From: Christoph Hellwig <hch@lst.de>
To: Dan Williams <dan.j.williams@intel.com>
Cc: "Jérôme Glisse" <jglisse@redhat.com>,
"Logan Gunthorpe" <logang@deltatee.com>,
"Michal Hocko" <mhocko@kernel.org>,
linux-nvdimm@lists.01.org, linuxppc-dev@lists.ozlabs.org,
x86@kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: [PATCH 11/17] mm: move get_dev_pagemap out of line
Date: Fri, 29 Dec 2017 08:54:00 +0100 [thread overview]
Message-ID: <20171229075406.1936-12-hch@lst.de> (raw)
In-Reply-To: <20171229075406.1936-1-hch@lst.de>
This is a pretty big function, which should be out of line in general,
and a no-op stub if CONFIG_ZONE_DEVICD? is not set.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
---
include/linux/memremap.h | 39 ++++-----------------------------------
kernel/memremap.c | 36 ++++++++++++++++++++++++++++++++++--
2 files changed, 38 insertions(+), 37 deletions(-)
diff --git a/include/linux/memremap.h b/include/linux/memremap.h
index d5a6736d9737..26e8aaba27d5 100644
--- a/include/linux/memremap.h
+++ b/include/linux/memremap.h
@@ -133,7 +133,8 @@ struct dev_pagemap {
#ifdef CONFIG_ZONE_DEVICE
void *devm_memremap_pages(struct device *dev, struct resource *res,
struct percpu_ref *ref, struct vmem_altmap *altmap);
-struct dev_pagemap *find_dev_pagemap(resource_size_t phys);
+struct dev_pagemap *get_dev_pagemap(unsigned long pfn,
+ struct dev_pagemap *pgmap);
unsigned long vmem_altmap_offset(struct vmem_altmap *altmap);
void vmem_altmap_free(struct vmem_altmap *altmap, unsigned long nr_pfns);
@@ -153,7 +154,8 @@ static inline void *devm_memremap_pages(struct device *dev,
return ERR_PTR(-ENXIO);
}
-static inline struct dev_pagemap *find_dev_pagemap(resource_size_t phys)
+static inline struct dev_pagemap *get_dev_pagemap(unsigned long pfn,
+ struct dev_pagemap *pgmap)
{
return NULL;
}
@@ -183,39 +185,6 @@ static inline bool is_device_public_page(const struct page *page)
}
#endif /* CONFIG_DEVICE_PRIVATE || CONFIG_DEVICE_PUBLIC */
-/**
- * get_dev_pagemap() - take a new live reference on the dev_pagemap for @pfn
- * @pfn: page frame number to lookup page_map
- * @pgmap: optional known pgmap that already has a reference
- *
- * @pgmap allows the overhead of a lookup to be bypassed when @pfn lands in the
- * same mapping.
- */
-static inline struct dev_pagemap *get_dev_pagemap(unsigned long pfn,
- struct dev_pagemap *pgmap)
-{
- const struct resource *res = pgmap ? pgmap->res : NULL;
- resource_size_t phys = PFN_PHYS(pfn);
-
- /*
- * In the cached case we're already holding a live reference so
- * we can simply do a blind increment
- */
- if (res && phys >= res->start && phys <= res->end) {
- percpu_ref_get(pgmap->ref);
- return pgmap;
- }
-
- /* fall back to slow path lookup */
- rcu_read_lock();
- pgmap = find_dev_pagemap(phys);
- if (pgmap && !percpu_ref_tryget_live(pgmap->ref))
- pgmap = NULL;
- rcu_read_unlock();
-
- return pgmap;
-}
-
static inline void put_dev_pagemap(struct dev_pagemap *pgmap)
{
if (pgmap)
diff --git a/kernel/memremap.c b/kernel/memremap.c
index 64b12c806cc5..3df6cd4ffb40 100644
--- a/kernel/memremap.c
+++ b/kernel/memremap.c
@@ -314,7 +314,7 @@ static void devm_memremap_pages_release(struct device *dev, void *data)
}
/* assumes rcu_read_lock() held at entry */
-struct dev_pagemap *find_dev_pagemap(resource_size_t phys)
+static struct dev_pagemap *find_dev_pagemap(resource_size_t phys)
{
struct page_map *page_map;
@@ -501,8 +501,40 @@ struct vmem_altmap *to_vmem_altmap(unsigned long memmap_start)
return pgmap ? pgmap->altmap : NULL;
}
-#endif /* CONFIG_ZONE_DEVICE */
+/**
+ * get_dev_pagemap() - take a new live reference on the dev_pagemap for @pfn
+ * @pfn: page frame number to lookup page_map
+ * @pgmap: optional known pgmap that already has a reference
+ *
+ * @pgmap allows the overhead of a lookup to be bypassed when @pfn lands in the
+ * same mapping.
