Re: [PATCH] MIPS: make userspace mapping young by default

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Mon, 8 Feb 2021 18:44:22 +0100 Christophe Leroy <christophe.leroy@xxxxxxxxxx> wrote:

> 
> 
> Le 06/02/2021 à 00:41, Andrew Morton a écrit :
> > On Thu, 4 Feb 2021 16:22:39 +0100 Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx> wrote:
> > 
> >> On Thu, Feb 04, 2021 at 09:39:42AM +0800, Huang Pei wrote:
> >>> MIPS page fault path(except huge page) takes 3 exceptions (1 TLB Miss
> >>> + 2 TLB Invalid), butthe second TLB Invalid exception is just
> >>> triggered by __update_tlb from do_page_fault writing tlb without
> >>> _PAGE_VALID set. With this patch, user space mapping prot is made
> >>> young by default (with both _PAGE_VALID and _PAGE_YOUNG set),
> >>> and it only take 1 TLB Miss + 1 TLB Invalid exception
> >>>
> >>> Remove pte_sw_mkyoung without polluting MM code and make page fault
> >>> delay of MIPS on par with other architecture
> >>>
> >>> Signed-off-by: Huang Pei <huangpei@xxxxxxxxxxx>
> >>> ---
> >>>   arch/mips/mm/cache.c    | 30 ++++++++++++++++--------------
> >>>   include/linux/pgtable.h |  8 --------
> >>>   mm/memory.c             |  3 ---
> >>>   3 files changed, 16 insertions(+), 25 deletions(-)
> >>
> >> Acked-by: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx>
> >>
> >> Andrew, can you take this patch through your tree ?
> > 
> > Sure.  I'll drop Christophe's "mm/memory.c: remove pte_sw_mkyoung()"
> > (https://lkml.kernel.org/r/f302ef92c48d1f08a0459aaee1c568ca11213814.1612345700.git.christophe.leroy@xxxxxxxxxx)
> > in favour of this one.
> > 
> 
> Pitty. My patch was improving page faults on powerpc/32.

How does it do that?  By running pte_mkyoung() for powerpc32?  Such a
change is still valid, isn't it?

> That one is only addressing MIPS.

It cleans up core code nicely, by removing a MIPS wart.  We can still
add a ppc32 wart?

> 
> Any plan to take the series from Nick 
> https://patchwork.kernel.org/project/linux-mm/list/?series=404539 ?

I expect so.  After -rc1, if the churn is settling down and reviewers
are happy enough.





[Index of Archives]     [Linux ARM Kernel]     [Linux ARM]     [Linux Omap]     [Fedora ARM]     [IETF Annouce]     [Bugtraq]     [Linux OMAP]     [Linux MIPS]     [eCos]     [Asterisk Internet PBX]     [Linux API]

  Powered by Linux