diff options
Diffstat (limited to 'Documentation')
-rw-r--r-- | Documentation/ABI/testing/sysfs-kernel-mm-hugepages | 15 | ||||
-rw-r--r-- | Documentation/vm/hugetlbpage.txt | 23 |
2 files changed, 38 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-kernel-mm-hugepages b/Documentation/ABI/testing/sysfs-kernel-mm-hugepages new file mode 100644 index 000000000000..e21c00571cf4 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-kernel-mm-hugepages | |||
@@ -0,0 +1,15 @@ | |||
1 | What: /sys/kernel/mm/hugepages/ | ||
2 | Date: June 2008 | ||
3 | Contact: Nishanth Aravamudan <nacc@us.ibm.com>, hugetlb maintainers | ||
4 | Description: | ||
5 | /sys/kernel/mm/hugepages/ contains a number of subdirectories | ||
6 | of the form hugepages-<size>kB, where <size> is the page size | ||
7 | of the hugepages supported by the kernel/CPU combination. | ||
8 | |||
9 | Under these directories are a number of files: | ||
10 | nr_hugepages | ||
11 | nr_overcommit_hugepages | ||
12 | free_hugepages | ||
13 | surplus_hugepages | ||
14 | resv_hugepages | ||
15 | See Documentation/vm/hugetlbpage.txt for details. | ||
diff --git a/Documentation/vm/hugetlbpage.txt b/Documentation/vm/hugetlbpage.txt index 3102b81bef88..8a5b5763f0fe 100644 --- a/Documentation/vm/hugetlbpage.txt +++ b/Documentation/vm/hugetlbpage.txt | |||
@@ -95,6 +95,29 @@ this condition holds, however, no more surplus huge pages will be | |||
95 | allowed on the system until one of the two sysctls are increased | 95 | allowed on the system until one of the two sysctls are increased |
96 | sufficiently, or the surplus huge pages go out of use and are freed. | 96 | sufficiently, or the surplus huge pages go out of use and are freed. |
97 | 97 | ||
98 | With support for multiple hugepage pools at run-time available, much of | ||
99 | the hugepage userspace interface has been duplicated in sysfs. The above | ||
100 | information applies to the default hugepage size (which will be | ||
101 | controlled by the proc interfaces for backwards compatibility). The root | ||
102 | hugepage control directory is | ||
103 | |||
104 | /sys/kernel/mm/hugepages | ||
105 | |||
106 | For each hugepage size supported by the running kernel, a subdirectory | ||
107 | will exist, of the form | ||
108 | |||
109 | hugepages-${size}kB | ||
110 | |||
111 | Inside each of these directories, the same set of files will exist: | ||
112 | |||
113 | nr_hugepages | ||
114 | nr_overcommit_hugepages | ||
115 | free_hugepages | ||
116 | resv_hugepages | ||
117 | surplus_hugepages | ||
118 | |||
119 | which function as described above for the default hugepage-sized case. | ||
120 | |||
98 | If the user applications are going to request hugepages using mmap system | 121 | If the user applications are going to request hugepages using mmap system |
99 | call, then it is required that system administrator mount a file system of | 122 | call, then it is required that system administrator mount a file system of |
100 | type hugetlbfs: | 123 | type hugetlbfs: |