[RFC PATCH v2 02/12] m68k: Don't use asm-generic/bitops/lock.h

From: Will Deacon
Date: Mon Feb 26 2018 - 10:05:52 EST


asm-generic/bitops/lock.h is shortly going to be built on top of the
atomic_long_* API, which introduces a nasty circular dependency for
m68k where linux/atomic.h pulls in linux/bitops.h via:

linux/atomic.h
asm/atomic.h
linux/irqflags.h
asm/irqflags.h
linux/preempt.h
asm/preempt.h
asm-generic/preempt.h
linux/thread_info.h
asm/thread_info.h
asm/page.h
asm-generic/getorder.h
linux/log2.h
linux/bitops.h

Since m68k isn't SMP and doesn't support ACQUIRE/RELEASE barriers, we
can just define the lock bitops in terms of the atomic bitops in the
asm/bitops.h header.

Acked-by: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
Signed-off-by: Will Deacon <will.deacon@xxxxxxx>
---
arch/m68k/include/asm/bitops.h | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/arch/m68k/include/asm/bitops.h b/arch/m68k/include/asm/bitops.h
index 93b47b1f6fb4..18193419f97d 100644
--- a/arch/m68k/include/asm/bitops.h
+++ b/arch/m68k/include/asm/bitops.h
@@ -515,12 +515,16 @@ static inline int __fls(int x)

#endif

+/* Simple test-and-set bit locks */
+#define test_and_set_bit_lock test_and_set_bit
+#define clear_bit_unlock clear_bit
+#define __clear_bit_unlock clear_bit_unlock
+
#include <asm-generic/bitops/ext2-atomic.h>
#include <asm-generic/bitops/le.h>
#include <asm-generic/bitops/fls64.h>
#include <asm-generic/bitops/sched.h>
#include <asm-generic/bitops/hweight.h>
-#include <asm-generic/bitops/lock.h>
#endif /* __KERNEL__ */

#endif /* _M68K_BITOPS_H */
--
2.1.4