Groups > linux.kernel > #1375691 > unrolled thread

[PATCH 0/19] get rid of superfluous __GFP_REPORT

Started by	Michal Hocko <mhocko@kernel.org>
First post	2016-04-11 13:10 +0200
Last post	2016-04-13 15:40 +0200
Articles	20 on this page of 32 — 8 participants

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  [PATCH 0/19] get rid of superfluous __GFP_REPORT Michal Hocko <mhocko@kernel.org> - 2016-04-11 13:10 +0200
    [PATCH 15/19] tile: get rid of superfluous __GFP_REPEAT Michal Hocko <mhocko@kernel.org> - 2016-04-11 13:10 +0200
    [PATCH 18/19] crypto: get rid of superfluous __GFP_REPEAT Michal Hocko <mhocko@kernel.org> - 2016-04-11 13:10 +0200
      Re: [PATCH 18/19] crypto: get rid of superfluous __GFP_REPEAT Herbert Xu <herbert@gondor.apana.org.au> - 2016-04-14 08:30 +0200
        Re: [PATCH 18/19] crypto: get rid of superfluous __GFP_REPEAT Michal Hocko <mhocko@kernel.org> - 2016-04-14 09:10 +0200
          Re: [PATCH 18/19] crypto: get rid of superfluous __GFP_REPEAT Herbert Xu <herbert@gondor.apana.org.au> - 2016-04-14 10:20 +0200
      [PATCH resend] crypto: get rid of superfluous __GFP_REPEAT Michal Hocko <mhocko@kernel.org> - 2016-04-14 11:00 +0200
        Re: [PATCH resend] crypto: get rid of superfluous __GFP_REPEAT Herbert Xu <herbert@gondor.apana.org.au> - 2016-04-15 16:40 +0200
    [PATCH 09/19] parisc: get rid of superfluous __GFP_REPEAT Michal Hocko <mhocko@kernel.org> - 2016-04-11 13:10 +0200
    [PATCH 16/19] unicore32: get rid of superfluous __GFP_REPEAT Michal Hocko <mhocko@kernel.org> - 2016-04-11 13:10 +0200
    [PATCH 08/19] nios2: get rid of superfluous __GFP_REPEAT Michal Hocko <mhocko@kernel.org> - 2016-04-11 13:20 +0200
    [PATCH 01/19] tree wide: get rid of __GFP_REPEAT for order-0 allocations part I Michal Hocko <mhocko@kernel.org> - 2016-04-11 13:20 +0200
      Re: [PATCH 01/19] tree wide: get rid of __GFP_REPEAT for order-0  allocations part I David Rientjes <rientjes@google.com> - 2016-04-14 22:00 +0200
        Re: [PATCH 01/19] tree wide: get rid of __GFP_REPEAT for order-0  allocations part I Michal Hocko <mhocko@kernel.org> - 2016-04-15 09:50 +0200
    [PATCH 06/19] arc: get rid of superfluous __GFP_REPEAT Michal Hocko <mhocko@kernel.org> - 2016-04-11 13:20 +0200
      Re: [PATCH 06/19] arc: get rid of superfluous __GFP_REPEAT Vineet Gupta <Vineet.Gupta1@synopsys.com> - 2016-04-11 16:30 +0200
    [PATCH 11/19] powerpc: get rid of superfluous __GFP_REPEAT Michal Hocko <mhocko@kernel.org> - 2016-04-11 13:20 +0200
    [PATCH 10/19] score: get rid of superfluous __GFP_REPEAT Michal Hocko <mhocko@kernel.org> - 2016-04-11 13:20 +0200
    [PATCH 07/19] mips: get rid of superfluous __GFP_REPEAT Michal Hocko <mhocko@kernel.org> - 2016-04-11 13:20 +0200
    [PATCH 19/19] jbd2: get rid of superfluous __GFP_REPEAT Michal Hocko <mhocko@kernel.org> - 2016-04-11 13:20 +0200
    [PATCH 13/19] s390: get rid of superfluous __GFP_REPEAT Michal Hocko <mhocko@kernel.org> - 2016-04-11 13:20 +0200
      Re: [PATCH 13/19] s390: get rid of superfluous __GFP_REPEAT Cornelia Huck <cornelia.huck@de.ibm.com> - 2016-04-11 13:30 +0200
        Re: [PATCH 13/19] s390: get rid of superfluous __GFP_REPEAT Heiko Carstens <heiko.carstens@de.ibm.com> - 2016-04-11 14:50 +0200
    [PATCH 12/19] sparc: get rid of superfluous __GFP_REPEAT Michal Hocko <mhocko@kernel.org> - 2016-04-11 13:20 +0200
    [PATCH 04/19] arm: get rid of superfluous __GFP_REPEAT Michal Hocko <mhocko@kernel.org> - 2016-04-11 13:20 +0200
    [PATCH 03/19] x86/efi: get rid of superfluous __GFP_REPEAT Michal Hocko <mhocko@kernel.org> - 2016-04-11 13:20 +0200
      Re: [PATCH 03/19] x86/efi: get rid of superfluous __GFP_REPEAT Matt Fleming <matt@codeblueprint.co.uk> - 2016-04-12 18:00 +0200
    [PATCH 17/19] dm: get rid of superfluous gfp flags Michal Hocko <mhocko@kernel.org> - 2016-04-11 13:20 +0200
      Re: [PATCH 17/19] dm: get rid of superfluous gfp flags Mikulas Patocka <mpatocka@redhat.com> - 2016-04-15 14:30 +0200
        Re: [PATCH 17/19] dm: get rid of superfluous gfp flags Michal Hocko <mhocko@kernel.org> - 2016-04-15 15:10 +0200
    CC in git cover letter vs patches (was Re: [PATCH 0/19] get rid of  superfluous __GFP_REPORT) Vineet Gupta <Vineet.Gupta1@synopsys.com> - 2016-04-13 13:30 +0200
      Re: CC in git cover letter vs patches (was Re: [PATCH 0/19] get rid  of superfluous __GFP_REPORT) Michal Hocko <mhocko@kernel.org> - 2016-04-13 15:40 +0200

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#1375691 — [PATCH 0/19] get rid of superfluous __GFP_REPORT

From	Michal Hocko <mhocko@kernel.org>
Date	2016-04-11 13:10 +0200
Subject	[PATCH 0/19] get rid of superfluous __GFP_REPORT
Message-ID	<rmHTb-4Qu-3@gated-at.bofh.it>

Hi,
this is the second version of the patchset previously sent [1]

while working on something unrelated I've checked the current usage
of __GFP_REPEAT in the tree. It seems that a majority of the usage is
and always has been bogus because __GFP_REPEAT has always been about
costly high order allocations while we are using it for order-0 or very
small orders very often. It seems that a big pile of them is just a
copy&paste when a code has been adopted from one arch to another.

I think it makes some sense to get rid of them because they are just
making the semantic more unclear. Please note that GFP_REPEAT is
documented as
 * __GFP_REPEAT: Try hard to allocate the memory, but the allocation attempt
 *   _might_ fail.  This depends upon the particular VM implementation.
while !costly requests have basically nofail semantic. So one could
reasonably expect that order-0 request with __GFP_REPEAT will not loop
for ever. This is not implemented right now though.

I would like to move on with __GFP_REPEAT and define a better
semantic for it. One thought was to rename it to __GFP_BEST_EFFORT
which would behave consistently for all orders and guarantee that the
allocation would try as long as it seem feasible or fail eventually.
!costly request would then finally get a request context which neiter
fails too early (GFP_NORETRY) nor endlessly loops in the allocator for
ever (default behavior). Costly high order requests would keep the
current semantic.

$ git grep __GFP_REPEAT next/master | wc -l
111
$ git grep __GFP_REPEAT | wc -l
35

So we are down to the third after this patch series. The remaining places
really seem to be relying on __GFP_REPEAT due to large allocation requests.
This still needs some double checking which I will do later after all the
simple ones are sorted out.

I am touching a lot of arch specific code here and I hope I got it right
but as a matter of fact I even didn't compile test for some archs as I
do not have cross compiler for them. Patches should be quite trivial to
review for stupid compile mistakes though. The tricky parts are usually
hidden by macro definitions and thats where I would appreciate help from
arch maintainers.

I am also interested whether this makes sense in general.

[1] http://lkml.kernel.org/r/1446740160-29094-1-git-send-email-mhocko@kernel.org

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#1375692 — [PATCH 15/19] tile: get rid of superfluous __GFP_REPEAT

From	Michal Hocko <mhocko@kernel.org>
Date	2016-04-11 13:10 +0200
Subject	[PATCH 15/19] tile: get rid of superfluous __GFP_REPEAT
Message-ID	<rmHTc-4Qu-19@gated-at.bofh.it>
In reply to	#1375691

From: Michal Hocko <mhocko@suse.com>

__GFP_REPEAT has a rather weak semantic but since it has been introduced
around 2.6.12 it has been ignored for low order allocations.

pgtable_alloc_one uses __GFP_REPEAT flag for L2_USER_PGTABLE_ORDER but
the order is either 0 or 3 if L2_KERNEL_PGTABLE_SHIFT for HPAGE_SHIFT.
This means that this flag has never been actually useful here because it
has always been used only for PAGE_ALLOC_COSTLY requests.

Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: linux-arch@vger.kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
---
 arch/tile/mm/pgtable.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/tile/mm/pgtable.c b/arch/tile/mm/pgtable.c
index 7bf2491a9c1f..c4d5bf841a7f 100644
--- a/arch/tile/mm/pgtable.c
+++ b/arch/tile/mm/pgtable.c
@@ -231,7 +231,7 @@ void pgd_free(struct mm_struct *mm, pgd_t *pgd)
 struct page *pgtable_alloc_one(struct mm_struct *mm, unsigned long address,
 			       int order)
 {
-	gfp_t flags = GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO;
+	gfp_t flags = GFP_KERNEL|__GFP_ZERO;
 	struct page *p;
 	int i;
 
-- 
2.8.0.rc3

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#1375693 — [PATCH 18/19] crypto: get rid of superfluous __GFP_REPEAT

From	Michal Hocko <mhocko@kernel.org>
Date	2016-04-11 13:10 +0200
Subject	[PATCH 18/19] crypto: get rid of superfluous __GFP_REPEAT
Message-ID	<rmHTc-4Qu-21@gated-at.bofh.it>
In reply to	#1375691

From: Michal Hocko <mhocko@suse.com>

__GFP_REPEAT has a rather weak semantic but since it has been introduced
around 2.6.12 it has been ignored for low order allocations.

lzo_init uses __GFP_REPEAT to allocate LZO1X_MEM_COMPRESS 16K. This is
order 3 allocation request and __GFP_REPEAT is ignored for this size
as well as all <= PAGE_ALLOC_COSTLY requests.

Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Michal Hocko <mhocko@suse.com>
---
 crypto/lzo.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/crypto/lzo.c b/crypto/lzo.c
index 4b3e92525dac..c3f3dd9a28c5 100644
--- a/crypto/lzo.c
+++ b/crypto/lzo.c
@@ -32,7 +32,7 @@ static int lzo_init(struct crypto_tfm *tfm)
 	struct lzo_ctx *ctx = crypto_tfm_ctx(tfm);

 	ctx->lzo_comp_mem = kmalloc(LZO1X_MEM_COMPRESS,
-				    GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
+				    GFP_KERNEL | __GFP_NOWARN);
 	if (!ctx->lzo_comp_mem)
 		ctx->lzo_comp_mem = vmalloc(LZO1X_MEM_COMPRESS);
 	if (!ctx->lzo_comp_mem)
-- 
2.8.0.rc3

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#1378515 — Re: [PATCH 18/19] crypto: get rid of superfluous __GFP_REPEAT

From	Herbert Xu <herbert@gondor.apana.org.au>
Date	2016-04-14 08:30 +0200
Subject	Re: [PATCH 18/19] crypto: get rid of superfluous __GFP_REPEAT
Message-ID	<rnIWS-5Pm-21@gated-at.bofh.it>
In reply to	#1375693

On Mon, Apr 11, 2016 at 01:08:11PM +0200, Michal Hocko wrote:
> From: Michal Hocko <mhocko@suse.com>
> 
> __GFP_REPEAT has a rather weak semantic but since it has been introduced
> around 2.6.12 it has been ignored for low order allocations.
> 
> lzo_init uses __GFP_REPEAT to allocate LZO1X_MEM_COMPRESS 16K. This is
> order 3 allocation request and __GFP_REPEAT is ignored for this size
> as well as all <= PAGE_ALLOC_COSTLY requests.
> 
> Cc: Herbert Xu <herbert@gondor.apana.org.au>
> Cc: "David S. Miller" <davem@davemloft.net>
> Signed-off-by: Michal Hocko <mhocko@suse.com>

Could you please send this patch to the linux-crypto list? Thanks.
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt

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#1378536 — Re: [PATCH 18/19] crypto: get rid of superfluous __GFP_REPEAT

From	Michal Hocko <mhocko@kernel.org>
Date	2016-04-14 09:10 +0200
Subject	Re: [PATCH 18/19] crypto: get rid of superfluous __GFP_REPEAT
Message-ID	<rnJzA-6mi-5@gated-at.bofh.it>
In reply to	#1378515

On Thu 14-04-16 14:27:31, Herbert Xu wrote:
> On Mon, Apr 11, 2016 at 01:08:11PM +0200, Michal Hocko wrote:
> > From: Michal Hocko <mhocko@suse.com>
> > 
> > __GFP_REPEAT has a rather weak semantic but since it has been introduced
> > around 2.6.12 it has been ignored for low order allocations.
> > 
> > lzo_init uses __GFP_REPEAT to allocate LZO1X_MEM_COMPRESS 16K. This is
> > order 3 allocation request and __GFP_REPEAT is ignored for this size
> > as well as all <= PAGE_ALLOC_COSTLY requests.
> > 
> > Cc: Herbert Xu <herbert@gondor.apana.org.au>
> > Cc: "David S. Miller" <davem@davemloft.net>
> > Signed-off-by: Michal Hocko <mhocko@suse.com>
> 
> Could you please send this patch to the linux-crypto list? Thanks.

Will do. Do you prefer it now as a stand along patch or when I repost
the full series. This one doesn't depend on any previous so I can do
both ways.

Thanks!
-- 
Michal Hocko
SUSE Labs

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#1378585 — Re: [PATCH 18/19] crypto: get rid of superfluous __GFP_REPEAT

From	Herbert Xu <herbert@gondor.apana.org.au>
Date	2016-04-14 10:20 +0200
Subject	Re: [PATCH 18/19] crypto: get rid of superfluous __GFP_REPEAT
Message-ID	<rnKFk-79W-25@gated-at.bofh.it>
In reply to	#1378536

On Thu, Apr 14, 2016 at 09:02:17AM +0200, Michal Hocko wrote:
>
> Will do. Do you prefer it now as a stand along patch or when I repost
> the full series. This one doesn't depend on any previous so I can do
> both ways.

I think a standalone patch is fine.

Thanks,
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt

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#1378620 — [PATCH resend] crypto: get rid of superfluous __GFP_REPEAT

From	Michal Hocko <mhocko@kernel.org>
Date	2016-04-14 11:00 +0200
Subject	[PATCH resend] crypto: get rid of superfluous __GFP_REPEAT
Message-ID	<rnLi4-7rI-35@gated-at.bofh.it>
In reply to	#1375693

From: Michal Hocko <mhocko@suse.com>

__GFP_REPEAT has a rather weak semantic but since it has been introduced
around 2.6.12 it has been ignored for low order allocations.

lzo_init uses __GFP_REPEAT to allocate LZO1X_MEM_COMPRESS 16K. This is
order 3 allocation request and __GFP_REPEAT is ignored for this size
as well as all <= PAGE_ALLOC_COSTLY requests.

Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: linux-crypto@vger.kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
---
 crypto/lzo.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/crypto/lzo.c b/crypto/lzo.c
index 4b3e92525dac..c3f3dd9a28c5 100644
--- a/crypto/lzo.c
+++ b/crypto/lzo.c
@@ -32,7 +32,7 @@ static int lzo_init(struct crypto_tfm *tfm)
 	struct lzo_ctx *ctx = crypto_tfm_ctx(tfm);
 
 	ctx->lzo_comp_mem = kmalloc(LZO1X_MEM_COMPRESS,
-				    GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
+				    GFP_KERNEL | __GFP_NOWARN);
 	if (!ctx->lzo_comp_mem)
 		ctx->lzo_comp_mem = vmalloc(LZO1X_MEM_COMPRESS);
 	if (!ctx->lzo_comp_mem)
-- 
2.8.0.rc3

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#1379876 — Re: [PATCH resend] crypto: get rid of superfluous __GFP_REPEAT

From	Herbert Xu <herbert@gondor.apana.org.au>
Date	2016-04-15 16:40 +0200
Subject	Re: [PATCH resend] crypto: get rid of superfluous __GFP_REPEAT
Message-ID	<rod4C-4sD-21@gated-at.bofh.it>
In reply to	#1378620

On Thu, Apr 14, 2016 at 10:51:42AM +0200, Michal Hocko wrote:
> From: Michal Hocko <mhocko@suse.com>
> 
> __GFP_REPEAT has a rather weak semantic but since it has been introduced
> around 2.6.12 it has been ignored for low order allocations.
> 
> lzo_init uses __GFP_REPEAT to allocate LZO1X_MEM_COMPRESS 16K. This is
> order 3 allocation request and __GFP_REPEAT is ignored for this size
> as well as all <= PAGE_ALLOC_COSTLY requests.
> 
> Cc: Herbert Xu <herbert@gondor.apana.org.au>
> Cc: "David S. Miller" <davem@davemloft.net>
> Cc: linux-crypto@vger.kernel.org
> Signed-off-by: Michal Hocko <mhocko@suse.com>

Applied.
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt

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#1375694 — [PATCH 09/19] parisc: get rid of superfluous __GFP_REPEAT

From	Michal Hocko <mhocko@kernel.org>
Date	2016-04-11 13:10 +0200
Subject	[PATCH 09/19] parisc: get rid of superfluous __GFP_REPEAT
Message-ID	<rmHTc-4Qu-15@gated-at.bofh.it>
In reply to	#1375691

From: Michal Hocko <mhocko@suse.com>

__GFP_REPEAT has a rather weak semantic but since it has been introduced
around 2.6.12 it has been ignored for low order allocations.

pmd_alloc_one allocate PMD_ORDER which is 1. This means that this flag
has never been actually useful here because it has always been used only
for PAGE_ALLOC_COSTLY requests.

Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: linux-arch@vger.kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
---
 arch/parisc/include/asm/pgalloc.h | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/arch/parisc/include/asm/pgalloc.h b/arch/parisc/include/asm/pgalloc.h
index 52c3defb40c9..f08dda3f0995 100644
--- a/arch/parisc/include/asm/pgalloc.h
+++ b/arch/parisc/include/asm/pgalloc.h
@@ -63,8 +63,7 @@ static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, pmd_t *pmd)
 
 static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long address)
 {
-	pmd_t *pmd = (pmd_t *)__get_free_pages(GFP_KERNEL|__GFP_REPEAT,
-					       PMD_ORDER);
+	pmd_t *pmd = (pmd_t *)__get_free_pages(GFP_KERNEL, PMD_ORDER);
 	if (pmd)
 		memset(pmd, 0, PAGE_SIZE<<PMD_ORDER);
 	return pmd;
-- 
2.8.0.rc3

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#1375697 — [PATCH 16/19] unicore32: get rid of superfluous __GFP_REPEAT

From	Michal Hocko <mhocko@kernel.org>
Date	2016-04-11 13:10 +0200
Subject	[PATCH 16/19] unicore32: get rid of superfluous __GFP_REPEAT
Message-ID	<rmHTd-4Qu-29@gated-at.bofh.it>
In reply to	#1375691

From: Michal Hocko <mhocko@suse.com>

__GFP_REPEAT has a rather weak semantic but since it has been introduced
around 2.6.12 it has been ignored for low order allocations.

PGALLOC_GFP uses __GFP_REPEAT but it is only used in pte_alloc_one,
pte_alloc_one_kernel which does order-0 request.  This means that this
flag has never been actually useful here because it has always been used
only for PAGE_ALLOC_COSTLY requests.

Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: linux-arch@vger.kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
---
 arch/unicore32/include/asm/pgalloc.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/unicore32/include/asm/pgalloc.h b/arch/unicore32/include/asm/pgalloc.h
index 2e02d1356fdf..26775793c204 100644
--- a/arch/unicore32/include/asm/pgalloc.h
+++ b/arch/unicore32/include/asm/pgalloc.h
@@ -28,7 +28,7 @@ extern void free_pgd_slow(struct mm_struct *mm, pgd_t *pgd);
 #define pgd_alloc(mm)			get_pgd_slow(mm)
 #define pgd_free(mm, pgd)		free_pgd_slow(mm, pgd)
 
-#define PGALLOC_GFP	(GFP_KERNEL | __GFP_NOTRACK | __GFP_REPEAT | __GFP_ZERO)
+#define PGALLOC_GFP	(GFP_KERNEL | __GFP_NOTRACK | __GFP_ZERO)
 
 /*
  * Allocate one PTE table.
-- 
2.8.0.rc3

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#1375702 — [PATCH 08/19] nios2: get rid of superfluous __GFP_REPEAT

From	Michal Hocko <mhocko@kernel.org>
Date	2016-04-11 13:20 +0200
Subject	[PATCH 08/19] nios2: get rid of superfluous __GFP_REPEAT
Message-ID	<rmI2R-4Vk-3@gated-at.bofh.it>
In reply to	#1375691

From: Michal Hocko <mhocko@suse.com>

__GFP_REPEAT has a rather weak semantic but since it has been introduced
around 2.6.12 it has been ignored for low order allocations.

pte_alloc_one{_kernel} allocate PTE_ORDER which is 0. This means that
this flag has never been actually useful here because it has always been
used only for PAGE_ALLOC_COSTLY requests.

Cc: Ley Foon Tan <lftan@altera.com>
Cc: linux-arch@vger.kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
---
 arch/nios2/include/asm/pgalloc.h | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/arch/nios2/include/asm/pgalloc.h b/arch/nios2/include/asm/pgalloc.h
index 6e2985e0a7b9..bb47d08c8ef7 100644
--- a/arch/nios2/include/asm/pgalloc.h
+++ b/arch/nios2/include/asm/pgalloc.h
@@ -42,8 +42,7 @@ static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm,
 {
 	pte_t *pte;
 
-	pte = (pte_t *) __get_free_pages(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO,
-					PTE_ORDER);
+	pte = (pte_t *) __get_free_pages(GFP_KERNEL|__GFP_ZERO, PTE_ORDER);
 
 	return pte;
 }
@@ -53,7 +52,7 @@ static inline pgtable_t pte_alloc_one(struct mm_struct *mm,
 {
 	struct page *pte;
 
-	pte = alloc_pages(GFP_KERNEL | __GFP_REPEAT, PTE_ORDER);
+	pte = alloc_pages(GFP_KERNEL, PTE_ORDER);
 	if (pte) {
 		if (!pgtable_page_ctor(pte)) {
 			__free_page(pte);
-- 
2.8.0.rc3

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#1375703 — [PATCH 01/19] tree wide: get rid of __GFP_REPEAT for order-0 allocations part I

From	Michal Hocko <mhocko@kernel.org>
Date	2016-04-11 13:20 +0200
Subject	[PATCH 01/19] tree wide: get rid of __GFP_REPEAT for order-0 allocations part I
Message-ID	<rmI2R-4Vk-5@gated-at.bofh.it>
In reply to	#1375691

From: Michal Hocko <mhocko@suse.com>

__GFP_REPEAT has a rather weak semantic but since it has been introduced
around 2.6.12 it has been ignored for low order allocations. Yet we have
the full kernel tree with its usage for apparently order-0 allocations.
This is really confusing because __GFP_REPEAT is explicitly documented
to allow allocation failures which is a weaker semantic than the current
order-0 has (basically nofail).

Let's simply drop __GFP_REPEAT from those places. This would allow
to identify place which really need allocator to retry harder and
formulate a more specific semantic for what the flag is supposed to do
actually.

Cc: linux-arch@vger.kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
---
 arch/alpha/include/asm/pgalloc.h         | 4 ++--
 arch/arm/include/asm/pgalloc.h           | 2 +-
 arch/avr32/include/asm/pgalloc.h         | 6 +++---
 arch/cris/include/asm/pgalloc.h          | 4 ++--
 arch/frv/mm/pgalloc.c                    | 6 +++---
 arch/hexagon/include/asm/pgalloc.h       | 4 ++--
 arch/m68k/include/asm/mcf_pgalloc.h      | 4 ++--
 arch/m68k/include/asm/motorola_pgalloc.h | 4 ++--
 arch/m68k/include/asm/sun3_pgalloc.h     | 4 ++--
 arch/metag/include/asm/pgalloc.h         | 5 ++---
 arch/microblaze/include/asm/pgalloc.h    | 4 ++--
 arch/microblaze/mm/pgtable.c             | 3 +--
 arch/mn10300/mm/pgtable.c                | 6 +++---
 arch/openrisc/include/asm/pgalloc.h      | 2 +-
 arch/openrisc/mm/ioremap.c               | 2 +-
 arch/parisc/include/asm/pgalloc.h        | 4 ++--
 arch/powerpc/include/asm/pgalloc-64.h    | 2 +-
 arch/powerpc/mm/pgtable_32.c             | 4 ++--
 arch/powerpc/mm/pgtable_64.c             | 3 +--
 arch/sh/include/asm/pgalloc.h            | 4 ++--
 arch/sparc/mm/init_64.c                  | 6 ++----
 arch/um/kernel/mem.c                     | 4 ++--
 arch/x86/include/asm/pgalloc.h           | 4 ++--
 arch/x86/xen/p2m.c                       | 2 +-
 arch/xtensa/include/asm/pgalloc.h        | 2 +-
 drivers/block/aoe/aoecmd.c               | 2 +-
 26 files changed, 46 insertions(+), 51 deletions(-)

diff --git a/arch/alpha/include/asm/pgalloc.h b/arch/alpha/include/asm/pgalloc.h
index aab14a019c20..c2ebb6f36c9d 100644
--- a/arch/alpha/include/asm/pgalloc.h
+++ b/arch/alpha/include/asm/pgalloc.h
@@ -40,7 +40,7 @@ pgd_free(struct mm_struct *mm, pgd_t *pgd)
 static inline pmd_t *
 pmd_alloc_one(struct mm_struct *mm, unsigned long address)
 {
-	pmd_t *ret = (pmd_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
+	pmd_t *ret = (pmd_t *)__get_free_page(GFP_KERNEL|__GFP_ZERO);
 	return ret;
 }
 
