Re: [RFC PATCH 2/3] mm: add find_alloc_contig_pages() interface

2018-02-13 Thread Mike Rapoport 
On Mon, Feb 12, 2018 at 02:20:55PM -0800, Mike Kravetz wrote:
> find_alloc_contig_pages() is a new interface that attempts to locate
> and allocate a contiguous range of pages.  It is provided as a more
> convenient interface to the existing alloc_contig_range() interface
> which is used by CMA, memory hotplug and gigantic huge pages.
> 
> When attempting to allocate a range of pages, migration is employed
> if possible.  There is no guarantee that the routine will succeed.
> So, the user must be prepared for failure and have a fall back plan.
> 
> Signed-off-by: Mike Kravetz 
> ---
>  include/linux/gfp.h | 12 
>  mm/page_alloc.c | 89 
> +++--
>  2 files changed, 99 insertions(+), 2 deletions(-)
> 
> diff --git a/include/linux/gfp.h b/include/linux/gfp.h
> index 1a4582b44d32..456979022956 100644
> --- a/include/linux/gfp.h
> +++ b/include/linux/gfp.h
> @@ -573,6 +573,18 @@ static inline bool pm_suspended_storage(void)
>  extern int alloc_contig_range(unsigned long start, unsigned long end,
> unsigned migratetype, gfp_t gfp_mask);
>  extern void free_contig_range(unsigned long pfn, unsigned nr_pages);
> +extern struct page *find_alloc_contig_pages(unsigned int order, gfp_t gfp,
> + int nid, nodemask_t *nodemask);
> +extern void free_contig_pages(struct page *page, unsigned nr_pages);
> +#else
> +static inline page *find_alloc_contig_pages(unsigned int order, gfp_t gfp,
> + int nid, nodemask_t *nodemask)
> +{
> + return NULL;
> +}
> +static void free_contig_pages(struct page *page, unsigned nr_pages)
> +{
> +}
>  #endif
> 
>  #ifdef CONFIG_CMA
> diff --git a/mm/page_alloc.c b/mm/page_alloc.c
> index 064458f317bf..0a5a547acdbf 100644
> --- a/mm/page_alloc.c
> +++ b/mm/page_alloc.c
> @@ -67,6 +67,7 @@
>  #include 
>  #include 
>  #include 
> +#include 
> 
>  #include 
>  #include 
> @@ -1873,9 +1874,13 @@ static __always_inline struct page 
> *__rmqueue_cma_fallback(struct zone *zone,
>  {
>   return __rmqueue_smallest(zone, order, MIGRATE_CMA);
>  }
> +#define contig_alloc_migratetype_ok(migratetype) \
> + ((migratetype) == MIGRATE_CMA || (migratetype) == MIGRATE_MOVABLE)
>  #else
>  static inline struct page *__rmqueue_cma_fallback(struct zone *zone,
>   unsigned int order) { return NULL; }
> +#define contig_alloc_migratetype_ok(migratetype) \
> + ((migratetype) == MIGRATE_MOVABLE)
>  #endif
> 
>  /*
> @@ -7633,6 +7638,9 @@ int alloc_contig_range(unsigned long start, unsigned 
> long end,
>   };
>   INIT_LIST_HEAD();
> 
> + if (!contig_alloc_migratetype_ok(migratetype))
> + return -EINVAL;
> +
>   /*
>* What we do here is we mark all pageblocks in range as
>* MIGRATE_ISOLATE.  Because pageblock and max order pages may
> @@ -7723,8 +7731,9 @@ int alloc_contig_range(unsigned long start, unsigned 
> long end,
> 
>   /* Make sure the range is really isolated. */
>   if (test_pages_isolated(outer_start, end, false)) {
> - pr_info_ratelimited("%s: [%lx, %lx) PFNs busy\n",
> - __func__, outer_start, end);
> + if (!(migratetype == MIGRATE_MOVABLE)) /* only print for CMA */
> + pr_info_ratelimited("%s: [%lx, %lx) PFNs busy\n",
> + __func__, outer_start, end);
>   ret = -EBUSY;
>   goto done;
>   }
> @@ -7760,6 +7769,82 @@ void free_contig_range(unsigned long pfn, unsigned 
> nr_pages)
>   }
>   WARN(count != 0, "%d pages are still in use!\n", count);
>  }
> +
> +static bool contig_pfn_range_valid(struct zone *z, unsigned long start_pfn,
> + unsigned long nr_pages)
> +{
> + unsigned long i, end_pfn = start_pfn + nr_pages;
> + struct page *page;
> +
> + for (i = start_pfn; i < end_pfn; i++) {
> + if (!pfn_valid(i))
> + return false;
> +
> + page = pfn_to_page(i);
> +
> + if (page_zone(page) != z)
> + return false;
> +
> + }
> +
> + return true;
> +}
> +
> +/**
> + * find_alloc_contig_pages() -- attempt to find and allocate a contiguous
> + *   range of pages
> + * @order:   number of pages
> + * @gfp: gfp mask used to limit search as well as during compaction
> + * @nid: target node
> + * @nodemask:mask of other possible nodes
> + *
> + * Returns pointer to 'order' pages on success, or NULL if not successful.

