linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: "Matthew Wilcox (Oracle)" <willy@infradead.org>
To: akpm@linux-foundation.org
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>,
	linux-fsdevel@vger.kernel.org, linux-mm@kvack.org,
	linux-kernel@vger.kernel.org, Zi Yan <ziy@nvidia.com>,
	Christoph Hellwig <hch@lst.de>, Jeff Layton <jlayton@kernel.org>,
	"Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>,
	Vlastimil Babka <vbabka@suse.cz>,
	William Kucharski <william.kucharski@oracle.com>
Subject: [PATCH v11 08/33] mm: Add folio_get()
Date: Mon, 14 Jun 2021 21:14:10 +0100	[thread overview]
Message-ID: <20210614201435.1379188-9-willy@infradead.org> (raw)
In-Reply-To: <20210614201435.1379188-1-willy@infradead.org>

If we know we have a folio, we can call folio_get() instead
of get_page() and save the overhead of calling compound_head().
No change to generated code.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Jeff Layton <jlayton@kernel.org>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: William Kucharski <william.kucharski@oracle.com>
---
 include/linux/mm.h | 26 +++++++++++++++++---------
 1 file changed, 17 insertions(+), 9 deletions(-)

diff --git a/include/linux/mm.h b/include/linux/mm.h
index b68a55cc8d93..a16ea4e745a7 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1224,18 +1224,26 @@ static inline bool is_pci_p2pdma_page(const struct page *page)
 }
 
 /* 127: arbitrary random number, small enough to assemble well */
-#define page_ref_zero_or_close_to_overflow(page) \
-	((unsigned int) page_ref_count(page) + 127u <= 127u)
+#define folio_ref_zero_or_close_to_overflow(folio) \
+	((unsigned int) folio_ref_count(folio) + 127u <= 127u)
+
+/**
+ * folio_get - Increment the reference count on a folio.
+ * @folio: The folio.
+ *
+ * Context: May be called in any context, as long as you know that
+ * you have a refcount on the folio.  If you do not already have one,
+ * folio_try_get() may be the right interface for you to use.
+ */
+static inline void folio_get(struct folio *folio)
+{
+	VM_BUG_ON_FOLIO(folio_ref_zero_or_close_to_overflow(folio), folio);
+	folio_ref_inc(folio);
+}
 
 static inline void get_page(struct page *page)
 {
-	page = compound_head(page);
-	/*
-	 * Getting a normal page or the head of a compound page
-	 * requires to already have an elevated page->_refcount.
-	 */
-	VM_BUG_ON_PAGE(page_ref_zero_or_close_to_overflow(page), page);
-	page_ref_inc(page);
+	folio_get(page_folio(page));
 }
 
 bool __must_check try_grab_page(struct page *page, unsigned int flags);
-- 
2.30.2


  parent reply	other threads:[~2021-06-14 20:21 UTC|newest]

