Re: [RFC PATCH] powerpc/book3s64/radix: Upgrade va tlbie to PID tlbie if we cross PMD_SIZE

2021-08-16 Thread Michael Ellerman
"Aneesh Kumar K.V" writes: > On 8/12/21 6:19 PM, Michael Ellerman wrote: >> "Puvichakravarthy Ramachandran" writes: With shared mapping, even though we are unmapping a large range, the kernel will force a TLB flush with ptl lock held to avoid the race mentioned in commit

Re: [RFC PATCH] powerpc/book3s64/radix: Upgrade va tlbie to PID tlbie if we cross PMD_SIZE

2021-08-12 Thread Aneesh Kumar K.V
On 8/12/21 6:19 PM, Michael Ellerman wrote: "Puvichakravarthy Ramachandran" writes: With shared mapping, even though we are unmapping a large range, the kernel will force a TLB flush with ptl lock held to avoid the race mentioned in commit 1cf35d47712d ("mm: split 'tlb_flush_mmu()' into tlb

Re: [RFC PATCH] powerpc/book3s64/radix: Upgrade va tlbie to PID tlbie if we cross PMD_SIZE

2021-08-12 Thread Michael Ellerman
"Puvichakravarthy Ramachandran" writes: >> With shared mapping, even though we are unmapping a large range, the kernel >> will force a TLB flush with ptl lock held to avoid the race mentioned in >> commit 1cf35d47712d ("mm: split 'tlb_flush_mmu()' into tlb flushing and >> memory freeing parts")

Re: [RFC PATCH] powerpc/book3s64/radix: Upgrade va tlbie to PID tlbie if we cross PMD_SIZE

2021-08-06 Thread Puvichakravarthy Ramachandran
> With shared mapping, even though we are unmapping a large range, the kernel > will force a TLB flush with ptl lock held to avoid the race mentioned in > commit 1cf35d47712d ("mm: split 'tlb_flush_mmu()' into tlb flushing and memory freeing parts") > This results in the kernel issuing a high

Re: [RFC PATCH] powerpc/book3s64/radix: Upgrade va tlbie to PID tlbie if we cross PMD_SIZE

2021-08-06 Thread Puvichakravarthy Ramachandran
> With shared mapping, even though we are unmapping a large range, the kernel > will force a TLB flush with ptl lock held to avoid the race mentioned in > commit 1cf35d47712d ("mm: split 'tlb_flush_mmu()' into tlb flushing and memory freeing parts") > This results in the kernel issuing a high

Re: [RFC PATCH] powerpc/book3s64/radix: Upgrade va tlbie to PID tlbie if we cross PMD_SIZE

2021-08-04 Thread Peter Zijlstra
On Wed, Aug 04, 2021 at 04:39:44PM +1000, Nicholas Piggin wrote: > For that matter, I wonder if we shouldn't do something like this > (untested) so the low level batch flush has visibility to the high > level flush range. > > x86 could use this too AFAIKS, just needs to pass the range a bit >

Re: [RFC PATCH] powerpc/book3s64/radix: Upgrade va tlbie to PID tlbie if we cross PMD_SIZE

2021-08-04 Thread Michael Ellerman
Nicholas Piggin writes: > Excerpts from Aneesh Kumar K.V's message of August 4, 2021 12:37 am: >> With shared mapping, even though we are unmapping a large range, the kernel >> will force a TLB flush with ptl lock held to avoid the race mentioned in >> commit 1cf35d47712d ("mm: split

Re: [RFC PATCH] powerpc/book3s64/radix: Upgrade va tlbie to PID tlbie if we cross PMD_SIZE

2021-08-04 Thread Nicholas Piggin
Excerpts from Nicholas Piggin's message of August 4, 2021 3:14 pm: > Excerpts from Aneesh Kumar K.V's message of August 4, 2021 12:37 am: >> With shared mapping, even though we are unmapping a large range, the kernel >> will force a TLB flush with ptl lock held to avoid the race mentioned in >>

Re: [RFC PATCH] powerpc/book3s64/radix: Upgrade va tlbie to PID tlbie if we cross PMD_SIZE

2021-08-03 Thread Nicholas Piggin
Excerpts from Aneesh Kumar K.V's message of August 4, 2021 12:37 am: > With shared mapping, even though we are unmapping a large range, the kernel > will force a TLB flush with ptl lock held to avoid the race mentioned in > commit 1cf35d47712d ("mm: split 'tlb_flush_mmu()' into tlb flushing and >

[RFC PATCH] powerpc/book3s64/radix: Upgrade va tlbie to PID tlbie if we cross PMD_SIZE

2021-08-03 Thread Aneesh Kumar K.V
With shared mapping, even though we are unmapping a large range, the kernel will force a TLB flush with ptl lock held to avoid the race mentioned in commit 1cf35d47712d ("mm: split 'tlb_flush_mmu()' into tlb flushing and memory freeing parts") This results in the kernel issuing a high number of