linux-fsdevel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Oscar Salvador <osalvador@suse.de>
To: Muchun Song <songmuchun@bytedance.com>
Cc: corbet@lwn.net, mike.kravetz@oracle.com, tglx@linutronix.de,
	mingo@redhat.com, bp@alien8.de, x86@kernel.org, hpa@zytor.com,
	dave.hansen@linux.intel.com, luto@kernel.org,
	peterz@infradead.org, viro@zeniv.linux.org.uk,
	akpm@linux-foundation.org, paulmck@kernel.org,
	mchehab+huawei@kernel.org, pawan.kumar.gupta@linux.intel.com,
	rdunlap@infradead.org, oneukum@suse.com,
	anshuman.khandual@arm.com, jroedel@suse.de,
	almasrymina@google.com, rientjes@google.com, willy@infradead.org,
	mhocko@suse.com, duanxiongchun@bytedance.com,
	linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-mm@kvack.org, linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH v3 08/21] mm/vmemmap: Initialize page table lock for vmemmap
Date: Mon, 9 Nov 2020 19:11:04 +0100	[thread overview]
Message-ID: <20201109181104.GC17356@linux> (raw)
In-Reply-To: <20201108141113.65450-9-songmuchun@bytedance.com>

On Sun, Nov 08, 2020 at 10:11:00PM +0800, Muchun Song wrote:
> In the register_page_bootmem_memmap, the slab allocator is not ready
> yet. So when ALLOC_SPLIT_PTLOCKS, we use init_mm.page_table_lock.
> otherwise we use per page table lock(page->ptl). In the later patch,
> we will use the vmemmap page table lock to guard the splitting of
> the vmemmap huge PMD.

I am not sure about this one.
Grabbing init_mm's pagetable lock for specific hugetlb operations does not
seem like a good idea, and we do not know how contented is that one.

I think a better fit would be to find another hook to initialize
page_table_lock at a later stage.
Anyway, we do not need till we are going to perform an operation
on the range, right?

Unless I am missing something, this should be doable in hugetlb_init.

hugetlb_init is part from a init_call that gets called during do_initcalls.
At this time, slab is fully operative.

start_kernel
 kmem_cache_init_late
 kmem_cache_init_late
 ...
 arch_call_rest_init
  rest_init
   kernel_init_freeable
    do_basic_setup
     do_initcalls
      hugetlb_init

-- 
Oscar Salvador
SUSE L3

  reply	other threads:[~2020-11-09 18:11 UTC|newest]