Thread overview: 68+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-06-14 20:14 [PATCH v11 00/33] Memory folios Matthew Wilcox (Oracle)
2021-06-14 20:14 ` [PATCH v11 01/33] mm: Convert get_page_unless_zero() to return bool Matthew Wilcox (Oracle)
2021-06-15  6:24   ` Christoph Hellwig
2021-06-14 20:14 ` [PATCH v11 02/33] mm: Introduce struct folio Matthew Wilcox (Oracle)
2021-06-14 20:14 ` [PATCH v11 03/33] mm: Add folio_pgdat(), folio_zone() and folio_zonenum() Matthew Wilcox (Oracle)
2021-06-14 20:14 ` [PATCH v11 04/33] mm/vmstat: Add functions to account folio statistics Matthew Wilcox (Oracle)
2021-06-14 20:14 ` [PATCH v11 05/33] mm/debug: Add VM_BUG_ON_FOLIO() and VM_WARN_ON_ONCE_FOLIO() Matthew Wilcox (Oracle)
2021-06-14 20:14 ` [PATCH v11 06/33] mm: Add folio reference count functions Matthew Wilcox (Oracle)
2021-06-14 20:14 ` [PATCH v11 07/33] mm: Add folio_put() Matthew Wilcox (Oracle)
2021-06-14 20:14 ` Matthew Wilcox (Oracle) [this message]
2021-06-14 20:14 ` [PATCH v11 09/33] mm: Add folio_try_get_rcu() Matthew Wilcox (Oracle)
2021-06-15  6:25   ` Christoph Hellwig
2021-06-14 20:14 ` [PATCH v11 10/33] mm: Add folio flag manipulation functions Matthew Wilcox (Oracle)
2021-06-14 20:14 ` [PATCH v11 11/33] mm/lru: Add folio LRU functions Matthew Wilcox (Oracle)
2021-06-15  6:27   ` Christoph Hellwig
2021-06-14 20:14 ` [PATCH v11 12/33] mm: Handle per-folio private data Matthew Wilcox (Oracle)
2021-06-14 20:14 ` [PATCH v11 13/33] mm/filemap: Add folio_index(), folio_file_page() and folio_contains() Matthew Wilcox (Oracle)
2021-06-14 20:14 ` [PATCH v11 14/33] mm/filemap: Add folio_next_index() Matthew Wilcox (Oracle)
2021-06-14 20:14 ` [PATCH v11 15/33] mm/filemap: Add folio_offset() and folio_file_offset() Matthew Wilcox (Oracle)
2021-06-14 20:14 ` [PATCH v11 16/33] mm/util: Add folio_mapping() and folio_file_mapping() Matthew Wilcox (Oracle)
2021-06-14 20:14 ` [PATCH v11 17/33] mm/memcg: Add folio wrappers for various functions Matthew Wilcox (Oracle)
2021-06-14 20:14 ` [PATCH v11 18/33] mm/filemap: Add folio_unlock() Matthew Wilcox (Oracle)
2021-06-14 20:14 ` [PATCH v11 19/33] mm/filemap: Add folio_lock() Matthew Wilcox (Oracle)
2021-06-14 20:14 ` [PATCH v11 20/33] mm/filemap: Add folio_lock_killable() Matthew Wilcox (Oracle)
2021-06-14 20:14 ` [PATCH v11 21/33] mm/filemap: Add __folio_lock_async() Matthew Wilcox (Oracle)
2021-06-14 20:14 ` [PATCH v11 22/33] mm/filemap: Add folio_wait_locked() Matthew Wilcox (Oracle)
2021-06-14 20:14 ` [PATCH v11 23/33] mm/filemap: Add __folio_lock_or_retry() Matthew Wilcox (Oracle)
2021-06-14 20:14 ` [PATCH v11 24/33] mm/swap: Add folio_rotate_reclaimable() Matthew Wilcox (Oracle)
2021-06-15  6:29   ` Christoph Hellwig
2021-06-14 20:14 ` [PATCH v11 25/33] mm/filemap: Add folio_end_writeback() Matthew Wilcox (Oracle)
2021-06-14 20:14 ` [PATCH v11 26/33] mm/writeback: Add folio_wait_writeback() Matthew Wilcox (Oracle)
2021-06-14 20:14 ` [PATCH v11 27/33] mm/writeback: Add folio_wait_stable() Matthew Wilcox (Oracle)
2021-06-14 20:14 ` [PATCH v11 28/33] mm/filemap: Add folio_wait_bit() Matthew Wilcox (Oracle)
2021-06-14 20:14 ` [PATCH v11 29/33] mm/filemap: Add folio_wake_bit() Matthew Wilcox (Oracle)
2021-06-14 20:14 ` [PATCH v11 30/33] mm/filemap: Convert page wait queues to be folios Matthew Wilcox (Oracle)
