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, Vlastimil Babka <vbabka@suse.cz>,
William Kucharski <william.kucharski@oracle.com>,
Christoph Hellwig <hch@lst.de>,
David Howells <dhowells@redhat.com>
Subject: [PATCH v12 33/33] mm: Add folio_mapped()
Date: Tue, 22 Jun 2021 12:41:18 +0100 [thread overview]
Message-ID: <20210622114118.3388190-34-willy@infradead.org> (raw)
In-Reply-To: <20210622114118.3388190-1-willy@infradead.org>
This function is the equivalent of page_mapped(). It is slightly
shorter as we do not need to handle the PageTail() case. Reimplement
page_mapped() as a wrapper around folio_mapped(). folio_mapped()
is 13 bytes smaller than page_mapped(), but the page_mapped() wrapper
is 30 bytes, for a net increase of 17 bytes of text.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: William Kucharski <william.kucharski@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Howells <dhowells@redhat.com>
---
include/linux/mm.h | 1 +
include/linux/mm_types.h | 6 ++++++
mm/folio-compat.c | 6 ++++++
mm/util.c | 29 ++++++++++++++++-------------
4 files changed, 29 insertions(+), 13 deletions(-)
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 28ef6bff3316..9b7030d1899f 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1768,6 +1768,7 @@ static inline pgoff_t page_index(struct page *page)
}
bool page_mapped(struct page *page);
+bool folio_mapped(struct folio *folio);
/*
* Return true only if the page has been allocated with
diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index 943854268986..0a0d7e3d069f 100644
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -284,6 +284,12 @@ FOLIO_MATCH(memcg_data, memcg_data);
#endif
#undef FOLIO_MATCH
+static inline atomic_t *folio_mapcount_ptr(struct folio *folio)
+{
+ struct page *tail = &folio->page + 1;
+ return &tail->compound_mapcount;
+}
+
static inline atomic_t *compound_mapcount_ptr(struct page *page)
{
return &page[1].compound_mapcount;
diff --git a/mm/folio-compat.c b/mm/folio-compat.c
index 3c83f03b80d7..7044fcc8a8aa 100644
--- a/mm/folio-compat.c
+++ b/mm/folio-compat.c
@@ -35,3 +35,9 @@ void wait_for_stable_page(struct page *page)
return folio_wait_stable(page_folio(page));
}
EXPORT_SYMBOL_GPL(wait_for_stable_page);
+
+bool page_mapped(struct page *page)
+{
+ return folio_mapped(page_folio(page));
+}
+EXPORT_SYMBOL(page_mapped);
diff --git a/mm/util.c b/mm/util.c
index afd99591cb81..a8766e7f1b7f 100644
--- a/mm/util.c
+++ b/mm/util.c
@@ -652,28 +652,31 @@ void *page_rmapping(struct page *page)
return __page_rmapping(page);
}
-/*
- * Return true if this page is mapped into pagetables.
- * For compound page it returns true if any subpage of compound page is mapped.
+/**
+ * folio_mapped - Is this folio mapped into userspace?
+ * @folio: The folio.
+ *
+ * Return: True if any page in this folio is referenced by user page tables.
*/
-bool page_mapped(struct page *page)
+bool folio_mapped(struct folio *folio)
{
- int i;
+ int i, nr;
- if (likely(!PageCompound(page)))
- return atomic_read(&page->_mapcount) >= 0;
- page = compound_head(page);
- if (atomic_read(compound_mapcount_ptr(page)) >= 0)
+ if (folio_single(folio))
+ return atomic_read(&folio->_mapcount) >= 0;
+ if (atomic_read(folio_mapcount_ptr(folio)) >= 0)
return true;
- if (PageHuge(page))
+ if (folio_hugetlb(folio))
return false;
- for (i = 0; i < compound_nr(page); i++) {
- if (atomic_read(&page[i]._mapcount) >= 0)
+
+ nr = folio_nr_pages(folio);
+ for (i = 0; i < nr; i++) {
+ if (atomic_read(&folio_page(folio, i)->_mapcount) >= 0)
return true;
}
return false;
}
-EXPORT_SYMBOL(page_mapped);
+EXPORT_SYMBOL(folio_mapped);
struct anon_vma *page_anon_vma(struct page *page)
{
--
2.30.2
next prev parent reply other threads:[~2021-06-22 12:12 UTC|newest]
Thread overview: 42+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-06-22 11:40 [PATCH v12 00/33] Memory folios Matthew Wilcox (Oracle)
