Message ID | 20220420173513.1217360-6-bgardon@google.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | KVM: x86: Add a cap to disable NX hugepages on a VM | expand |
On Wed, Apr 20, 2022 at 10:35:08AM -0700, Ben Gardon wrote: > Move the code to read the binary stats data to the KVM selftests > library. It will be re-used by other tests to check KVM behavior. > > No functional change intended. I think there's a very trivial functional change... > > Reviewed-by: David Matlack <dmatlack@google.com> > Signed-off-by: Ben Gardon <bgardon@google.com> > --- > .../selftests/kvm/include/kvm_util_base.h | 3 ++ > .../selftests/kvm/kvm_binary_stats_test.c | 7 ++-- > tools/testing/selftests/kvm/lib/kvm_util.c | 36 +++++++++++++++++++ > 3 files changed, 41 insertions(+), 5 deletions(-) > > diff --git a/tools/testing/selftests/kvm/include/kvm_util_base.h b/tools/testing/selftests/kvm/include/kvm_util_base.h > index fabe46ddc1b2..2a3a4d9ed8e3 100644 > --- a/tools/testing/selftests/kvm/include/kvm_util_base.h > +++ b/tools/testing/selftests/kvm/include/kvm_util_base.h > @@ -403,6 +403,9 @@ int vcpu_get_stats_fd(struct kvm_vm *vm, uint32_t vcpuid); > void read_stats_header(int stats_fd, struct kvm_stats_header *header); > struct kvm_stats_desc *read_stats_desc(int stats_fd, > struct kvm_stats_header *header); > +int read_stat_data(int stats_fd, struct kvm_stats_header *header, > + struct kvm_stats_desc *desc, uint64_t *data, > + ssize_t max_elements); > > uint32_t guest_get_vcpuid(void); > > diff --git a/tools/testing/selftests/kvm/kvm_binary_stats_test.c b/tools/testing/selftests/kvm/kvm_binary_stats_test.c > index 8b31f8fc7e08..59677fae26e5 100644 > --- a/tools/testing/selftests/kvm/kvm_binary_stats_test.c > +++ b/tools/testing/selftests/kvm/kvm_binary_stats_test.c > @@ -160,11 +160,8 @@ static void stats_test(int stats_fd) > size_data = 0; > for (i = 0; i < header.num_desc; ++i) { > pdesc = (void *)stats_desc + i * size_desc; > - ret = pread(stats_fd, stats_data, > - pdesc->size * sizeof(*stats_data), > - header.data_offset + size_data); > - TEST_ASSERT(ret == pdesc->size * sizeof(*stats_data), > - "Read data of KVM stats: %s", pdesc->name); > + read_stat_data(stats_fd, &header, pdesc, stats_data, > + pdesc->size); > size_data += pdesc->size * sizeof(*stats_data); > } > > diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c > index 12fa8cc88043..ea4ab64e5997 100644 > --- a/tools/testing/selftests/kvm/lib/kvm_util.c > +++ b/tools/testing/selftests/kvm/lib/kvm_util.c > @@ -2615,3 +2615,39 @@ struct kvm_stats_desc *read_stats_desc(int stats_fd, > > return stats_desc; > } > + > +/* > + * Read stat data for a particular stat > + * > + * Input Args: > + * stats_fd - the file descriptor for the binary stats file from which to read > + * header - the binary stats metadata header corresponding to the given FD > + * desc - the binary stat metadata for the particular stat to be read > + * max_elements - the maximum number of 8-byte values to read into data > + * > + * Output Args: > + * data - the buffer into which stat data should be read > + * > + * Return: > + * The number of data elements read into data or -ERRNO on error. > + * > + * Read the data values of a specified stat from the binary stats interface. > + */ > +int read_stat_data(int stats_fd, struct kvm_stats_header *header, > + struct kvm_stats_desc *desc, uint64_t *data, > + ssize_t