diff mbox series

[RFC,v5,02/10] tools headers: Add a macro to get HUGETLB page sizes for mmap

Message ID 20210323135231.24948-3-wangyanan55@huawei.com
State New
Headers show
Series KVM: selftests: some improvement and a new test for kvm page table | expand

Commit Message

Yanan Wang March 23, 2021, 1:52 p.m. UTC
We know that if a system supports multiple hugetlb page sizes,
the desired hugetlb page size can be specified in bits [26:31]
of the flag arguments. The value in these 6 bits will be the
shift of each hugetlb page size.

So add a macro to get the page size shift and then calculate the
corresponding hugetlb page size, using flag x.

Cc: Ben Gardon <bgardon@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Suggested-by: Ben Gardon <bgardon@google.com>
Signed-off-by: Yanan Wang <wangyanan55@huawei.com>
Reviewed-by: Ben Gardon <bgardon@google.com>
---
 include/uapi/linux/mman.h       | 2 ++
 tools/include/uapi/linux/mman.h | 2 ++
 2 files changed, 4 insertions(+)

Comments

Yanan Wang March 24, 2021, 1:48 a.m. UTC | #1
On 2021/3/23 22:03, Andrew Jones wrote:
> $SUBJECT says "tools headers", but this is actually changing

> a UAPI header and then copying the change to tools.

Indeed. I think head of the subject should be "mm/hugetlb".
I will fix it.

Thanks,
Yanan
> Thanks,

> drew

>

> On Tue, Mar 23, 2021 at 09:52:23PM +0800, Yanan Wang wrote:

>> We know that if a system supports multiple hugetlb page sizes,

>> the desired hugetlb page size can be specified in bits [26:31]

>> of the flag arguments. The value in these 6 bits will be the

>> shift of each hugetlb page size.

>>

>> So add a macro to get the page size shift and then calculate the

>> corresponding hugetlb page size, using flag x.

>>

>> Cc: Ben Gardon <bgardon@google.com>

>> Cc: Ingo Molnar <mingo@kernel.org>

>> Cc: Adrian Hunter <adrian.hunter@intel.com>

>> Cc: Jiri Olsa <jolsa@redhat.com>

>> Cc: Arnaldo Carvalho de Melo <acme@redhat.com>

>> Cc: Arnd Bergmann <arnd@arndb.de>

>> Cc: Michael Kerrisk <mtk.manpages@gmail.com>

>> Cc: Thomas Gleixner <tglx@linutronix.de>

>> Suggested-by: Ben Gardon <bgardon@google.com>

>> Signed-off-by: Yanan Wang <wangyanan55@huawei.com>

>> Reviewed-by: Ben Gardon <bgardon@google.com>

>> ---

>>   include/uapi/linux/mman.h       | 2 ++

>>   tools/include/uapi/linux/mman.h | 2 ++

>>   2 files changed, 4 insertions(+)

>>

>> diff --git a/include/uapi/linux/mman.h b/include/uapi/linux/mman.h

>> index f55bc680b5b0..d72df73b182d 100644

>> --- a/include/uapi/linux/mman.h

>> +++ b/include/uapi/linux/mman.h

>> @@ -41,4 +41,6 @@

>>   #define MAP_HUGE_2GB	HUGETLB_FLAG_ENCODE_2GB

>>   #define MAP_HUGE_16GB	HUGETLB_FLAG_ENCODE_16GB

>>   

>> +#define MAP_HUGE_PAGE_SIZE(x) (1ULL << ((x >> MAP_HUGE_SHIFT) & MAP_HUGE_MASK))

>> +

>>   #endif /* _UAPI_LINUX_MMAN_H */

>> diff --git a/tools/include/uapi/linux/mman.h b/tools/include/uapi/linux/mman.h

>> index f55bc680b5b0..d72df73b182d 100644

>> --- a/tools/include/uapi/linux/mman.h

>> +++ b/tools/include/uapi/linux/mman.h

>> @@ -41,4 +41,6 @@

>>   #define MAP_HUGE_2GB	HUGETLB_FLAG_ENCODE_2GB

>>   #define MAP_HUGE_16GB	HUGETLB_FLAG_ENCODE_16GB

>>   

>> +#define MAP_HUGE_PAGE_SIZE(x) (1ULL << ((x >> MAP_HUGE_SHIFT) & MAP_HUGE_MASK))

>> +

>>   #endif /* _UAPI_LINUX_MMAN_H */

>> -- 

>> 2.19.1

>>

> .
diff mbox series

Patch

diff --git a/include/uapi/linux/mman.h b/include/uapi/linux/mman.h
index f55bc680b5b0..d72df73b182d 100644
--- a/include/uapi/linux/mman.h
+++ b/include/uapi/linux/mman.h
@@ -41,4 +41,6 @@ 
 #define MAP_HUGE_2GB	HUGETLB_FLAG_ENCODE_2GB
 #define MAP_HUGE_16GB	HUGETLB_FLAG_ENCODE_16GB
 
+#define MAP_HUGE_PAGE_SIZE(x) (1ULL << ((x >> MAP_HUGE_SHIFT) & MAP_HUGE_MASK))
+
 #endif /* _UAPI_LINUX_MMAN_H */
diff --git a/tools/include/uapi/linux/mman.h b/tools/include/uapi/linux/mman.h
index f55bc680b5b0..d72df73b182d 100644
--- a/tools/include/uapi/linux/mman.h
+++ b/tools/include/uapi/linux/mman.h
@@ -41,4 +41,6 @@ 
 #define MAP_HUGE_2GB	HUGETLB_FLAG_ENCODE_2GB
 #define MAP_HUGE_16GB	HUGETLB_FLAG_ENCODE_16GB
 
+#define MAP_HUGE_PAGE_SIZE(x) (1ULL << ((x >> MAP_HUGE_SHIFT) & MAP_HUGE_MASK))
+
 #endif /* _UAPI_LINUX_MMAN_H */