@@ -53,7 +53,7 @@ pmd_free(struct mm_struct *mm, pmd_t *pmd)
 static inline pte_t *
 pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
 {
-	pte_t *pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
+	pte_t *pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_ZERO);
 	return pte;
 }
 
diff --git a/arch/arm/include/asm/pgalloc.h b/arch/arm/include/asm/pgalloc.h
index 19cfab526d13..20febb368844 100644
--- a/arch/arm/include/asm/pgalloc.h
+++ b/arch/arm/include/asm/pgalloc.h
@@ -29,7 +29,7 @@
 
 static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long addr)
 {
-	return (pmd_t *)get_zeroed_page(GFP_KERNEL | __GFP_REPEAT);
+	return (pmd_t *)get_zeroed_page(GFP_KERNEL);
 }
 
 static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
diff --git a/arch/avr32/include/asm/pgalloc.h b/arch/avr32/include/asm/pgalloc.h
index 1aba19d68c5e..db039cb368be 100644
--- a/arch/avr32/include/asm/pgalloc.h
+++ b/arch/avr32/include/asm/pgalloc.h
@@ -43,7 +43,7 @@ static inline void pgd_ctor(void *x)
  */
 static inline pgd_t *pgd_alloc(struct mm_struct *mm)
 {
-	return quicklist_alloc(QUICK_PGD, GFP_KERNEL | __GFP_REPEAT, pgd_ctor);
+	return quicklist_alloc(QUICK_PGD, GFP_KERNEL, pgd_ctor);
 }
 
 static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
@@ -54,7 +54,7 @@ static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
 static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm,
 					  unsigned long address)
 {
-	return quicklist_alloc(QUICK_PT, GFP_KERNEL | __GFP_REPEAT, NULL);
+	return quicklist_alloc(QUICK_PT, GFP_KERNEL, NULL);
 }
 
 static inline pgtable_t pte_alloc_one(struct mm_struct *mm,
@@ -63,7 +63,7 @@ static inline pgtable_t pte_alloc_one(struct mm_struct *mm,
 	struct page *page;
 	void *pg;
 
-	pg = quicklist_alloc(QUICK_PT, GFP_KERNEL | __GFP_REPEAT, NULL);
+	pg = quicklist_alloc(QUICK_PT, GFP_KERNEL, NULL);
 	if (!pg)
 		return NULL;
 
diff --git a/arch/cris/include/asm/pgalloc.h b/arch/cris/include/asm/pgalloc.h
index 235ece437ddd..42f1affb9c2d 100644
--- a/arch/cris/include/asm/pgalloc.h
+++ b/arch/cris/include/asm/pgalloc.h
@@ -24,14 +24,14 @@ static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
 
 static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
 {
-  	pte_t *pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
+	pte_t *pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_ZERO);
  	return pte;
 }
 
 static inline pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long address)
 {
 	struct page *pte;
-	pte = alloc_pages(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO, 0);
+	pte = alloc_pages(GFP_KERNEL|__GFP_ZERO, 0);
 	if (!pte)
 		return NULL;
 	if (!pgtable_page_ctor(pte)) {
diff --git a/arch/frv/mm/pgalloc.c b/arch/frv/mm/pgalloc.c
index 41907d25ed38..c9ed14f6c67d 100644
--- a/arch/frv/mm/pgalloc.c
+++ b/arch/frv/mm/pgalloc.c
@@ -22,7 +22,7 @@ pgd_t swapper_pg_dir[PTRS_PER_PGD] __attribute__((aligned(PAGE_SIZE)));
 
 pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
 {
-	pte_t *pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT);
+	pte_t *pte = (pte_t *)__get_free_page(GFP_KERNEL);
 	if (pte)
 		clear_page(pte);
 	return pte;
@@ -33,9 +33,9 @@ pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long address)
 	struct page *page;
 
 #ifdef CONFIG_HIGHPTE
-	page = alloc_pages(GFP_KERNEL|__GFP_HIGHMEM|__GFP_REPEAT, 0);
+	page = alloc_pages(GFP_KERNEL|__GFP_HIGHMEM, 0);
 #else
-	page = alloc_pages(GFP_KERNEL|__GFP_REPEAT, 0);
+	page = alloc_pages(GFP_KERNEL, 0);
 #endif
 	if (!page)
 		return NULL;
diff --git a/arch/hexagon/include/asm/pgalloc.h b/arch/hexagon/include/asm/pgalloc.h
index 77da3b0ae3c2..eeebf862c46c 100644
--- a/arch/hexagon/include/asm/pgalloc.h
+++ b/arch/hexagon/include/asm/pgalloc.h
@@ -64,7 +64,7 @@ static inline struct page *pte_alloc_one(struct mm_struct *mm,
 {
 	struct page *pte;
 
-	pte = alloc_page(GFP_KERNEL | __GFP_REPEAT | __GFP_ZERO);
+	pte = alloc_page(GFP_KERNEL | __GFP_ZERO);
 	if (!pte)
 		return NULL;
 	if (!pgtable_page_ctor(pte)) {
@@ -78,7 +78,7 @@ static inline struct page *pte_alloc_one(struct mm_struct *mm,
 static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm,
 					  unsigned long address)
 {
-	gfp_t flags =  GFP_KERNEL | __GFP_REPEAT | __GFP_ZERO;
+	gfp_t flags =  GFP_KERNEL | __GFP_ZERO;
 	return (pte_t *) __get_free_page(flags);
 }
 
diff --git a/arch/m68k/include/asm/mcf_pgalloc.h b/arch/m68k/include/asm/mcf_pgalloc.h
index f9924fbcfe42..fb95aed5f428 100644
--- a/arch/m68k/include/asm/mcf_pgalloc.h
+++ b/arch/m68k/include/asm/mcf_pgalloc.h
@@ -14,7 +14,7 @@ extern const char bad_pmd_string[];
 extern inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm,
 	unsigned long address)
 {
-	unsigned long page = __get_free_page(GFP_DMA|__GFP_REPEAT);
+	unsigned long page = __get_free_page(GFP_DMA);
 
 	if (!page)
 		return NULL;
@@ -51,7 +51,7 @@ static inline void __pte_free_tlb(struct mmu_gather *tlb, pgtable_t page,
 static inline struct page *pte_alloc_one(struct mm_struct *mm,
 	unsigned long address)
 {
-	struct page *page = alloc_pages(GFP_DMA|__GFP_REPEAT, 0);
+	struct page *page = alloc_pages(GFP_DMA, 0);
 	pte_t *pte;
 
 	if (!page)
diff --git a/arch/m68k/include/asm/motorola_pgalloc.h b/arch/m68k/include/asm/motorola_pgalloc.h
index 24bcba496c75..c895b987202c 100644
--- a/arch/m68k/include/asm/motorola_pgalloc.h
+++ b/arch/m68k/include/asm/motorola_pgalloc.h
@@ -11,7 +11,7 @@ static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long ad
 {
 	pte_t *pte;
 
-	pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
+	pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_ZERO);
 	if (pte) {
 		__flush_page_to_ram(pte);
 		flush_tlb_kernel_page(pte);
@@ -32,7 +32,7 @@ static inline pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long addres
 	struct page *page;
 	pte_t *pte;
 
-	page = alloc_pages(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO, 0);
+	page = alloc_pages(GFP_KERNEL|__GFP_ZERO, 0);
 	if(!page)
 		return NULL;
 	if (!pgtable_page_ctor(page)) {
diff --git a/arch/m68k/include/asm/sun3_pgalloc.h b/arch/m68k/include/asm/sun3_pgalloc.h
index 0931388de47f..1901f61f926f 100644
--- a/arch/m68k/include/asm/sun3_pgalloc.h
+++ b/arch/m68k/include/asm/sun3_pgalloc.h
@@ -37,7 +37,7 @@ do {							\
 static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm,
 					  unsigned long address)
 {
-	unsigned long page = __get_free_page(GFP_KERNEL|__GFP_REPEAT);
+	unsigned long page = __get_free_page(GFP_KERNEL);
 
 	if (!page)
 		return NULL;
@@ -49,7 +49,7 @@ static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm,
 static inline pgtable_t pte_alloc_one(struct mm_struct *mm,
 					unsigned long address)
 {
-        struct page *page = alloc_pages(GFP_KERNEL|__GFP_REPEAT, 0);
+        struct page *page = alloc_pages(GFP_KERNEL, 0);
 
 	if (page == NULL)
 		return NULL;
diff --git a/arch/metag/include/asm/pgalloc.h b/arch/metag/include/asm/pgalloc.h
index 3104df0a4822..c2caa1ee4360 100644
--- a/arch/metag/include/asm/pgalloc.h
+++ b/arch/metag/include/asm/pgalloc.h
@@ -42,8 +42,7 @@ static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
 static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm,
 					  unsigned long address)
 {
-	pte_t *pte = (pte_t *)__get_free_page(GFP_KERNEL | __GFP_REPEAT |
-					      __GFP_ZERO);
+	pte_t *pte = (pte_t *)__get_free_page(GFP_KERNEL | __GFP_ZERO);
 	return pte;
 }
 
