From 198d1597cc5a12d04af18b69338a5b1d66ee7020 Mon Sep 17 00:00:00 2001 From: Rafael Aquini Date: Thu, 12 Feb 2015 15:01:08 -0800 Subject: [PATCH] fs: proc: task_mmu: show page size in /proc//numa_maps The output of /proc/$pid/numa_maps is in terms of number of pages like anon=22 or dirty=54. Here's some output: 7f4680000000 default file=/hugetlb/bigfile anon=50 dirty=50 N0=50 7f7659600000 default file=/anon_hugepage\040(deleted) anon=50 dirty=50 N0=50 7fff8d425000 default stack anon=50 dirty=50 N0=50 Looks like we have a stack and a couple of anonymous hugetlbfs areas page which both use the same amount of memory. They don't. The 'bigfile' uses 1GB pages and takes up ~50GB of space. The anon_hugepage uses 2MB pages and takes up ~100MB of space while the stack uses normal 4k pages. You can go over to smaps to figure out what the page size _really_ is with KernelPageSize or MMUPageSize. But, I think this is a pretty nasty and counterintuitive interface as it stands. This patch introduces 'kernelpagesize_kB' line element to /proc//numa_maps report file in order to help identifying the size of pages that are backing memory areas mapped by a given task. This is specially useful to help differentiating between HUGE and GIGANTIC page backed VMAs. This patch is based on Dave Hansen's proposal and reviewer's follow-ups taken from the following dicussion threads: * https://lkml.org/lkml/2011/9/21/454 * https://lkml.org/lkml/2014/12/20/66 Signed-off-by: Rafael Aquini Cc: Johannes Weiner Cc: Dave Hansen Acked-by: David Rientjes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/filesystems/proc.txt | 30 +++++++++++++++--------------- fs/proc/task_mmu.c | 2 ++ 2 files changed, 17 insertions(+), 15 deletions(-) diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt index ff3eb2380831..a07ba61662ed 100644 --- a/Documentation/filesystems/proc.txt +++ b/Documentation/filesystems/proc.txt @@ -508,22 +508,22 @@ summarized separated by blank spaces, one mapping per each file line: address policy mapping details -00400000 default file=/usr/local/bin/app kernelpagesize_kB=4 mapped=1 active=0 N3=1 -00600000 default file=/usr/local/bin/app kernelpagesize_kB=4 anon=1 dirty=1 N3=1 -3206000000 default file=/lib64/ld-2.12.so kernelpagesize_kB=4 mapped=26 mapmax=6 N0=24 N3=2 -320621f000 default file=/lib64/ld-2.12.so kernelpagesize_kB=4 anon=1 dirty=1 N3=1 -3206220000 default file=/lib64/ld-2.12.so kernelpagesize_kB=4 anon=1 dirty=1 N3=1 -3206221000 default kernelpagesize_kB=4 anon=1 dirty=1 N3=1 -3206800000 default file=/lib64/libc-2.12.so kernelpagesize_kB=4 mapped=59 mapmax=21 active=55 N0=41 N3=18 +00400000 default file=/usr/local/bin/app mapped=1 active=0 N3=1 kernelpagesize_kB=4 +00600000 default file=/usr/local/bin/app anon=1 dirty=1 N3=1 kernelpagesize_kB=4 +3206000000 default file=/lib64/ld-2.12.so mapped=26 mapmax=6 N0=24 N3=2 kernelpagesize_kB=4 +320621f000 default file=/lib64/ld-2.12.so anon=1 dirty=1 N3=1 kernelpagesize_kB=4 +3206220000 default file=/lib64/ld-2.12.so anon=1 dirty=1 N3=1 kernelpagesize_kB=4 +3206221000 default anon=1 dirty=1 N3=1 kernelpagesize_kB=4 +3206800000 default file=/lib64/libc-2.12.so mapped=59 mapmax=21 active=55 N0=41 N3=18 kernelpagesize_kB=4 320698b000 default file=/lib64/libc-2.12.so -3206b8a000 default file=/lib64/libc-2.12.so kernelpagesize_kB=4 anon=2 dirty=2 N3=2 -3206b8e000 default file=/lib64/libc-2.12.so kernelpagesize_kB=4 anon=1 dirty=1 N3=1 -3206b8f000 default kernelpagesize_kB=4 anon=3 dirty=3 active=1 N3=3 -7f4dc10a2000 default kernelpagesize_kB=4 anon=3 dirty=3 N3=3 -7f4dc10b4000 default kernelpagesize_kB=4 anon=2 dirty=2 active=1 N3=2 -7f4dc1200000 default file=/anon_hugepage\040(deleted) huge kernelpagesize_kB=2048 anon=1 dirty=1 N3=1 -7fff335f0000 default stack kernelpagesize_kB=4 anon=3 dirty=3 N3=3 -7fff3369d000 default kernelpagesize_kB=4 mapped=1 mapmax=35 active=0 N3=1 +3206b8a000 default file=/lib64/libc-2.12.so anon=2 dirty=2 N3=2 kernelpagesize_kB=4 +3206b8e000 default file=/lib64/libc-2.12.so anon=1 dirty=1 N3=1 kernelpagesize_kB=4 +3206b8f000 default anon=3 dirty=3 active=1 N3=3 kernelpagesize_kB=4 +7f4dc10a2000 default anon=3 dirty=3 N3=3 kernelpagesize_kB=4 +7f4dc10b4000 default anon=2 dirty=2 active=1 N3=2 kernelpagesize_kB=4 +7f4dc1200000 default file=/anon_hugepage\040(deleted) huge anon=1 dirty=1 N3=1 kernelpagesize_kB=2048 +7fff335f0000 default stack anon=3 dirty=3 N3=3 kernelpagesize_kB=4 +7fff3369d000 default mapped=1 mapmax=35 active=0 N3=1 kernelpagesize_kB=4 Where: "address" is the starting address for the mapping; diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c index 1359a911d194..956b75d61809 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -1557,6 +1557,8 @@ static int show_numa_map(struct seq_file *m, void *v, int is_pid) for_each_node_state(nid, N_MEMORY) if (md->node[nid]) seq_printf(m, " N%d=%lu", nid, md->node[nid]); + + seq_printf(m, " kernelpagesize_kB=%lu", vma_kernel_pagesize(vma) >> 10); out: seq_putc(m, '\n'); m_cache_vma(m, vma); -- 2.30.2