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author | Nishanth Aravamudan <nacc@us.ibm.com> | 2008-07-23 21:27:44 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2008-07-24 10:47:17 -0700 |
commit | a3437870160cf2caaac6bdd76c7377a5a4145a8c (patch) | |
tree | 6d3c8ddd442e4cd96f1f8bdcf59fcaef72f4edc9 /Documentation/ABI | |
parent | a137e1cc6d6e7d315fef03962a2a5a113348b13b (diff) | |
download | lwn-a3437870160cf2caaac6bdd76c7377a5a4145a8c.tar.gz lwn-a3437870160cf2caaac6bdd76c7377a5a4145a8c.zip |
hugetlb: new sysfs interface
Provide new hugepages user APIs that are more suited to multiple hstates
in sysfs. There is a new directory, /sys/kernel/hugepages. Underneath
that directory there will be a directory per-supported hugepage size,
e.g.:
/sys/kernel/hugepages/hugepages-64kB
/sys/kernel/hugepages/hugepages-16384kB
/sys/kernel/hugepages/hugepages-16777216kB
corresponding to 64k, 16m and 16g respectively. Within each
hugepages-size directory there are a number of files, corresponding to the
tracked counters in the hstate, e.g.:
/sys/kernel/hugepages/hugepages-64/nr_hugepages
/sys/kernel/hugepages/hugepages-64/nr_overcommit_hugepages
/sys/kernel/hugepages/hugepages-64/free_hugepages
/sys/kernel/hugepages/hugepages-64/resv_hugepages
/sys/kernel/hugepages/hugepages-64/surplus_hugepages
Of these files, the first two are read-write and the latter three are
read-only. The size of the hugepage being manipulated is trivially
deducible from the enclosing directory and is always expressed in kB (to
match meminfo).
[dave@linux.vnet.ibm.com: fix build]
[nacc@us.ibm.com: hugetlb: hang off of /sys/kernel/mm rather than /sys/kernel]
[nacc@us.ibm.com: hugetlb: remove CONFIG_SYSFS dependency]
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Nishanth Aravamudan <nacc@us.ibm.com>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Dave Hansen <dave@linux.vnet.ibm.com>
Signed-off-by: Nishanth Aravamudan <nacc@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'Documentation/ABI')
-rw-r--r-- | Documentation/ABI/testing/sysfs-kernel-mm-hugepages | 15 |
1 files changed, 15 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 @@ +What: /sys/kernel/mm/hugepages/ +Date: June 2008 +Contact: Nishanth Aravamudan <nacc@us.ibm.com>, hugetlb maintainers +Description: + /sys/kernel/mm/hugepages/ contains a number of subdirectories + of the form hugepages-<size>kB, where <size> is the page size + of the hugepages supported by the kernel/CPU combination. + + Under these directories are a number of files: + nr_hugepages + nr_overcommit_hugepages + free_hugepages + surplus_hugepages + resv_hugepages + See Documentation/vm/hugetlbpage.txt for details. |