@@ -51,7 +50,7 @@ static inline pgtable_t pte_alloc_one(struct mm_struct *mm,
 				      unsigned long address)
 {
 	struct page *pte;
-	pte = alloc_pages(GFP_KERNEL | __GFP_REPEAT | __GFP_ZERO, 0);
+	pte = alloc_pages(GFP_KERNEL  | __GFP_ZERO, 0);
 	if (!pte)
 		return NULL;
 	if (!pgtable_page_ctor(pte)) {
diff --git a/arch/microblaze/include/asm/pgalloc.h b/arch/microblaze/include/asm/pgalloc.h
index 61436d69775c..7c89390c0c13 100644
--- a/arch/microblaze/include/asm/pgalloc.h
+++ b/arch/microblaze/include/asm/pgalloc.h
@@ -116,9 +116,9 @@ static inline struct page *pte_alloc_one(struct mm_struct *mm,
 	struct page *ptepage;
 
 #ifdef CONFIG_HIGHPTE
-	int flags = GFP_KERNEL | __GFP_HIGHMEM | __GFP_REPEAT;
+	int flags = GFP_KERNEL | __GFP_HIGHMEM;
 #else
-	int flags = GFP_KERNEL | __GFP_REPEAT;
+	int flags = GFP_KERNEL;
 #endif
 
 	ptepage = alloc_pages(flags, 0);
diff --git a/arch/microblaze/mm/pgtable.c b/arch/microblaze/mm/pgtable.c
index 4f4520e779a5..eb99fcc76088 100644
--- a/arch/microblaze/mm/pgtable.c
+++ b/arch/microblaze/mm/pgtable.c
@@ -239,8 +239,7 @@ __init_refok pte_t *pte_alloc_one_kernel(struct mm_struct *mm,
 {
 	pte_t *pte;
 	if (mem_init_done) {
-		pte = (pte_t *)__get_free_page(GFP_KERNEL |
-					__GFP_REPEAT | __GFP_ZERO);
+		pte = (pte_t *)__get_free_page(GFP_KERNEL | __GFP_ZERO);
 	} else {
 		pte = (pte_t *)early_get_page();
 		if (pte)
diff --git a/arch/mn10300/mm/pgtable.c b/arch/mn10300/mm/pgtable.c
index e77a7c728081..9577cf768875 100644
--- a/arch/mn10300/mm/pgtable.c
+++ b/arch/mn10300/mm/pgtable.c
@@ -63,7 +63,7 @@ void set_pmd_pfn(unsigned long vaddr, unsigned long pfn, pgprot_t flags)
 
 pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
 {
-	pte_t *pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT);
+	pte_t *pte = (pte_t *)__get_free_page(GFP_KERNEL);
 	if (pte)
 		clear_page(pte);
 	return pte;
@@ -74,9 +74,9 @@ struct page *pte_alloc_one(struct mm_struct *mm, unsigned long address)
 	struct page *pte;
 
 #ifdef CONFIG_HIGHPTE
-	pte = alloc_pages(GFP_KERNEL|__GFP_HIGHMEM|__GFP_REPEAT, 0);
+	pte = alloc_pages(GFP_KERNEL|__GFP_HIGHMEM, 0);
 #else
-	pte = alloc_pages(GFP_KERNEL|__GFP_REPEAT, 0);
+	pte = alloc_pages(GFP_KERNEL, 0);
 #endif
 	if (!pte)
 		return NULL;
diff --git a/arch/openrisc/include/asm/pgalloc.h b/arch/openrisc/include/asm/pgalloc.h
index 21484e5b9e9a..87eebd185089 100644
--- a/arch/openrisc/include/asm/pgalloc.h
+++ b/arch/openrisc/include/asm/pgalloc.h
@@ -77,7 +77,7 @@ static inline struct page *pte_alloc_one(struct mm_struct *mm,
 					 unsigned long address)
 {
 	struct page *pte;
-	pte = alloc_pages(GFP_KERNEL|__GFP_REPEAT, 0);
+	pte = alloc_pages(GFP_KERNEL, 0);
 	if (!pte)
 		return NULL;
 	clear_page(page_address(pte));
diff --git a/arch/openrisc/mm/ioremap.c b/arch/openrisc/mm/ioremap.c
index 62b08ef392be..5b2a95116e8f 100644
--- a/arch/openrisc/mm/ioremap.c
+++ b/arch/openrisc/mm/ioremap.c
@@ -122,7 +122,7 @@ pte_t __init_refok *pte_alloc_one_kernel(struct mm_struct *mm,
 	pte_t *pte;
 
 	if (likely(mem_init_done)) {
-		pte = (pte_t *) __get_free_page(GFP_KERNEL | __GFP_REPEAT);
+		pte = (pte_t *) __get_free_page(GFP_KERNEL);
 	} else {
 		pte = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE);
 #if 0
diff --git a/arch/parisc/include/asm/pgalloc.h b/arch/parisc/include/asm/pgalloc.h
index f2fd327dce2e..52c3defb40c9 100644
--- a/arch/parisc/include/asm/pgalloc.h
+++ b/arch/parisc/include/asm/pgalloc.h
@@ -124,7 +124,7 @@ pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmd, pte_t *pte)
 static inline pgtable_t
 pte_alloc_one(struct mm_struct *mm, unsigned long address)
 {
-	struct page *page = alloc_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
+	struct page *page = alloc_page(GFP_KERNEL|__GFP_ZERO);
 	if (!page)
 		return NULL;
 	if (!pgtable_page_ctor(page)) {
@@ -137,7 +137,7 @@ pte_alloc_one(struct mm_struct *mm, unsigned long address)
 static inline pte_t *
 pte_alloc_one_kernel(struct mm_struct *mm, unsigned long addr)
 {
-	pte_t *pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
+	pte_t *pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_ZERO);
 	return pte;
 }
 
diff --git a/arch/powerpc/include/asm/pgalloc-64.h b/arch/powerpc/include/asm/pgalloc-64.h
index 8d5fc3ac43da..5dcfde5dc673 100644
--- a/arch/powerpc/include/asm/pgalloc-64.h
+++ b/arch/powerpc/include/asm/pgalloc-64.h
@@ -88,7 +88,7 @@ static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmd,
 static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm,
 					  unsigned long address)
 {
-	return (pte_t *)__get_free_page(GFP_KERNEL | __GFP_REPEAT | __GFP_ZERO);
+	return (pte_t *)__get_free_page(GFP_KERNEL | __GFP_ZERO);
 }
 
 static inline pgtable_t pte_alloc_one(struct mm_struct *mm,
diff --git a/arch/powerpc/mm/pgtable_32.c b/arch/powerpc/mm/pgtable_32.c
index bf7bf32b54f8..7f922f557936 100644
--- a/arch/powerpc/mm/pgtable_32.c
+++ b/arch/powerpc/mm/pgtable_32.c
@@ -84,7 +84,7 @@ __init_refok pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long add
 	pte_t *pte;
 
 	if (slab_is_available()) {
-		pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
+		pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_ZERO);
 	} else {
 		pte = __va(memblock_alloc(PAGE_SIZE, PAGE_SIZE));
 		if (pte)
@@ -97,7 +97,7 @@ pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long address)
 {
 	struct page *ptepage;
 
-	gfp_t flags = GFP_KERNEL | __GFP_REPEAT | __GFP_ZERO;
+	gfp_t flags = GFP_KERNEL | __GFP_ZERO;
 
 	ptepage = alloc_pages(flags, 0);
 	if (!ptepage)
diff --git a/arch/powerpc/mm/pgtable_64.c b/arch/powerpc/mm/pgtable_64.c
index 347106080bb1..03cc73e86675 100644
--- a/arch/powerpc/mm/pgtable_64.c
+++ b/arch/powerpc/mm/pgtable_64.c
@@ -386,8 +386,7 @@ static pte_t *get_from_cache(struct mm_struct *mm)
 static pte_t *__alloc_for_cache(struct mm_struct *mm, int kernel)
 {
 	void *ret = NULL;
-	struct page *page = alloc_page(GFP_KERNEL | __GFP_NOTRACK |
-				       __GFP_REPEAT | __GFP_ZERO);
+	struct page *page = alloc_page(GFP_KERNEL | __GFP_NOTRACK | __GFP_ZERO);
 	if (!page)
 		return NULL;
 	if (!kernel && !pgtable_page_ctor(page)) {
diff --git a/arch/sh/include/asm/pgalloc.h b/arch/sh/include/asm/pgalloc.h
index a33673b3687d..f3f42c84c40f 100644
--- a/arch/sh/include/asm/pgalloc.h
+++ b/arch/sh/include/asm/pgalloc.h
@@ -34,7 +34,7 @@ static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmd,
 static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm,
 					  unsigned long address)
 {
-	return quicklist_alloc(QUICK_PT, GFP_KERNEL | __GFP_REPEAT, NULL);
+	return quicklist_alloc(QUICK_PT, GFP_KERNEL, NULL);
 }
 
 static inline pgtable_t pte_alloc_one(struct mm_struct *mm,
@@ -43,7 +43,7 @@ static inline pgtable_t pte_alloc_one(struct mm_struct *mm,
 	struct page *page;
 	void *pg;
 
