On Wed, Jun 24, 2015 at 08:12:52PM +0100, Peter Maydell wrote: > On 24 June 2015 at 18:18, Alex Bennée <alex.ben...@linaro.org> wrote: > > > > Paolo Bonzini <pbonz...@redhat.com> writes: > > > >> On 24/06/2015 17:34, Alex Bennée wrote: > >>> Testing with Alexander's bare metal syncronisation tests fails in MTTCG > >>> leaving one CPU spinning forever waiting for the second CPU to wake up. > >>> We simply need to poke the halt_cond once we have processed the PSCI > >>> power on call. > >>> > >>> Tested-by: Alex Bennée <alex.ben...@linaro.org> > >>> CC: Alexander Spyridakis <a.spyrida...@virtualopensystems.com> > >>> > >>> --- > >>> TODO > >>> - exactly how does the vexpress wake up it's sleeping CPUs? > >>> --- > >>> target-arm/psci.c | 2 ++ > >>> 1 file changed, 2 insertions(+) > >>> > >>> diff --git a/target-arm/psci.c b/target-arm/psci.c > >>> index d8fafab..661ff28 100644 > >>> --- a/target-arm/psci.c > >>> +++ b/target-arm/psci.c > >>> @@ -196,6 +196,8 @@ void arm_handle_psci_call(ARMCPU *cpu) > >>> } > >>> target_cpu_class->set_pc(target_cpu_state, entry); > >>> > >>> + qemu_cond_signal(target_cpu_state->halt_cond); > >> > >> That's called qemu_cpu_kick(target_cpu_state). :) The patch should be > >> acceptable now upstream, I think. > > > > Oh so this might well fail in KVM too? > > In KVM we won't use target-arm/psci.c because PSCI calls > are handled in the kernel. >
It's also not valid to use Alexander's test on KVM, as the test framework doesn't enable the mmu, and thus {ldr,str}ex won't work as expected. I guess I need to do a better job at advertising/documenting kvm-unit-tests/arm, as that framework would suit this test just fine. I've attached a patch porting the test over to k-u-t[1]. After applying the patch, do ./configure --arch=arm64 --cross-prefix=aarch64-linux-gnu- OR ./configure --arch=arm --cross-prefix=arm-linux-gnu- make arm/run arm/vos-spinlock-test.flat -smp 4 # non-atomic locks OR arm/run arm/vos-spinlock-test.flat -smp 4 -append atomic # atomic locks Thanks, drew [1] git://git.kernel.org/pub/scm/virt/kvm/kvm-unit-tests.git
>From dea26966a92cc65f23c0ac7bf2620982e0a9c57d Mon Sep 17 00:00:00 2001 From: Andrew Jones <drjo...@redhat.com> Date: Thu, 25 Jun 2015 17:28:53 +0200 Subject: [PATCH] arm/arm64: add spinlock torture test This is port of the test in virtualopensystems tcg_baremetal_tests. Signed-off-by: Andrew Jones <drjo...@redhat.com> --- arm/vos-spinlock-test.c | 92 ++++++++++++++++++++++++++++++++++++++++++++ config/config-arm-common.mak | 4 +- 2 files changed, 95 insertions(+), 1 deletion(-) create mode 100644 arm/vos-spinlock-test.c diff --git a/arm/vos-spinlock-test.c b/arm/vos-spinlock-test.c new file mode 100644 index 0000000000000..6cc62c6f49dfb --- /dev/null +++ b/arm/vos-spinlock-test.c @@ -0,0 +1,92 @@ +#include <libcflat.h> +#include <asm/smp.h> +#include <asm/cpumask.h> +#include <asm/barrier.h> + +#define LOOP_SIZE 10000000 + +struct lock_ops { + void (*lock)(int *v); + void (*unlock)(int *v); +}; +static struct lock_ops lock_ops; + +static void gcc_builtin_lock(int *lock_var) +{ + while (__sync_lock_test_and_set(lock_var, 1)); +} +static void gcc_builtin_unlock(int *lock_var) +{ + __sync_lock_release(lock_var); +} +static void none_lock(int *lock_var) +{ + while (*lock_var != 0); + *lock_var = 1; +} +static void none_unlock(int *lock_var) +{ + *lock_var = 0; +} + +static int global_a, global_b; +static int global_lock; + +static cpumask_t smp_test_complete; + +static void test_spinlock(void) +{ + int i, errors = 0; + int cpu = smp_processor_id(); + + printf("CPU%d online\n", cpu); + + for (i = 0; i < LOOP_SIZE; i++) { + + lock_ops.lock(&global_lock); + + if (global_a == (cpu + 1) % 2) { + global_a = 1; + global_b = 0; + } else { + global_a = 0; + global_b = 1; + } + + if (global_a == global_b) + errors++; + + lock_ops.unlock(&global_lock); + } + report("CPU%d: Done - Errors: %d\n", errors == 0, cpu, errors); + + cpumask_set_cpu(cpu, &smp_test_complete); + if (cpu != 0) + halt(); +} + +int main(int argc, char **argv) +{ + int cpu; + + if (argc && strcmp(argv[0], "atomic") == 0) { + lock_ops.lock = gcc_builtin_lock; + lock_ops.unlock = gcc_builtin_unlock; + } else { + lock_ops.lock = none_lock; + lock_ops.unlock = none_unlock; + } + + for_each_present_cpu(cpu) { + if (cpu == 0) + continue; + smp_boot_secondary(cpu, test_spinlock); + } + + test_spinlock(); + + while (!cpumask_full(&smp_test_complete)) + cpu_relax(); + + return report_summary(); +} diff --git a/config/config-arm-common.mak b/config/config-arm-common.mak index 314261ef60cf7..6f4c8ee163c3d 100644 --- a/config/config-arm-common.mak +++ b/config/config-arm-common.mak @@ -10,7 +10,8 @@ ifeq ($(LOADADDR),) endif tests-common = \ - $(TEST_DIR)/selftest.flat + $(TEST_DIR)/selftest.flat \ + $(TEST_DIR)/vos-spinlock-test.flat all: test_cases @@ -70,3 +71,4 @@ generated_files = $(asm-offsets) test_cases: $(generated_files) $(tests-common) $(tests) $(TEST_DIR)/selftest.elf: $(cstart.o) $(TEST_DIR)/selftest.o +$(TEST_DIR)/vos-spinlock-test.elf: $(cstart.o) $(TEST_DIR)/vos-spinlock-test.o -- 2.4.3