[PATCH v5 1/6] mm, documentation: clarify /proc/pid/status VmSwap limitations for shmem

From: Vlastimil Babka
Date: Wed Nov 18 2015 - 04:30:07 EST


The documentation for /proc/pid/status does not mention that the value of
VmSwap counts only swapped out anonymous private pages, and not swapped out
pages of the underlying shmem objects (for shmem mappings). This is not
obvious, so document this limitation.

Signed-off-by: Vlastimil Babka <vbabka@xxxxxxx>
Acked-by: Konstantin Khlebnikov <khlebnikov@xxxxxxxxxxxxxx>
Acked-by: Michal Hocko <mhocko@xxxxxxxx>
Acked-by: Jerome Marchand <jmarchan@xxxxxxxxxx>
Acked-by: Hugh Dickins <hughd@xxxxxxxxxx>
---
Documentation/filesystems/proc.txt | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt
index 402ab99..9f13b6e 100644
--- a/Documentation/filesystems/proc.txt
+++ b/Documentation/filesystems/proc.txt
@@ -238,7 +238,8 @@ Table 1-2: Contents of the status files (as of 4.1)
VmLib size of shared library code
VmPTE size of page table entries
VmPMD size of second level page tables
- VmSwap size of swap usage (the number of referred swapents)
+ VmSwap amount of swap used by anonymous private data
+ (shmem swap usage is not included)
HugetlbPages size of hugetlb memory portions
Threads number of threads
SigQ number of signals queued/max. number for queue
--
2.6.3

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/