kernel: backport page fragment API changes from 4.10+ to 4.9

mt76 now relies on this API

Signed-off-by: Felix Fietkau <nbd@nbd.name>
This commit is contained in:
Felix Fietkau 2018-07-14 11:38:28 +02:00
parent 888a15ff83
commit 18533ff415
3 changed files with 291 additions and 0 deletions

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@ -0,0 +1,75 @@
From: Alexander Duyck <alexander.h.duyck@intel.com>
Date: Wed, 14 Dec 2016 15:05:26 -0800
Subject: [PATCH] mm: add support for releasing multiple instances of a page
Add a function that allows us to batch free a page that has multiple
references outstanding. Specifically this function can be used to drop
a page being used in the page frag alloc cache. With this drivers can
make use of functionality similar to the page frag alloc cache without
having to do any workarounds for the fact that there is no function that
frees multiple references.
Link: http://lkml.kernel.org/r/20161110113606.76501.70752.stgit@ahduyck-blue-test.jf.intel.com
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Hans-Christian Noren Egtvedt <egtvedt@samfundet.no>
Cc: Helge Deller <deller@gmx.de>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Keguang Zhang <keguang.zhang@gmail.com>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Rich Felker <dalias@libc.org>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Steven Miao <realmz6@gmail.com>
Cc: Tobias Klauser <tklauser@distanz.ch>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
--- a/include/linux/gfp.h
+++ b/include/linux/gfp.h
@@ -506,6 +506,8 @@ extern void free_hot_cold_page(struct pa
extern void free_hot_cold_page_list(struct list_head *list, bool cold);
struct page_frag_cache;
+extern void __page_frag_drain(struct page *page, unsigned int order,
+ unsigned int count);
extern void *__alloc_page_frag(struct page_frag_cache *nc,
unsigned int fragsz, gfp_t gfp_mask);
extern void __free_page_frag(void *addr);
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -3946,6 +3946,20 @@ static struct page *__page_frag_refill(s
return page;
}
+void __page_frag_drain(struct page *page, unsigned int order,
+ unsigned int count)
+{
+ VM_BUG_ON_PAGE(page_ref_count(page) == 0, page);
+
+ if (page_ref_sub_and_test(page, count)) {
+ if (order == 0)
+ free_hot_cold_page(page, false);
+ else
+ __free_pages_ok(page, order);
+ }
+}
+EXPORT_SYMBOL(__page_frag_drain);
+
void *__alloc_page_frag(struct page_frag_cache *nc,
unsigned int fragsz, gfp_t gfp_mask)
{

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From: Alexander Duyck <alexander.h.duyck@intel.com>
Date: Tue, 10 Jan 2017 16:58:06 -0800
Subject: [PATCH] mm: rename __alloc_page_frag to page_frag_alloc and
__free_page_frag to page_frag_free
Patch series "Page fragment updates", v4.
This patch series takes care of a few cleanups for the page fragments
API.
First we do some renames so that things are much more consistent. First
we move the page_frag_ portion of the name to the front of the functions
names. Secondly we split out the cache specific functions from the
other page fragment functions by adding the word "cache" to the name.
Finally I added a bit of documentation that will hopefully help to
explain some of this. I plan to revisit this later as we get things
more ironed out in the near future with the changes planned for the DMA
setup to support eXpress Data Path.
This patch (of 3):
This patch renames the page frag functions to be more consistent with
other APIs. Specifically we place the name page_frag first in the name
and then have either an alloc or free call name that we append as the
suffix. This makes it a bit clearer in terms of naming.
In addition we drop the leading double underscores since we are
technically no longer a backing interface and instead the front end that
is called from the networking APIs.
Link: http://lkml.kernel.org/r/20170104023854.13451.67390.stgit@localhost.localdomain
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
--- a/include/linux/gfp.h
+++ b/include/linux/gfp.h
@@ -508,9 +508,9 @@ extern void free_hot_cold_page_list(stru
struct page_frag_cache;
extern void __page_frag_drain(struct page *page, unsigned int order,
unsigned int count);
-extern void *__alloc_page_frag(struct page_frag_cache *nc,
- unsigned int fragsz, gfp_t gfp_mask);
-extern void __free_page_frag(void *addr);
+extern void *page_frag_alloc(struct page_frag_cache *nc,
+ unsigned int fragsz, gfp_t gfp_mask);
+extern void page_frag_free(void *addr);
#define __free_page(page) __free_pages((page), 0)
#define free_page(addr) free_pages((addr), 0)
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -2471,7 +2471,7 @@ static inline struct sk_buff *netdev_all
static inline void skb_free_frag(void *addr)
{
- __free_page_frag(addr);
+ page_frag_free(addr);
}
void *napi_alloc_frag(unsigned int fragsz);
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -3960,8 +3960,8 @@ void __page_frag_drain(struct page *page
}
EXPORT_SYMBOL(__page_frag_drain);
-void *__alloc_page_frag(struct page_frag_cache *nc,
- unsigned int fragsz, gfp_t gfp_mask)
+void *page_frag_alloc(struct page_frag_cache *nc,
+ unsigned int fragsz, gfp_t gfp_mask)
{
unsigned int size = PAGE_SIZE;
struct page *page;
@@ -4012,19 +4012,19 @@ refill:
return nc->va + offset;
}
-EXPORT_SYMBOL(__alloc_page_frag);
+EXPORT_SYMBOL(page_frag_alloc);
/*
* Frees a page fragment allocated out of either a compound or order 0 page.
*/
-void __free_page_frag(void *addr)
+void page_frag_free(void *addr)
{
struct page *page = virt_to_head_page(addr);
if (unlikely(put_page_testzero(page)))
__free_pages_ok(page, compound_order(page));
}
-EXPORT_SYMBOL(__free_page_frag);
+EXPORT_SYMBOL(page_frag_free);
static void *make_alloc_exact(unsigned long addr, unsigned int order,
size_t size)
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -369,7 +369,7 @@ static void *__netdev_alloc_frag(unsigne
local_irq_save(flags);
nc = this_cpu_ptr(&netdev_alloc_cache);
- data = __alloc_page_frag(nc, fragsz, gfp_mask);
+ data = page_frag_alloc(nc, fragsz, gfp_mask);
local_irq_restore(flags);
return data;
}
@@ -391,7 +391,7 @@ static void *__napi_alloc_frag(unsigned
{
struct napi_alloc_cache *nc = this_cpu_ptr(&napi_alloc_cache);
- return __alloc_page_frag(&nc->page, fragsz, gfp_mask);
+ return page_frag_alloc(&nc->page, fragsz, gfp_mask);
}
void *napi_alloc_frag(unsigned int fragsz)
@@ -441,7 +441,7 @@ struct sk_buff *__netdev_alloc_skb(struc
local_irq_save(flags);
nc = this_cpu_ptr(&netdev_alloc_cache);
- data = __alloc_page_frag(nc, len, gfp_mask);
+ data = page_frag_alloc(nc, len, gfp_mask);
pfmemalloc = nc->pfmemalloc;
local_irq_restore(flags);
@@ -505,7 +505,7 @@ struct sk_buff *__napi_alloc_skb(struct
if (sk_memalloc_socks())
gfp_mask |= __GFP_MEMALLOC;
- data = __alloc_page_frag(&nc->page, len, gfp_mask);
+ data = page_frag_alloc(&nc->page, len, gfp_mask);
if (unlikely(!data))
return NULL;