2021-06-22 11:40 ` [PATCH v12 01/33] mm: Convert get_page_unless_zero() to return bool Matthew Wilcox (Oracle)
2021-06-23 7:46 ` Christoph Hellwig
2021-06-28 12:35 ` Kirill A. Shutemov
2021-06-22 11:40 ` [PATCH v12 02/33] mm: Introduce struct folio Matthew Wilcox (Oracle)
2021-06-22 11:40 ` [PATCH v12 03/33] mm: Add folio_pgdat(), folio_zone() and folio_zonenum() Matthew Wilcox (Oracle)
2021-06-22 11:40 ` [PATCH v12 04/33] mm/vmstat: Add functions to account folio statistics Matthew Wilcox (Oracle)
2021-06-22 11:40 ` [PATCH v12 05/33] mm/debug: Add VM_BUG_ON_FOLIO() and VM_WARN_ON_ONCE_FOLIO() Matthew Wilcox (Oracle)
2021-06-22 11:40 ` [PATCH v12 06/33] mm: Add folio reference count functions Matthew Wilcox (Oracle)
2021-06-22 11:40 ` [PATCH v12 07/33] mm: Add folio_put() Matthew Wilcox (Oracle)
2021-06-22 11:40 ` [PATCH v12 08/33] mm: Add folio_get() Matthew Wilcox (Oracle)
2021-06-22 11:40 ` [PATCH v12 09/33] mm: Add folio_try_get_rcu() Matthew Wilcox (Oracle)
2021-06-28 12:38 ` Kirill A. Shutemov
2021-06-22 11:40 ` [PATCH v12 10/33] mm: Add folio flag manipulation functions Matthew Wilcox (Oracle)
2021-06-22 11:40 ` [PATCH v12 11/33] mm/lru: Add folio LRU functions Matthew Wilcox (Oracle)
2021-06-28 12:40 ` Kirill A. Shutemov
2021-06-22 11:40 ` [PATCH v12 12/33] mm: Handle per-folio private data Matthew Wilcox (Oracle)
2021-06-22 11:40 ` [PATCH v12 13/33] mm/filemap: Add folio_index(), folio_file_page() and folio_contains() Matthew Wilcox (Oracle)
2021-06-22 11:40 ` [PATCH v12 14/33] mm/filemap: Add folio_next_index() Matthew Wilcox (Oracle)
2021-06-22 11:41 ` [PATCH v12 15/33] mm/filemap: Add folio_pos() and folio_file_pos() Matthew Wilcox (Oracle)
2021-06-22 11:41 ` [PATCH v12 16/33] mm/util: Add folio_mapping() and folio_file_mapping() Matthew Wilcox (Oracle)
2021-06-22 11:41 ` [PATCH v12 17/33] mm/memcg: Add folio wrappers for various functions Matthew Wilcox (Oracle)
2021-06-22 11:41 ` [PATCH v12 18/33] mm/filemap: Add folio_unlock() Matthew Wilcox (Oracle)
2021-06-22 11:41 ` [PATCH v12 19/33] mm/filemap: Add folio_lock() Matthew Wilcox (Oracle)
2021-06-22 11:41 ` [PATCH v12 20/33] mm/filemap: Add folio_lock_killable() Matthew Wilcox (Oracle)
2021-06-22 11:41 ` [PATCH v12 21/33] mm/filemap: Add __folio_lock_async() Matthew Wilcox (Oracle)
2021-06-22 11:41 ` [PATCH v12 22/33] mm/filemap: Add folio_wait_locked() Matthew Wilcox (Oracle)
2021-06-22 11:41 ` [PATCH v12 23/33] mm/filemap: Add __folio_lock_or_retry() Matthew Wilcox (Oracle)
2021-06-22 11:41 ` [PATCH v12 24/33] mm/swap: Add folio_rotate_reclaimable() Matthew Wilcox (Oracle)
2021-06-28 12:46 ` Kirill A. Shutemov
2021-06-22 11:41 ` [PATCH v12 25/33] mm/filemap: Add folio_end_writeback() Matthew Wilcox (Oracle)
2021-06-22 11:41 ` [PATCH v12 26/33] mm/writeback: Add folio_wait_writeback() Matthew Wilcox (Oracle)
2021-06-22 11:41 ` [PATCH v12 27/33] mm/writeback: Add folio_wait_stable() Matthew Wilcox (Oracle)
2021-06-22 11:41 ` [PATCH v12 28/33] mm/filemap: Add folio_wait_bit() Matthew Wilcox (Oracle)
2021-06-22 11:41 ` [PATCH v12 29/33] mm/filemap: Add folio_wake_bit() Matthew Wilcox (Oracle)
2021-06-22 11:41 ` [PATCH v12 30/33] mm/filemap: Convert page wait queues to be folios Matthew Wilcox (Oracle)
2021-06-22 11:41 ` [PATCH v12 31/33] mm/filemap: Add folio private_2 functions Matthew Wilcox (Oracle)
2021-06-28 12:47 ` Kirill A. Shutemov
2021-06-22 11:41 ` [PATCH v12 32/33] fs/netfs: Add folio fscache functions Matthew Wilcox (Oracle)
2021-06-28 12:49 ` Kirill A. Shutemov
2021-06-22 11:41 ` Matthew Wilcox (Oracle) [this message]
2021-06-28 12:51 ` [PATCH v12 33/33] mm: Add folio_mapped() Kirill A. Shutemov
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=20210622114118.3388190-34-willy@infradead.org \
--to=willy@infradead.org \
--cc=akpm@linux-foundation.org \
--cc=dhowells@redhat.com \
--cc=hch@lst.de \
--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 \
/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).