Commit 24fe1b0e authored Jun 22, 2018 by Will Deacon Committed by Catalin Marinas Jun 27, 2018

arm64: Remove unnecessary ISBs from set_{pte,pmd,pud}



Commit 7f0b1bf0 ("arm64: Fix barriers used for page table modifications")
fixed a reported issue with fixmap page-table entries not being visible
to the walker due to a missing DSB instruction. At the same time, it added
ISB instructions to the arm64 set_{pte,pmd,pud} functions, which are not
required by the architecture and make little sense in isolation.

Remove the redundant ISBs.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

parent 42938868

arch/arm64/include/asm/pgtable.h

+1 −5

Original line number	Diff line number	Diff line
		@@ -224,10 +224,8 @@ static inline void set_pte(pte_t *ptep, pte_t pte)
		* Only if the new pte is valid and kernel, otherwise TLB maintenance
		* or update_mmu_cache() have the necessary barriers.
		*/
		if (pte_valid_not_user(pte)) {
		if (pte_valid_not_user(pte))
		dsb(ishst);
		isb();
		}
		}

		extern void __sync_icache_dcache(pte_t pteval);
		@@ -434,7 +432,6 @@ static inline void set_pmd(pmd_t *pmdp, pmd_t pmd)
		{
		WRITE_ONCE(*pmdp, pmd);
		dsb(ishst);
		isb();
		}

		static inline void pmd_clear(pmd_t *pmdp)
		@@ -485,7 +482,6 @@ static inline void set_pud(pud_t *pudp, pud_t pud)
		{
		WRITE_ONCE(*pudp, pud);
		dsb(ishst);
		isb();
		}

		static inline void pud_clear(pud_t *pudp)