From: Hugh Dickins <hughd@google•com>
To: Hugh Dickins <hughd@google•com>
Cc: Miaohe Lin <linmiaohe@huawei•com>,
David Hildenbrand <david@redhat•com>,
Peter Zijlstra <peterz@infradead•org>,
Yang Shi <shy828301@gmail•com>, Peter Xu <peterx@redhat•com>,
Song Liu <song@kernel•org>,
sparclinux@vger•kernel.org,
Alexander Gordeev <agordeev@linux•ibm.com>,
Claudio Imbrenda <imbrenda@linux•ibm.com>,
Will Deacon <will@kernel•org>,
linux-s390@vger•kernel.org, Yu Zhao <yuzhao@google•com>,
Ira Weiny <ira.weiny@intel•com>,
Alistair Popple <apopple@nvidia•com>,
Russell King <linux@armlinux•org.uk>,
Matthew Wilcox <willy@infradead•org>,
Steven Price <steven.price@arm•com>,
Christoph Hellwig <hch@infradead•org>,
Jason Gunthorpe <jgg@ziepe•ca>,
"Aneesh Kumar K.V" <aneesh.kumar@linux•ibm.com>,
Axel Rasmussen <axelrasmussen@google•com>,
Christian Borntraeger <borntraeger@linux•ibm.com>,
Thomas Hellstrom <thomas.hellstrom@linux•intel.com>,
Ralph Campbell <rcampbell@nvidia•com>,
Pasha Tatashin <pasha.tatashin@soleen•com>,
Anshuman Khandual <anshuman.khandual@arm•com>,
Heiko Ca rstens <hca@linux•ibm.com>,
Qi Zheng <zhengqi.arch@bytedance•com>,
Suren Baghdasaryan <surenb@google•com>,
linux-arm-kernel@lists•infradead.org,
SeongJae Park <sj@kernel•org>, Jann Horn <jannh@google•com>,
linux-mm@kvack•org, linuxppc-dev@lists•ozlabs.org,
"Kirill A. Shutemov" <kirill.shutemov@linux•intel.com>,
Naoya Horiguchi <naoya.horiguchi@nec•com>,
linux-kernel@vger•kernel.org, Minchan Kim <minchan@kernel•org>,
Mike Rapoport <rppt@kernel•org>,
Andrew Morton <akpm@linux-foundation•org>,
Mel Gorman <mgorman@techsingularity•net>,
"David S. Miller" <davem@davemloft•net>,
Zack Rusin <zackr@vmware•com>,
Mike Kravetz <mike.kravetz@oracle•com>
Subject: Re: [PATCH 06/12] sparc: add pte_free_defer() for pgtables sharing page
Date: Mon, 5 Jun 2023 20:46:10 -0700 (PDT) [thread overview]
Message-ID: <ba73bd57-4bcf-e555-2a9e-a21f2e4214b@google.com> (raw)
In-Reply-To: <f8d84fb8-eb9-6649-7137-715c6010468c@google.com>
On Sun, 28 May 2023, Hugh Dickins wrote:
> Add sparc-specific pte_free_defer(), to call pte_free() via call_rcu().
> pte_free_defer() will be called inside khugepaged's retract_page_tables()
> loop, where allocating extra memory cannot be relied upon. This precedes
> the generic version to avoid build breakage from incompatible pgtable_t.
sparc32 supports pagetables sharing a page, but does not support THP;
sparc64 supports THP, but does not support pagetables sharing a page.
So the sparc-specific pte_free_defer() is as simple as the generic one,
except for converting between pte_t *pgtable_t and struct page *.
The patch should be fine as posted (except its title is misleading).
