lockref: use BLOATED_SPINLOCKS to avoid explicit config dependencies
Avoid the fragile Kconfig construct guestimating spinlock_t sizes; use a
friendly compile-time test to determine this.
[[email protected]: drop CONFIG_CMPXCHG_LOCKREF]
Signed-off-by: Peter Zijlstra <[email protected]>
Signed-off-by: Kirill A. Shutemov <[email protected]>
Cc: Ingo Molnar <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
diff --git a/include/linux/lockref.h b/include/linux/lockref.h
index 13dfd36..c8929c3 100644
--- a/include/linux/lockref.h
+++ b/include/linux/lockref.h
@@ -15,10 +15,15 @@
*/
#include <linux/spinlock.h>
+#include <generated/bounds.h>
+
+#define USE_CMPXCHG_LOCKREF \
+ (IS_ENABLED(CONFIG_ARCH_USE_CMPXCHG_LOCKREF) && \
+ IS_ENABLED(CONFIG_SMP) && !BLOATED_SPINLOCKS)
struct lockref {
union {
-#ifdef CONFIG_CMPXCHG_LOCKREF
+#if USE_CMPXCHG_LOCKREF
aligned_u64 lock_count;
#endif
struct {
diff --git a/lib/Kconfig b/lib/Kconfig
index 75485e16..06dc742 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -51,13 +51,6 @@
config ARCH_USE_CMPXCHG_LOCKREF
bool
-config CMPXCHG_LOCKREF
- def_bool y if ARCH_USE_CMPXCHG_LOCKREF
- depends on SMP
- depends on !GENERIC_LOCKBREAK
- depends on !DEBUG_SPINLOCK
- depends on !DEBUG_LOCK_ALLOC
-
config CRC_CCITT
tristate "CRC-CCITT functions"
help
diff --git a/lib/lockref.c b/lib/lockref.c
index af6e95d..d2b123f 100644
--- a/lib/lockref.c
+++ b/lib/lockref.c
@@ -1,7 +1,7 @@
#include <linux/export.h>
#include <linux/lockref.h>
-#ifdef CONFIG_CMPXCHG_LOCKREF
+#if USE_CMPXCHG_LOCKREF
/*
* Allow weakly-ordered memory architectures to provide barrier-less