max_elements) > +{ > + ssize_t size = min_t(ssize_t, desc->size, max_elements); > + ssize_t ret; > + > + ret = pread(stats_fd, data, size * sizeof(*data), > + header->data_offset + desc->offset); > + > + /* ret from pread is in bytes. */ > + ret = ret / sizeof(*data); > + > + TEST_ASSERT(ret == size, > + "Read data of KVM stats: %s", desc->name); ... where we do the check with 8-bytes aligned now, so we'll stop failing the case e.g. when pread() didn't get multiples of 8 bytes. But not a big deal I guess. Reviewed-by: Peter Xu <peterx@redhat.com> Thanks,
diff --git a/tools/testing/selftests/kvm/include/kvm_util_base.h b/tools/testing/selftests/kvm/include/kvm_util_base.h index fabe46ddc1b2..2a3a4d9ed8e3 100644 --- a/tools/testing/selftests/kvm/include/kvm_util_base.h +++ b/tools/testing/selftests/kvm/include/kvm_util_base.h @@ -403,6 +403,9 @@ int vcpu_get_stats_fd(struct kvm_vm *vm, uint32_t vcpuid); void read_stats_header(int stats_fd, struct kvm_stats_header *header); struct kvm_stats_desc *read_stats_desc(int stats_fd, struct kvm_stats_header *header); +int read_stat_data(int stats_fd, struct kvm_stats_header *header, + struct kvm_stats_desc *desc, uint64_t *data, + ssize_t max_elements); uint32_t guest_get_vcpuid(void); diff --git a/tools/testing/selftests/kvm/kvm_binary_stats_test.c b/tools/testing/selftests/kvm/kvm_binary_stats_test.c index 8b31f8fc7e08..59677fae26e5 100644 --- a/tools/testing/selftests/kvm/kvm_binary_stats_test.c +++ b/tools/testing/selftests/kvm/kvm_binary_stats_test.c @@ -160,11 +160,8 @@ static void stats_test(int stats_fd) size_data = 0; for (i = 0; i < header.num_desc; ++i) { pdesc = (void *)stats_desc + i * size_desc; - ret = pread(stats_fd, stats_data, - pdesc->size * sizeof(*stats_data), - header.data_offset + size_data); - TEST_ASSERT(ret == pdesc->size * sizeof(*stats_data), - "Read data of KVM stats: %s", pdesc->name); + read_stat_data(stats_fd, &header, pdesc, stats_data, + pdesc->size); size_data += pdesc->size * sizeof(*stats_data); } diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c index 12fa8cc88043..ea4ab64e5997 100644 --- a/tools/testing/selftests/kvm/lib/kvm_util.c +++ b/tools/testing/selftests/kvm/lib/kvm_util.c @@ -2615,3 +2615,39 @@ struct kvm_stats_desc *read_stats_desc(int stats_fd, return stats_desc; } + +/* + * Read stat data for a particular stat + * + * Input Args: + * stats_fd - the file descriptor for the binary stats file from which to read + * header - the binary stats metadata header corresponding to the given FD + * desc - the binary stat metadata for the particular stat to be read + * max_elements - the maximum number of 8-byte values to read into data + * + * Output Args: + * data - the buffer into which stat data should be read + * + * Return: + * The number of data elements read into data or -ERRNO on error. + * + * Read the data values of a specified stat from the binary stats interface. + */ +int read_stat_data(int stats_fd, struct kvm_stats_header *header, + struct kvm_stats_desc *desc, uint64_t *data, + ssize_t max_elements) +{ + ssize_t size = min_t(ssize_t, desc->size, max_elements); + ssize_t ret; + + ret = pread(stats_fd, data, size * sizeof(*data), + header->data_offset + desc->offset); + + /* ret from pread is in bytes. */ + ret = ret / sizeof(*data); + + TEST_ASSERT(ret == size, + "Read data of KVM stats: %s", desc->name); + + return ret; +}