Re: [PATCH 2/2] powerpc/mm: don't do tlbie for updatepp request with NO HPTE fault

2014-12-01 Thread Aneesh Kumar K.V
Michael Ellerman writes: > On Mon, 2014-11-03 at 20:21 +0530, Aneesh Kumar K.V wrote: >> upatepp get called for a nohpte fault, when we find from the linux >> page table that the translation was hashed before. In that case >> we are sure that there is no existing translation, hence we could >> av

Re: [PATCH 2/2] powerpc/mm: don't do tlbie for updatepp request with NO HPTE fault

2014-12-01 Thread Aneesh Kumar K.V
Benjamin Herrenschmidt writes: > On Mon, 2014-11-03 at 20:21 +0530, Aneesh Kumar K.V wrote: >> --- a/arch/powerpc/mm/hash_native_64.c >> +++ b/arch/powerpc/mm/hash_native_64.c >> @@ -283,11 +283,11 @@ static long native_hpte_remove(unsigned long >> hpte_group) >> >> static long native_hpte_up

Re: [PATCH 2/2] powerpc/mm: don't do tlbie for updatepp request with NO HPTE fault

2014-12-01 Thread Aneesh Kumar K.V
Benjamin Herrenschmidt writes: > On Mon, 2014-11-03 at 20:21 +0530, Aneesh Kumar K.V wrote: >> upatepp get called for a nohpte fault, when we find from the linux >> page table that the translation was hashed before. In that case >> we are sure that there is no existing translation, hence we could

Re: [PATCH 2/2] powerpc/mm: don't do tlbie for updatepp request with NO HPTE fault

2014-12-01 Thread Benjamin Herrenschmidt
On Mon, 2014-11-03 at 20:21 +0530, Aneesh Kumar K.V wrote: > upatepp get called for a nohpte fault, when we find from the linux > page table that the translation was hashed before. In that case > we are sure that there is no existing translation, hence we could > avoid doing tlbie. You need to tes

Re: [PATCH 2/2] powerpc/mm: don't do tlbie for updatepp request with NO HPTE fault

2014-12-01 Thread Michael Ellerman
On Mon, 2014-11-03 at 20:21 +0530, Aneesh Kumar K.V wrote: > upatepp get called for a nohpte fault, when we find from the linux > page table that the translation was hashed before. In that case > we are sure that there is no existing translation, hence we could > avoid doing tlbie. We are sure the

Re: [PATCH 2/2] powerpc/mm: don't do tlbie for updatepp request with NO HPTE fault

2014-12-01 Thread Benjamin Herrenschmidt
On Mon, 2014-11-03 at 20:21 +0530, Aneesh Kumar K.V wrote: > --- a/arch/powerpc/mm/hash_native_64.c > +++ b/arch/powerpc/mm/hash_native_64.c > @@ -283,11 +283,11 @@ static long native_hpte_remove(unsigned long hpte_group) > > static long native_hpte_updatepp(unsigned long slot, unsigned long new

[PATCH 2/2] powerpc/mm: don't do tlbie for updatepp request with NO HPTE fault

2014-11-03 Thread Aneesh Kumar K.V
upatepp get called for a nohpte fault, when we find from the linux page table that the translation was hashed before. In that case we are sure that there is no existing translation, hence we could avoid doing tlbie. Performance number: We use randbox_access_bench written by Anton. Kernel with THP