[RFC V1 07/10] tools: Add atomic_test_and_set_bit()

From: Peter Gonda <pgonda@google.com>
To: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org, marcorr@google.com,
	seanjc@google.com, michael.roth@amd.com, thomas.lendacky@amd.com,
	joro@8bytes.org, mizhang@google.com, pbonzini@redhat.com,
	Peter Gonda <pgonda@google.com>
Subject: [RFC V1 07/10] tools: Add atomic_test_and_set_bit()
Date: Fri, 15 Jul 2022 12:29:53 -0700	[thread overview]
Message-ID: <20220715192956.1873315-9-pgonda@google.com> (raw)
In-Reply-To: <20220715192956.1873315-1-pgonda@google.com>

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..45ea15c98957 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, volatile unsigned long *addr)
+{
+	GEN_BINARY_RMWcc(LOCK_PREFIX __ASM_SIZE(bts), *addr, "Ir", nr, "%0", "c");
+
+}
+
 #endif /* _TOOLS_LINUX_ASM_X86_ATOMIC_H */
-- 
2.37.0.170.g444d1eabd0-goog

