diff options
| author | Raghavendra Rao Ananta <rananta@google.com> | 2021-10-07 23:34:35 +0000 |
|---|---|---|
| committer | Marc Zyngier <maz@kernel.org> | 2021-10-17 11:17:21 +0100 |
| commit | 414de89df1ec453ff4adb9d77ffd596096cb44bd (patch) | |
| tree | 7443b05ed3b99e4ef1ba6f2f9a9860450303b89e /tools/testing/selftests/kvm/lib | |
| parent | 17229bdc86c9e618e8832b5ca8451e367e07511b (diff) | |
KVM: arm64: selftests: Add light-weight spinlock support
Add a simpler version of spinlock support for ARM64 for
the guests to use.
The implementation is loosely based on the spinlock
implementation in kvm-unit-tests.
Signed-off-by: Raghavendra Rao Ananta <rananta@google.com>
Reviewed-by: Oliver Upton <oupton@google.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211007233439.1826892-12-rananta@google.com
Diffstat (limited to 'tools/testing/selftests/kvm/lib')
| -rw-r--r-- | tools/testing/selftests/kvm/lib/aarch64/spinlock.c | 27 |
1 files changed, 27 insertions, 0 deletions
diff --git a/tools/testing/selftests/kvm/lib/aarch64/spinlock.c b/tools/testing/selftests/kvm/lib/aarch64/spinlock.c new file mode 100644 index 000000000000..a076e780be5d --- /dev/null +++ b/tools/testing/selftests/kvm/lib/aarch64/spinlock.c @@ -0,0 +1,27 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * ARM64 Spinlock support + */ +#include <stdint.h> + +#include "spinlock.h" + +void spin_lock(struct spinlock *lock) +{ + int val, res; + + asm volatile( + "1: ldaxr %w0, [%2]\n" + " cbnz %w0, 1b\n" + " mov %w0, #1\n" + " stxr %w1, %w0, [%2]\n" + " cbnz %w1, 1b\n" + : "=&r" (val), "=&r" (res) + : "r" (&lock->v) + : "memory"); +} + +void spin_unlock(struct spinlock *lock) +{ + asm volatile("stlr wzr, [%0]\n" : : "r" (&lock->v) : "memory"); +} |