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| author | Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> | 2017-02-09 08:28:19 +0530 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2017-02-15 20:02:40 +1100 |
| commit | ca94573b9c69d224e50e1084a2776772f4ea030d (patch) | |
| tree | 6cbe50dc5a4222c9f289819acb92f13eff5bf01b | |
| parent | 18061c17c8ecdbdbf1e7d1695ec44e7388b4f601 (diff) | |
| download | linux-ca94573b9c69d224e50e1084a2776772f4ea030d.tar.bz2 | |
powerpc/mm/radix: Update pte update sequence for pte clear case
In the kernel we do follow the below sequence in different code paths.
pte = ptep_get_clear(ptep)
....
set_pte_at(ptep, pte)
We do that for mremap, autonuma protection update and softdirty clearing. This
implies our optimization to skip a tlb flush when clearing a pte update is
not valid, because for DD1 system that followup set_pte_at will be done witout
doing the required tlbflush. Fix that by always doing the dd1 style pte update
irrespective of new_pte value. In a later patch we will optimize the application
exit case.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Tested-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| -rw-r--r-- | arch/powerpc/include/asm/book3s/64/radix.h | 12 |
1 files changed, 3 insertions, 9 deletions
diff --git a/arch/powerpc/include/asm/book3s/64/radix.h b/arch/powerpc/include/asm/book3s/64/radix.h index 0032b662284c..98c9ab37593c 100644 --- a/arch/powerpc/include/asm/book3s/64/radix.h +++ b/arch/powerpc/include/asm/book3s/64/radix.h @@ -144,16 +144,10 @@ static inline unsigned long radix__pte_update(struct mm_struct *mm, * new value of pte */ new_pte = (old_pte | set) & ~clr; - /* - * If we are trying to clear the pte, we can skip - * the below sequence and batch the tlb flush. The - * tlb flush batching is done by mmu gather code - */ - if (new_pte) { - asm volatile("ptesync" : : : "memory"); - radix__flush_tlb_pte_p9_dd1(old_pte, mm, addr); + asm volatile("ptesync" : : : "memory"); + radix__flush_tlb_pte_p9_dd1(old_pte, mm, addr); + if (new_pte) __radix_pte_update(ptep, 0, new_pte); - } } else old_pte = __radix_pte_update(ptep, clr, set); asm volatile("ptesync" : : : "memory"); |