| Message ID | 20210901211412.4171835-9-rananta@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KVM: arm64: selftests: Introduce arch_timer selftest | expand |
On Wed, Sep 1, 2021 at 2:14 PM Raghavendra Rao Ananta <rananta@google.com> wrote: > > 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> > --- > tools/testing/selftests/kvm/Makefile | 2 +- > .../selftests/kvm/include/aarch64/spinlock.h | 13 +++++++++ > .../selftests/kvm/lib/aarch64/spinlock.c | 27 +++++++++++++++++++ > 3 files changed, 41 insertions(+), 1 deletion(-) > create mode 100644 tools/testing/selftests/kvm/include/aarch64/spinlock.h > create mode 100644 tools/testing/selftests/kvm/lib/aarch64/spinlock.c > > diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile > index 5d05801ab816..61f0d376af99 100644 > --- a/tools/testing/selftests/kvm/Makefile > +++ b/tools/testing/selftests/kvm/Makefile > @@ -35,7 +35,7 @@ endif > > LIBKVM = lib/assert.c lib/elf.c lib/io.c lib/kvm_util.c lib/rbtree.c lib/sparsebit.c lib/test_util.c lib/guest_modes.c lib/perf_test_util.c > LIBKVM_x86_64 = lib/x86_64/apic.c lib/x86_64/processor.c lib/x86_64/vmx.c lib/x86_64/svm.c lib/x86_64/ucall.c lib/x86_64/handlers.S > -LIBKVM_aarch64 = lib/aarch64/processor.c lib/aarch64/ucall.c lib/aarch64/handlers.S > +LIBKVM_aarch64 = lib/aarch64/processor.c lib/aarch64/ucall.c lib/aarch64/handlers.S lib/aarch64/spinlock.c > LIBKVM_s390x = lib/s390x/processor.c lib/s390x/ucall.c lib/s390x/diag318_test_handler.c > > TEST_GEN_PROGS_x86_64 = x86_64/cr4_cpuid_sync_test > diff --git a/tools/testing/selftests/kvm/include/aarch64/spinlock.h b/tools/testing/selftests/kvm/include/aarch64/spinlock.h > new file mode 100644 > index 000000000000..cf0984106d14 > --- /dev/null > +++ b/tools/testing/selftests/kvm/include/aarch64/spinlock.h > @@ -0,0 +1,13 @@ > +/* SPDX-License-Identifier: GPL-2.0 */ > + > +#ifndef SELFTEST_KVM_ARM64_SPINLOCK_H > +#define SELFTEST_KVM_ARM64_SPINLOCK_H > + > +struct spinlock { > + int v; > +}; > + > +extern void spin_lock(struct spinlock *lock); > +extern void spin_unlock(struct spinlock *lock); > + > +#endif /* SELFTEST_KVM_ARM64_SPINLOCK_H */ > 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..6d66a3dac237 > --- /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) > +{ > + uint32_t val, res; nit: use 'int' to match the lock value type. > + > + 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"); > +} > -- > 2.33.0.153.gba50c8fa24-goog > Otherwise, LGTM. Reviewed-by: Oliver Upton <oupton@google.com>
On Wed, Sep 01, 2021 at 09:14:08PM +0000, Raghavendra Rao Ananta wrote: > 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> > --- > tools/testing/selftests/kvm/Makefile | 2 +- > .../selftests/kvm/include/aarch64/spinlock.h | 13 +++++++++ > .../selftests/kvm/lib/aarch64/spinlock.c | 27 +++++++++++++++++++ > 3 files changed, 41 insertions(+), 1 deletion(-) > create mode 100644 tools/testing/selftests/kvm/include/aarch64/spinlock.h > create mode 100644 tools/testing/selftests/kvm/lib/aarch64/spinlock.c > > diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile > index 5d05801ab816..61f0d376af99 100644 > --- a/tools/testing/selftests/kvm/Makefile > +++ b/tools/testing/selftests/kvm/Makefile > @@ -35,7 +35,7 @@ endif > > LIBKVM = lib/assert.c lib/elf.c lib/io.c lib/kvm_util.c lib/rbtree.c lib/sparsebit.c lib/test_util.c lib/guest_modes.c lib/perf_test_util.c > LIBKVM_x86_64 = lib/x86_64/apic.c lib/x86_64/processor.c lib/x86_64/vmx.c lib/x86_64/svm.c lib/x86_64/ucall.c