2021-06-14 20:14 ` [PATCH v11 31/33] mm/filemap: Add folio private_2 functions Matthew Wilcox (Oracle)
2021-06-14 20:14 ` [PATCH v11 32/33] fs/netfs: Add folio fscache functions Matthew Wilcox (Oracle)
2021-06-14 20:14 ` [PATCH v11 33/33] mm: Add folio_mapped() Matthew Wilcox (Oracle)
2021-06-15  6:31   ` Christoph Hellwig
2021-06-16  9:16 ` [PATCH v11 32/33] fs/netfs: Add folio fscache functions David Howells
2021-06-16  9:19 ` [PATCH v11 01/33] mm: Convert get_page_unless_zero() to return bool David Howells
2021-06-16  9:31 ` [PATCH v11 02/33] mm: Introduce struct folio David Howells
2021-06-16  9:36 ` [PATCH v11 04/33] mm/vmstat: Add functions to account folio statistics David Howells
2021-06-16  9:54 ` [PATCH v11 05/33] mm/debug: Add VM_BUG_ON_FOLIO() and VM_WARN_ON_ONCE_FOLIO() David Howells
2021-06-16  9:55 ` [PATCH v11 06/33] mm: Add folio reference count functions David Howells
2021-06-16  9:55 ` [PATCH v11 07/33] mm: Add folio_put() David Howells
2021-06-16  9:56 ` [PATCH v11 08/33] mm: Add folio_get() David Howells
2021-06-16  9:58 ` [PATCH v11 10/33] mm: Add folio flag manipulation functions David Howells
2021-06-16 10:00 ` [PATCH v11 11/33] mm/lru: Add folio LRU functions David Howells
2021-06-16 10:03 ` [PATCH v11 13/33] mm/filemap: Add folio_index(), folio_file_page() and folio_contains() David Howells
2021-06-16 11:38   ` Matthew Wilcox
2021-06-16 10:04 ` [PATCH v11 14/33] mm/filemap: Add folio_next_index() David Howells
2021-06-16 10:05 ` [PATCH v11 15/33] mm/filemap: Add folio_offset() and folio_file_offset() David Howells
2021-06-16 10:10 ` [PATCH v11 16/33] mm/util: Add folio_mapping() and folio_file_mapping() David Howells
2021-06-16 10:13 ` [PATCH v11 18/33] mm/filemap: Add folio_unlock() David Howells
2021-06-16 10:17 ` [PATCH v11 19/33] mm/filemap: Add folio_lock() David Howells
2021-06-16 10:22 ` [PATCH v11 21/33] mm/filemap: Add __folio_lock_async() David Howells
2021-06-16 10:23 ` [PATCH v11 22/33] mm/filemap: Add folio_wait_locked() David Howells
2021-06-16 10:27 ` [PATCH v11 24/33] mm/swap: Add folio_rotate_reclaimable() David Howells
2021-06-16 11:46   ` Matthew Wilcox
2021-06-16 10:30 ` [PATCH v11 26/33] mm/writeback: Add folio_wait_writeback() David Howells
2021-06-16 11:55   ` Matthew Wilcox
2021-06-16 10:32 ` [PATCH v11 27/33] mm/writeback: Add folio_wait_stable() David Howells
2021-06-16 10:33 ` [PATCH v11 28/33] mm/filemap: Add folio_wait_bit() David Howells
2021-06-16 10:35 ` [PATCH v11 30/33] mm/filemap: Convert page wait queues to be folios David Howells
2021-06-16 10:37 ` [PATCH v11 33/33] mm: Add folio_mapped() David Howells
2021-06-16 10:41 ` [PATCH v11 02/33] mm: Introduce struct folio David Howells
2021-06-16 10:54 ` [PATCH v11 00/33] Memory folios David Howells

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=20210614201435.1379188-9-willy@infradead.org \
    --to=willy@infradead.org \
    --cc=akpm@linux-foundation.org \
    --cc=hch@lst.de \
    --cc=jlayton@kernel.org \
    --cc=kirill.shutemov@linux.intel.com \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=vbabka@suse.cz \
    --cc=william.kucharski@oracle.com \
    --cc=ziy@nvidia.com \
    --subject='Re: [PATCH v11 08/33] mm: Add folio_get()' \
    /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

This is a public inbox, see mirroring instructions
on how to clone and mirror all data and code used for this inbox