+ */
+struct dev_pagemap *get_dev_pagemap(unsigned long pfn,
+ struct dev_pagemap *pgmap)
+{
+ const struct resource *res = pgmap ? pgmap->res : NULL;
+ resource_size_t phys = PFN_PHYS(pfn);
+
+ /*
+ * In the cached case we're already holding a live reference so
+ * we can simply do a blind increment
+ */
+ if (res && phys >= res->start && phys <= res->end) {
+ percpu_ref_get(pgmap->ref);
+ return pgmap;
+ }
+
+ /* fall back to slow path lookup */
+ rcu_read_lock();
+ pgmap = find_dev_pagemap(phys);
+ if (pgmap && !percpu_ref_tryget_live(pgmap->ref))
+ pgmap = NULL;
+ rcu_read_unlock();
+
+ return pgmap;
+}
+#endif /* CONFIG_ZONE_DEVICE */
#if IS_ENABLED(CONFIG_DEVICE_PRIVATE) || IS_ENABLED(CONFIG_DEVICE_PUBLIC)
void put_zone_device_private_or_public_page(struct page *page)
--
2.14.2
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next prev parent reply other threads:[~2017-12-29 7:55 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-12-29 7:53 revamp vmem_altmap / dev_pagemap handling V3 Christoph Hellwig
2017-12-29 7:53 ` [PATCH 01/17] memremap: provide stubs for vmem_altmap_offset and vmem_altmap_free Christoph Hellwig
2017-12-29 7:53 ` [PATCH 02/17] mm: don't export arch_add_memory Christoph Hellwig
2017-12-29 7:53 ` [PATCH 03/17] mm: don't export __add_pages Christoph Hellwig
2017-12-29 7:53 ` [PATCH 04/17] mm: pass the vmem_altmap to arch_add_memory and __add_pages Christoph Hellwig
2017-12-29 7:53 ` [PATCH 05/17] mm: pass the vmem_altmap to vmemmap_populate Christoph Hellwig
2017-12-29 7:53 ` [PATCH 06/17] mm: pass the vmem_altmap to arch_remove_memory and __remove_pages Christoph Hellwig
2017-12-29 7:53 ` [PATCH 07/17] mm: pass the vmem_altmap to vmemmap_free Christoph Hellwig
2017-12-29 7:53 ` [PATCH 08/17] mm: pass the vmem_altmap to memmap_init_zone Christoph Hellwig
2017-12-29 7:53 ` [PATCH 09/17] mm: split altmap memory map allocation from normal case Christoph Hellwig
2017-12-29 7:53 ` [PATCH 10/17] mm: merge vmem_altmap_alloc into altmap_alloc_block_buf Christoph Hellwig
2017-12-29 7:54 ` Christoph Hellwig [this message]
2017-12-29 7:54 ` [PATCH 12/17] mm: optimize dev_pagemap reference counting around get_dev_pagemap Christoph Hellwig
2017-12-29 7:54 ` [PATCH 13/17] memremap: remove to_vmem_altmap Christoph Hellwig
2017-12-29 7:54 ` [PATCH 14/17] memremap: simplify duplicate region handling in devm_memremap_pages Christoph Hellwig
2017-12-29 7:54 ` [PATCH 15/17] memremap: drop private struct page_map Christoph Hellwig
2017-12-29 7:54 ` [PATCH 16/17] memremap: change devm_memremap_pages interface to use struct dev_pagemap Christoph Hellwig
2017-12-29 7:54 ` [PATCH 17/17] memremap: merge find_dev_pagemap into get_dev_pagemap Christoph Hellwig
2018-01-08 11:26 ` revamp vmem_altmap / dev_pagemap handling V3 Christoph Hellwig
2018-01-08 19:44 ` Dan Williams
2018-01-08 20:25 ` Michal Hocko
2018-01-08 21:27 ` Dan Williams
2018-01-08 21:50 ` Michal Hocko
2018-01-15 8:51 ` Christoph Hellwig
2018-01-11 16:27 ` Jerome Glisse
-- strict thread matches above, loose matches on Subject: below --
2017-12-15 14:09 revamp vmem_altmap / dev_pagemap handling V2 Christoph Hellwig
2017-12-15 14:09 ` [PATCH 11/17] mm: move get_dev_pagemap out of line Christoph Hellwig
2017-12-17 17:26 ` Dan Williams
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