Commit ed6b53ec authored by Ben Gardon's avatar Ben Gardon Committed by Paolo Bonzini
Browse files

KVM: selftests: Read binary stat data in lib 



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.

Also opportunistically remove an unnecessary calculation with
"size_data" in stats_test.

Reviewed-by: default avatarDavid Matlack <dmatlack@google.com>
Reviewed-by: default avatarPeter Xu <peterx@redhat.com>
Signed-off-by: default avatarBen Gardon <bgardon@google.com>
Message-Id: <20220613212523.3436117-6-bgardon@google.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 143e7eea

tools/testing/selftests/kvm/include/kvm_util_base.h

+4 −0
Original line number Diff line number Diff line
@@ -341,6 +341,10 @@ static inline struct kvm_stats_desc *get_stats_descriptor(struct kvm_stats_desc 
	return (void *)stats + index * get_stats_descriptor_size(header);

}



void read_stat_data(int stats_fd, struct kvm_stats_header *header,

		    struct kvm_stats_desc *desc, uint64_t *data,

		    size_t max_elements);



void vm_create_irqchip(struct kvm_vm *vm);



void vm_set_user_memory_region(struct kvm_vm *vm, uint32_t slot, uint32_t flags,

tools/testing/selftests/kvm/kvm_binary_stats_test.c

+2 −7
Original line number Diff line number Diff line
@@ -147,15 +147,10 @@ static void stats_test(int stats_fd) 
	ret = pread(stats_fd, stats_data, size_data, header.data_offset);

	TEST_ASSERT(ret == size_data, "Read KVM stats data");

	/* Read kvm stats data one by one */

	size_data = 0;

	for (i = 0; i < header.num_desc; ++i) {

		pdesc = get_stats_descriptor(stats_desc, i, &header);

		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);

		size_data += pdesc->size * sizeof(*stats_data);

		read_stat_data(stats_fd, &header, pdesc, stats_data,

			       pdesc->size);

	}



	free(stats_data);

tools/testing/selftests/kvm/lib/kvm_util.c

+35 −0
Original line number Diff line number Diff line
@@ -1883,3 +1883,38 @@ struct kvm_stats_desc *read_stats_descriptors(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

 *

 * Read the data values of a specified stat from the binary stats interface.

 */

void read_stat_data(int stats_fd, struct kvm_stats_header *header,

		    struct kvm_stats_desc *desc, uint64_t *data,

		    size_t max_elements)

{

	size_t nr_elements = min_t(ssize_t, desc->size, max_elements);

	size_t size = nr_elements * sizeof(*data);

	ssize_t ret;



	TEST_ASSERT(desc->size, "No elements in stat '%s'", desc->name);

	TEST_ASSERT(max_elements, "Zero elements requested for stat '%s'", desc->name);



	ret = pread(stats_fd, data, size,

		    header->data_offset + desc->offset);



	TEST_ASSERT(ret >= 0, "pread() failed on stat '%s', errno: %i (%s)",

		    desc->name, errno, strerror(errno));

	TEST_ASSERT(ret == size,

		    "pread() on stat '%s' read %ld bytes, wanted %lu bytes",

		    desc->name, size, ret);

}