Please s/Returns/Return:/ and move the return value description to the end
of the comment block.

> + *
> + * Pages can be freed with a call to free_contig_pages(), or by manually
> + * calling __free_page() for each page allocated.
> + */
> +struct page *find_alloc_contig_pages(unsigned int order, gfp_t gfp,
> +

Re: [RFC PATCH 2/3] mm: add find_alloc_contig_pages() interface

2018-02-13 Thread Mike Rapoport 
On Mon, Feb 12, 2018 at 02:20:55PM -0800, Mike Kravetz wrote:
> find_alloc_contig_pages() is a new interface that attempts to locate
> and allocate a contiguous range of pages.  It is provided as a more
> convenient interface to the existing alloc_contig_range() interface
> which is used by CMA, memory hotplug and gigantic huge pages.
> 
> When attempting to allocate a range of pages, migration is employed
> if possible.  There is no guarantee that the routine will succeed.
> So, the user must be prepared for failure and have a fall back plan.
> 
> Signed-off-by: Mike Kravetz 
> ---
>  include/linux/gfp.h | 12 
>  mm/page_alloc.c | 89 
> +++--
>  2 files changed, 99 insertions(+), 2 deletions(-)
> 
> diff --git a/include/linux/gfp.h b/include/linux/gfp.h
> index 1a4582b44d32..456979022956 100644
> --- a/include/linux/gfp.h
> +++ b/include/linux/gfp.h
> @@ -573,6 +573,18 @@ static inline bool pm_suspended_storage(void)
>  extern int alloc_contig_range(unsigned long start, unsigned long end,
> unsigned migratetype, gfp_t gfp_mask);
>  extern void free_contig_range(unsigned long pfn, unsigned nr_pages);
> +extern struct page *find_alloc_contig_pages(unsigned int order, gfp_t gfp,
> + int nid, nodemask_t *nodemask);
> +extern void free_contig_pages(struct page *page, unsigned nr_pages);
> +#else
> +static inline page *find_alloc_contig_pages(unsigned int order, gfp_t gfp,
> + int nid, nodemask_t *nodemask)
> +{
> + return NULL;
> +}
> +static void free_contig_pages(struct page *page, unsigned nr_pages)
> +{
> +}
>  #endif
> 
>  #ifdef CONFIG_CMA
> diff --git a/mm/page_alloc.c b/mm/page_alloc.c
> index 064458f317bf..0a5a547acdbf 100644
> --- a/mm/page_alloc.c
> +++ b/mm/page_alloc.c
> @@ -67,6 +67,7 @@
>  #include 
>  #include 
>  #include 
> +#include 
> 
>  #include 
>  #include 
> @@ -1873,9 +1874,13 @@ static __always_inline struct page 
> *__rmqueue_cma_fallback(struct zone *zone,
>  {
>   return __rmqueue_smallest(zone, order, MIGRATE_CMA);
>  }
> +#define contig_alloc_migratetype_ok(migratetype) \
> + ((migratetype) == MIGRATE_CMA || (migratetype) == MIGRATE_MOVABLE)
>  #else
>  static inline struct page *__rmqueue_cma_fallback(struct zone *zone,
>   unsigned int order) { return NULL; }
> +#define contig_alloc_migratetype_ok(migratetype) \
> + ((migratetype) == MIGRATE_MOVABLE)
>  #endif
> 
>  /*
> @@ -7633,6 +7638,9 @@ int alloc_contig_range(unsigned long start, unsigned 
> long end,
>   };
>   INIT_LIST_HEAD();
> 
> + if (!contig_alloc_migratetype_ok(migratetype))
> + return -EINVAL;
> +
>   /*
>* What we do here is we mark all pageblocks in range as
>* MIGRATE_ISOLATE.  Because pageblock and max order pages may
> @@ -7723,8 +7731,9 @@ int alloc_contig_range(unsigned long start, unsigned 
> long end,
> 
>   /* Make sure the range is really isolated. */
>   if (test_pages_isolated(outer_start, end, false)) {
> - pr_info_ratelimited("%s: [%lx, %lx) PFNs busy\n",
> - __func__, outer_start, end);
> + if (!(migratetype == MIGRATE_MOVABLE)) /* only print for CMA */
> + pr_info_ratelimited("%s: [%lx, %lx) PFNs busy\n",
> + __func__, outer_start, end);
>   ret = -EBUSY;
>   goto done;
>   }
> @@ -7760,6 +7769,82 @@ void free_contig_range(unsigned long pfn, unsigned 
> nr_pages)
>   }
>   WARN(count != 0, "%d pages are still in use!\n", count);
>  }
> +
> +static bool contig_pfn_range_valid(struct zone *z, unsigned long start_pfn,
> + unsigned long nr_pages)
> +{
> + unsigned long i, end_pfn = start_pfn + nr_pages;
> + struct page *page;
> +
> + for (i = start_pfn; i < end_pfn; i++) {
> + if (!pfn_valid(i))
> + return false;
> +
> + page = pfn_to_page(i);
> +
> + if (page_zone(page) != z)
> + return false;
> +
> + }
> +
> + return true;
> +}
> +
> +/**
> + * find_alloc_contig_pages() -- attempt to find and allocate a contiguous
> + *   range of pages
> + * @order:   number of pages
> + * @gfp: gfp mask used to limit search as well as during compaction
> + * @nid: target node
> + * @nodemask:mask of other possible nodes
> + *
> + * Returns pointer to 'order' pages on success, or NULL if not successful.

