diff options
author | Vineet Gupta <vgupta@kernel.org> | 2020-01-13 09:16:06 -0800 |
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committer | Vineet Gupta <vgupta@kernel.org> | 2021-08-24 14:25:48 -0700 |
commit | 6128df5be48f48d63efdc7c52022dd163f612373 (patch) | |
tree | 8d740e544f2125984b51b048e15042d226f9c995 /arch/arc/include/asm/pgtable.h | |
parent | ARC: retire MMUv1 and MMUv2 support (diff) | |
download | linux-dev-6128df5be48f48d63efdc7c52022dd163f612373.tar.xz linux-dev-6128df5be48f48d63efdc7c52022dd163f612373.zip |
ARC: mm: use SCRATCH_DATA0 register for caching pgdir in ARCv2 only
MMU SCRATCH_DATA0 register is intended to cache task pgd. However in
ARC700 SMP port, it has to be repurposed for re-entrant interrupt
handling, while UP port doesn't. We currently handle these use-cases
using a fabricated #define which has usual issues of dependency nesting
and obvious ugliness.
So clean this up: for ARC700 don't use to cache pgd (even in UP) and do
the opposite for ARCv2.
And while here, switch to canonical pgd_offset().
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Vineet Gupta <vgupta@kernel.org>
Diffstat (limited to 'arch/arc/include/asm/pgtable.h')
-rw-r--r-- | arch/arc/include/asm/pgtable.h | 23 |
1 files changed, 0 insertions, 23 deletions
diff --git a/arch/arc/include/asm/pgtable.h b/arch/arc/include/asm/pgtable.h index 0c3e220bd2b4..80b57c14b430 100644 --- a/arch/arc/include/asm/pgtable.h +++ b/arch/arc/include/asm/pgtable.h @@ -284,29 +284,6 @@ static inline void set_pte_at(struct mm_struct *mm, unsigned long addr, set_pte(ptep, pteval); } -/* - * Macro to quickly access the PGD entry, utlising the fact that some - * arch may cache the pointer to Page Directory of "current" task - * in a MMU register - * - * Thus task->mm->pgd (3 pointer dereferences, cache misses etc simply - * becomes read a register - * - * ********CAUTION*******: - * Kernel code might be dealing with some mm_struct of NON "current" - * Thus use this macro only when you are certain that "current" is current - * e.g. when dealing with signal frame setup code etc - */ -#ifdef ARC_USE_SCRATCH_REG -#define pgd_offset_fast(mm, addr) \ -({ \ - pgd_t *pgd_base = (pgd_t *) read_aux_reg(ARC_REG_SCRATCH_DATA0); \ - pgd_base + pgd_index(addr); \ -}) -#else -#define pgd_offset_fast(mm, addr) pgd_offset(mm, addr) -#endif - extern pgd_t swapper_pg_dir[] __aligned(PAGE_SIZE); void update_mmu_cache(struct vm_area_struct *vma, unsigned long address, pte_t *ptep); |