* [PATCH] slub: do not put a slab to cpu partial list when cpu_partial is 0 @ 2013-06-19 6:33 Joonsoo Kim 2013-06-19 8:00 ` Wanpeng Li ` (4 more replies) 0 siblings, 5 replies; 11+ messages in thread From: Joonsoo Kim @ 2013-06-19 6:33 UTC (permalink / raw) To: Pekka Enberg Cc: Christoph Lameter, Matt Mackall, linux-mm, linux-kernel, Joonsoo Kim In free path, we don't check number of cpu_partial, so one slab can be linked in cpu partial list even if cpu_partial is 0. To prevent this, we should check number of cpu_partial in put_cpu_partial(). Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> diff --git a/mm/slub.c b/mm/slub.c index 57707f0..7033b4f 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -1955,6 +1955,9 @@ static void put_cpu_partial(struct kmem_cache *s, struct page *page, int drain) int pages; int pobjects; + if (!s->cpu_partial) + return; + do { pages = 0; pobjects = 0; -- 1.7.9.5 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> ^ permalink raw reply related [flat|nested] 11+ messages in thread
* Re: [PATCH] slub: do not put a slab to cpu partial list when cpu_partial is 0 2013-06-19 6:33 [PATCH] slub: do not put a slab to cpu partial list when cpu_partial is 0 Joonsoo Kim @ 2013-06-19 8:00 ` Wanpeng Li 2013-06-19 8:00 ` Wanpeng Li ` (3 subsequent siblings) 4 siblings, 0 replies; 11+ messages in thread From: Wanpeng Li @ 2013-06-19 8:00 UTC (permalink / raw) To: Joonsoo Kim Cc: Pekka Enberg, Christoph Lameter, Matt Mackall, linux-mm, linux-kernel On Wed, Jun 19, 2013 at 03:33:55PM +0900, Joonsoo Kim wrote: >In free path, we don't check number of cpu_partial, so one slab can >be linked in cpu partial list even if cpu_partial is 0. To prevent this, >we should check number of cpu_partial in put_cpu_partial(). > How about skip get_partial entirely? put_cpu_partial is called in two paths, one is during refill cpu partial lists in alloc slow path, the other is in free slow path. And cpu_partial is 0 just in debug mode. - alloc slow path, there is unnecessary to call get_partial since cpu partial lists won't be used in debug mode. - free slow patch, new.inuse won't be true in debug mode which lead to put_cpu_partial won't be called. Regards, Wanpeng Li >Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> > >diff --git a/mm/slub.c b/mm/slub.c >index 57707f0..7033b4f 100644 >--- a/mm/slub.c >+++ b/mm/slub.c >@@ -1955,6 +1955,9 @@ static void put_cpu_partial(struct kmem_cache *s, struct page *page, int drain) > int pages; > int pobjects; > >+ if (!s->cpu_partial) >+ return; >+ > do { > pages = 0; > pobjects = 0; >-- >1.7.9.5 > >-- >To unsubscribe, send a message with 'unsubscribe linux-mm' in >the body to majordomo@kvack.org. For more info on Linux MM, >see: http://www.linux-mm.org/ . >Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> ^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH] slub: do not put a slab to cpu partial list when cpu_partial is 0 2013-06-19 6:33 [PATCH] slub: do not put a slab to cpu partial list when cpu_partial is 0 Joonsoo Kim 2013-06-19 8:00 ` Wanpeng Li @ 2013-06-19 8:00 ` Wanpeng Li [not found] ` <51c1652d.246e320a.4057.ffffed4fSMTPIN_ADDED_BROKEN@mx.google.com> ` (2 subsequent siblings) 4 siblings, 0 replies; 11+ messages in thread From: Wanpeng Li @ 2013-06-19 8:00 UTC (permalink / raw) To: Joonsoo Kim Cc: Pekka Enberg, Christoph Lameter, Matt Mackall, linux-mm, linux-kernel On Wed, Jun 19, 2013 at 03:33:55PM +0900, Joonsoo Kim wrote: >In free path, we don't check number of cpu_partial, so one slab can >be linked in cpu partial list even if cpu_partial is 0. To prevent this, >we should check number of cpu_partial in put_cpu_partial(). > How about skip get_partial entirely? put_cpu_partial