Re: [RFC PATCH v4 7/9] KVM: selftests: List all hugetlb src types specified with page sizes

["wangyanan (Y)" <wangyanan55@huawei.com>]

On 2021/3/12 20:02, Andrew Jones wrote:
> On Tue, Mar 02, 2021 at 08:57:49PM +0800, Yanan Wang wrote:
>> With VM_MEM_SRC_ANONYMOUS_HUGETLB, we currently can only use system
>> default hugetlb pages to back the testing guest memory. In order to
>> add flexibility, now list all the known hugetlb backing src types with
>> different page sizes, so that we can specify use of hugetlb pages of the
>> exact granularity that we want. And as all the known hugetlb page sizes
>> are listed, it's appropriate for all architectures.
>>
>> Besides, the helper get_backing_src_pagesz() is added to get the
>> granularity of different backing src types(anonumous, thp, hugetlb).
>>
>> Suggested-by: Ben Gardon <bgardon@google.com>
>> Signed-off-by: Yanan Wang <wangyanan55@huawei.com>
>> ---
>>   .../testing/selftests/kvm/include/test_util.h | 18 +++++-
>>   tools/testing/selftests/kvm/lib/kvm_util.c    |  2 +-
>>   tools/testing/selftests/kvm/lib/test_util.c   | 59 +++++++++++++++----
>>   3 files changed, 66 insertions(+), 13 deletions(-)
>>
>> diff --git a/tools/testing/selftests/kvm/include/test_util.h b/tools/testing/selftests/kvm/include/test_util.h
>> index e087174eefe5..fade3130eb01 100644
>> --- a/tools/testing/selftests/kvm/include/test_util.h
>> +++ b/tools/testing/selftests/kvm/include/test_util.h
>> @@ -71,16 +71,32 @@ enum vm_mem_backing_src_type {
>>   	VM_MEM_SRC_ANONYMOUS,
>>   	VM_MEM_SRC_ANONYMOUS_THP,
>>   	VM_MEM_SRC_ANONYMOUS_HUGETLB,
>> +	VM_MEM_SRC_ANONYMOUS_HUGETLB_16KB,
>> +	VM_MEM_SRC_ANONYMOUS_HUGETLB_64KB,
>> +	VM_MEM_SRC_ANONYMOUS_HUGETLB_512KB,
>> +	VM_MEM_SRC_ANONYMOUS_HUGETLB_1MB,
>> +	VM_MEM_SRC_ANONYMOUS_HUGETLB_2MB,
>> +	VM_MEM_SRC_ANONYMOUS_HUGETLB_8MB,
>> +	VM_MEM_SRC_ANONYMOUS_HUGETLB_16MB,
>> +	VM_MEM_SRC_ANONYMOUS_HUGETLB_32MB,
>> +	VM_MEM_SRC_ANONYMOUS_HUGETLB_256MB,
>> +	VM_MEM_SRC_ANONYMOUS_HUGETLB_512MB,
>> +	VM_MEM_SRC_ANONYMOUS_HUGETLB_1GB,
>> +	VM_MEM_SRC_ANONYMOUS_HUGETLB_2GB,
>> +	VM_MEM_SRC_ANONYMOUS_HUGETLB_16GB,
>> +	NUM_SRC_TYPES,
>>   };
>>   
>>   struct vm_mem_backing_src_alias {
>>   	const char *name;
>> -	enum vm_mem_backing_src_type type;
>> +	uint32_t flag;
>>   };
>>   
>>   bool thp_configured(void);
>>   size_t get_trans_hugepagesz(void);
>>   size_t get_def_hugetlb_pagesz(void);
>> +const struct vm_mem_backing_src_alias *vm_mem_backing_src_alias(uint32_t i);
>> +size_t get_backing_src_pagesz(uint32_t i);
>>   void backing_src_help(void);
>>   enum vm_mem_backing_src_type parse_backing_src_type(const char *type_name);
>>   
>> diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
>> index cc22c4ab7d67..b91c8e3a7ee1 100644
>> --- a/tools/testing/selftests/kvm/lib/kvm_util.c
>> +++ b/tools/testing/selftests/kvm/lib/kvm_util.c
>> @@ -757,7 +757,7 @@ void vm_userspace_mem_region_add(struct kvm_vm *vm,
>>   	region->mmap_start = mmap(NULL, region->mmap_size,
>>   				  PROT_READ | PROT_WRITE,
>>   				  MAP_PRIVATE | MAP_ANONYMOUS
>> -				  | (src_type == VM_MEM_SRC_ANONYMOUS_HUGETLB ? MAP_HUGETLB : 0),
>> +				  | vm_mem_backing_src_alias(src_type)->flag,
>>   				  -1, 0);
>>   	TEST_ASSERT(region->mmap_start != MAP_FAILED,
>>   		    "test_malloc failed, mmap_start: %p errno: %i",
>> diff --git a/tools/testing/selftests/kvm/lib/test_util.c b/tools/testing/selftests/kvm/lib/test_util.c
>> index 80d68dbd72d2..df8a42eff1f8 100644
>> --- a/tools/testing/selftests/kvm/lib/test_util.c
>> +++ b/tools/testing/selftests/kvm/lib/test_util.c
>> @@ -11,6 +11,7 @@