lib/x86_64/handlers.S > -LIBKVM_aarch64 = lib/aarch64/processor.c lib/aarch64/ucall.c lib/aarch64/handlers.S > +LIBKVM_aarch64 = lib/aarch64/processor.c lib/aarch64/ucall.c lib/aarch64/handlers.S lib/aarch64/spinlock.c > LIBKVM_s390x = lib/s390x/processor.c lib/s390x/ucall.c lib/s390x/diag318_test_handler.c > > TEST_GEN_PROGS_x86_64 = x86_64/cr4_cpuid_sync_test > diff --git a/tools/testing/selftests/kvm/include/aarch64/spinlock.h b/tools/testing/selftests/kvm/include/aarch64/spinlock.h > new file mode 100644 > index 000000000000..cf0984106d14 > --- /dev/null > +++ b/tools/testing/selftests/kvm/include/aarch64/spinlock.h > @@ -0,0 +1,13 @@ > +/* SPDX-License-Identifier: GPL-2.0 */ > + > +#ifndef SELFTEST_KVM_ARM64_SPINLOCK_H > +#define SELFTEST_KVM_ARM64_SPINLOCK_H > + > +struct spinlock { > + int v; > +}; > + > +extern void spin_lock(struct spinlock *lock); > +extern void spin_unlock(struct spinlock *lock); > + > +#endif /* SELFTEST_KVM_ARM64_SPINLOCK_H */ > 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..6d66a3dac237 > --- /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) > +{ > + uint32_t 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"); > +} > -- Reviewed-by: Andrew Jones <drjones@redhat.com> It makes sense that the explicit barriers in kvm-unit-tests weren't also inherited, because we already have the implicit barriers with these ld/st instruction variants. (I suppose we could improve the kvm-unit-tests implementation at some point.) Thanks, drew
diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile index 5d05801ab816..61f0d376af99 100644 --- a/tools/testing/selftests/kvm/Makefile +++ b/tools/testing/selftests/kvm/Makefile @@ -35,7 +35,7 @@ endif LIBKVM = lib/assert.c lib/elf.c lib/io.c lib/kvm_util.c lib/rbtree.c lib/sparsebit.c lib/test_util.c lib/guest_modes.c lib/perf_test_util.c LIBKVM_x86_64 = lib/x86_64/apic.c lib/x86_64/processor.c lib/x86_64/vmx.c lib/x86_64/svm.c lib/x86_64/ucall.c lib/x86_64/handlers.S -LIBKVM_aarch64 = lib/aarch64/processor.c lib/aarch64/ucall.c lib/aarch64/handlers.S +LIBKVM_aarch64 = lib/aarch64/processor.c lib/aarch64/ucall.c lib/aarch64/handlers.S lib/aarch64/spinlock.c LIBKVM_s390x = lib/s390x/processor.c lib/s390x/ucall.c lib/s390x/diag318_test_handler.c TEST_GEN_PROGS_x86_64 = x86_64/cr4_cpuid_sync_test diff --git a/tools/testing/selftests/kvm/include/aarch64/spinlock.h b/tools/testing/selftests/kvm/include/aarch64/spinlock.h new file mode 100644 index 000000000000..cf0984106d14 --- /dev/null +++ b/tools/testing/selftests/kvm/include/aarch64/spinlock.h @@ -0,0 +1,13 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#ifndef SELFTEST_KVM_ARM64_SPINLOCK_H +#define SELFTEST_KVM_ARM64_SPINLOCK_H + +struct spinlock { + int v; +}; + +extern void spin_lock(struct spinlock *lock); +extern void spin_unlock(struct spinlock *lock); + +#endif /* SELFTEST_KVM_ARM64_SPINLOCK_H */ 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..6d66a3dac237 --- /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) +{ + uint32_t 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"); +}
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> --- tools/testing/selftests/kvm/Makefile | 2 +- .../selftests/kvm/include/aarch64/spinlock.h | 13 +++++++++ .../selftests/kvm/lib/aarch64/spinlock.c | 27 +++++++++++++++++++ 3 files changed, 41 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/kvm/include/aarch64/spinlock.h create mode 100644 tools/testing/selftests/kvm/lib/aarch64/spinlock.c