From 923f7f6970bd448b8e88b9e4be10fd01fc7106a4 Mon Sep 17 00:00:00 2001 From: Jack Steiner Date: Wed, 15 Oct 2008 22:05:13 -0700 Subject: GRU driver: minor updates A few minor updates for the GRU driver. - documentation changes found in code reviews - changes to #ifdefs to make them recognized by "unifdef" (used in simulator testing) - change GRU context load/unload to prefetch data [akpm@linux-foundation.org: fix typo in comment] Signed-off-by: Jack Steiner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/misc/sgi-gru/grufault.c | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) (limited to 'drivers/misc/sgi-gru/grufault.c') diff --git a/drivers/misc/sgi-gru/grufault.c b/drivers/misc/sgi-gru/grufault.c index 3d33015bbf31..8c389d606c30 100644 --- a/drivers/misc/sgi-gru/grufault.c +++ b/drivers/misc/sgi-gru/grufault.c @@ -214,12 +214,14 @@ static int non_atomic_pte_lookup(struct vm_area_struct *vma, } /* - * * atomic_pte_lookup * * Convert a user virtual address to a physical address * Only supports Intel large pages (2MB only) on x86_64. * ZZZ - hugepage support is incomplete + * + * NOTE: mmap_sem is already held on entry to this function. This + * guarantees existence of the page tables. */ static int atomic_pte_lookup(struct vm_area_struct *vma, unsigned long vaddr, int write, unsigned long *paddr, int *pageshift) @@ -229,9 +231,6 @@ static int atomic_pte_lookup(struct vm_area_struct *vma, unsigned long vaddr, pud_t *pudp; pte_t pte; - WARN_ON(irqs_disabled()); /* ZZZ debug */ - - local_irq_disable(); pgdp = pgd_offset(vma->vm_mm, vaddr); if (unlikely(pgd_none(*pgdp))) goto err; @@ -250,8 +249,6 @@ static int atomic_pte_lookup(struct vm_area_struct *vma, unsigned long vaddr, #endif pte = *pte_offset_kernel(pmdp, vaddr); - local_irq_enable(); - if (unlikely(!pte_present(pte) || (write && (!pte_write(pte) || !pte_dirty(pte))))) return 1; @@ -324,6 +321,7 @@ static int gru_try_dropin(struct gru_thread_state *gts, * Atomic lookup is faster & usually works even if called in non-atomic * context. */ + rmb(); /* Must/check ms_range_active before loading PTEs */ ret = atomic_pte_lookup(vma, vaddr, write, &paddr, &pageshift); if (ret) { if (!cb) @@ -543,6 +541,7 @@ int gru_get_exception_detail(unsigned long arg) ucbnum = get_cb_number((void *)excdet.cb); cbrnum = thread_cbr_number(gts, ucbnum); cbe = get_cbe_by_index(gts->ts_gru, cbrnum); + prefetchw(cbe); /* Harmless on hardware, required for emulator */ excdet.opc = cbe->opccpy; excdet.exopc = cbe->exopccpy; excdet.ecause = cbe->ecause; -- cgit v1.2.3