lkml.org 
[lkml]   [2021]   [Mar]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [RFC PATCH v4 6/9] KVM: selftests: Add a helper to get system default hugetlb page size
From
Date

On 2021/3/12 19:40, Andrew Jones wrote:
> On Tue, Mar 02, 2021 at 08:57:48PM +0800, Yanan Wang wrote:
>> If HUGETLB is configured in the host kernel, then we can know the system
>> default hugetlb page size through *cat /proc/meminfo*. Otherwise, we will
>> not see the information of hugetlb pages in file /proc/meminfo if it's not
>> configured. So add a helper to determine whether HUGETLB is configured and
>> then get the default page size by reading /proc/meminfo.
>>
>> This helper can be useful when a program wants to use the default hugetlb
>> pages of the system and doesn't know the default page size.
>>
>> Signed-off-by: Yanan Wang <wangyanan55@huawei.com>
>> ---
>> .../testing/selftests/kvm/include/test_util.h | 1 +
>> tools/testing/selftests/kvm/lib/test_util.c | 27 +++++++++++++++++++
>> 2 files changed, 28 insertions(+)
>>
>> diff --git a/tools/testing/selftests/kvm/include/test_util.h b/tools/testing/selftests/kvm/include/test_util.h
>> index ef24c76ba89a..e087174eefe5 100644
>> --- a/tools/testing/selftests/kvm/include/test_util.h
>> +++ b/tools/testing/selftests/kvm/include/test_util.h
>> @@ -80,6 +80,7 @@ struct vm_mem_backing_src_alias {
>>
>> bool thp_configured(void);
>> size_t get_trans_hugepagesz(void);
>> +size_t get_def_hugetlb_pagesz(void);
>> 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/test_util.c b/tools/testing/selftests/kvm/lib/test_util.c
>> index f2d133f76c67..80d68dbd72d2 100644
>> --- a/tools/testing/selftests/kvm/lib/test_util.c
>> +++ b/tools/testing/selftests/kvm/lib/test_util.c
>> @@ -153,6 +153,33 @@ size_t get_trans_hugepagesz(void)
>> return size;
>> }
>>
>> +size_t get_def_hugetlb_pagesz(void)
>> +{
>> + char buf[64];
>> + const char *tag = "Hugepagesize:";
>> + FILE *f;
>> +
>> + f = fopen("/proc/meminfo", "r");
>> + TEST_ASSERT(f != NULL, "Error in opening /proc/meminfo: %d", errno);
>> +
>> + while (fgets(buf, sizeof(buf), f) != NULL) {
>> + if (strstr(buf, tag) == buf) {
>> + fclose(f);
>> + return strtoull(buf + strlen(tag), NULL, 10) << 10;
>> + }
>> + }
>> +
>> + if (feof(f)) {
>> + fclose(f);
>> + TEST_FAIL("HUGETLB is not configured in host kernel");
>> + } else {
>> + fclose(f);
>> + TEST_FAIL("Error in reading /proc/meminfo: %d", errno);
>> + }
> fclose() can be factored out.
>
>> +
>> + return 0;
>> +}
>> +
>> void backing_src_help(void)
>> {
>> int i;
>> --
>> 2.23.0
>>
> Besides the fclose comment and the same errno comment as the previous
> patch
I will fix it and add your R-b in this patch.

Thanks,
Yanan
> Reviewed-by: Andrew Jones <drjones@redhat.com>
>
> .

\
 
 \ /
  Last update: 2021-03-22 07:47    [W:4.010 / U:0.012 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site