[V2 08/11] tools: Add atomic_test_and_set_bit()

Peter Gonda
2022-08-01T20:12:22Z

atomic_test_and_set_bit() allows for atomic bitmap usage from KVM
selftests.

Signed-off-by: Peter Gonda <pgonda@google.com>
Suggested-by: Sean Christopherson <seanjc@google.com>
---
tools/arch/x86/include/asm/atomic.h | 7 +++++++
1 file changed, 7 insertions(+)

diff --git a/tools/arch/x86/include/asm/atomic.h b/tools/arch/x86/include/asm/atomic.h
index 1f5e26aae9fc..01cc27ec4520 100644
--- a/tools/arch/x86/include/asm/atomic.h
+++ b/tools/arch/x86/include/asm/atomic.h
@@ -8,6 +8,7 @@

#define LOCK_PREFIX "\n\tlock; "

+#include <asm/asm.h>
#include <asm/cmpxchg.h>

/*
@@ -70,4 +71,10 @@ static __always_inline int atomic_cmpxchg(atomic_t *v, int old, int new)
return cmpxchg(&v->counter, old, new);
}

+static inline int atomic_test_and_set_bit(long nr, unsigned long *addr)
+{
+ GEN_BINARY_RMWcc(LOCK_PREFIX __ASM_SIZE(bts), *addr, "Ir", nr, "%0", "c");
+
+}
+
#endif /* _TOOLS_LINUX_ASM_X86_ATOMIC_H */
--
2.37.1.455.g008518b4e5-goog