Thread overview: 54+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-11-08 14:10 [PATCH v3 00/21] Free some vmemmap pages of hugetlb page Muchun Song
2020-11-08 14:10 ` [PATCH v3 01/21] mm/memory_hotplug: Move bootmem info registration API to bootmem_info.c Muchun Song
2020-11-08 14:10 ` [PATCH v3 02/21] mm/memory_hotplug: Move {get,put}_page_bootmem() " Muchun Song
2020-11-08 14:10 ` [PATCH v3 03/21] mm/hugetlb: Introduce a new config HUGETLB_PAGE_FREE_VMEMMAP Muchun Song
2020-11-09 13:52   ` Oscar Salvador
2020-11-09 14:20     ` [External] " Muchun Song
2020-11-10 19:31     ` Mike Kravetz
2020-11-10 19:50       ` Matthew Wilcox
2020-11-10 20:30         ` Mike Kravetz
2020-11-17 15:35         ` [External] " Muchun Song
2020-11-11  3:28       ` Muchun Song
2020-11-08 14:10 ` [PATCH v3 04/21] mm/hugetlb: Introduce nr_free_vmemmap_pages in the struct hstate Muchun Song
2020-11-09 16:48   ` Oscar Salvador
2020-11-10  2:42     ` [External] " Muchun Song
2020-11-10 19:38       ` Mike Kravetz
2020-11-11  3:22         ` Muchun Song
2020-11-08 14:10 ` [PATCH v3 05/21] mm/hugetlb: Introduce pgtable allocation/freeing helpers Muchun Song
2020-11-09 17:21   ` Oscar Salvador
2020-11-10  3:49     ` [External] " Muchun Song
2020-11-10  5:42       ` Oscar Salvador
2020-11-10  6:08         ` Muchun Song
2020-11-10  6:33           ` Oscar Salvador
2020-11-10  7:10             ` Muchun Song
2020-11-11  0:47   ` Mike Kravetz
2020-11-11  3:41     ` [External] " Muchun Song
2020-11-13  0:35       ` Mike Kravetz
2020-11-13  1:02         ` Mike Kravetz
2020-11-13  4:18         ` Muchun Song
2020-11-08 14:10 ` [PATCH v3 06/21] mm/bootmem_info: Introduce {free,prepare}_vmemmap_page() Muchun Song
2020-11-08 14:10 ` [PATCH v3 07/21] mm/bootmem_info: Combine bootmem info and type into page->freelist Muchun Song
2020-11-08 14:11 ` [PATCH v3 08/21] mm/vmemmap: Initialize page table lock for vmemmap Muchun Song
2020-11-09 18:11   ` Oscar Salvador [this message]
2020-11-10  5:17     ` [External] " Muchun Song
2020-11-08 14:11 ` [PATCH v3 09/21] mm/hugetlb: Free the vmemmap pages associated with each hugetlb page Muchun Song
2020-11-09 18:51   ` Oscar Salvador
2020-11-10  6:40     ` [External] " Muchun Song
2020-11-10  9:48       ` Oscar Salvador
2020-11-10 10:47         ` Muchun Song
2020-11-10 13:52           ` Oscar Salvador
2020-11-10 14:00             ` Muchun Song
2020-11-08 14:11 ` [PATCH v3 10/21] mm/hugetlb: Defer freeing of hugetlb pages Muchun Song
2020-11-08 14:11 ` [PATCH v3 11/21] mm/hugetlb: Allocate the vmemmap pages associated with each hugetlb page Muchun Song
2020-11-08 14:11 ` [PATCH v3 12/21] mm/hugetlb: Introduce remap_huge_page_pmd_vmemmap helper Muchun Song
2020-11-08 14:11 ` [PATCH v3 13/21] mm/hugetlb: Use PG_slab to indicate split pmd Muchun Song
2020-11-08 14:11 ` [PATCH v3 14/21] mm/hugetlb: Support freeing vmemmap pages of gigantic page Muchun Song
2020-11-08 14:11 ` [PATCH v3 15/21] mm/hugetlb: Add a BUILD_BUG_ON to check if struct page size is a power of two Muchun Song
2020-11-08 14:11 ` [PATCH v3 16/21] mm/hugetlb: Set the PageHWPoison to the raw error page Muchun Song
2020-11-08 14:11 ` [PATCH v3 17/21] mm/hugetlb: Flush work when dissolving hugetlb page Muchun Song
2020-11-08 14:11 ` [PATCH v3 18/21] mm/hugetlb: Add a kernel parameter hugetlb_free_vmemmap Muchun Song
2020-11-08 14:11 ` [PATCH v3 19/21] mm/hugetlb: Merge pte to huge pmd only for gigantic page Muchun Song
2020-11-08 14:11 ` [PATCH v3 20/21] mm/hugetlb: Gather discrete indexes of tail page Muchun Song
2020-11-08 14:11 ` [PATCH v3 21/21] mm/hugetlb: Add BUILD_BUG_ON to catch invalid usage of tail struct page Muchun Song
2020-11-10 19:23 ` [PATCH v3 00/21] Free some vmemmap pages of hugetlb page Mike Kravetz
2020-11-11  3:21   ` [External] " Muchun Song

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=20201109181104.GC17356@linux \
    --to=osalvador@suse.de \
    --cc=akpm@linux-foundation.org \
    --cc=almasrymina@google.com \
    --cc=anshuman.khandual@arm.com \
    --cc=bp@alien8.de \
    --cc=corbet@lwn.net \
    --cc=dave.hansen@linux.intel.com \
    --cc=duanxiongchun@bytedance.com \
    --cc=hpa@zytor.com \
    --cc=jroedel@suse.de \
    --cc=linux-doc@vger.kernel.org \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=luto@kernel.org \
    --cc=mchehab+huawei@kernel.org \
    --cc=mhocko@suse.com \
    --cc=mike.kravetz@oracle.com \
    --cc=mingo@redhat.com \
    --cc=oneukum@suse.com \
    --cc=paulmck@kernel.org \
    --cc=pawan.kumar.gupta@linux.intel.com \
    --cc=peterz@infradead.org \
    --cc=rdunlap@infradead.org \
    --cc=rientjes@google.com \
    --cc=songmuchun@bytedance.com \
    --cc=tglx@linutronix.de \
    --cc=viro@zeniv.linux.org.uk \
    --cc=willy@infradead.org \
    --cc=x86@kernel.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).