>
> Signed-off-by: Hugh Dickins <hughd@google•com>
> ---
> arch/sparc/include/asm/pgalloc_64.h | 4 ++++
> arch/sparc/mm/init_64.c | 16 ++++++++++++++++
> 2 files changed, 20 insertions(+)
>
> diff --git a/arch/sparc/include/asm/pgalloc_64.h b/arch/sparc/include/asm/pgalloc_64.h
> index 7b5561d17ab1..caa7632be4c2 100644
> --- a/arch/sparc/include/asm/pgalloc_64.h
> +++ b/arch/sparc/include/asm/pgalloc_64.h
> @@ -65,6 +65,10 @@ pgtable_t pte_alloc_one(struct mm_struct *mm);
> void pte_free_kernel(struct mm_struct *mm, pte_t *pte);
> void pte_free(struct mm_struct *mm, pgtable_t ptepage);
>
> +/* arch use pte_free_defer() implementation in arch/sparc/mm/init_64.c */
> +#define pte_free_defer pte_free_defer
> +void pte_free_defer(struct mm_struct *mm, pgtable_t pgtable);
> +
> #define pmd_populate_kernel(MM, PMD, PTE) pmd_set(MM, PMD, PTE)
> #define pmd_populate(MM, PMD, PTE) pmd_set(MM, PMD, PTE)
>
> diff --git a/arch/sparc/mm/init_64.c b/arch/sparc/mm/init_64.c
> index 04f9db0c3111..b7c6aa085ef6 100644
> --- a/arch/sparc/mm/init_64.c
> +++ b/arch/sparc/mm/init_64.c
> @@ -2930,6 +2930,22 @@ void pgtable_free(void *table, bool is_page)
> }
>
> #ifdef CONFIG_TRANSPARENT_HUGEPAGE
> +static void pte_free_now(struct rcu_head *head)
> +{
> + struct page *page;
> +
> + page = container_of(head, struct page, rcu_head);
> + __pte_free((pgtable_t)page_to_virt(page));
> +}
> +
> +void pte_free_defer(struct mm_struct *mm, pgtable_t pgtable)
> +{
> + struct page *page;
> +
> + page = virt_to_page(pgtable);
> + call_rcu(&page->rcu_head, pte_free_now);
> +}
> +
> void update_mmu_cache_pmd(struct vm_area_struct *vma, unsigned long addr,
> pmd_t *pmd)
> {
> --
> 2.35.3
>
>
next prev parent reply other threads:[~2023-06-06 3:47 UTC|newest]
Thread overview: 50+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-05-29 6:11 [PATCH 00/12] mm: free retracted page table by RCU Hugh Dickins
2023-05-29 6:14 ` [PATCH 01/12] mm/pgtable: add rcu_read_lock() and rcu_read_unlock()s Hugh Dickins
2023-05-31 17:06 ` Jann Horn
2023-06-02 2:50 ` Hugh Dickins
2023-06-02 14:21 ` Jann Horn
2023-05-29 6:16 ` [PATCH 02/12] mm/pgtable: add PAE safety to __pte_offset_map() Hugh Dickins
2023-05-29 13:56 ` Matthew Wilcox
[not found] ` <ZHeg3oRljRn6wlLX@ziepe.ca>
2023-06-02 5:35 ` Hugh Dickins
2023-05-29 6:17 ` [PATCH 03/12] arm: adjust_pte() use pte_offset_map_nolock() Hugh Dickins
2023-05-29 6:18 ` [PATCH 04/12] powerpc: assert_pte_locked() " Hugh Dickins
2023-05-29 6:20 ` [PATCH 05/12] powerpc: add pte_free_defer() for pgtables sharing page Hugh Dickins
2023-05-29 14:02 ` Matthew Wilcox
2023-05-29 14:36 ` Hugh Dickins
2023-06-01 13:57 ` Gerald Schaefer
2023-06-02 6:38 ` Hugh Dickins
2023-06-02 14:20 ` Jason Gunthorpe
2023-06-06 3:40 ` Hugh Dickins
2023-06-06 18:23 ` Jason Gunthorpe
2023-06-06 19:03 ` Peter Xu
2023-06-06 19:08 ` Jason Gunthorpe
2023-06-07 3:49 ` Hugh Dickins
2023-05-29 6:21 ` [PATCH 06/12] sparc: " Hugh Dickins
2023-06-06 3:46 ` Hugh Dickins [this message]
2023-05-29 6:22 ` [PATCH 07/12] s390: add pte_free_defer(), with use of mmdrop_async() Hugh Dickins
2023-06-06 5:11 ` Hugh Dickins
2023-06-06 18:39 ` Jason Gunthorpe
2023-06-08 2:46 ` Hugh Dickins