-	pg = quicklist_alloc(QUICK_PT, GFP_KERNEL | __GFP_REPEAT, NULL);
+	pg = quicklist_alloc(QUICK_PT, GFP_KERNEL, NULL);
 	if (!pg)
 		return NULL;
 	page = virt_to_page(pg);
diff --git a/arch/sparc/mm/init_64.c b/arch/sparc/mm/init_64.c
index 1cfe6aab7a11..43bbeeb84268 100644
--- a/arch/sparc/mm/init_64.c
+++ b/arch/sparc/mm/init_64.c
@@ -2713,8 +2713,7 @@ void __flush_tlb_all(void)
 pte_t *pte_alloc_one_kernel(struct mm_struct *mm,
 			    unsigned long address)
 {
-	struct page *page = alloc_page(GFP_KERNEL | __GFP_NOTRACK |
-				       __GFP_REPEAT | __GFP_ZERO);
+	struct page *page = alloc_page(GFP_KERNEL | __GFP_NOTRACK | __GFP_ZERO);
 	pte_t *pte = NULL;
 
 	if (page)
@@ -2726,8 +2725,7 @@ pte_t *pte_alloc_one_kernel(struct mm_struct *mm,
 pgtable_t pte_alloc_one(struct mm_struct *mm,
 			unsigned long address)
 {
-	struct page *page = alloc_page(GFP_KERNEL | __GFP_NOTRACK |
-				       __GFP_REPEAT | __GFP_ZERO);
+	struct page *page = alloc_page(GFP_KERNEL | __GFP_NOTRACK | __GFP_ZERO);
 	if (!page)
 		return NULL;
 	if (!pgtable_page_ctor(page)) {
diff --git a/arch/um/kernel/mem.c b/arch/um/kernel/mem.c
index b2a2dff50b4e..e7437ec62710 100644
--- a/arch/um/kernel/mem.c
+++ b/arch/um/kernel/mem.c
@@ -204,7 +204,7 @@ pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
 {
 	pte_t *pte;
 
-	pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
+	pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_ZERO);
 	return pte;
 }
 
@@ -212,7 +212,7 @@ pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long address)
 {
 	struct page *pte;
 
-	pte = alloc_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
+	pte = alloc_page(GFP_KERNEL|__GFP_ZERO);
 	if (!pte)
 		return NULL;
 	if (!pgtable_page_ctor(pte)) {
diff --git a/arch/x86/include/asm/pgalloc.h b/arch/x86/include/asm/pgalloc.h
index bf7f8b55b0f9..574c23cf761a 100644
--- a/arch/x86/include/asm/pgalloc.h
+++ b/arch/x86/include/asm/pgalloc.h
@@ -81,7 +81,7 @@ static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmd,
 static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long addr)
 {
 	struct page *page;
-	page = alloc_pages(GFP_KERNEL | __GFP_REPEAT | __GFP_ZERO, 0);
+	page = alloc_pages(GFP_KERNEL |  __GFP_ZERO, 0);
 	if (!page)
 		return NULL;
 	if (!pgtable_pmd_page_ctor(page)) {
@@ -125,7 +125,7 @@ static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, pud_t *pud)
 
 static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long addr)
 {
-	return (pud_t *)get_zeroed_page(GFP_KERNEL|__GFP_REPEAT);
+	return (pud_t *)get_zeroed_page(GFP_KERNEL);
 }
 
 static inline void pud_free(struct mm_struct *mm, pud_t *pud)
diff --git a/arch/x86/xen/p2m.c b/arch/x86/xen/p2m.c
index cab9f766bb06..dd2a49a8aacc 100644
--- a/arch/x86/xen/p2m.c
+++ b/arch/x86/xen/p2m.c
@@ -182,7 +182,7 @@ static void * __ref alloc_p2m_page(void)
 	if (unlikely(!slab_is_available()))
 		return alloc_bootmem_align(PAGE_SIZE, PAGE_SIZE);
 
-	return (void *)__get_free_page(GFP_KERNEL | __GFP_REPEAT);
+	return (void *)__get_free_page(GFP_KERNEL);
 }
 
 static void __ref free_p2m_page(void *p)
diff --git a/arch/xtensa/include/asm/pgalloc.h b/arch/xtensa/include/asm/pgalloc.h
index d38eb9237e64..1065bc8bcae5 100644
--- a/arch/xtensa/include/asm/pgalloc.h
+++ b/arch/xtensa/include/asm/pgalloc.h
@@ -44,7 +44,7 @@ static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm,
 	pte_t *ptep;
 	int i;
 
-	ptep = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT);
+	ptep = (pte_t *)__get_free_page(GFP_KERNEL);
 	if (!ptep)
 		return NULL;
 	for (i = 0; i < 1024; i++)
diff --git a/drivers/block/aoe/aoecmd.c b/drivers/block/aoe/aoecmd.c
index d597e432e195..ab19adb07a12 100644
--- a/drivers/block/aoe/aoecmd.c
+++ b/drivers/block/aoe/aoecmd.c
@@ -1750,7 +1750,7 @@ aoecmd_init(void)
 	int ret;
 
 	/* get_zeroed_page returns page with ref count 1 */
-	p = (void *) get_zeroed_page(GFP_KERNEL | __GFP_REPEAT);
+	p = (void *) get_zeroed_page(GFP_KERNEL);
 	if (!p)
 		return -ENOMEM;
 	empty_page = virt_to_page(p);
-- 
2.8.0.rc3

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#1379275 — Re: [PATCH 01/19] tree wide: get rid of __GFP_REPEAT for order-0 allocations part I

From	David Rientjes <rientjes@google.com>
Date	2016-04-14 22:00 +0200
Subject	Re: [PATCH 01/19] tree wide: get rid of __GFP_REPEAT for order-0 allocations part I
Message-ID	<rnVAJ-7pv-5@gated-at.bofh.it>
In reply to	#1375703

On Mon, 11 Apr 2016, Michal Hocko wrote:

> From: Michal Hocko <mhocko@suse.com>
> 
> __GFP_REPEAT has a rather weak semantic but since it has been introduced
> around 2.6.12 it has been ignored for low order allocations. Yet we have
> the full kernel tree with its usage for apparently order-0 allocations.
> This is really confusing because __GFP_REPEAT is explicitly documented
> to allow allocation failures which is a weaker semantic than the current
> order-0 has (basically nofail).
> 
> Let's simply drop __GFP_REPEAT from those places. This would allow
> to identify place which really need allocator to retry harder and
> formulate a more specific semantic for what the flag is supposed to do
> actually.
> 
> Cc: linux-arch@vger.kernel.org
> Signed-off-by: Michal Hocko <mhocko@suse.com>

I did exactly this before, and Andrew objected saying that __GFP_REPEAT 
may not be needed for the current page allocator's implementation but 
could with others and that setting __GFP_REPEAT for an allocation 
provided useful information with regards to intent.  At the time, I 
attempted to eliminate __GFP_REPEAT entirely.

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#1379519 — Re: [PATCH 01/19] tree wide: get rid of __GFP_REPEAT for order-0 allocations part I

From	Michal Hocko <mhocko@kernel.org>
Date	2016-04-15 09:50 +0200
Subject	Re: [PATCH 01/19] tree wide: get rid of __GFP_REPEAT for order-0 allocations part I
Message-ID	<ro6FQ-7VI-11@gated-at.bofh.it>
In reply to	#1379275

On Thu 14-04-16 12:56:28, David Rientjes wrote:
> On Mon, 11 Apr 2016, Michal Hocko wrote:
> 
> > From: Michal Hocko <mhocko@suse.com>
> > 
> > __GFP_REPEAT has a rather weak semantic but since it has been introduced
> > around 2.6.12 it has been ignored for low order allocations. Yet we have
> > the full kernel tree with its usage for apparently order-0 allocations.
> > This is really confusing because __GFP_REPEAT is explicitly documented
> > to allow allocation failures which is a weaker semantic than the current
> > order-0 has (basically nofail).
> > 
> > Let's simply drop __GFP_REPEAT from those places. This would allow
> > to identify place which really need allocator to retry harder and
> > formulate a more specific semantic for what the flag is supposed to do
> > actually.
> > 
> > Cc: linux-arch@vger.kernel.org
> > Signed-off-by: Michal Hocko <mhocko@suse.com>
> 
> I did exactly this before, and Andrew objected saying that __GFP_REPEAT 
> may not be needed for the current page allocator's implementation but 
> could with others and that setting __GFP_REPEAT for an allocation 
> provided useful information with regards to intent.