is called in two paths, one is during refill cpu partial lists in alloc slow path, the other is in free slow path. And cpu_partial is 0 just in debug mode. - alloc slow path, there is unnecessary to call get_partial since cpu partial lists won't be used in debug mode. - free slow patch, new.inuse won't be true in debug mode which lead to put_cpu_partial won't be called. Regards, Wanpeng Li >Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> > >diff --git a/mm/slub.c b/mm/slub.c >index 57707f0..7033b4f 100644 >--- a/mm/slub.c >+++ b/mm/slub.c >@@ -1955,6 +1955,9 @@ static void put_cpu_partial(struct kmem_cache *s, struct page *page, int drain) > int pages; > int pobjects; > >+ if (!s->cpu_partial) >+ return; >+ > do { > pages = 0; > pobjects = 0; >-- >1.7.9.5 > >-- >To unsubscribe, send a message with 'unsubscribe linux-mm' in >the body to majordomo@kvack.org. For more info on Linux MM, >see: http://www.linux-mm.org/ . >Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> ^ permalink raw reply [flat|nested] 11+ messages in thread
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* Re: [PATCH] slub: do not put a slab to cpu partial list when cpu_partial is 0 [not found] ` <51c1652d.246e320a.4057.ffffed4fSMTPIN_ADDED_BROKEN@mx.google.com> @ 2013-06-19 8:52 ` Joonsoo Kim 2013-06-20 0:26 ` Wanpeng Li ` (2 more replies) 0 siblings, 3 replies; 11+ messages in thread From: Joonsoo Kim @ 2013-06-19 8:52 UTC (permalink / raw) To: Wanpeng Li Cc: Pekka Enberg, Christoph Lameter, Matt Mackall, linux-mm, linux-kernel On Wed, Jun 19, 2013 at 04:00:32PM +0800, Wanpeng Li wrote: > On Wed, Jun 19, 2013 at 03:33:55PM +0900, Joonsoo Kim wrote: > >In free path, we don't check number of cpu_partial, so one slab can > >be linked in cpu partial list even if cpu_partial is 0. To prevent this, > >we should check number of cpu_partial in put_cpu_partial(). > > > > How about skip get_partial entirely? put_cpu_partial is called > in two paths, one is during refill cpu partial lists in alloc > slow path, the other is in free slow path. And cpu_partial is 0 > just in debug mode. > > - alloc slow path, there is unnecessary to call get_partial > since cpu partial lists won't be used in debug mode. > - free slow patch, new.inuse won't be true in debug mode > which lead to put_cpu_partial won't be called. > In debug mode, put_cpu_partial() can't be called already on both path. But, if we assign 0 to cpu_partial via sysfs, put_cpu_partial() will be called on free slow path. On alloc slow path, it can't be called, because following test in get_partial_node() is always failed. available > s->cpu_partial / 2 Thanks. > Regards, > Wanpeng Li > > >Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> > > > >diff --git a/mm/slub.c b/mm/slub.c > >index 57707f0..7033b4f 100644 > >--- a/mm/slub.c > >+++ b/mm/slub.c > >@@ -1955,6 +1955,9 @@ static void put_cpu_partial(struct kmem_cache *s, struct page *page, int drain) > > int pages; > > int pobjects; > > > >+ if (!s->cpu_partial) > >+ return; > >+ > > do { > > pages = 0; > > pobjects = 0; > >-- > >1.7.9.5 > > > >-- > >To unsubscribe, send a message with 'unsubscribe linux-mm' in > >the body to majordomo@kvack.org. For more info on Linux MM, > >see: http://www.linux-mm.org/ . > >Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> > > -- > To unsubscribe, send a message with 'unsubscribe linux-mm' in > the body to majordomo@kvack.org. For more info on Linux MM, > see: http://www.linux-mm.org/ . > Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> ^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH] slub: do not put a slab to cpu partial list when cpu_partial is 0 2013-06-19 8:52 ` Joonsoo Kim @ 2013-06-20 0:26 ` Wanpeng Li 