From: Lorenzo Stoakes <lstoakes@gmail.com>
To: "Uladzislau Rezki (Sony)" <urezki@gmail.com>
Cc: linux-mm@kvack.org, Andrew Morton <akpm@linux-foundation.org>,
LKML <linux-kernel@vger.kernel.org>, Baoquan He <bhe@redhat.com>,
Christoph Hellwig <hch@infradead.org>,
Matthew Wilcox <willy@infradead.org>,
"Liam R . Howlett" <Liam.Howlett@oracle.com>,
Dave Chinner <david@fromorbit.com>,
"Paul E . McKenney" <paulmck@kernel.org>,
Joel Fernandes <joel@joelfernandes.org>,
Oleksiy Avramchenko <oleksiy.avramchenko@sony.com>
Subject: Re: [PATCH v2 0/9] Mitigate a vmap lock contention v2
Date: Wed, 6 Sep 2023 21:04:26 +0100 [thread overview]
Message-ID: <a21df9dc-ded7-4882-b0e7-688fce4d20b6@lucifer.local> (raw)
In-Reply-To: <20230829081142.3619-1-urezki@gmail.com>
On Tue, Aug 29, 2023 at 10:11:33AM +0200, Uladzislau Rezki (Sony) wrote:
> Hello, folk!
>
> This is the v2, the series which tends to minimize the vmap
> lock contention. It is based on the tag: v6.5-rc6. Here you
> can find a documentation about it:
Will take a look when I get a chance at v3 as I gather you're spinning
another version :)
Cheers!
>
> wget ftp://vps418301.ovh.net/incoming/Fix_a_vmalloc_lock_contention_in_SMP_env_v2.pdf
>
> even though it is a bit outdated(it follows v1), it still gives a
> good overview on the problem and how it can be solved. On demand
> and by request i can update it.
>
> The v1 is here: https://lore.kernel.org/linux-mm/ZIAqojPKjChJTssg@pc636/T/
>
> Delta v1 -> v2:
> - open coded locking;
> - switch to array of nodes instead of per-cpu definition;
> - density is 2 cores per one node(not equal to number of CPUs);
> - VAs first go back(free path) to an owner node and later to
> a global heap if a block is fully freed, nid is saved in va->flags;
> - add helpers to drain lazily-freed areas faster, if high pressure;
> - picked al Reviewed-by.
>
> Test on AMD Ryzen Threadripper 3970X 32-Core Processor:
> sudo ./test_vmalloc.sh run_test_mask=127 nr_threads=64
>
> <v6.5-rc6 perf>
> 94.17% 0.90% [kernel] [k] _raw_spin_lock
> 93.27% 93.05% [kernel] [k] native_queued_spin_lock_slowpath
> 74.69% 0.25% [kernel] [k] __vmalloc_node_range
> 72.64% 0.01% [kernel] [k] __get_vm_area_node
> 72.04% 0.89% [kernel] [k] alloc_vmap_area
> 42.17% 0.00% [kernel] [k] vmalloc
> 32.53% 0.00% [kernel] [k] __vmalloc_node
> 24.91% 0.25% [kernel] [k] vfree
> 24.32% 0.01% [kernel] [k] remove_vm_area
> 22.63% 0.21% [kernel] [k] find_unlink_vmap_area
> 15.51% 0.00% [unknown] [k] 0xffffffffc09a74ac
> 14.35% 0.00% [kernel] [k] ret_from_fork_asm
> 14.35% 0.00% [kernel] [k] ret_from_fork
> 14.35% 0.00% [kernel] [k] kthread
> <v6.5-rc6 perf>
> vs
> <v6.5-rc6+v2 perf>
> 74.32% 2.42% [kernel] [k] __vmalloc_node_range
> 69.58% 0.01% [kernel] [k] vmalloc
> 54.21% 1.17% [kernel] [k] __alloc_pages_bulk
> 48.13% 47.91% [kernel] [k] clear_page_orig
> 43.60% 0.01% [unknown] [k] 0xffffffffc082f16f
> 32.06% 0.00% [kernel] [k] ret_from_fork_asm
> 32.06% 0.00% [kernel] [k] ret_from_fork
> 32.06% 0.00% [kernel] [k] kthread
> 31.30% 0.00% [unknown] [k] 0xffffffffc082f889
> 22.98% 4.16% [kernel] [k] vfree
> 14.36% 0.28% [kernel] [k] __get_vm_area_node
> 13.43% 3.35% [kernel] [k] alloc_vmap_area
> 10.86% 0.04% [kernel] [k] remove_vm_area
> 8.89% 2.75% [kernel] [k] _raw_spin_lock
> 7.19% 0.00% [unknown] [k] 0xffffffffc082fba3
> 6.65% 1.37% [kernel] [k] free_unref_page
> 6.13% 6.11% [kernel] [k] native_queued_spin_lock_slowpath
> <v6.5-rc6+v2 perf>
>
> On smaller systems, for example, 8xCPU Hikey960 board the
> contention is not that high and is approximately ~16 percent.
