Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1609476

Re: [v2 5/5] mm: teach platforms not to zero struct pages memory

Show all headers | View raw

On Fri, Mar 24, 2017 at 03:19:52PM -0400, Pavel Tatashin wrote:
> If we are using deferred struct page initialization feature, most of
> "struct page"es are getting initialized after other CPUs are started, and
> hence we are benefiting from doing this job in parallel. However, we are
> still zeroing all the memory that is allocated for "struct pages" using the
> boot CPU.  This patch solves this problem, by deferring zeroing "struct
> pages" to only when they are initialized.
> 
> Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
> Reviewed-by: Shannon Nelson <shannon.nelson@oracle.com>
> ---
>  arch/powerpc/mm/init_64.c |    2 +-
>  arch/s390/mm/vmem.c       |    2 +-
>  arch/sparc/mm/init_64.c   |    2 +-
>  arch/x86/mm/init_64.c     |    2 +-
>  4 files changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/arch/powerpc/mm/init_64.c b/arch/powerpc/mm/init_64.c
> index eb4c270..24faf2d 100644
> --- a/arch/powerpc/mm/init_64.c
> +++ b/arch/powerpc/mm/init_64.c
> @@ -181,7 +181,7 @@ int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node)
>  		if (vmemmap_populated(start, page_size))
>  			continue;
> 
> -		p = vmemmap_alloc_block(page_size, node, true);
> +		p = vmemmap_alloc_block(page_size, node, VMEMMAP_ZERO);
>  		if (!p)
>  			return -ENOMEM;
> 
> diff --git a/arch/s390/mm/vmem.c b/arch/s390/mm/vmem.c
> index 9c75214..ffe9ba1 100644
> --- a/arch/s390/mm/vmem.c
> +++ b/arch/s390/mm/vmem.c
> @@ -252,7 +252,7 @@ int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node)
>  				void *new_page;
> 
>  				new_page = vmemmap_alloc_block(PMD_SIZE, node,
> -							       true);
> +							       VMEMMAP_ZERO);
>  				if (!new_page)
>  					goto out;
>  				pmd_val(*pm_dir) = __pa(new_page) | sgt_prot;

s390 has two call sites that need to be converted, like you did in one of
your previous patches. The same seems to be true for powerpc, unless there
is a reason to not convert them?

Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

[v2 0/5] parallelized "struct page" zeroing Pavel Tatashin <pasha.tatashin@oracle.com> - 2017-03-24 20:30 +0100
  [v2 2/5] mm: defining memblock_virt_alloc_try_nid_raw Pavel Tatashin <pasha.tatashin@oracle.com> - 2017-03-24 20:30 +0100
  [v2 5/5] mm: teach platforms not to zero struct pages memory Pavel Tatashin <pasha.tatashin@oracle.com> - 2017-03-24 20:30 +0100
    Re: [v2 5/5] mm: teach platforms not to zero struct pages memory Heiko Carstens <heiko.carstens@de.ibm.com> - 2017-03-27 08:10 +0200
  Re: [v2 0/5] parallelized "struct page" zeroing Matthew Wilcox <willy@infradead.org> - 2017-03-25 22:30 +0100

csiph-web