2013-06-20 0:26 ` Wanpeng Li [not found] ` <51c24c29.425c320a.433e.ffff9d8fSMTPIN_ADDED_BROKEN@mx.google.com> 2 siblings, 0 replies; 11+ messages in thread From: Wanpeng Li @ 2013-06-20 0:26 UTC (permalink / raw) To: Joonsoo Kim Cc: Pekka Enberg, Christoph Lameter, Matt Mackall, linux-mm, linux-kernel On Wed, Jun 19, 2013 at 05:52:50PM +0900, Joonsoo Kim wrote: >On Wed, Jun 19, 2013 at 04:00:32PM +0800, Wanpeng Li wrote: >> On Wed, Jun 19, 2013 at 03:33:55PM +0900, Joonsoo Kim wrote: >> >In free path, we don't check number of cpu_partial, so one slab can >> >be linked in cpu partial list even if cpu_partial is 0. To prevent this, >> >we should check number of cpu_partial in put_cpu_partial(). >> > >> >> How about skip get_partial entirely? put_cpu_partial is called >> in two paths, one is during refill cpu partial lists in alloc >> slow path, the other is in free slow path. And cpu_partial is 0 >> just in debug mode. >> >> - alloc slow path, there is unnecessary to call get_partial >> since cpu partial lists won't be used in debug mode. >> - free slow patch, new.inuse won't be true in debug mode >> which lead to put_cpu_partial won't be called. >> > >In debug mode, put_cpu_partial() can't be called already on both path. >But, if we assign 0 to cpu_partial via sysfs, put_cpu_partial() will be called >on free slow path. On alloc slow path, it can't be called, because following >test in get_partial_node() is always failed. > >available > s->cpu_partial / 2 Is it always true? We can freeze slab from partial list, and s->cpu_partial is 0. Regards, Wanpeng Li > >Thanks. > >> Regards, >> Wanpeng Li >> >> >Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> >> > >> >diff --git a/mm/slub.c b/mm/slub.c >> >index 57707f0..7033b4f 100644 >> >--- a/mm/slub.c >> >+++ b/mm/slub.c >> >@@ -1955,6 +1955,9 @@ static void put_cpu_partial(struct kmem_cache *s, struct page *page, int drain) >> > int pages; >> > int pobjects; >> > >> >+ if (!s->cpu_partial) >> >+ return; >> >+ >> > do { >> > pages = 0; >> > pobjects = 0; >> >-- >> >1.7.9.5 >> > >> >-- >> >To unsubscribe, send a message with 'unsubscribe linux-mm' in >> >the body to majordomo@kvack.org. For more info on Linux MM, >> >see: http://www.linux-mm.org/ . >> >Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> >> >> -- >> To unsubscribe, send a message with 'unsubscribe linux-mm' in >> the body to majordomo@kvack.org. For more info on Linux MM, >> see: http://www.linux-mm.org/ . >> Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> ^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH] slub: do not put a slab to cpu partial list when cpu_partial is 0 2013-06-19 8:52 ` Joonsoo Kim 2013-06-20 0:26 ` Wanpeng Li @ 2013-06-20 0:26 ` Wanpeng Li [not found] ` <51c24c29.425c320a.433e.ffff9d8fSMTPIN_ADDED_BROKEN@mx.google.com> 2 siblings, 0 replies; 11+ messages in thread From: Wanpeng Li @ 2013-06-20 0:26 UTC (permalink / raw) To: Joonsoo Kim Cc: Pekka Enberg, Christoph Lameter, Matt Mackall, linux-mm, linux-kernel On Wed, Jun 19, 2013 at 05:52:50PM +0900, Joonsoo Kim wrote: >On Wed, Jun 19, 2013 at 04:00:32PM +0800, Wanpeng Li wrote: >> On Wed, Jun 19, 2013 at 03:33:55PM +0900, Joonsoo Kim wrote: >> >In free path, we don't check number of cpu_partial, so one slab can >> >be linked in cpu partial list even if cpu_partial is 0. To prevent this, >> >we should check number of cpu_partial in put_cpu_partial(). >> > >> >> How about skip get_partial entirely? put_cpu_partial is called >> in two paths, one is during refill cpu partial lists in alloc >> slow path, the other is in free slow path. And cpu_partial is 0 >> just in debug mode. >> >> - alloc slow path, there is unnecessary to call get_partial >> since cpu