Please s/Returns/Return:/ and move the return value description to the end
of the comment block.

> + *
> + * Pages can be freed with a call to free_contig_pages(), or by manually
> + * calling __free_page() for each page allocated.
> + */
> +struct page *find_alloc_contig_pages(unsigned int order, gfp_t gfp,
> +

[RFC PATCH 2/3] mm: add find_alloc_contig_pages() interface

2018-02-12 Thread Mike Kravetz 
find_alloc_contig_pages() is a new interface that attempts to locate
and allocate a contiguous range of pages.  It is provided as a more
convenient interface to the existing alloc_contig_range() interface
which is used by CMA, memory hotplug and gigantic huge pages.

When attempting to allocate a range of pages, migration is employed
if possible.  There is no guarantee that the routine will succeed.
So, the user must be prepared for failure and have a fall back plan.

Signed-off-by: Mike Kravetz 
---
 include/linux/gfp.h | 12 
 mm/page_alloc.c | 89 +++--
 2 files changed, 99 insertions(+), 2 deletions(-)

diff --git a/include/linux/gfp.h b/include/linux/gfp.h
index 1a4582b44d32..456979022956 100644
--- a/include/linux/gfp.h
+++ b/include/linux/gfp.h
@@ -573,6 +573,18 @@ static inline bool pm_suspended_storage(void)
 extern int alloc_contig_range(unsigned long start, unsigned long end,
  unsigned migratetype, gfp_t gfp_mask);
 extern void free_contig_range(unsigned long pfn, unsigned nr_pages);
+extern struct page *find_alloc_contig_pages(unsigned int order, gfp_t gfp,
+   int nid, nodemask_t *nodemask);
+extern void free_contig_pages(struct page *page, unsigned nr_pages);
+#else
+static inline page *find_alloc_contig_pages(unsigned int order, gfp_t gfp,
+   int nid, nodemask_t *nodemask)
+{
+   return NULL;
+}
+static void free_contig_pages(struct page *page, unsigned nr_pages)
+{
+}
 #endif
 
 #ifdef CONFIG_CMA
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 064458f317bf..0a5a547acdbf 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -67,6 +67,7 @@
 #include 
 #include 
 #include 
+#include 
 