From what I've seen it was more a copy&paste of the arch code which
spread out this flag and there was also a misleading usage.

> At the time, I attempted to eliminate __GFP_REPEAT entirely.

This is not my plan. I actually want to provide a useful semantic for
something like this flag - aka try really hard but eventually fail
for all orders and stop being special only for those that are costly. I
will call it __GFP_BEST_EFFORT. But I have to clean up the current usage
first. Costly orders will keep __GFP_REPEAT because the intent is clear
there. All others will lose the flag and then we can start adding
__GFP_BEST_EFFORT where it matters also for lower orders.
-- 
Michal Hocko
SUSE Labs

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#1375704 — [PATCH 06/19] arc: get rid of superfluous __GFP_REPEAT

From	Michal Hocko <mhocko@kernel.org>
Date	2016-04-11 13:20 +0200
Subject	[PATCH 06/19] arc: get rid of superfluous __GFP_REPEAT
Message-ID	<rmI2R-4Vk-9@gated-at.bofh.it>
In reply to	#1375691

From: Michal Hocko <mhocko@suse.com>

__GFP_REPEAT has a rather weak semantic but since it has been introduced
around 2.6.12 it has been ignored for low order allocations.

pte_alloc_one_kernel uses __get_order_pte but this is obviously
always zero because BITS_FOR_PTE is not larger than 9 yet the page
size is always larger than 4K.  This means that this flag has never
been actually useful here because it has always been used only for
PAGE_ALLOC_COSTLY requests.

Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: linux-arch@vger.kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
---
 arch/arc/include/asm/pgalloc.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arc/include/asm/pgalloc.h b/arch/arc/include/asm/pgalloc.h
index 86ed671286df..3749234b7419 100644
--- a/arch/arc/include/asm/pgalloc.h
+++ b/arch/arc/include/asm/pgalloc.h
@@ -95,7 +95,7 @@ static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm,
 {
 	pte_t *pte;
 
-	pte = (pte_t *) __get_free_pages(GFP_KERNEL | __GFP_REPEAT | __GFP_ZERO,
+	pte = (pte_t *) __get_free_pages(GFP_KERNEL | __GFP_ZERO,
 					 __get_order_pte());
 
 	return pte;
@@ -107,7 +107,7 @@ pte_alloc_one(struct mm_struct *mm, unsigned long address)
 	pgtable_t pte_pg;
 	struct page *page;
 
-	pte_pg = (pgtable_t)__get_free_pages(GFP_KERNEL | __GFP_REPEAT, __get_order_pte());
+	pte_pg = (pgtable_t)__get_free_pages(GFP_KERNEL, __get_order_pte());
 	if (!pte_pg)
 		return 0;
 	memzero((void *)pte_pg, PTRS_PER_PTE * sizeof(pte_t));
-- 
2.8.0.rc3

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#1376018 — Re: [PATCH 06/19] arc: get rid of superfluous __GFP_REPEAT

From	Vineet Gupta <Vineet.Gupta1@synopsys.com>
Date	2016-04-11 16:30 +0200
Subject	Re: [PATCH 06/19] arc: get rid of superfluous __GFP_REPEAT
Message-ID	<rmL0K-7lT-13@gated-at.bofh.it>
In reply to	#1375704

On Monday 11 April 2016 04:38 PM, Michal Hocko wrote:
> From: Michal Hocko <mhocko@suse.com>
>
> __GFP_REPEAT has a rather weak semantic but since it has been introduced
> around 2.6.12 it has been ignored for low order allocations.
>
> pte_alloc_one_kernel uses __get_order_pte but this is obviously
> always zero because BITS_FOR_PTE is not larger than 9 yet the page
> size is always larger than 4K.  This means that this flag has never
> been actually useful here because it has always been used only for
> PAGE_ALLOC_COSTLY requests.
>
> Cc: Vineet Gupta <vgupta@synopsys.com>
> Cc: linux-arch@vger.kernel.org
> Signed-off-by: Michal Hocko <mhocko@suse.com>

Acked-by: Vineet Gupta <vgupta@synopsys.com>

Thx,
-Vineet

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#1375705 — [PATCH 11/19] powerpc: get rid of superfluous __GFP_REPEAT

From	Michal Hocko <mhocko@kernel.org>
Date	2016-04-11 13:20 +0200
Subject	[PATCH 11/19] powerpc: get rid of superfluous __GFP_REPEAT
Message-ID	<rmI2S-4Vk-11@gated-at.bofh.it>
In reply to	#1375691

From: Michal Hocko <mhocko@suse.com>

__GFP_REPEAT has a rather weak semantic but since it has been introduced
around 2.6.12 it has been ignored for low order allocations.

{pud,pmd}_alloc_one are allocating from {PGT,PUD}_CACHE initialized in
pgtable_cache_init which doesn't have larger than sizeof(void *) << 12
size and that fits into !costly allocation request size. This means that
this flag has never been actually useful here because it has always been
used only for PAGE_ALLOC_COSTLY requests.

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: linux-arch@vger.kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
---
 arch/powerpc/include/asm/pgalloc-64.h | 6 +++---
 arch/powerpc/mm/hugetlbpage.c         | 2 +-
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/powerpc/include/asm/pgalloc-64.h b/arch/powerpc/include/asm/pgalloc-64.h
index 5dcfde5dc673..aaa6d3bc5d86 100644
--- a/arch/powerpc/include/asm/pgalloc-64.h
+++ b/arch/powerpc/include/asm/pgalloc-64.h
@@ -58,7 +58,7 @@ static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
 static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long addr)
 {
 	return kmem_cache_alloc(PGT_CACHE(PUD_INDEX_SIZE),
-				GFP_KERNEL|__GFP_REPEAT);
+				GFP_KERNEL);
 }
 
 static inline void pud_free(struct mm_struct *mm, pud_t *pud)
@@ -181,7 +181,7 @@ static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, pud_t *pud)
 static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long addr)
 {
 	return kmem_cache_alloc(PGT_CACHE(PUD_INDEX_SIZE),
-				GFP_KERNEL|__GFP_REPEAT);
+				GFP_KERNEL);
 }
 
 static inline void pud_free(struct mm_struct *mm, pud_t *pud)
@@ -245,7 +245,7 @@ static inline void __pte_free_tlb(struct mmu_gather *tlb, pgtable_t table,
 static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long addr)
 {
 	return kmem_cache_alloc(PGT_CACHE(PMD_CACHE_INDEX),
-				GFP_KERNEL|__GFP_REPEAT);
+				GFP_KERNEL);
 }
 
 static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c
index a4a90a869999..6cfc48c94d4b 100644
--- a/arch/powerpc/mm/hugetlbpage.c
+++ b/arch/powerpc/mm/hugetlbpage.c
@@ -73,7 +73,7 @@ static int __hugepte_alloc(struct mm_struct *mm, hugepd_t *hpdp,
 	cachep = PGT_CACHE(pdshift - pshift);
 #endif
 
-	new = kmem_cache_zalloc(cachep, GFP_KERNEL|__GFP_REPEAT);
+	new = kmem_cache_zalloc(cachep, GFP_KERNEL);
 
 	BUG_ON(pshift > HUGEPD_SHIFT_MASK);
 	BUG_ON((unsigned long)new & HUGEPD_SHIFT_MASK);
-- 
2.8.0.rc3

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#1375706 — [PATCH 10/19] score: get rid of superfluous __GFP_REPEAT

From	Michal Hocko <mhocko@kernel.org>
Date	2016-04-11 13:20 +0200
Subject	[PATCH 10/19] score: get rid of superfluous __GFP_REPEAT
Message-ID	<rmI2R-4Vk-7@gated-at.bofh.it>
In reply to	#1375691

From: Michal Hocko <mhocko@suse.com>

__GFP_REPEAT has a rather weak semantic but since it has been introduced
around 2.6.12 it has been ignored for low order allocations.

pte_alloc_one{_kernel} allocate PTE_ORDER which is 0. This means that
this flag has never been actually useful here because it has always been
used only for PAGE_ALLOC_COSTLY requests.

