| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-Id: <1427092244-22764-1-git-send-email-namhyung@kernel.org>
Date: Mon, 23 Mar 2015 15:30:39 +0900
From: Namhyung Kim <namhyung@...nel.org>
To: Arnaldo Carvalho de Melo <acme@...nel.org>
Cc: Ingo Molnar <mingo@...nel.org>,
Peter Zijlstra <a.p.zijlstra@...llo.nl>,
Jiri Olsa <jolsa@...hat.com>,
LKML <linux-kernel@...r.kernel.org>,
David Ahern <dsahern@...il.com>,
Minchan Kim <minchan@...nel.org>,
Joonsoo Kim <js1304@...il.com>
Subject: [PATCHSET 0/5] perf kmem: Implement page allocation analysis (v3)
Hello,
Currently perf kmem command only analyzes SLAB memory allocation. And
I'd like to introduce page allocation analysis also. Users can use
--slab and/or --page option to select it. If none of these options
are used, it does slab allocation analysis for backward compatibility.
* changes in v3)
- add live page statistics
* changes in v2)
- Use thousand grouping for big numbers - i.e. 12345 -> 12,345 (Ingo)
- Improve output stat readability (Ingo)
- Remove alloc size column as it can be calculated from hits and order
Patch 1 is to support thousand grouping on stat output. Patch 2
implements basic support for page allocation analysis, patch 3 deals
with the callsite and finally patch 4 implements sorting.
In this patchset, I used two kmem events: kmem:mm_page_alloc and
kmem_page_free for analysis as they can track almost all of memory
allocation/free path AFAIK. However, unlike slab tracepoint events,
those page allocation events don't provide callsite info directly. So
I recorded callchains and extracted callsites like below:
Normal page allocation callchains look like this:
360a7e __alloc_pages_nodemask
3a711c alloc_pages_current
357bc7 __page_cache_alloc <-- callsite
357cf6 pagecache_get_page
48b0a prepare_pages
494d3 __btrfs_buffered_write
49cdf btrfs_file_write_iter
3ceb6e new_sync_write
3cf447 vfs_write
3cff99 sys_write
7556e9 system_call
f880 __write_nocancel
33eb9 cmd_record
4b38e cmd_kmem
7aa23 run_builtin
27a9a main
20800 __libc_start_main
But first two are internal page allocation functions so it should be
skipped. To determine such allocation functions, I used following regex:
^_?_?(alloc|get_free|get_zeroed)_pages?
This gave me a following list of functions (you can see this with -v):
alloc func: __get_free_pages
alloc func: get_zeroed_page
alloc func: alloc_pages_exact
alloc func: __alloc_pages_direct_compact
alloc func: __alloc_pages_nodemask
alloc func: alloc_page_interleave
alloc func: alloc_pages_current
alloc func: alloc_pages_vma
alloc func: alloc_page_buffers
alloc func: alloc_pages_exact_nid
After skipping those function, it got '__page_cache_alloc'.
Other information such as allocation order, migration type and gfp
flags are provided by tracepoint events.
Basically the output will be sorted by total allocation bytes, but you
can change it by using -s/--sort option. The following sort keys are
added to support page analysis: page, order, mtype, gfp. Existing
'callsite', 'bytes' and 'hit' sort keys also can be used.
An example follows:
# perf kmem record --slab --page sleep 1
[ perf record: Woken up 0 times to write data ]
[ perf record: Captured and wrote 49.277 MB perf.data (191027 samples) ]
# perf kmem stat --page --caller -l 10 -s order,hit
--------------------------------------------------------------------------------------------
Total alloc (KB) | Hits | Order | Migration type | GFP flags | Callsite
--------------------------------------------------------------------------------------------
64 | 4 | 2 | RECLAIMABLE | 00285250 | new_slab
50,144 | 12,536 | 0 | MOVABLE | 0102005a | __page_cache_alloc
52 | 13 | 0 | UNMOVABLE | 002084d0 | pte_alloc_one
40 | 10 | 0 | MOVABLE | 000280da | handle_mm_fault
28 | 7 | 0 | UNMOVABLE | 000000d0 | __pollwait
20 | 5 | 0 | MOVABLE | 000200da | do_wp_page
20 | 5 | 0 | MOVABLE | 000200da | do_cow_fault
16 | 4 | 0 | UNMOVABLE | 00000200 | __tlb_remove_page
16 | 4 | 0 | UNMOVABLE | 000084d0 | __pmd_alloc
8 | 2 | 0 | UNMOVABLE | 000084d0 | __pud_alloc
... | ... | ... | ... | ... | ...
--------------------------------------------------------------------------------------------
SUMMARY (page allocator)
========================
Total allocation requests : 12,594 [ 50,420 KB ]
Total free requests : 182 [ 728 KB ]
Total alloc+freed requests : 115 [ 460 KB ]
Total alloc-only requests : 12,479 [ 49,960 KB ]
Total free-only requests : 67 [ 268 KB ]
Total allocation failures : 0 [ 0 KB ]
Order Unmovable Reclaimable Movable Reserved CMA/Isolated
----- ------------ ------------ ------------ ------------ ------------
0 32 . 12,558 . .
1 . . . . .
2 . 4 . . .
3 . . . . .
4 . . . . .
5 . . . . .
6 . . . . .
7 . . . . .
8 . . . . .
9 . . . . .
10 . . . . .
I have some idea how to improve it. But I'd also like to hear other
idea, suggestion, feedback and so on.
This is available at perf/kmem-page-v3 branch on my tree:
git://git.kernel.org/pub/scm/linux/kernel/git/namhyung/linux-perf.git
Thanks,
Namhyung
Namhyung Kim (5):
perf kmem: Print big numbers using thousands' group
perf kmem: Analyze page allocator events also
perf kmem: Implement stat --page --caller
perf kmem: Support sort keys on page analysis
perf kmem: Add --live option for current allocation stat
tools/perf/Documentation/perf-kmem.txt | 19 +-
tools/perf/builtin-kmem.c | 1065 ++++++++++++++++++++++++++++++--
2 files changed, 1022 insertions(+), 62 deletions(-)
--
2.3.3
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists