From ee39b37b23da0b6ec53a8ebe90ff41c016f8ae27 Mon Sep 17 00:00:00 2001 From: Hugh Dickins Date: Tue, 19 Apr 2005 13:29:15 -0700 Subject: [PATCH] freepgt: remove MM_VM_SIZE(mm) There's only one usage of MM_VM_SIZE(mm) left, and it's a troublesome macro because mm doesn't contain the (32-bit emulation?) info needed. But it too is only needed because we ignore the end from the vma list. We could make flush_pgtables return that end, or unmap_vmas. Choose the latter, since it's a natural fit with unmap_mapping_range_vma needing to know its restart addr. This does make more than minimal change, but if unmap_vmas had returned the end before, this is how we'd have done it, rather than storing the break_addr in zap_details. unmap_vmas used to return count of vmas scanned, but that's just debug which hasn't been useful in a while; and if we want the map_count 0 on exit check back, it can easily come from the final remove_vm_struct loop. Signed-off-by: Hugh Dickins Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/memory.c | 28 +++++++++++++--------------- 1 file changed, 13 insertions(+), 15 deletions(-) (limited to 'mm/memory.c') diff --git a/mm/memory.c b/mm/memory.c index fee5dc8fc36c..854bd90eeca1 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -645,7 +645,7 @@ static void unmap_page_range(struct mmu_gather *tlb, struct vm_area_struct *vma, * @nr_accounted: Place number of unmapped pages in vm-accountable vma's here * @details: details of nonlinear truncation or shared cache invalidation * - * Returns the number of vma's which were covered by the unmapping. + * Returns the end address of the unmapping (restart addr if interrupted). * * Unmap all pages in the vma list. Called under page_table_lock. * @@ -662,7 +662,7 @@ static void unmap_page_range(struct mmu_gather *tlb, struct vm_area_struct *vma, * ensure that any thus-far unmapped pages are flushed before unmap_vmas() * drops the lock and schedules. */ -int unmap_vmas(struct mmu_gather **tlbp, struct mm_struct *mm, +unsigned long unmap_vmas(struct mmu_gather **tlbp, struct mm_struct *mm, struct vm_area_struct *vma, unsigned long start_addr, unsigned long end_addr, unsigned long *nr_accounted, struct zap_details *details) @@ -670,12 +670,11 @@ int unmap_vmas(struct mmu_gather **tlbp, struct mm_struct *mm, unsigned long zap_bytes = ZAP_BLOCK_SIZE; unsigned long tlb_start = 0; /* For tlb_finish_mmu */ int tlb_start_valid = 0; - int ret = 0; + unsigned long start = start_addr; spinlock_t *i_mmap_lock = details? details->i_mmap_lock: NULL; int fullmm = tlb_is_full_mm(*tlbp); for ( ; vma && vma->vm_start < end_addr; vma = vma->vm_next) { - unsigned long start; unsigned long end; start = max(vma->vm_start, start_addr); @@ -688,7 +687,6 @@ int unmap_vmas(struct mmu_gather **tlbp, struct mm_struct *mm, if (vma->vm_flags & VM_ACCOUNT) *nr_accounted += (end - start) >> PAGE_SHIFT; - ret++; while (start != end) { unsigned long block; @@ -719,7 +717,6 @@ int unmap_vmas(struct mmu_gather **tlbp, struct mm_struct *mm, if (i_mmap_lock) { /* must reset count of rss freed */ *tlbp = tlb_gather_mmu(mm, fullmm); - details->break_addr = start; goto out; } spin_unlock(&mm->page_table_lock); @@ -733,7 +730,7 @@ int unmap_vmas(struct mmu_gather **tlbp, struct mm_struct *mm, } } out: - return ret; + return start; /* which is now the end (or restart) address */ } /** @@ -743,7 +740,7 @@ out: * @size: number of bytes to zap * @details: details of nonlinear truncation or shared cache invalidation */ -void zap_page_range(struct vm_area_struct *vma, unsigned long address, +unsigned long zap_page_range(struct vm_area_struct *vma, unsigned long address, unsigned long size, struct zap_details *details) { struct mm_struct *mm = vma->vm_mm; @@ -753,15 +750,16 @@ void zap_page_range(struct vm_area_struct *vma, unsigned long address, if (is_vm_hugetlb_page(vma)) { zap_hugepage_range(vma, address, size); - return; + return end; } lru_add_drain(); spin_lock(&mm->page_table_lock); tlb = tlb_gather_mmu(mm, 0); - unmap_vmas(&tlb, mm, vma, address, end, &nr_accounted, details); + end = unmap_vmas(&tlb, mm, vma, address, end, &nr_accounted, details); tlb_finish_mmu(tlb, address, end); spin_unlock(&mm->page_table_lock); + return end; } /* @@ -1348,7 +1346,7 @@ no_new_page: * i_mmap_lock. * * In order to make forward progress despite repeatedly restarting some - * large vma, note the break_addr set by unmap_vmas when it breaks out: + * large vma, note the restart_addr from unmap_vmas when it breaks out: * and restart from that address when we reach that vma again. It might * have been split or merged, shrunk or extended, but never shifted: so * restart_addr remains valid so long as it remains in the vma's range. @@ -1386,8 +1384,8 @@ again: } } - details->break_addr = end_addr; - zap_page_range(vma, start_addr, end_addr - start_addr, details); + restart_addr = zap_page_range(vma, start_addr, + end_addr - start_addr, details); /* * We cannot rely on the break test in unmap_vmas: @@ -1398,14 +1396,14 @@ again: need_break = need_resched() || need_lockbreak(details->i_mmap_lock); - if (details->break_addr >= end_addr) { + if (restart_addr >= end_addr) { /* We have now completed this vma: mark it so */ vma->vm_truncate_count = details->truncate_count; if (!need_break) return 0; } else { /* Note restart_addr in vma's truncate_count field */ - vma->vm_truncate_count = details->break_addr; + vma->vm_truncate_count = restart_addr; if (!need_break) goto again; } -- cgit