Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1509374 > unrolled thread

Re: [v3,6/9] mm/page_owner: use stackdepot to store stacktrace

Started bySascha Silbe <x-linux@infra-silbe.de>
First post2016-10-26 15:20 +0200
Last post2016-10-27 02:20 +0200
Articles 2 — 2 participants

Back to article view | Back to linux.kernel

This discussion starts older than the indexed window; earlier articles aren't shown. The article labeled Started by below is the oldest one visible, not the original post.


Contents

  Re: [v3,6/9] mm/page_owner: use stackdepot to store stacktrace Sascha Silbe <x-linux@infra-silbe.de> - 2016-10-26 15:20 +0200
    Re: [v3,6/9] mm/page_owner: use stackdepot to store stacktrace Joonsoo Kim <iamjoonsoo.kim@lge.com> - 2016-10-27 02:20 +0200

#1509374 — Re: [v3,6/9] mm/page_owner: use stackdepot to store stacktrace

FromSascha Silbe <x-linux@infra-silbe.de>
Date2016-10-26 15:20 +0200
SubjectRe: [v3,6/9] mm/page_owner: use stackdepot to store stacktrace
Message-ID<swwhA-4d2-47@gated-at.bofh.it>

[Multipart message — attachments visible in raw view] — view raw

Dear Joonsoo,

Joonsoo Kim <js1304@gmail.com> writes:

> Currently, we store each page's allocation stacktrace on corresponding
> page_ext structure and it requires a lot of memory.  This causes the
> problem that memory tight system doesn't work well if page_owner is
> enabled.  Moreover, even with this large memory consumption, we cannot get
> full stacktrace because we allocate memory at boot time and just maintain
> 8 stacktrace slots to balance memory consumption.  We could increase it to
> more but it would make system unusable or change system behaviour.
[...]

This patch causes my Wandboard Quad [1] not to boot anymore. I don't get
any kernel output, even with earlycon enabled
(earlycon=ec_imx6q,0x02020000). git bisect pointed towards your patch;
reverting the patch causes the system to boot fine again. Config is
available at [2]; none of the defconfigs I tried (defconfig =
multi_v7_defconfig, imx_v6_v7_defconfig) works for me.

Haven't looked into this any further so far; hooking up a JTAG adapter
requires some hardware changes as the JTAG header is unpopulated.

Sascha

PS: Please CC me on replies; I'm not subscribed to any of the lists.

[1] http://www.wandboard.org/index.php/details/wandboard
[2] https://sascha.silbe.org/tmp/config-4.8.4-wandboard-28-00003-g9e9b5d6
-- 
Softwareentwicklung Sascha Silbe, Niederhofenstraße 5/1, 71229 Leonberg
https://se-silbe.de/
USt-IdNr.: DE281696641

[toc] | [next] | [standalone]


#1509977

FromJoonsoo Kim <iamjoonsoo.kim@lge.com>
Date2016-10-27 02:20 +0200
Message-ID<swGAh-2IM-9@gated-at.bofh.it>
In reply to#1509374
Hello,

Thanks for the report.

On Wed, Oct 26, 2016 at 03:06:05PM +0200, Sascha Silbe wrote:
> Dear Joonsoo,
> 
> Joonsoo Kim <js1304@gmail.com> writes:
> 
> > Currently, we store each page's allocation stacktrace on corresponding
> > page_ext structure and it requires a lot of memory.  This causes the
> > problem that memory tight system doesn't work well if page_owner is
> > enabled.  Moreover, even with this large memory consumption, we cannot get
> > full stacktrace because we allocate memory at boot time and just maintain
> > 8 stacktrace slots to balance memory consumption.  We could increase it to
> > more but it would make system unusable or change system behaviour.
> [...]
> 
> This patch causes my Wandboard Quad [1] not to boot anymore. I don't get
> any kernel output, even with earlycon enabled
> (earlycon=ec_imx6q,0x02020000). git bisect pointed towards your patch;
> reverting the patch causes the system to boot fine again. Config is
> available at [2]; none of the defconfigs I tried (defconfig =
> multi_v7_defconfig, imx_v6_v7_defconfig) works for me.
> 
> Haven't looked into this any further so far; hooking up a JTAG adapter
> requires some hardware changes as the JTAG header is unpopulated.
> 
> Sascha
> 
> PS: Please CC me on replies; I'm not subscribed to any of the lists.
> 
> [1] http://www.wandboard.org/index.php/details/wandboard
> [2] https://sascha.silbe.org/tmp/config-4.8.4-wandboard-28-00003-g9e9b5d6
> -- 
> Softwareentwicklung Sascha Silbe, Niederhofenstraße 5/1, 71229 Leonberg
> https://se-silbe.de/
> USt-IdNr.: DE281696641


I cannot see your config. Link [2] shows "No such file or directory"

Anyway, I find that there is an issue in early boot phase in
!CONFIG_SPARSEMEM. Could you try following one?
(It's an completely untested patch, even I don't try to compile it.)

Thanks.

---------->8---------------
diff --git a/include/linux/page_ext.h b/include/linux/page_ext.h
index 9298c39..db31f58 100644
--- a/include/linux/page_ext.h
+++ b/include/linux/page_ext.h
@@ -47,6 +47,7 @@ struct page_ext {
 };
 
 extern void pgdat_page_ext_init(struct pglist_data *pgdat);
+extern void __init invoke_init_callbacks(void);
 
 #ifdef CONFIG_SPARSEMEM
 static inline void page_ext_init_flatmem(void)
@@ -57,6 +58,7 @@ static inline void page_ext_init_flatmem(void)
 extern void page_ext_init_flatmem(void);
 static inline void page_ext_init(void)
 {
+       invoke_init_callbacks();
 }
 #endif
 
diff --git a/mm/page_ext.c b/mm/page_ext.c
index 121dcff..a405869 100644
--- a/mm/page_ext.c
+++ b/mm/page_ext.c
@@ -91,7 +91,7 @@ static bool __init invoke_need_callbacks(void)
        return need;
 }
 
-static void __init invoke_init_callbacks(void)
+void __init invoke_init_callbacks(void)
 {
        int i;
        int entries = ARRAY_SIZE(page_ext_ops);
@@ -190,7 +190,6 @@ void __init page_ext_init_flatmem(void)
                        goto fail;
        }
        pr_info("allocated %ld bytes of page_ext\n", total_usage);
-       invoke_init_callbacks();
        return;
 
 fail:

[toc] | [prev] | [standalone]


Back to top | Article view | linux.kernel


csiph-web