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From: Alexander Duyck <alexander.h.duyck@intel.com>
Date: Tue, 10 Jan 2017 16:58:09 -0800
Subject: [PATCH] mm: rename __page_frag functions to __page_frag_cache, drop
order from drain
This patch does two things.
First it goes through and renames the __page_frag prefixed functions to
__page_frag_cache so that we can be clear that we are draining or
refilling the cache, not the frags themselves.
Second we drop the order parameter from __page_frag_cache_drain since we
don't actually need to pass it since all fragments are either order 0 or
must be a compound page.
Link: http://lkml.kernel.org/r/20170104023954.13451.5678.stgit@localhost.localdomain
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
--- a/include/linux/gfp.h
+++ b/include/linux/gfp.h
@@ -506,8 +506,7 @@ extern void free_hot_cold_page(struct pa
extern void free_hot_cold_page_list(struct list_head *list, bool cold);
struct page_frag_cache;
-extern void __page_frag_drain(struct page *page, unsigned int order,
- unsigned int count);
+extern void __page_frag_cache_drain(struct page *page, unsigned int count);
extern void *page_frag_alloc(struct page_frag_cache *nc,
unsigned int fragsz, gfp_t gfp_mask);
extern void page_frag_free(void *addr);
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -3925,8 +3925,8 @@ EXPORT_SYMBOL(free_pages);
* drivers to provide a backing region of memory for use as either an
* sk_buff->head, or to be used in the "frags" portion of skb_shared_info.
*/
-static struct page *__page_frag_refill(struct page_frag_cache *nc,
- gfp_t gfp_mask)
+static struct page *__page_frag_cache_refill(struct page_frag_cache *nc,
+ gfp_t gfp_mask)
{
struct page *page = NULL;
gfp_t gfp = gfp_mask;
@@ -3946,19 +3946,20 @@ static struct page *__page_frag_refill(s
return page;
}
-void __page_frag_drain(struct page *page, unsigned int order,
- unsigned int count)
+void __page_frag_cache_drain(struct page *page, unsigned int count)
{
VM_BUG_ON_PAGE(page_ref_count(page) == 0, page);
if (page_ref_sub_and_test(page, count)) {
+ unsigned int order = compound_order(page);
+
if (order == 0)
free_hot_cold_page(page, false);
else
__free_pages_ok(page, order);
}
}
-EXPORT_SYMBOL(__page_frag_drain);
+EXPORT_SYMBOL(__page_frag_cache_drain);
void *page_frag_alloc(struct page_frag_cache *nc,
unsigned int fragsz, gfp_t gfp_mask)
@@ -3969,7 +3970,7 @@ void *page_frag_alloc(struct page_frag_c
if (unlikely(!nc->va)) {
refill:
- page = __page_frag_refill(nc, gfp_mask);
+ page = __page_frag_cache_refill(nc, gfp_mask);
if (!page)
return NULL;