 #include 
 #include 
@@ -1873,9 +1874,13 @@ static __always_inline struct page 
*__rmqueue_cma_fallback(struct zone *zone,
 {
return __rmqueue_smallest(zone, order, MIGRATE_CMA);
 }
+#define contig_alloc_migratetype_ok(migratetype) \
+   ((migratetype) == MIGRATE_CMA || (migratetype) == MIGRATE_MOVABLE)
 #else
 static inline struct page *__rmqueue_cma_fallback(struct zone *zone,
unsigned int order) { return NULL; }
+#define contig_alloc_migratetype_ok(migratetype) \
+   ((migratetype) == MIGRATE_MOVABLE)
 #endif
 
 /*
@@ -7633,6 +7638,9 @@ int alloc_contig_range(unsigned long start, unsigned long 
end,
};
INIT_LIST_HEAD();
 
+   if (!contig_alloc_migratetype_ok(migratetype))
+   return -EINVAL;
+
/*
 * What we do here is we mark all pageblocks in range as
 * MIGRATE_ISOLATE.  Because pageblock and max order pages may
@@ -7723,8 +7731,9 @@ int alloc_contig_range(unsigned long start, unsigned long 
end,
 
/* Make sure the range is really isolated. */
if (test_pages_isolated(outer_start, end, false)) {
-   pr_info_ratelimited("%s: [%lx, %lx) PFNs busy\n",
-   __func__, outer_start, end);
+   if (!(migratetype == MIGRATE_MOVABLE)) /* only print for CMA */
+   pr_info_ratelimited("%s: [%lx, %lx) PFNs busy\n",
+   __func__, outer_start, end);
ret = -EBUSY;
goto done;
}
@@ -7760,6 +7769,82 @@ void free_contig_range(unsigned long pfn, unsigned 
nr_pages)
}
WARN(count != 0, "%d pages are still in use!\n", count);
 }
+
+static bool contig_pfn_range_valid(struct zone *z, unsigned long start_pfn,
+   unsigned long nr_pages)
+{
+   unsigned long i, end_pfn = start_pfn + nr_pages;
+   struct page *page;
+
+   for (i = start_pfn; i < end_pfn; i++) {
+   if (!pfn_valid(i))
+   return false;
+
+   page = pfn_to_page(i);
+
+   if (page_zone(page) != z)
+   return false;
+
+   }
+
+   return true;
+}
+
+/**
+ * find_alloc_contig_pages() -- attempt to find and allocate a contiguous
+ * range of pages
+ * @order: number of pages
+ * @gfp:   gfp mask used to limit search as well as during compaction
+ * @nid:   target node
+ * @nodemask:  mask of other possible nodes
+ *
+ * Returns pointer to 'order' pages on success, or NULL if not successful.
+ *
+ * Pages can be freed with a call to free_contig_pages(), or by manually
+ * calling __free_page() for each page allocated.
+ */
+struct page *find_alloc_contig_pages(unsigned int order, gfp_t gfp,
+   int nid, nodemask_t *nodemask)
+{
+   unsigned long pfn, nr_pages, flags;
+   struct page *ret_page = NULL;
+   struct zonelist *zonelist;
+   struct zoneref *z;
+   struct zone *zone;
+   int rc;
+
+   nr_pages = 1 << order;
+   zonelist = node_zonelist(nid, gfp);
+

[RFC PATCH 2/3] mm: add find_alloc_contig_pages() interface

2018-02-12 Thread Mike Kravetz 
find_alloc_contig_pages() is a new interface that attempts to locate
and allocate a contiguous range of pages.  It is provided as a more
convenient interface to the existing alloc_contig_range() interface
which is used by CMA, memory hotplug and gigantic huge pages.

When attempting to allocate a range of pages, migration is employed
if possible.  There is no guarantee that the routine will succeed.
So, the user must be prepared for failure and have a fall back plan.