>
> Uladzislau Rezki (Sony) (9):
> mm: vmalloc: Add va_alloc() helper
> mm: vmalloc: Rename adjust_va_to_fit_type() function
> mm: vmalloc: Move vmap_init_free_space() down in vmalloc.c
> mm: vmalloc: Remove global vmap_area_root rb-tree
> mm: vmalloc: Remove global purge_vmap_area_root rb-tree
> mm: vmalloc: Offload free_vmap_area_lock lock
> mm: vmalloc: Support multiple nodes in vread_iter
> mm: vmalloc: Support multiple nodes in vmallocinfo
> mm: vmalloc: Set nr_nodes/node_size based on CPU-cores
>
> mm/vmalloc.c | 929 +++++++++++++++++++++++++++++++++++++--------------
> 1 file changed, 683 insertions(+), 246 deletions(-)
>
> --
> 2.30.2
>
next prev parent reply other threads:[~2023-09-06 20:04 UTC|newest]
Thread overview: 62+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-08-29 8:11 [PATCH v2 0/9] Mitigate a vmap lock contention v2 Uladzislau Rezki (Sony)
2023-08-29 8:11 ` [PATCH v2 1/9] mm: vmalloc: Add va_alloc() helper Uladzislau Rezki (Sony)
2023-09-06 5:51 ` Baoquan He
2023-09-06 15:06 ` Uladzislau Rezki
2023-08-29 8:11 ` [PATCH v2 2/9] mm: vmalloc: Rename adjust_va_to_fit_type() function Uladzislau Rezki (Sony)
2023-09-06 5:51 ` Baoquan He
2023-09-06 16:27 ` Uladzislau Rezki
2023-08-29 8:11 ` [PATCH v2 3/9] mm: vmalloc: Move vmap_init_free_space() down in vmalloc.c Uladzislau Rezki (Sony)
2023-09-06 5:52 ` Baoquan He
2023-09-06 16:29 ` Uladzislau Rezki
2023-08-29 8:11 ` [PATCH v2 4/9] mm: vmalloc: Remove global vmap_area_root rb-tree Uladzislau Rezki (Sony)
2023-08-29 14:30 ` kernel test robot
2023-08-30 14:48 ` Uladzislau Rezki
2023-09-07 2:17 ` Baoquan He
2023-09-07 9:38 ` Baoquan He
2023-09-07 9:40 ` Uladzislau Rezki
2023-09-07 9:39 ` Uladzislau Rezki
2023-09-07 9:58 ` Baoquan He
2023-09-08 1:51 ` HAGIO KAZUHITO(萩尾 一仁)
2023-09-08 4:43 ` Baoquan He
2023-09-08 5:01 ` HAGIO KAZUHITO(萩尾 一仁)
2023-09-08 6:44 ` Baoquan He
2023-09-08 11:25 ` Uladzislau Rezki
2023-09-08 11:38 ` Baoquan He
2023-09-08 13:23 ` Uladzislau Rezki
2023-09-11 2:38 ` Baoquan He
2023-09-11 16:53 ` Uladzislau Rezki
2023-09-12 13:19 ` Baoquan He
2023-08-29 8:11 ` [PATCH v2 5/9] mm: vmalloc: Remove global purge_vmap_area_root rb-tree Uladzislau Rezki (Sony)
2023-09-11 2:57 ` Baoquan He
2023-09-11 17:00 ` Uladzislau Rezki
2023-08-29 8:11 ` [PATCH v2 6/9] mm: vmalloc: Offload free_vmap_area_lock lock Uladzislau Rezki (Sony)
2023-09-06 6:04 ` Baoquan He
2023-09-06 19:16 ` Uladzislau Rezki
2023-09-07 0:06 ` Baoquan He
2023-09-07 9:33 ` Uladzislau Rezki
2023-09-11 3:25 ` Baoquan He
2023-09-11 17:10 ` Uladzislau Rezki
2023-09-12 13:21 ` Baoquan He
2023-08-29 8:11 ` [PATCH v2 7/9] mm: vmalloc: Support multiple nodes in vread_iter Uladzislau Rezki (Sony)
2023-09-11 3:58 ` Baoquan He
2023-09-11 18:16 ` Uladzislau Rezki
2023-09-12 13:42 ` Baoquan He
2023-09-13 15:42 ` Uladzislau Rezki
2023-09-14 3:02 ` Baoquan He
2023-09-14 3:36 ` Baoquan He
2023-09-14 3:38 ` Baoquan He
2023-09-13 10:59 ` Baoquan He
2023-09-13 15:38 ` Uladzislau Rezki
2023-08-29 8:11 ` [PATCH v2 8/9] mm: vmalloc: Support multiple nodes in vmallocinfo Uladzislau Rezki (Sony)
2023-09-15 13:02 ` Baoquan He
2023-09-15 18:32 ` Uladzislau Rezki
2023-08-29 8:11 ` [PATCH v2 9/9] mm: vmalloc: Set nr_nodes/node_size based on CPU-cores Uladzislau Rezki (Sony)
2023-09-15 13:03 ` Baoquan He
2023-09-15 18:31 ` Uladzislau Rezki
2023-08-31 1:15 ` [PATCH v2 0/9] Mitigate a vmap lock contention v2 Baoquan He
2023-08-31 16:26 ` Uladzislau Rezki
2023-09-04 14:55 ` Uladzislau Rezki
2023-09-04 19:53 ` Andrew Morton
2023-09-05 6:53 ` Uladzislau Rezki
2023-09-06 20:04 ` Lorenzo Stoakes [this message]
2023-09-07 9:15 ` Uladzislau Rezki
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=a21df9dc-ded7-4882-b0e7-688fce4d20b6@lucifer.local \
--to=lstoakes@gmail.com \
--cc=Liam.Howlett@oracle.com \
--cc=akpm@linux-foundation.org \
--cc=bhe@redhat.com \
--cc=david@fromorbit.com \
--cc=hch@infradead.org \
--cc=joel@joelfernandes.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=oleksiy.avramchenko@sony.com \
--cc=paulmck@kernel.org \
--cc=urezki@gmail.com \
--cc=willy@infradead.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).