diff options
| author | Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> | 2017-02-09 08:28:20 +0530 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2017-02-15 20:02:40 +1100 |
| commit | f4894b80b1ddfef00d4d2e5c58613ccef358a1b2 (patch) | |
| tree | 2e9fd26b7f3af5fe021b8d4e21bbc58c40d10540 /arch | |
| parent | ca94573b9c69d224e50e1084a2776772f4ea030d (diff) | |
powerpc/mm/radix: Use ptep_get_and_clear_full when clearing pte for full mm
This helps us to do some optimization for application exit case, where we can
skip the DD1 style pte update sequence.
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>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/powerpc/include/asm/book3s/64/pgtable.h | 17 | ||||
| -rw-r--r-- | arch/powerpc/include/asm/book3s/64/radix.h | 23 |
2 files changed, 39 insertions, 1 deletions
diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h index 5905f0ff57d1..fef738229a68 100644 --- a/arch/powerpc/include/asm/book3s/64/pgtable.h +++ b/arch/powerpc/include/asm/book3s/64/pgtable.h @@ -371,6 +371,23 @@ static inline pte_t ptep_get_and_clear(struct mm_struct *mm, return __pte(old); } +#define __HAVE_ARCH_PTEP_GET_AND_CLEAR_FULL +static inline pte_t ptep_get_and_clear_full(struct mm_struct *mm, + unsigned long addr, + pte_t *ptep, int full) +{ + if (full && radix_enabled()) { + /* + * Let's skip the DD1 style pte update here. We know that + * this is a full mm pte clear and hence can be sure there is + * no parallel set_pte. + */ + return radix__ptep_get_and_clear_full(mm, addr, ptep, full); + } + return ptep_get_and_clear(mm, addr, ptep); +} + + static inline void pte_clear(struct mm_struct *mm, unsigned long addr, pte_t * ptep) { diff --git a/arch/powerpc/include/asm/book3s/64/radix.h b/arch/powerpc/include/asm/book3s/64/radix.h index 98c9ab37593c..10a290094af4 100644 --- a/arch/powerpc/include/asm/book3s/64/radix.h +++ b/arch/powerpc/include/asm/book3s/64/radix.h @@ -139,7 +139,7 @@ static inline unsigned long radix__pte_update(struct mm_struct *mm, unsigned long new_pte; - old_pte = __radix_pte_update(ptep, ~0, 0); + old_pte = __radix_pte_update(ptep, ~0ul, 0); /* * new value of pte */ @@ -157,6 +157,27 @@ static inline unsigned long radix__pte_update(struct mm_struct *mm, return old_pte; } +static inline pte_t radix__ptep_get_and_clear_full(struct mm_struct *mm, + unsigned long addr, + pte_t *ptep, int full) +{ + unsigned long old_pte; + + if (full) { + /* + * If we are trying to clear the pte, we can skip + * the DD1 pte update sequence and batch the tlb flush. The + * tlb flush batching is done by mmu gather code. We + * still keep the cmp_xchg update to make sure we get + * correct R/C bit which might be updated via Nest MMU. + */ + old_pte = __radix_pte_update(ptep, ~0ul, 0); + } else + old_pte = radix__pte_update(mm, addr, ptep, ~0ul, 0, 0); + + return __pte(old_pte); +} + /* * Set the dirty and/or accessed bits atomically in a linux PTE, this * function doesn't need to invalidate tlb. |