Move the code to read the binary stats descriptors to the KVM selftests library. It will be re-used by other tests to check KVM behavior. No functional change intended. Reviewed-by: David Matlack <dmatlack@xxxxxxxxxx> Reviewed-by: Peter Xu <peterx@xxxxxxxxxx> Signed-off-by: Ben Gardon <bgardon@xxxxxxxxxx> --- .../selftests/kvm/include/kvm_util_base.h | 25 ++++++++++++++ .../selftests/kvm/kvm_binary_stats_test.c | 16 +++------ tools/testing/selftests/kvm/lib/kvm_util.c | 33 +++++++++++++++++++ 3 files changed, 63 insertions(+), 11 deletions(-) diff --git a/tools/testing/selftests/kvm/include/kvm_util_base.h b/tools/testing/selftests/kvm/include/kvm_util_base.h index 3d3dd144f427..6c66c6ef485b 100644 --- a/tools/testing/selftests/kvm/include/kvm_util_base.h +++ b/tools/testing/selftests/kvm/include/kvm_util_base.h @@ -311,6 +311,31 @@ static inline void read_stats_header(int stats_fd, struct kvm_stats_header *head TEST_ASSERT(ret == sizeof(*header), "Read stats header"); } +struct kvm_stats_desc *read_stats_descriptors(int stats_fd, + struct kvm_stats_header *header); + +static inline ssize_t get_stats_descriptor_size(struct kvm_stats_header *header) +{ + /* + * The base size of the descriptor is defined by KVM's ABI, but the + * size of the name field is variable, as far as KVM's ABI is + * concerned. For a given instance of KVM, the name field is the same + * size for all stats and is provided in the overall stats header. + */ + return sizeof(struct kvm_stats_desc) + header->name_size; +} + +static inline struct kvm_stats_desc *get_stats_descriptor(struct kvm_stats_desc *stats, + int index, + struct kvm_stats_header *header) +{ + /* + * Note, size_desc includes the size of the name field, which is + * variable. i.e. this is NOT equivalent to &stats_desc[i]. + */ + return (void *)stats + index * get_stats_descriptor_size(header); +} + void vm_create_irqchip(struct kvm_vm *vm); void vm_set_user_memory_region(struct kvm_vm *vm, uint32_t slot, uint32_t flags, diff --git a/tools/testing/selftests/kvm/kvm_binary_stats_test.c b/tools/testing/selftests/kvm/kvm_binary_stats_test.c index 64db17faacd2..9d3b9a0ce2ef 100644 --- a/tools/testing/selftests/kvm/kvm_binary_stats_test.c +++ b/tools/testing/selftests/kvm/kvm_binary_stats_test.c @@ -35,7 +35,7 @@ static void stats_test(int stats_fd) /* Read kvm stats header */ read_stats_header(stats_fd, &header); - size_desc = sizeof(*stats_desc) + header.name_size; + size_desc = get_stats_descriptor_size(&header); /* Read kvm stats id string */ id = malloc(header.name_size); @@ -62,18 +62,12 @@ static void stats_test(int stats_fd) header.data_offset), "Descriptor block is overlapped with data block"); - /* Allocate memory for stats descriptors */ - stats_desc = calloc(header.num_desc, size_desc); - TEST_ASSERT(stats_desc, "Allocate memory for stats descriptors"); /* Read kvm stats descriptors */ - ret = pread(stats_fd, stats_desc, - size_desc * header.num_desc, header.desc_offset); - TEST_ASSERT(ret == size_desc * header.num_desc, - "Read KVM stats descriptors"); + stats_desc = read_stats_descriptors(stats_fd, &header); /* Sanity check for fields in descriptors */ for (i = 0; i < header.num_desc; ++i) { - pdesc = (void *)stats_desc + i * size_desc; + pdesc = get_stats_descriptor(stats_desc, i, &header); /* Check type,unit,base boundaries */ TEST_ASSERT((pdesc->flags & KVM_STATS_TYPE_MASK) <= KVM_STATS_TYPE_MAX, "Unknown KVM stats type"); @@ -129,7 +123,7 @@ static void stats_test(int stats_fd) "Data size is not correct"); /* Check stats offset */ for (i = 0; i < header.num_desc; ++i) { - pdesc = (void *)stats_desc + i * size_desc; + pdesc = get_stats_descriptor(stats_desc, i, &header); TEST_ASSERT(pdesc->offset < size_data, "Invalid offset (%u) for stats: %s", pdesc->offset, pdesc->name); @@ -144,7 +138,7 @@ static void stats_test(int stats_fd) /* Read kvm stats data one by one */ size_data = 0; for (i = 0; i < header.num_desc; ++i) { - pdesc = (void *)stats_desc + i * size_desc; + pdesc = get_stats_descriptor(stats_desc, i, &header); ret = pread(stats_fd, stats_data, pdesc->size * sizeof(*stats_data), header.data_offset + size_data); diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c index 39f2f5f1338f..fc957a385a0a 100644 --- a/tools/testing/selftests/kvm/lib/kvm_util.c +++ b/tools/testing/selftests/kvm/lib/kvm_util.c @@ -1857,3 +1857,36 @@ unsigned int vm_calc_num_guest_pages(enum vm_guest_mode mode, size_t size) n = DIV_ROUND_UP(size, vm_guest_mode_params[mode].page_size); return vm_adjust_num_guest_pages(mode, n); } + +/* + * Read binary stats descriptors + * + * 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 + * + * Output Args: None + * + * Return: + * A pointer to a newly allocated series of stat descriptors. + * Caller is responsible for freeing the returned kvm_stats_desc. + * + * Read the stats descriptors from the binary stats interface. + */ +struct kvm_stats_desc *read_stats_descriptors(int stats_fd, + struct kvm_stats_header *header) +{ + struct kvm_stats_desc *stats_desc; + ssize_t desc_size, total_size, ret; + + desc_size = get_stats_descriptor_size(header); + total_size = header->num_desc * desc_size; + + stats_desc = calloc(header->num_desc, desc_size); + TEST_ASSERT(stats_desc, "Allocate memory for stats descriptors"); + + ret = pread(stats_fd, stats_desc, total_size, header->desc_offset); + TEST_ASSERT(ret == total_size, "Read KVM stats descriptors"); + + return stats_desc; +} -- 2.36.1.476.g0c4daa206d-goog