Signed-off-by: Mike Kravetz 
---
 include/linux/gfp.h | 12 
 mm/page_alloc.c | 89 +++--
 2 files changed, 99 insertions(+), 2 deletions(-)

diff --git a/include/linux/gfp.h b/include/linux/gfp.h
index 1a4582b44d32..456979022956 100644
--- a/include/linux/gfp.h
+++ b/include/linux/gfp.h
@@ -573,6 +573,18 @@ static inline bool pm_suspended_storage(void)
 extern int alloc_contig_range(unsigned long start, unsigned long end,
  unsigned migratetype, gfp_t gfp_mask);
 extern void free_contig_range(unsigned long pfn, unsigned nr_pages);
+extern struct page *find_alloc_contig_pages(unsigned int order, gfp_t gfp,
+   int nid, nodemask_t *nodemask);
+extern void free_contig_pages(struct page *page, unsigned nr_pages);
+#else
+static inline page *find_alloc_contig_pages(unsigned int order, gfp_t gfp,
+   int nid, nodemask_t *nodemask)
+{
+   return NULL;
+}
+static void free_contig_pages(struct page *page, unsigned nr_pages)
+{
+}
 #endif
 
 #ifdef CONFIG_CMA
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 064458f317bf..0a5a547acdbf 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -67,6 +67,7 @@
 #include 
 #include 
 #include 
+#include 
 
 #include 
 #include 
@@ -1873,9 +1874,13 @@ static __always_inline struct page 
*__rmqueue_cma_fallback(struct zone *zone,
 {
return __rmqueue_smallest(zone, order, MIGRATE_CMA);
 }
+#define contig_alloc_migratetype_ok(migratetype) \
+   ((migratetype) == MIGRATE_CMA || (migratetype) == MIGRATE_MOVABLE)
 #else
 static inline struct page *__rmqueue_cma_fallback(struct zone *zone,
unsigned int order) { return NULL; }
+#define contig_alloc_migratetype_ok(migratetype) \
+   ((migratetype) == MIGRATE_MOVABLE)
 #endif
 
 /*
@@ -7633,6 +7638,9 @@ int alloc_contig_range(unsigned long start, unsigned long 
end,
};
INIT_LIST_HEAD();
 
+   if (!contig_alloc_migratetype_ok(migratetype))
+   return -EINVAL;
+
/*
 * What we do here is we mark all pageblocks in range as
 * MIGRATE_ISOLATE.  Because pageblock and max order pages may
@@ -7723,8 +7731,9 @@ int alloc_contig_range(unsigned long start, unsigned long 
end,
 
/* Make sure the range is really isolated. */
if (test_pages_isolated(outer_start, end, false)) {
-   pr_info_ratelimited("%s: [%lx, %lx) PFNs busy\n",
-   __func__, outer_start, end);
+   if (!(migratetype == MIGRATE_MOVABLE)) /* only print for CMA */
+   pr_info_ratelimited("%s: [%lx, %lx) PFNs busy\n",
+   __func__, outer_start, end);
ret = -EBUSY;
goto done;
}
@@ -7760,6 +7769,82 @@ void free_contig_range(unsigned long pfn, unsigned 
nr_pages)
}
WARN(count != 0, "%d pages are still in use!\n", count);
 }
+
+static bool contig_pfn_range_valid(struct zone *z, unsigned long start_pfn,
+   unsigned long nr_pages)
+{
+   unsigned long i, end_pfn = start_pfn + nr_pages;
+   struct page *page;
+
+   for (i = start_pfn; i < end_pfn; i++) {
+   if (!pfn_valid(i))
+   return false;
+
+   page = pfn_to_page(i);
+
+   if (page_zone(page) != z)
+   return false;
+
+   }
+
+   return true;
+}
+
+/**
+ * find_alloc_contig_pages() -- attempt to find and allocate a contiguous
+ * range of pages
+ * @order: number of pages
+ * @gfp:   gfp mask used to limit search as well as during compaction
+ * @nid:   target node
+ * @nodemask:  mask of other possible nodes
+ *
+ * Returns pointer to 'order' pages on success, or NULL if not successful.
+ *
+ * Pages can be freed with a call to free_contig_pages(), or by manually
+ * calling __free_page() for each page allocated.
+ */
+struct page *find_alloc_contig_pages(unsigned int order, gfp_t gfp,
+   int nid, nodemask_t *nodemask)
+{
+   unsigned long pfn, nr_pages, flags;
+   struct page *ret_page = NULL;
+   struct zonelist *zonelist;
+   struct zoneref *z;
+   struct zone *zone;
+   int rc;
+
+   nr_pages = 1 << order;
+   zonelist = node_zonelist(nid, gfp);
+