From: Ralph Campbell <rcampbell@nvidia.com>
To: Michal Hocko <mhocko@kernel.org>, Vlastimil Babka <vbabka@suse.cz>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>,
David Hildenbrand <david@redhat.com>, Qian Cai <cai@lca.pw>,
<linux-mm@kvack.org>, Andrew Morton <akpm@linux-foundation.org>,
Oscar Salvador <osalvador@suse.de>,
Mel Gorman <mgorman@techsingularity.net>,
Mike Rapoport <rppt@linux.ibm.com>,
Dan Williams <dan.j.williams@intel.com>,
Pavel Tatashin <pavel.tatashin@microsoft.com>,
<linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] mm/page_alloc: Add a reason for reserved pages in has_unmovable_pages()
Date: Tue, 14 Jan 2020 10:22:48 -0800 [thread overview]
Message-ID: <958fa7cd-0e88-3387-d4bf-e8bfcfdb256b@nvidia.com> (raw)
In-Reply-To: <20200114113230.GM19428@dhcp22.suse.cz>
On 1/14/20 3:32 AM, Michal Hocko wrote:
> On Tue 14-01-20 11:23:52, Vlastimil Babka wrote:
>> On 1/14/20 10:10 AM, Michal Hocko wrote:
>>> [Cc Ralph]
>>>> The reason is dump_page() does not print page->flags universally
>>>> and only does so for KSM, Anon and File pages while excluding
>>>> reserved pages at boot. Wondering should not we make printing
>>>> page->flags universal ?
>>>
>>> We used to do that and this caught me as a surprise when looking again.
>>> This is a result of 76a1850e4572 ("mm/debug.c: __dump_page() prints an
>>> extra line") which is a cleanup patch and I suspect this result was not
>>> anticipated.
>>>
>>> The following will do the trick but I cannot really say I like the code
>>> duplication. pr_cont in this case sounds like a much cleaner solution to
>>> me.
>>
>> How about this then?
>
> Yes makes sense as well.
>
>> diff --git mm/debug.c mm/debug.c
>> index 0461df1207cb..6a52316af839 100644
>> --- mm/debug.c
>> +++ mm/debug.c
>> @@ -47,6 +47,7 @@ void __dump_page(struct page *page, const char *reason)
>> struct address_space *mapping;
>> bool page_poisoned = PagePoisoned(page);
>> int mapcount;
>> + char *type = "";
>>
>> /*
>> * If struct page is poisoned don't access Page*() functions as that
>> @@ -78,9 +79,9 @@ void __dump_page(struct page *page, const char *reason)
>> page, page_ref_count(page), mapcount,
>> page->mapping, page_to_pgoff(page));
>> if (PageKsm(page))
>> - pr_warn("ksm flags: %#lx(%pGp)\n", page->flags, &page->flags);
>> + type = "ksm ";
>> else if (PageAnon(page))
>> - pr_warn("anon flags: %#lx(%pGp)\n", page->flags, &page->flags);
>> + type = "anon ";
>> else if (mapping) {
>> if (mapping->host && mapping->host->i_dentry.first) {
>> struct dentry *dentry;
>> @@ -88,10 +89,11 @@ void __dump_page(struct page *page, const char *reason)
>> pr_warn("%ps name:\"%pd\"\n", mapping->a_ops, dentry);
>> } else
>> pr_warn("%ps\n", mapping->a_ops);
>> - pr_warn("flags: %#lx(%pGp)\n", page->flags, &page->flags);
>> }
>> BUILD_BUG_ON(ARRAY_SIZE(pageflag_names) != __NR_PAGEFLAGS + 1);
>>
>> + pr_warn("%sflags: %#lx(%pGp)\n", type, page->flags, &page->flags);
>> +
>> hex_only:
>> print_hex_dump(KERN_WARNING, "raw: ", DUMP_PREFIX_NONE, 32,
>> sizeof(unsigned long), page,
>>
>
Looks good to me. Thanks for the clean up.
Reviewed-by: Ralph Campbell <rcampbell@nvidia.com>
next prev parent reply other threads:[~2020-01-14 18:22 UTC|newest]
Thread overview: 29+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-10-03 8:10 [PATCH] mm/page_alloc: Add a reason for reserved pages in has_unmovable_pages() Anshuman Khandual
2019-10-03 9:05 ` Qian Cai
2019-10-03 9:32 ` Anshuman Khandual
2019-10-03 9:53 ` Anshuman Khandual
2019-10-03 11:19 ` Qian Cai
2019-10-03 11:32 ` Anshuman Khandual
2019-10-03 11:50 ` Qian Cai
2019-10-03 12:02 ` Anshuman Khandual
2019-10-03 12:14 ` Qian Cai
2019-10-04 8:25 ` David Hildenbrand
2020-01-14 8:19 ` Anshuman Khandual
2020-01-14 8:30 ` David Hildenbrand
2020-01-14 9:10 ` Michal Hocko
2020-01-14 10:23 ` Vlastimil Babka
2020-01-14 11:03 ` Anshuman Khandual
2020-01-14 11:32 ` Michal Hocko
2020-01-14 12:04 ` [PATCH] mm, debug: always print flags in dump_page() Vlastimil Babka
2020-01-14 13:35 ` Michal Hocko
2020-01-14 18:22 ` Ralph Campbell [this message]
2019-10-04 10:58 ` [PATCH] mm/page_alloc: Add a reason for reserved pages in has_unmovable_pages() Michal Hocko
2019-10-04 11:44 ` Anshuman Khandual
2019-10-04 12:56 ` Qian Cai
2019-10-04 13:07 ` Michal Hocko
2019-10-04 13:30 ` Qian Cai
2019-10-04 13:38 ` Michal Hocko
2019-10-04 13:56 ` Qian Cai
2019-10-04 14:41 ` Michal Hocko
2019-10-05 21:22 ` Andrew Morton
2019-10-05 22:38 ` Qian Cai
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=958fa7cd-0e88-3387-d4bf-e8bfcfdb256b@nvidia.com \
--to=rcampbell@nvidia.com \
--cc=akpm@linux-foundation.org \
--cc=anshuman.khandual@arm.com \
--cc=cai@lca.pw \
--cc=dan.j.williams@intel.com \
--cc=david@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=mgorman@techsingularity.net \
--cc=mhocko@kernel.org \
--cc=osalvador@suse.de \
--cc=pavel.tatashin@microsoft.com \
--cc=rppt@linux.ibm.com \
--cc=vbabka@suse.cz \
/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).