[PATCH v7 01/11] KVM: selftests: Remove dynamic memory allocation for stats header

Ben Gardon
2022-05-03T18:30:57Z

There's no need to allocate dynamic memory for the stats header since
its size is known at compile time.

Reviewed-by: David Matlack <dmatlack@google.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Ben Gardon <bgardon@google.com>
---
.../selftests/kvm/kvm_binary_stats_test.c | 58 +++++++++----------
1 file changed, 27 insertions(+), 31 deletions(-)

diff --git a/tools/testing/selftests/kvm/kvm_binary_stats_test.c b/tools/testing/selftests/kvm/kvm_binary_stats_test.c
index 17f65d514915..dad34d8a41fe 100644
--- a/tools/testing/selftests/kvm/kvm_binary_stats_test.c
+++ b/tools/testing/selftests/kvm/kvm_binary_stats_test.c
@@ -26,56 +26,53 @@ static void stats_test(int stats_fd)
int i;
size_t size_desc;
size_t size_data = 0;
- struct kvm_stats_header *header;
+ struct kvm_stats_header header;
char *id;
struct kvm_stats_desc *stats_desc;
u64 *stats_data;
struct kvm_stats_desc *pdesc;

/* Read kvm stats header */
- header = malloc(sizeof(*header));
- TEST_ASSERT(header, "Allocate memory for stats header");
-
- ret = read(stats_fd, header, sizeof(*header));
- TEST_ASSERT(ret == sizeof(*header), "Read stats header");
- size_desc = sizeof(*stats_desc) + header->name_size;
+ ret = read(stats_fd, &header, sizeof(header));
+ TEST_ASSERT(ret == sizeof(header), "Read stats header");
+ size_desc = sizeof(*stats_desc) + header.name_size;

/* Read kvm stats id string */
- id = malloc(header->name_size);
+ id = malloc(header.name_size);
TEST_ASSERT(id, "Allocate memory for id string");
- ret = read(stats_fd, id, header->name_size);
- TEST_ASSERT(ret == header->name_size, "Read id string");
+ ret = read(stats_fd, id, header.name_size);
+ TEST_ASSERT(ret == header.name_size, "Read id string");

/* Check id string, that should start with "kvm" */
- TEST_ASSERT(!strncmp(id, "kvm", 3) && strlen(id) < header->name_size,
+ TEST_ASSERT(!strncmp(id, "kvm", 3) && strlen(id) < header.name_size,
"Invalid KVM stats type, id: %s", id);

/* Sanity check for other fields in header */
- if (header->num_desc == 0) {
+ if (header.num_desc == 0) {
printf("No KVM stats defined!");
return;
}
/* Check overlap */
- TEST_ASSERT(header->desc_offset > 0 && header->data_offset > 0
- && header->desc_offset >= sizeof(*header)
- && header->data_offset >= sizeof(*header),
+ TEST_ASSERT(header.desc_offset > 0 && header.data_offset > 0
+ && header.desc_offset >= sizeof(header)
+ && header.data_offset >= sizeof(header),
"Invalid offset fields in header");
- TEST_ASSERT(header->desc_offset > header->data_offset ||
- (header->desc_offset + size_desc * header->num_desc <=
- header->data_offset),
+ TEST_ASSERT(header.desc_offset > header.data_offset ||
+ (header.desc_offset + size_desc * header.num_desc <=
+ header.data_offset),
"Descriptor block is overlapped with data block");

/* Allocate memory for stats descriptors */
- stats_desc = calloc(header->num_desc, size_desc);
+ 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,
+ size_desc * header.num_desc, header.desc_offset);
+ TEST_ASSERT(ret == size_desc * header.num_desc,
"Read KVM stats descriptors");

/* Sanity check for fields in descriptors */
- for (i = 0; i < header->num_desc; ++i) {
+ for (i = 0; i < header.num_desc; ++i) {
pdesc = (void *)stats_desc + i * size_desc;
/* Check type,unit,base boundaries */
TEST_ASSERT((pdesc->flags & KVM_STATS_TYPE_MASK)
@@ -104,7 +101,7 @@ static void stats_test(int stats_fd)
break;
}
/* Check name string */
- TEST_ASSERT(strlen(pdesc->name) < header->name_size,
+ TEST_ASSERT(strlen(pdesc->name) < header.name_size,
"KVM stats name(%s) too long", pdesc->name);
/* Check size field, which should not be zero */
TEST_ASSERT(pdesc->size, "KVM descriptor(%s) with size of 0",
@@ -124,14 +121,14 @@ static void stats_test(int stats_fd)
size_data += pdesc->size * sizeof(*stats_data);
}
/* Check overlap */
- TEST_ASSERT(header->data_offset >= header->desc_offset
- || header->data_offset + size_data <= header->desc_offset,
+ TEST_ASSERT(header.data_offset >= header.desc_offset
+ || header.data_offset + size_data <= header.desc_offset,
"Data block is overlapped with Descriptor block");
/* Check validity of all stats data size */
- TEST_ASSERT(size_data >= header->num_desc * sizeof(*stats_data),
+ TEST_ASSERT(size_data >= header.num_desc * sizeof(*stats_data),
"Data size is not correct");
/* Check stats offset */
- for (i = 0; i < header->num_desc; ++i) {
+ for (i = 0; i < header.num_desc; ++i) {
pdesc = (void *)stats_desc + i * size_desc;
TEST_ASSERT(pdesc->offset < size_data,
"Invalid offset (%u) for stats: %s",
@@ -142,15 +139,15 @@ static void stats_test(int stats_fd)
stats_data = malloc(size_data);
TEST_ASSERT(stats_data, "Allocate memory for stats data");
/* Read kvm stats data as a bulk */
- ret = pread(stats_fd, stats_data, size_data, header->data_offset);
+ 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) {
+ 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);
+ 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);
@@ -159,7 +156,6 @@ static void stats_test(int stats_fd)
free(stats_data);
free(stats_desc);
free(id);
- free(header);
}

--
2.36.0.464.gb9c8b46e94-goog