Cc: Chen Liqin <liqin.linux@gmail.com>
Cc: Lennox Wu <lennox.wu@gmail.com>
Cc: linux-arch@vger.kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
---
 arch/score/include/asm/pgalloc.h | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/arch/score/include/asm/pgalloc.h b/arch/score/include/asm/pgalloc.h
index 2e067657db98..49b012d78c1a 100644
--- a/arch/score/include/asm/pgalloc.h
+++ b/arch/score/include/asm/pgalloc.h
@@ -42,8 +42,7 @@ static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm,
 {
 	pte_t *pte;
 
-	pte = (pte_t *) __get_free_pages(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO,
-					PTE_ORDER);
+	pte = (pte_t *) __get_free_pages(GFP_KERNEL|__GFP_ZERO, PTE_ORDER);
 
 	return pte;
 }
@@ -53,7 +52,7 @@ static inline struct page *pte_alloc_one(struct mm_struct *mm,
 {
 	struct page *pte;
 
-	pte = alloc_pages(GFP_KERNEL | __GFP_REPEAT, PTE_ORDER);
+	pte = alloc_pages(GFP_KERNEL, PTE_ORDER);
 	if (!pte)
 		return NULL;
 	clear_highpage(pte);
-- 
2.8.0.rc3

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#1375707 — [PATCH 07/19] mips: get rid of superfluous __GFP_REPEAT

From	Michal Hocko <mhocko@kernel.org>
Date	2016-04-11 13:20 +0200
Subject	[PATCH 07/19] mips: get rid of superfluous __GFP_REPEAT
Message-ID	<rmI2S-4Vk-13@gated-at.bofh.it>
In reply to	#1375691

From: Michal Hocko <mhocko@suse.com>

__GFP_REPEAT has a rather weak semantic but since it has been introduced
around 2.6.12 it has been ignored for low order allocations.

pte_alloc_one{_kernel}, pmd_alloc_one allocate PTE_ORDER resp. PMD_ORDER
but both are not larger than 1. This means that this flag has never
been actually useful here because it has always been used only for
PAGE_ALLOC_COSTLY requests.

Cc: John Crispin <blogic@openwrt.org>
Cc: linux-arch@vger.kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
---
 arch/mips/include/asm/pgalloc.h | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/arch/mips/include/asm/pgalloc.h b/arch/mips/include/asm/pgalloc.h
index b336037e8768..93c079a1cfc8 100644
--- a/arch/mips/include/asm/pgalloc.h
+++ b/arch/mips/include/asm/pgalloc.h
@@ -69,7 +69,7 @@ static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm,
 {
 	pte_t *pte;
 
-	pte = (pte_t *) __get_free_pages(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO, PTE_ORDER);
+	pte = (pte_t *) __get_free_pages(GFP_KERNEL|__GFP_ZERO, PTE_ORDER);
 
 	return pte;
 }
@@ -79,7 +79,7 @@ static inline struct page *pte_alloc_one(struct mm_struct *mm,
 {
 	struct page *pte;
 
-	pte = alloc_pages(GFP_KERNEL | __GFP_REPEAT, PTE_ORDER);
+	pte = alloc_pages(GFP_KERNEL, PTE_ORDER);
 	if (!pte)
 		return NULL;
 	clear_highpage(pte);
@@ -113,7 +113,7 @@ static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long address)
 {
 	pmd_t *pmd;
 
-	pmd = (pmd_t *) __get_free_pages(GFP_KERNEL|__GFP_REPEAT, PMD_ORDER);
+	pmd = (pmd_t *) __get_free_pages(GFP_KERNEL, PMD_ORDER);
 	if (pmd)
 		pmd_init((unsigned long)pmd, (unsigned long)invalid_pte_table);
 	return pmd;
-- 
2.8.0.rc3

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#1375709 — [PATCH 19/19] jbd2: get rid of superfluous __GFP_REPEAT

From	Michal Hocko <mhocko@kernel.org>
Date	2016-04-11 13:20 +0200
Subject	[PATCH 19/19] jbd2: get rid of superfluous __GFP_REPEAT
Message-ID	<rmI2S-4Vk-15@gated-at.bofh.it>
In reply to	#1375691

From: Michal Hocko <mhocko@suse.com>

jbd2_alloc is explicit about its allocation preferences wrt. the
allocation size. Sub page allocations go to the slab allocator
and larger are using either the page allocator or vmalloc. This
is all good but the logic is unnecessarily complex.
1) as per Ted, the vmalloc fallback is a left-over:
: jbd2_alloc is only passed in the bh->b_size, which can't be >
: PAGE_SIZE, so the code path that calls vmalloc() should never get
: called.  When we conveted jbd2_alloc() to suppor sub-page size
: allocations in commit d2eecb039368, there was an assumption that it
: could be called with a size greater than PAGE_SIZE, but that's
: certaily not true today.
Moreover vmalloc allocation might even lead to a deadlock because
the callers expect GFP_NOFS context while vmalloc is GFP_KERNEL.

2) __GFP_REPEAT for requests <= PAGE_ALLOC_COSTLY_ORDER is ignored
since the flag was introduced.

Let's simplify the code flow and use the slab allocator for sub-page
requests and the page allocator for others. Even though order > 0 is
not currently used as per above leave that option open.

Cc: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Michal Hocko <mhocko@suse.com>
---
 fs/jbd2/journal.c | 32 +++++++-------------------------
 1 file changed, 7 insertions(+), 25 deletions(-)

diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c
index 435f0b26ac20..bd7c31d8c05e 100644
--- a/fs/jbd2/journal.c
+++ b/fs/jbd2/journal.c
@@ -2328,18 +2328,10 @@ void *jbd2_alloc(size_t size, gfp_t flags)
 
 	BUG_ON(size & (size-1)); /* Must be a power of 2 */
 
-	flags |= __GFP_REPEAT;
-	if (size == PAGE_SIZE)
-		ptr = (void *)__get_free_pages(flags, 0);
-	else if (size > PAGE_SIZE) {
-		int order = get_order(size);
-
-		if (order < 3)
-			ptr = (void *)__get_free_pages(flags, order);
-		else
-			ptr = vmalloc(size);
-	} else
+	if (size < PAGE_SIZE)
 		ptr = kmem_cache_alloc(get_slab(size), flags);
+	else
+		ptr = (void *)__get_free_pages(flags, get_order(size));
 
 	/* Check alignment; SLUB has gotten this wrong in the past,
 	 * and this can lead to user data corruption! */
@@ -2350,20 +2342,10 @@ void *jbd2_alloc(size_t size, gfp_t flags)
 
 void jbd2_free(void *ptr, size_t size)
 {
-	if (size == PAGE_SIZE) {
-		free_pages((unsigned long)ptr, 0);
-		return;
-	}
-	if (size > PAGE_SIZE) {
-		int order = get_order(size);
-
-		if (order < 3)
-			free_pages((unsigned long)ptr, order);
-		else
-			vfree(ptr);
-		return;
-	}
-	kmem_cache_free(get_slab(size), ptr);
+	if (size < PAGE_SIZE)
+		kmem_cache_free(get_slab(size), ptr);
+	else
+		free_pages((unsigned long)ptr, get_order(size));
 };
 
 /*
-- 
2.8.0.rc3

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Page 1 of 2 [1] 2 Next page →

csiph-web

[PATCH 0/19] get rid of superfluous __GFP_REPORT

Contents

#1375691 — [PATCH 0/19] get rid of superfluous __GFP_REPORT

#1375692 — [PATCH 15/19] tile: get rid of superfluous __GFP_REPEAT

#1375693 — [PATCH 18/19] crypto: get rid of superfluous __GFP_REPEAT

#1378515 — Re: [PATCH 18/19] crypto: get rid of superfluous __GFP_REPEAT

#1378536 — Re: [PATCH 18/19] crypto: get rid of superfluous __GFP_REPEAT

#1378585 — Re: [PATCH 18/19] crypto: get rid of superfluous __GFP_REPEAT

#1378620 — [PATCH resend] crypto: get rid of superfluous __GFP_REPEAT

#1379876 — Re: [PATCH resend] crypto: get rid of superfluous __GFP_REPEAT

#1375694 — [PATCH 09/19] parisc: get rid of superfluous __GFP_REPEAT

#1375697 — [PATCH 16/19] unicore32: get rid of superfluous __GFP_REPEAT

#1375702 — [PATCH 08/19] nios2: get rid of superfluous __GFP_REPEAT

#1375703 — [PATCH 01/19] tree wide: get rid of __GFP_REPEAT for order-0 allocations part I

#1379275 — Re: [PATCH 01/19] tree wide: get rid of __GFP_REPEAT for order-0 allocations part I

#1379519 — Re: [PATCH 01/19] tree wide: get rid of __GFP_REPEAT for order-0 allocations part I

#1375704 — [PATCH 06/19] arc: get rid of superfluous __GFP_REPEAT

#1376018 — Re: [PATCH 06/19] arc: get rid of superfluous __GFP_REPEAT

#1375705 — [PATCH 11/19] powerpc: get rid of superfluous __GFP_REPEAT

#1375706 — [PATCH 10/19] score: get rid of superfluous __GFP_REPEAT

#1375707 — [PATCH 07/19] mips: get rid of superfluous __GFP_REPEAT

#1375709 — [PATCH 19/19] jbd2: get rid of superfluous __GFP_REPEAT