mm: hugetlb: proc: add hugetlb-related fields to /proc/PID/smaps
Currently /proc/PID/smaps provides no usage info for vma(VM_HUGETLB),
which is inconvenient when we want to know per-task or per-vma base
hugetlb usage. To solve this, this patch adds new fields for hugetlb
usage like below:
Size: 20480 kB
Rss: 0 kB
Pss: 0 kB
Shared_Clean: 0 kB
Shared_Dirty: 0 kB
Private_Clean: 0 kB
Private_Dirty: 0 kB
Referenced: 0 kB
Anonymous: 0 kB
AnonHugePages: 0 kB
Shared_Hugetlb: 18432 kB
Private_Hugetlb: 2048 kB
Swap: 0 kB
KernelPageSize: 2048 kB
MMUPageSize: 2048 kB
Locked: 0 kB
VmFlags: rd wr mr mw me de ht
[hughd@google.com: fix Private_Hugetlb alignment ]
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Acked-by: Joern Engel <joern@logfs.org>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt
index 3a9d65c..a7d6c06 100644
--- a/Documentation/filesystems/proc.txt
+++ b/Documentation/filesystems/proc.txt
@@ -424,6 +424,9 @@
Private_Dirty: 0 kB
Referenced: 892 kB
Anonymous: 0 kB
+AnonHugePages: 0 kB
+Shared_Hugetlb: 0 kB
+Private_Hugetlb: 0 kB
Swap: 0 kB
SwapPss: 0 kB
KernelPageSize: 4 kB
@@ -452,6 +455,11 @@
"Swap" shows how much would-be-anonymous memory is also used, but out on
swap.
"SwapPss" shows proportional swap share of this mapping.
+"AnonHugePages" shows the ammount of memory backed by transparent hugepage.
+"Shared_Hugetlb" and "Private_Hugetlb" show the ammounts of memory backed by
+hugetlbfs page which is *not* counted in "RSS" or "PSS" field for historical
+reasons. And these are not included in {Shared,Private}_{Clean,Dirty} field.
+
"VmFlags" field deserves a separate description. This member represents the kernel
flags associated with the particular virtual memory area in two letter encoded
manner. The codes are the following: