From 9b3a53ab76771e3669e50086c131e1574fe25847 Mon Sep 17 00:00:00 2001 From: Stuart Menefy Date: Fri, 24 Nov 2006 11:42:24 +0900 Subject: sh: TLB miss fast-path optimizations. Handle simple TLB miss faults which can be resolved completely from the page table in assembler. Signed-off-by: Stuart Menefy Signed-off-by: Paul Mundt --- arch/sh/mm/Kconfig | 1 + arch/sh/mm/fault.c | 86 ------------------------------------------------------ 2 files changed, 1 insertion(+), 86 deletions(-) (limited to 'arch/sh/mm') diff --git a/arch/sh/mm/Kconfig b/arch/sh/mm/Kconfig index 88e9663fc9f..6cd6d0045d1 100644 --- a/arch/sh/mm/Kconfig +++ b/arch/sh/mm/Kconfig @@ -20,6 +20,7 @@ config CPU_SH4 bool select CPU_HAS_INTEVT select CPU_HAS_SR_RB + select CPU_HAS_PTEA if !CPU_SUBTYPE_ST40 config CPU_SH4A bool diff --git a/arch/sh/mm/fault.c b/arch/sh/mm/fault.c index 128907ef7fc..123fb80c859 100644 --- a/arch/sh/mm/fault.c +++ b/arch/sh/mm/fault.c @@ -223,89 +223,3 @@ do_sigbus: if (!user_mode(regs)) goto no_context; } - -#ifdef CONFIG_SH_STORE_QUEUES -/* - * This is a special case for the SH-4 store queues, as pages for this - * space still need to be faulted in before it's possible to flush the - * store queue cache for writeout to the remapped region. - */ -#define P3_ADDR_MAX (P4SEG_STORE_QUE + 0x04000000) -#else -#define P3_ADDR_MAX P4SEG -#endif - -/* - * Called with interrupts disabled. - */ -asmlinkage int __kprobes __do_page_fault(struct pt_regs *regs, - unsigned long writeaccess, - unsigned long address) -{ - pgd_t *pgd; - pud_t *pud; - pmd_t *pmd; - pte_t *pte; - pte_t entry; - struct mm_struct *mm = current->mm; - spinlock_t *ptl; - int ret = 1; - -#ifdef CONFIG_SH_KGDB - if (kgdb_nofault && kgdb_bus_err_hook) - kgdb_bus_err_hook(); -#endif - - /* - * We don't take page faults for P1, P2, and parts of P4, these - * are always mapped, whether it be due to legacy behaviour in - * 29-bit mode, or due to PMB configuration in 32-bit mode. - */ - if (address >= P3SEG && address < P3_ADDR_MAX) { - pgd = pgd_offset_k(address); - mm = NULL; - } else { - if (unlikely(address >= TASK_SIZE || !mm)) - return 1; - - pgd = pgd_offset(mm, address); - } - - pud = pud_offset(pgd, address); - if (pud_none_or_clear_bad(pud)) - return 1; - pmd = pmd_offset(pud, address); - if (pmd_none_or_clear_bad(pmd)) - return 1; - - if (mm) - pte = pte_offset_map_lock(mm, pmd, address, &ptl); - else - pte = pte_offset_kernel(pmd, address); - - entry = *pte; - if (unlikely(pte_none(entry) || pte_not_present(entry))) - goto unlock; - if (unlikely(writeaccess && !pte_write(entry))) - goto unlock; - - if (writeaccess) - entry = pte_mkdirty(entry); - entry = pte_mkyoung(entry); - -#ifdef CONFIG_CPU_SH4 - /* - * ITLB is not affected by "ldtlb" instruction. - * So, we need to flush the entry by ourselves. - */ - __flush_tlb_page(get_asid(), address & PAGE_MASK); -#endif - - set_pte(pte, entry); - update_mmu_cache(NULL, address, entry); - ret = 0; -unlock: - if (mm) - pte_unmap_unlock(pte, ptl); - return ret; -} -- cgit v1.2.3-70-g09d2