partial lists won't be used in debug mode. >> - free slow patch, new.inuse won't be true in debug mode >> which lead to put_cpu_partial won't be called. >> > >In debug mode, put_cpu_partial() can't be called already on both path. >But, if we assign 0 to cpu_partial via sysfs, put_cpu_partial() will be called >on free slow path. On alloc slow path, it can't be called, because following >test in get_partial_node() is always failed. > >available > s->cpu_partial / 2 Is it always true? We can freeze slab from partial list, and s->cpu_partial is 0. Regards, Wanpeng Li > >Thanks. > >> Regards, >> Wanpeng Li >> >> >Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> >> > >> >diff --git a/mm/slub.c b/mm/slub.c >> >index 57707f0..7033b4f 100644 >> >--- a/mm/slub.c >> >+++ b/mm/slub.c >> >@@ -1955,6 +1955,9 @@ static void put_cpu_partial(struct kmem_cache *s, struct page *page, int drain) >> > int pages; >> > int pobjects; >> > >> >+ if (!s->cpu_partial) >> >+ return; >> >+ >> > do { >> > pages = 0; >> > pobjects = 0; >> >-- >> >1.7.9.5 >> > >> >-- >> >To unsubscribe, send a message with 'unsubscribe linux-mm' in >> >the body to majordomo@kvack.org. For more info on Linux MM, >> >see: http://www.linux-mm.org/ . >> >Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> >> >> -- >> To unsubscribe, send a message with 'unsubscribe linux-mm' in >> the body to majordomo@kvack.org. For more info on Linux MM, >> see: http://www.linux-mm.org/ . >> Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> ^ permalink raw reply [flat|nested] 11+ messages in thread
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* Re: [PATCH] slub: do not put a slab to cpu partial list when cpu_partial is 0 [not found] ` <51c24c29.425c320a.433e.ffff9d8fSMTPIN_ADDED_BROKEN@mx.google.com> @ 2013-06-20 1:44 ` Joonsoo Kim 2013-06-20 2:32 ` Wanpeng Li 2013-06-20 2:32 ` Wanpeng Li 0 siblings, 2 replies; 11+ messages in thread From: Joonsoo Kim @ 2013-06-20 1:44 UTC (permalink / raw) To: Wanpeng Li Cc: Pekka Enberg, Christoph Lameter, Matt Mackall, linux-mm, linux-kernel On Thu, Jun 20, 2013 at 08:26:03AM +0800, Wanpeng Li wrote: > On Wed, Jun 19, 2013 at 05:52:50PM +0900, Joonsoo Kim wrote: > >On Wed, Jun 19, 2013 at 04:00:32PM +0800, Wanpeng Li wrote: > >> On Wed, Jun 19, 2013 at 03:33:55PM +0900, Joonsoo Kim wrote: > >> >In free path, we don't check number of cpu_partial, so one slab can > >> >be linked in cpu partial list even if cpu_partial is 0. To prevent this, > >> >we should check number of cpu_partial in put_cpu_partial(). > >> > > >> > >> How about skip get_partial entirely? put_cpu_partial is called > >> in two paths, one is during refill cpu partial lists in alloc > >> slow path, the other is in free slow path. And cpu_partial is 0 > >> just in debug mode. > >> > >> - alloc slow path, there is unnecessary to call get_partial > >> since cpu partial lists won't be used in debug mode. > >> - free slow patch, new.inuse won't be true in debug mode > >> which lead to put_cpu_partial won't be called. > >> > > > >In debug mode, put_cpu_partial() can't be called already on both path. > >But, if we assign 0 to cpu_partial via sysfs, put_cpu_partial() will be called > >on free slow path. On alloc slow path, it can't be called, because following > >test in get_partial_node() is always failed. > > > >available > s->cpu_partial / 2 > > Is it always true? We can freeze slab from partial list, and > s->cpu_partial is 0. Do you mean node partial list? At first, acquire_slab() is called for a cpu slab(not cpu partial list) in get_partial_node(), and then, check above test. In this time, available is always higher than 0, so, if we assign 0 to s->cpu_partial, we break the loop and we don't try