[PATCH] lightweight robust futexes: core
Add the core infrastructure for robust futexes: structure definitions, the new
syscalls and the do_exit() based cleanup mechanism.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Acked-by: Ulrich Drepper <drepper@redhat.com>
Cc: Michael Kerrisk <mtk-manpages@gmx.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/include/linux/threads.h b/include/linux/threads.h
index b59738a..e646bcd 100644
--- a/include/linux/threads.h
+++ b/include/linux/threads.h
@@ -28,7 +28,8 @@
#define PID_MAX_DEFAULT (CONFIG_BASE_SMALL ? 0x1000 : 0x8000)
/*
- * A maximum of 4 million PIDs should be enough for a while:
+ * A maximum of 4 million PIDs should be enough for a while.
+ * [NOTE: PID/TIDs are limited to 2^29 ~= 500+ million, see futex.h.]
*/
#define PID_MAX_LIMIT (CONFIG_BASE_SMALL ? PAGE_SIZE * 8 : \
(sizeof(long) > 4 ? 4 * 1024 * 1024 : PID_MAX_DEFAULT))