2023-06-06 19:40 ` Gerald Schaefer
2023-06-08 3:35 ` Hugh Dickins
2023-06-08 13:58 ` Jason Gunthorpe
2023-06-08 15:47 ` Gerald Schaefer
2023-05-29 6:23 ` [PATCH 08/12] mm/pgtable: add pte_free_defer() for pgtable as page Hugh Dickins
2023-06-01 13:31 ` Jann Horn
[not found] ` <ZHekpAKJ05cr/GLl@ziepe.ca>
2023-06-02 6:03 ` Hugh Dickins
2023-06-02 12:15 ` Jason Gunthorpe
2023-05-29 6:25 ` [PATCH 09/12] mm/khugepaged: retract_page_tables() without mmap or vma lock Hugh Dickins
2023-05-29 23:26 ` Peter Xu
2023-05-31 0:38 ` Hugh Dickins
2023-05-31 15:34 ` Jann Horn
[not found] ` <ZHe0A079X9B8jWlH@x1n>
2023-05-31 22:18 ` Jann Horn
2023-06-01 14:06 ` Jason Gunthorpe
2023-06-06 6:18 ` Hugh Dickins
2023-05-29 6:26 ` [PATCH 10/12] mm/khugepaged: collapse_pte_mapped_thp() with mmap_read_lock() Hugh Dickins
2023-05-31 17:25 ` Jann Horn
2023-06-02 5:11 ` Hugh Dickins
2023-05-29 6:28 ` [PATCH 11/12] mm/khugepaged: delete khugepaged_collapse_pte_mapped_thps() Hugh Dickins
2023-05-29 6:30 ` [PATCH 12/12] mm: delete mmap_write_trylock() and vma_try_start_write() Hugh Dickins
[not found] ` <CAG48ez0pCqfRdVSnJz7EKtNvMR65=zJgVB-72nTdrNuhtJNX2Q@mail.gmail.com>
2023-06-02 4:37 ` [PATCH 00/12] mm: free retracted page table by RCU Hugh Dickins
2023-06-02 15:26 ` Jann Horn
2023-06-06 6:28 ` Hugh Dickins
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=ba73bd57-4bcf-e555-2a9e-a21f2e4214b@google.com \
--to=hughd@google$(echo .)com \
--cc=agordeev@linux$(echo .)ibm.com \
--cc=akpm@linux-foundation$(echo .)org \
--cc=aneesh.kumar@linux$(echo .)ibm.com \
--cc=anshuman.khandual@arm$(echo .)com \
--cc=apopple@nvidia$(echo .)com \
--cc=axelrasmussen@google$(echo .)com \
--cc=borntraeger@linux$(echo .)ibm.com \
--cc=davem@davemloft$(echo .)net \
--cc=david@redhat$(echo .)com \
--cc=hca@linux$(echo .)ibm.com \
--cc=hch@infradead$(echo .)org \
--cc=imbrenda@linux$(echo .)ibm.com \
--cc=ira.weiny@intel$(echo .)com \
--cc=jannh@google$(echo .)com \
--cc=jgg@ziepe$(echo .)ca \
--cc=kirill.shutemov@linux$(echo .)intel.com \
--cc=linmiaohe@huawei$(echo .)com \
--cc=linux-arm-kernel@lists$(echo .)infradead.org \
--cc=linux-kernel@vger$(echo .)kernel.org \
--cc=linux-mm@kvack$(echo .)org \
--cc=linux-s390@vger$(echo .)kernel.org \
--cc=linux@armlinux$(echo .)org.uk \
--cc=linuxppc-dev@lists$(echo .)ozlabs.org \
--cc=mgorman@techsingularity$(echo .)net \
--cc=mike.kravetz@oracle$(echo .)com \
--cc=minchan@kernel$(echo .)org \
--cc=naoya.horiguchi@nec$(echo .)com \
--cc=pasha.tatashin@soleen$(echo .)com \
--cc=peterx@redhat$(echo .)com \
--cc=peterz@infradead$(echo .)org \
--cc=rcampbell@nvidia$(echo .)com \
--cc=rppt@kernel$(echo .)org \
--cc=shy828301@gmail$(echo .)com \
--cc=sj@kernel$(echo .)org \
--cc=song@kernel$(echo .)org \
--cc=sparclinux@vger$(echo .)kernel.org \
--cc=steven.price@arm$(echo .)com \
--cc=surenb@google$(echo .)com \
--cc=thomas.hellstrom@linux$(echo .)intel.com \
--cc=will@kernel$(echo .)org \
--cc=willy@infradead$(echo .)org \
--cc=yuzhao@google$(echo .)com \
--cc=zackr@vmware$(echo .)com \
--cc=zhengqi.arch@bytedance$(echo .)com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
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