2008-03-21 06:24:00

by Christoph Lameter

Subject: [14/14] vcompound: Avoid vmalloc for ehash_locks

Avoid the use of vmalloc for the ehash locks.

Signed-off-by: Christoph Lameter <[email protected]>

---
include/net/inet_hashtables.h | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

Index: linux-2.6.25-rc5-mm1/include/net/inet_hashtables.h
===================================================================
--- linux-2.6.25-rc5-mm1.orig/include/net/inet_hashtables.h 2008-03-20 22:21:02.680501729 -0700
+++ linux-2.6.25-rc5-mm1/include/net/inet_hashtables.h 2008-03-20 22:22:15.416565317 -0700
@@ -164,7 +164,8 @@ static inline int inet_ehash_locks_alloc
if (sizeof(rwlock_t) != 0) {
#ifdef CONFIG_NUMA
if (size * sizeof(rwlock_t) > PAGE_SIZE)
- hashinfo->ehash_locks = vmalloc(size * sizeof(rwlock_t));
+ hashinfo->ehash_locks = __alloc_vcompound(GFP_KERNEL,
+ get_order(size * sizeof(rwlock_t)));
else
#endif
hashinfo->ehash_locks = kmalloc(size * sizeof(rwlock_t),
@@ -185,7 +186,7 @@ static inline void inet_ehash_locks_free
unsigned int size = (hashinfo->ehash_locks_mask + 1) *
sizeof(rwlock_t);
if (size > PAGE_SIZE)
- vfree(hashinfo->ehash_locks);
+ __free_vcompound(hashinfo->ehash_locks);
else
#endif
kfree(hashinfo->ehash_locks);

--

2008-03-21 07:02:42

by Eric Dumazet

Subject: Re: [14/14] vcompound: Avoid vmalloc for ehash_locks

Christoph Lameter a ?crit :
> Avoid the use of vmalloc for the ehash locks.
>
> Signed-off-by: Christoph Lameter <[email protected]>
>
> ---
> include/net/inet_hashtables.h | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> Index: linux-2.6.25-rc5-mm1/include/net/inet_hashtables.h
> ===================================================================
> --- linux-2.6.25-rc5-mm1.orig/include/net/inet_hashtables.h 2008-03-20 22:21:02.680501729 -0700
> +++ linux-2.6.25-rc5-mm1/include/net/inet_hashtables.h 2008-03-20 22:22:15.416565317 -0700
> @@ -164,7 +164,8 @@ static inline int inet_ehash_locks_alloc
> if (sizeof(rwlock_t) != 0) {
> #ifdef CONFIG_NUMA
> if (size * sizeof(rwlock_t) > PAGE_SIZE)
> - hashinfo->ehash_locks = vmalloc(size * sizeof(rwlock_t));
> + hashinfo->ehash_locks = __alloc_vcompound(GFP_KERNEL,
> + get_order(size * sizeof(rwlock_t)));
> else
> #endif
> hashinfo->ehash_locks = kmalloc(size * sizeof(rwlock_t),
> @@ -185,7 +186,7 @@ static inline void inet_ehash_locks_free
> unsigned int size = (hashinfo->ehash_locks_mask + 1) *
> sizeof(rwlock_t);
> if (size > PAGE_SIZE)
> - vfree(hashinfo->ehash_locks);
> + __free_vcompound(hashinfo->ehash_locks);
> else
> #endif
> kfree(hashinfo->ehash_locks);
>

But, isnt it defeating the purpose of this *particular* vmalloc() use ?

CONFIG_NUMA and vmalloc() at boot time means :

Try to distribute the pages on several nodes.

Memory pressure on ehash_locks[] is so high we definitly want to spread it.

(for similar uses of vmalloc(), see also hashdist=1 )

Also, please CC netdev for network patches :)

Thank you

2008-03-21 07:05:32

by Christoph Lameter

Subject: Re: [14/14] vcompound: Avoid vmalloc for ehash_locks

On Fri, 21 Mar 2008, Eric Dumazet wrote:

> But, isnt it defeating the purpose of this *particular* vmalloc() use ?

I thought that was controlled by hashdist? I did not see it used here and
so I assumed that the RR was not intended here.

2008-03-21 07:31:01

by David Miller

Subject: Re: [14/14] vcompound: Avoid vmalloc for ehash_locks

From: Eric Dumazet <[email protected]>
Date: Fri, 21 Mar 2008 08:02:11 +0100

> But, isnt it defeating the purpose of this *particular* vmalloc() use ?
>
> CONFIG_NUMA and vmalloc() at boot time means :
>
> Try to distribute the pages on several nodes.
>
> Memory pressure on ehash_locks[] is so high we definitly want to spread it.
>
> (for similar uses of vmalloc(), see also hashdist=1 )
>
> Also, please CC netdev for network patches :)

I agree with Eric, converting any of the networking hash
allocations to this new facility is not the right thing
to do.

2008-03-21 07:31:27

by David Miller

Subject: Re: [14/14] vcompound: Avoid vmalloc for ehash_locks

From: Christoph Lameter <[email protected]>
Date: Fri, 21 Mar 2008 00:03:51 -0700 (PDT)

> On Fri, 21 Mar 2008, Eric Dumazet wrote:
>
> > But, isnt it defeating the purpose of this *particular* vmalloc() use ?
>
> I thought that was controlled by hashdist? I did not see it used here and
> so I assumed that the RR was not intended here.

It's intended for all of the major networking hash tables.

2008-03-21 07:42:23

by Eric Dumazet

Subject: Re: [14/14] vcompound: Avoid vmalloc for ehash_locks

David Miller a ?crit :
> From: Christoph Lameter <[email protected]>
> Date: Fri, 21 Mar 2008 00:03:51 -0700 (PDT)
>
>> On Fri, 21 Mar 2008, Eric Dumazet wrote:
>>
>>> But, isnt it defeating the purpose of this *particular* vmalloc() use ?
>> I thought that was controlled by hashdist? I did not see it used here and
>> so I assumed that the RR was not intended here.
>
> It's intended for all of the major networking hash tables.

Other networking hash tables uses alloc_large_system_hash(), which handles
hashdist settings.

But this helper is __init only, so we can not use it for ehash_locks (can be
allocated by DCCP module)

2008-03-21 17:33:25

by Christoph Lameter

Subject: Re: [14/14] vcompound: Avoid vmalloc for ehash_locks

On Fri, 21 Mar 2008, David Miller wrote:

> I agree with Eric, converting any of the networking hash
> allocations to this new facility is not the right thing
> to do.

Ok. Going to drop it.