to get a slab for cpu partial list. Thanks. > > Regards, > Wanpeng Li > > > > >Thanks. > > > >> Regards, > >> Wanpeng Li > >> > >> >Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> > >> > > >> >diff --git a/mm/slub.c b/mm/slub.c > >> >index 57707f0..7033b4f 100644 > >> >--- a/mm/slub.c > >> >+++ b/mm/slub.c > >> >@@ -1955,6 +1955,9 @@ static void put_cpu_partial(struct kmem_cache *s, struct page *page, int drain) > >> > int pages; > >> > int pobjects; > >> > > >> >+ if (!s->cpu_partial) > >> >+ return; > >> >+ > >> > do { > >> > pages = 0; > >> > pobjects = 0; > >> >-- > >> >1.7.9.5 > >> > > >> >-- > >> >To unsubscribe, send a message with 'unsubscribe linux-mm' in > >> >the body to majordomo@kvack.org. For more info on Linux MM, > >> >see: http://www.linux-mm.org/ . > >> >Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> > >> > >> -- > >> To unsubscribe, send a message with 'unsubscribe linux-mm' in > >> the body to majordomo@kvack.org. For more info on Linux MM, > >> see: http://www.linux-mm.org/ . > >> Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> > > -- > To unsubscribe, send a message with 'unsubscribe linux-mm' in > the body to majordomo@kvack.org. For more info on Linux MM, > see: http://www.linux-mm.org/ . > Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> ^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH] slub: do not put a slab to cpu partial list when cpu_partial is 0 2013-06-20 1:44 ` Joonsoo Kim @ 2013-06-20 2:32 ` Wanpeng Li 2013-06-20 2:32 ` Wanpeng Li 1 sibling, 0 replies; 11+ messages in thread From: Wanpeng Li @ 2013-06-20 2:32 UTC (permalink / raw) To: Joonsoo Kim Cc: Pekka Enberg, Christoph Lameter, Matt Mackall, linux-mm, linux-kernel On Thu, Jun 20, 2013 at 10:44:40AM +0900, Joonsoo Kim wrote: >On Thu, Jun 20, 2013 at 08:26:03AM +0800, Wanpeng Li wrote: >> On Wed, Jun 19, 2013 at 05:52:50PM +0900, Joonsoo Kim wrote: >> >On Wed, Jun 19, 2013 at 04:00:32PM +0800, Wanpeng Li wrote: >> >> On Wed, Jun 19, 2013 at 03:33:55PM +0900, Joonsoo Kim wrote: >> >> >In free path, we don't check number of cpu_partial, so one slab can >> >> >be linked in cpu partial list even if cpu_partial is 0. To prevent this, >> >> >we should check number of cpu_partial in put_cpu_partial(). >> >> > >> >> >> >> How about skip get_partial entirely? put_cpu_partial is called >> >> in two paths, one is during refill cpu partial lists in alloc >> >> slow path, the other is in free slow path. And cpu_partial is 0 >> >> just in debug mode. >> >> >> >> - alloc slow path, there is unnecessary to call get_partial >> >> since cpu partial lists won't be used in debug mode. >> >> - free slow patch, new.inuse won't be true in debug mode >> >> which lead to put_cpu_partial won't be called. >> >> >> > >> >In debug mode, put_cpu_partial() can't be called already on both path. >> >But, if we assign 0 to cpu_partial via sysfs, put_cpu_partial() will be called >> >on free slow path. On alloc slow path, it can't be called, because following >> >test in get_partial_node() is always failed. >> > >> >available > s->cpu_partial / 2 >> >> Is it always true? We can freeze slab from partial list, and >> s->cpu_partial is 0. > >Do you mean node partial list? > Yup. >At first, acquire_slab() is called for a cpu slab(not cpu partial list) >in get_partial_node(), and then, check above test. In this time, available >is always higher than 0, so, if we assign 0 to s->cpu_partial, we break >the loop and we don't try to get a slab for cpu partial list. > Agreed. Reviewed-by: Wanpeng Li <liwanp@linux.vnet.ibm.com> >Thanks. > >> >> Regards, >> Wanpeng Li >> >> > >> >Thanks. >> > >> >> Regards, >> >> Wanpeng Li >> >> >> >> >Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> >> >> > >> >> >diff --git a/mm/slub.c b/mm/slub.c >> >> >index 57707f0..7033b4f 100644 >> >> >--- a/mm/slub.c >> >> >+++ b/mm/slub.c >> >> >@@ -1955,6 +1955,9 @@ static void put_cpu_partial(struct kmem_cache *s, struct page *page, int drain) >> >> > int pages; >> >> > int pobjects; >> >> > >> >> >+ if (!s->cpu_partial) >> >> >+ return; >> >> >+ >> >> > do { >> >> > pages = 0; >> >> > pobjects = 0; >> >> >-- >> >> >1.7.9.5 >> >> > >> >> >-- >> >> >To unsubscribe, send a message with 'unsubscribe linux-mm' in >> >> >the body to majordomo@kvack.org. For more info on Linux MM, >> >> >see: http://www.linux-mm.org/ . >> >> >Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> >> >> >> >> -- >> >> To unsubscribe, send a message with 'unsubscribe linux-mm' in >> >> the body to majordomo@kvack.org. For more info on Linux MM, >> >> see: http://www.linux-mm.org/ . >> >> Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> >> >> -- >> To unsubscribe, send a message with 'unsubscribe linux-mm' in >> the body to majordomo@kvack.org. For more info on Linux MM, >> see: http://www.linux-mm.org/ . >> Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> ^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH] slub: do not put a slab to cpu partial list when cpu_partial is 0 2013-06-20 1:44 ` Joonsoo Kim 2013-06-20 2:32 ` Wanpeng Li @ 2013-06-20 2:32 ` Wanpeng Li 1 sibling, 0 replies; 11+ messages in thread From: Wanpeng Li @ 2013-06-20 2:32 UTC (permalink / raw) To: Joonsoo Kim Cc: Pekka Enberg, Christoph Lameter, Matt Mackall, linux-mm, linux-kernel On Thu, Jun 20, 2013 at 10:44:40AM +0900, Joonsoo Kim wrote: >On Thu, Jun 20, 2013 at 08:26:03AM +0800, Wanpeng Li wrote: >> On Wed, Jun 19, 2013 at 05:52:50PM +0900, Joonsoo Kim wrote: >> >On Wed, Jun 19, 2013 at 04:00:32PM +0800, Wanpeng Li wrote: >> >> On Wed, Jun 19, 2013 at 03:33:55PM +0900, Joonsoo Kim wrote: >> >> >In free path, we don't check number of cpu_partial, so one slab can >> >> >be linked in cpu partial list even if cpu_partial is 0. To prevent this, >> >> >we should check number of cpu_partial in put_cpu_partial(). >> >> > >> >> >> >> How about skip get_partial entirely? put_cpu_partial is called >> >> in two paths, one is during refill cpu partial lists in alloc >> >> slow path, the other is in free slow path. And cpu_partial is 0 >> >> just in debug mode. >> >> >> >> - alloc slow path, there is unnecessary to call get_partial >> >> since cpu partial lists won't be used in debug mode. >> >> - free slow patch, new.inuse won't be true in debug mode >> >> which lead to put_cpu_partial won't be called. >> >> >> > >> >In debug mode, put_cpu_partial() can't be called already on both path. >> >But, if we assign 0 to cpu_partial via sysfs, put_cpu_partial() will be called >> >on free slow path. On alloc slow path, it can't be called, because following >> >test in get_partial_node() is always failed. >> > >> >available > s->cpu_partial / 2 >> >> Is it always true? We can freeze slab from partial list, and >> s->cpu_partial is 0. > >Do you mean node partial list? > Yup. >At first, acquire_slab() is called for a cpu slab(not cpu partial list) >in get_partial_node(), and then, check above test. In this time, available >is always higher than 0, so, if we assign 0 to s->cpu_partial, we break >the loop and we don't try to get a slab for cpu partial list. > Agreed. Reviewed-by: Wanpeng Li <liwanp@linux.vnet.ibm.com> >Thanks. > >> >> Regards, >> Wanpeng Li >> >> > >> >Thanks. >> > >> >> Regards, >> >> Wanpeng Li >> >> >> >> >Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> >> >> > >> >> >diff --git a/mm/slub.c b/mm/slub.c >> >> >index 57707f0..7033b4f 100644 >> >> >--- a/mm/slub.c >> >> >+++ b/mm/slub.c >> >> >@@ -1955,6 +1955,9 @@ static void put_cpu_partial(struct kmem_cache *s, struct page *page, int drain) >> >> > int pages; >> >> > int pobjects; >> >> > >> >> >+ if (!s->cpu_partial) >> >> >+ return; >> >> >+ >> >> > do { >> >> > pages = 0; >> >> > pobjects = 0; >> >> >-- >> >> >1.7.9.5 >> >> > >> >> >-- >> >> >To unsubscribe, send a message with 'unsubscribe linux-mm' in >> >> >the body to majordomo@kvack.org. For more info on Linux MM, >> >> >see: http://www.linux-mm.org/ . >> >> >Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> >> >> >> >> -- >> >> To unsubscribe, send a message with 'unsubscribe linux-mm' in >> >> the body to majordomo@kvack.org. For more info on Linux MM, >> >> see: http://www.linux-mm.org/ . >> >> Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> >> >> -- >> To unsubscribe, send a message with 'unsubscribe linux-mm' in >> the body to majordomo@kvack.org. For more info on Linux MM, >> see: http://www.linux-mm.org/ . >> Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> ^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH] slub: do not put a slab to cpu partial list when cpu_partial is 0 2013-06-19 6:33 [PATCH] slub: do not put a slab to cpu partial list when cpu_partial is 0 Joonsoo Kim ` (2 preceding siblings ...) [not found] ` <51c1652d.246e320a.4057.ffffed4fSMTPIN_ADDED_BROKEN@mx.google.com> @ 2013-06-19 14:25 ` Christoph Lameter 2013-07-07 15:47 ` Pekka Enberg 4 siblings, 0 replies; 11+ messages in thread From: Christoph Lameter @ 2013-06-19 14:25 UTC (permalink / raw) To: Joonsoo Kim; +Cc: Pekka Enberg, Matt Mackall, linux-mm, linux-kernel On Wed, 19 Jun 2013, Joonsoo Kim wrote: > In free path, we don't check number of cpu_partial, so one slab can > be linked in cpu partial list even if cpu_partial is 0. To prevent this, > we should check number of cpu_partial in put_cpu_partial(). Acked-by: Christoph Lameeter <cl@linux.com> -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> ^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH] slub: do not put a slab to cpu partial list when cpu_partial is 0 2013-06-19 6:33 [PATCH] slub: do not put a slab to cpu partial list when cpu_partial is 0 Joonsoo Kim ` (3 preceding siblings ...) 2013-06-19 14:25 ` Christoph Lameter @ 2013-07-07 15:47 ` Pekka Enberg 4 siblings, 0 replies; 11+ messages in thread From: Pekka Enberg @ 2013-07-07 15:47 UTC (permalink / raw) To: Joonsoo Kim; +Cc: Christoph Lameter, Matt Mackall, linux-mm@kvack.org, LKML On Wed, Jun 19, 2013 at 9:33 AM, Joonsoo Kim <iamjoonsoo.kim@lge.com> wrote: > In free path, we don't check number of cpu_partial, so one slab can > be linked in cpu partial list even if cpu_partial is 0. To prevent this, > we should check number of cpu_partial in put_cpu_partial(). > > Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Applied, thanks a lot! -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> ^ permalink raw reply [flat|nested] 11+ messages in thread
end of thread, other threads:[~2013-07-07 15:47 UTC | newest] Thread overview: 11+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2013-06-19 6:33 [PATCH] slub: do not put a slab to cpu partial list when cpu_partial is 0 Joonsoo Kim 2013-06-19 8:00 ` Wanpeng Li 2013-06-19 8:00 ` Wanpeng Li [not found] ` <51c1652d.246e320a.4057.ffffed4fSMTPIN_ADDED_BROKEN@mx.google.com> 2013-06-19 8:52 ` Joonsoo Kim 2013-06-20 0:26 ` Wanpeng Li 2013-06-20 0:26 ` Wanpeng Li [not found] ` <51c24c29.425c320a.433e.ffff9d8fSMTPIN_ADDED_BROKEN@mx.google.com> 2013-06-20 1:44 ` Joonsoo Kim 2013-06-20 2:32 ` Wanpeng Li 2013-06-20 2:32 ` Wanpeng Li 2013-06-19 14:25 ` Christoph Lameter 2013-07-07 15:47 ` Pekka Enberg
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