From: Alex Sierra <alex.sierra@amd.com>
To: akpm@linux-foundation.org, Felix.Kuehling@amd.com,
linux-mm@kvack.org, rcampbell@nvidia.com,
linux-ext4@vger.kernel.org, linux-xfs@vger.kernel.org
Cc: amd-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org,
hch@lst.de, jgg@nvidia.com, jglisse@redhat.com
Subject: [PATCH v3 1/8] ext4/xfs: add page refcount helper
Date: Sat, 19 Jun 2021 13:31:38 -0500 [thread overview]
Message-ID: <20210619183138.26868-1-alex.sierra@amd.com> (raw)
In-Reply-To: <20210617151705.15367-2-alex.sierra@amd.com>
From: Ralph Campbell <rcampbell@nvidia.com>
There are several places where ZONE_DEVICE struct pages assume a reference
count == 1 means the page is idle and free. Instead of open coding this,
add a helper function to hide this detail.
v3:
[AS]: rename dax_layout_is_idle_page func to dax_page_unused
Signed-off-by: Ralph Campbell <rcampbell@nvidia.com>
Signed-off-by: Alex Sierra <alex.sierra@amd.com>
---
fs/dax.c | 4 ++--
fs/ext4/inode.c | 5 +----
fs/xfs/xfs_file.c | 4 +---
include/linux/dax.h | 10 ++++++++++
4 files changed, 14 insertions(+), 9 deletions(-)
diff --git a/fs/dax.c b/fs/dax.c
index 26d5dcd2d69e..4820bb511d68 100644
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -358,7 +358,7 @@ static void dax_disassociate_entry(void *entry, struct address_space *mapping,
for_each_mapped_pfn(entry, pfn) {
struct page *page = pfn_to_page(pfn);
- WARN_ON_ONCE(trunc && page_ref_count(page) > 1);
+ WARN_ON_ONCE(trunc && !dax_page_unused(page));
WARN_ON_ONCE(page->mapping && page->mapping != mapping);
page->mapping = NULL;
page->index = 0;
@@ -372,7 +372,7 @@ static struct page *dax_busy_page(void *entry)
for_each_mapped_pfn(entry, pfn) {
struct page *page = pfn_to_page(pfn);
- if (page_ref_count(page) > 1)
+ if (!dax_page_unused(page))
return page;
}
return NULL;
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index c173c8405856..9ee00186412f 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -3972,10 +3972,7 @@ int ext4_break_layouts(struct inode *inode)
if (!page)
return 0;
- error = ___wait_var_event(&page->_refcount,
- atomic_read(&page->_refcount) == 1,
- TASK_INTERRUPTIBLE, 0, 0,
- ext4_wait_dax_page(ei));
+ error = dax_wait_page(ei, page, ext4_wait_dax_page);
} while (error == 0);
return error;
diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index 5b0f93f73837..39565fe5f817 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -782,9 +782,7 @@ xfs_break_dax_layouts(
return 0;
*retry = true;
- return ___wait_var_event(&page->_refcount,
- atomic_read(&page->_refcount) == 1, TASK_INTERRUPTIBLE,
- 0, 0, xfs_wait_dax_page(inode));
+ return dax_wait_page(inode, page, xfs_wait_dax_page);
}
int
diff --git a/include/linux/dax.h b/include/linux/dax.h
index b52f084aa643..8b5da1d60dbc 100644
--- a/include/linux/dax.h
+++ b/include/linux/dax.h
@@ -243,6 +243,16 @@ static inline bool dax_mapping(struct address_space *mapping)
return mapping->host && IS_DAX(mapping->host);
}
+static inline bool dax_page_unused(struct page *page)
+{
+ return page_ref_count(page) == 1;
+}
+
+#define dax_wait_page(_inode, _page, _wait_cb) \
+ ___wait_var_event(&(_page)->_refcount, \
+ dax_page_unused(_page), \
+ TASK_INTERRUPTIBLE, 0, 0, _wait_cb(_inode))
+
#ifdef CONFIG_DEV_DAX_HMEM_DEVICES
void hmem_register_device(int target_nid, struct resource *r);
#else
--
2.32.0
next prev parent reply other threads:[~2021-06-19 18:32 UTC|newest]
Thread overview: 26+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-06-17 15:16 [PATCH v3 0/8] Support DEVICE_GENERIC memory in migrate_vma_* Alex Sierra
2021-06-17 15:16 ` [PATCH v3 1/8] ext4/xfs: add page refcount helper Alex Sierra
2021-06-17 16:11 ` Darrick J. Wong
2021-06-17 23:52 ` Dave Chinner
2021-06-19 16:14 ` Sierra Guiza, Alejandro (Alex)
2021-06-19 18:31 ` Alex Sierra [this message]
2021-06-17 15:16 ` [PATCH v3 2/8] mm: remove extra ZONE_DEVICE struct page refcount Alex Sierra
2021-06-17 19:16 ` Ralph Campbell
2021-06-28 16:46 ` Felix Kuehling
2021-06-30 0:23 ` Ralph Campbell
2021-06-17 15:17 ` [PATCH v3 3/8] kernel: resource: lookup_resource as exported symbol Alex Sierra
2021-06-17 15:17 ` [PATCH v3 4/8] drm/amdkfd: add SPM support for SVM Alex Sierra
2021-06-17 15:17 ` [PATCH v3 5/8] drm/amdkfd: generic type as sys mem on migration to ram Alex Sierra
2021-06-17 15:17 ` [PATCH v3 6/8] include/linux/mm.h: helpers to check zone device generic type Alex Sierra
2021-06-17 15:17 ` [PATCH v3 7/8] mm: add generic type support to migrate_vma helpers Alex Sierra
2021-06-17 15:17 ` [PATCH v3 8/8] mm: call pgmap->ops->page_free for DEVICE_GENERIC pages Alex Sierra
2021-06-17 15:56 ` [PATCH v3 0/8] Support DEVICE_GENERIC memory in migrate_vma_* Sierra Guiza, Alejandro (Alex)
2021-06-20 14:14 ` Theodore Ts'o
2021-06-23 21:49 ` Felix Kuehling
2021-06-24 5:30 ` Christoph Hellwig
2021-06-24 15:08 ` Felix Kuehling
2021-07-16 15:07 ` Theodore Y. Ts'o
2021-07-16 22:14 ` Felix Kuehling
2021-07-17 19:54 ` Sierra Guiza, Alejandro (Alex)
2021-07-23 22:46 ` Sierra Guiza, Alejandro (Alex)
2021-07-30 19:02 ` Felix Kuehling
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