_die("Failed to lock memory pages: mlockall() not supported");
+#endif /* HAVE_MLOCKALL */
}
/*
ZFS_AC_CONFIG_USER_LIBBLKID
ZFS_AC_CONFIG_USER_FRAME_LARGER_THAN
ZFS_AC_CONFIG_USER_RUNSTATEDIR
+dnl #
+dnl # Checks for library functions
+ AC_CHECK_FUNCS([mlockall])
])