diff mbox series

[v3,06/11] s390: Add clear_bit_unlock_is_negative_byte implementation

Message ID 20200416220130.13343-7-willy@infradead.org (mailing list archive)
State New, archived
Headers show
Series Make PageWriteback use the PageLocked optimisation | expand

Commit Message

Matthew Wilcox April 16, 2020, 10:01 p.m. UTC 
From: "Matthew Wilcox (Oracle)" <willy@infradead.org>

This is the generic implementation.  I can't figure out an optimised
implementation for s390.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: linux-s390@vger.kernel.org
---
 arch/s390/include/asm/bitops.h | 9 +++++++++
 1 file changed, 9 insertions(+)
diff mbox series

Patch

diff --git a/arch/s390/include/asm/bitops.h b/arch/s390/include/asm/bitops.h
index 431e208a5ea4..d313ca6affaf 100644
--- a/arch/s390/include/asm/bitops.h
+++ b/arch/s390/include/asm/bitops.h
@@ -241,6 +241,15 @@  static inline void arch___clear_bit_unlock(unsigned long nr,
 	arch___clear_bit(nr, ptr);
 }
 
+static inline bool arch_clear_bit_unlock_is_negative_byte(unsigned int nr,
+						volatile unsigned long *p)
+{
+	arch_clear_bit_unlock(nr, p);
+	return arch_test_bit(7, p);
+}
+#define arch_clear_bit_unlock_is_negative_byte \
+	arch_clear_bit_unlock_is_negative_byte
+
 #include <asm-generic/bitops/instrumented-atomic.h>
 #include <asm-generic/bitops/instrumented-non-atomic.h>
 #include <asm-generic/bitops/instrumented-lock.h>