>>   #include <stdlib.h>
>>   #include <time.h>
>>   #include <sys/stat.h>
>> +#include <linux/mman.h>
>>   #include "linux/kernel.h"
>>   
>>   #include "test_util.h"
>> @@ -112,12 +113,6 @@ void print_skip(const char *fmt, ...)
>>   	puts(", skipping test");
>>   }
>>   
>> -const struct vm_mem_backing_src_alias backing_src_aliases[] = {
>> -	{"anonymous", VM_MEM_SRC_ANONYMOUS,},
>> -	{"anonymous_thp", VM_MEM_SRC_ANONYMOUS_THP,},
>> -	{"anonymous_hugetlb", VM_MEM_SRC_ANONYMOUS_HUGETLB,},
>> -};
>> -
>>   bool thp_configured(void)
>>   {
>>   	int ret;
>> @@ -180,22 +175,64 @@ size_t get_def_hugetlb_pagesz(void)
>>   	return 0;
>>   }
>>   
>> +const struct vm_mem_backing_src_alias *vm_mem_backing_src_alias(uint32_t i)
>> +{
>> +	static const struct vm_mem_backing_src_alias aliases[] = {
>> +		{ "anonymous",               0                            },
>> +		{ "anonymous_thp",           0                            },
>> +		{ "anonymous_hugetlb",       MAP_HUGETLB                  },
>> +		{ "anonymous_hugetlb_16kb",  MAP_HUGETLB | MAP_HUGE_16KB  },
>> +		{ "anonymous_hugetlb_64kb",  MAP_HUGETLB | MAP_HUGE_64KB  },
>> +		{ "anonymous_hugetlb_512kb", MAP_HUGETLB | MAP_HUGE_512KB },
>> +		{ "anonymous_hugetlb_1mb",   MAP_HUGETLB | MAP_HUGE_1MB   },
>> +		{ "anonymous_hugetlb_2mb",   MAP_HUGETLB | MAP_HUGE_2MB   },
>> +		{ "anonymous_hugetlb_8mb",   MAP_HUGETLB | MAP_HUGE_8MB   },
>> +		{ "anonymous_hugetlb_16mb",  MAP_HUGETLB | MAP_HUGE_16MB  },
>> +		{ "anonymous_hugetlb_32mb",  MAP_HUGETLB | MAP_HUGE_32MB  },
>> +		{ "anonymous_hugetlb_256mb", MAP_HUGETLB | MAP_HUGE_256MB },
>> +		{ "anonymous_hugetlb_512mb", MAP_HUGETLB | MAP_HUGE_512MB },
>> +		{ "anonymous_hugetlb_1gb",   MAP_HUGETLB | MAP_HUGE_1GB   },
>> +		{ "anonymous_hugetlb_2gb",   MAP_HUGETLB | MAP_HUGE_2GB   },
>> +		{ "anonymous_hugetlb_16gb",  MAP_HUGETLB | MAP_HUGE_16GB  },
>> +	};
>> +	_Static_assert(ARRAY_SIZE(aliases) == NUM_SRC_TYPES,
>> +		       "Missing new backing src types?");
>> +
>> +	TEST_ASSERT(i < NUM_SRC_TYPES, "Backing src type ID %d too big", i);
>> +
>> +	return &aliases[i];
>> +}
>> +
>> +size_t get_backing_src_pagesz(uint32_t i)
>> +{
>> +	uint32_t flag = vm_mem_backing_src_alias(i)->flag;
>> +
>> +	if (i == VM_MEM_SRC_ANONYMOUS)
>> +		return getpagesize();
>> +	if (i == VM_MEM_SRC_ANONYMOUS_THP)
>> +		return get_trans_hugepagesz();
>> +	if (i == VM_MEM_SRC_ANONYMOUS_HUGETLB)
>> +		return get_def_hugetlb_pagesz();
>> +
>> +	return MAP_HUGE_PAGE_SIZE(flag);
>> +}
>> +
>>   void backing_src_help(void)
>>   {
>>   	int i;
>>   
>>   	printf("Available backing src types:\n");
>> -	for (i = 0; i < ARRAY_SIZE(backing_src_aliases); i++)
>> -		printf("\t%s\n", backing_src_aliases[i].name);
>> +		for (i = 0; i < NUM_SRC_TYPES; i++)
>> +			printf("\t%s\n", vm_mem_backing_src_alias(i)->name);
>>   }
>>   
>>   enum vm_mem_backing_src_type parse_backing_src_type(const char *type_name)
>>   {
>>   	int i;
>>   
>> -	for (i = 0; i < ARRAY_SIZE(backing_src_aliases); i++)
>> -		if (!strcmp(type_name, backing_src_aliases[i].name))
>> -			return backing_src_aliases[i].type;
>> +	for (i = 0; i < NUM_SRC_TYPES; i++)
>> +		if (!strcmp(type_name, vm_mem_backing_src_alias(i)->name))
>> +			return i;
> This requires vm_mem_backing_src_alias.aliases[] to be in the same order
> as vm_mem_backing_src_type, so we should do the designated array
> initialization like in vm_guest_mode_string().
That's right!

Thanks,
Yanan
> Thanks,
> drew
>
>>   
>>   	backing_src_help();
>>   	TEST_FAIL("Unknown backing src type: %s", type_name);
>> -- 
>> 2.23.0
>>
> .