From 76cb841cb886eef6b3bee341a2266c76578724ad Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Mon, 6 May 2024 03:02:30 +0200 Subject: Adding upstream version 4.19.249. Signed-off-by: Daniel Baumann --- arch/arm64/include/asm/sync_bitops.h | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) create mode 100644 arch/arm64/include/asm/sync_bitops.h (limited to 'arch/arm64/include/asm/sync_bitops.h') diff --git a/arch/arm64/include/asm/sync_bitops.h b/arch/arm64/include/asm/sync_bitops.h new file mode 100644 index 000000000..eee31a9f7 --- /dev/null +++ b/arch/arm64/include/asm/sync_bitops.h @@ -0,0 +1,27 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __ASM_SYNC_BITOPS_H__ +#define __ASM_SYNC_BITOPS_H__ + +#include +#include + +/* sync_bitops functions are equivalent to the SMP implementation of the + * original functions, independently from CONFIG_SMP being defined. + * + * We need them because _set_bit etc are not SMP safe if !CONFIG_SMP. But + * under Xen you might be communicating with a completely external entity + * who might be on another CPU (e.g. two uniprocessor guests communicating + * via event channels and grant tables). So we need a variant of the bit + * ops which are SMP safe even on a UP kernel. + */ + +#define sync_set_bit(nr, p) set_bit(nr, p) +#define sync_clear_bit(nr, p) clear_bit(nr, p) +#define sync_change_bit(nr, p) change_bit(nr, p) +#define sync_test_and_set_bit(nr, p) test_and_set_bit(nr, p) +#define sync_test_and_clear_bit(nr, p) test_and_clear_bit(nr, p) +#define sync_test_and_change_bit(nr, p) test_and_change_bit(nr, p) +#define sync_test_bit(nr, addr) test_bit(nr, addr) +#define sync_cmpxchg cmpxchg + +#endif -- cgit v1.2.3