The patch titled nommu: struct vm_region's vm_usage count need not be atomic has been removed from the -mm tree. Its filename was nommu-struct-vm_regions-vm_usage-count-need-not-be-atomic.patch This patch was dropped because it was merged into mainline or a subsystem tree The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ Subject: nommu: struct vm_region's vm_usage count need not be atomic From: David Howells <dhowells@xxxxxxxxxx> The vm_usage count field in struct vm_region does not need to be atomic as it's only even modified whilst nommu_region_sem is write locked. Signed-off-by: David Howells <dhowells@xxxxxxxxxx> Acked-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx> Cc: Greg Ungerer <gerg@xxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/linux/mm_types.h | 2 +- mm/nommu.c | 14 +++++++------- 2 files changed, 8 insertions(+), 8 deletions(-) diff -puN include/linux/mm_types.h~nommu-struct-vm_regions-vm_usage-count-need-not-be-atomic include/linux/mm_types.h --- a/include/linux/mm_types.h~nommu-struct-vm_regions-vm_usage-count-need-not-be-atomic +++ a/include/linux/mm_types.h @@ -122,7 +122,7 @@ struct vm_region { unsigned long vm_pgoff; /* the offset in vm_file corresponding to vm_start */ struct file *vm_file; /* the backing file or NULL */ - atomic_t vm_usage; /* region usage count */ + int vm_usage; /* region usage count (access under nommu_region_sem) */ bool vm_icache_flushed : 1; /* true if the icache has been flushed for * this region */ }; diff -puN mm/nommu.c~nommu-struct-vm_regions-vm_usage-count-need-not-be-atomic mm/nommu.c --- a/mm/nommu.c~nommu-struct-vm_regions-vm_usage-count-need-not-be-atomic +++ a/mm/nommu.c @@ -552,11 +552,11 @@ static void free_page_series(unsigned lo static void __put_nommu_region(struct vm_region *region) __releases(nommu_region_sem) { - kenter("%p{%d}", region, atomic_read(®ion->vm_usage)); + kenter("%p{%d}", region, region->vm_usage); BUG_ON(!nommu_region_tree.rb_node); - if (atomic_dec_and_test(®ion->vm_usage)) { + if (--region->vm_usage == 0) { if (region->vm_top > region->vm_start) delete_nommu_region(region); up_write(&nommu_region_sem); @@ -1205,7 +1205,7 @@ unsigned long do_mmap_pgoff(struct file if (!vma) goto error_getting_vma; - atomic_set(®ion->vm_usage, 1); + region->vm_usage = 1; region->vm_flags = vm_flags; region->vm_pgoff = pgoff; @@ -1272,7 +1272,7 @@ unsigned long do_mmap_pgoff(struct file } /* we've found a region we can share */ - atomic_inc(&pregion->vm_usage); + pregion->vm_usage++; vma->vm_region = pregion; start = pregion->vm_start; start += (pgoff - pregion->vm_pgoff) << PAGE_SHIFT; @@ -1289,7 +1289,7 @@ unsigned long do_mmap_pgoff(struct file vma->vm_region = NULL; vma->vm_start = 0; vma->vm_end = 0; - atomic_dec(&pregion->vm_usage); + pregion->vm_usage--; pregion = NULL; goto error_just_free; } @@ -1444,7 +1444,7 @@ int split_vma(struct mm_struct *mm, stru /* we're only permitted to split anonymous regions that have a single * owner */ if (vma->vm_file || - atomic_read(&vma->vm_region->vm_usage) != 1) + vma->vm_region->vm_usage != 1) return -ENOMEM; if (mm->map_count >= sysctl_max_map_count) @@ -1518,7 +1518,7 @@ static int shrink_vma(struct mm_struct * /* cut the backing region down to size */ region = vma->vm_region; - BUG_ON(atomic_read(®ion->vm_usage) != 1); + BUG_ON(region->vm_usage != 1); down_write(&nommu_region_sem); delete_nommu_region(region); _ Patches currently in -mm which might be from dhowells@xxxxxxxxxx are origin.patch linux-next.patch kernel-credc-use-kmem_cache_free.patch frv-duplicate-output_buffer-of-e03.patch coredump-unify-dump_seek-implementations-for-each-binfmt_c.patch coredump-move-dump_write-and-dump_seek-into-a-header-file.patch elf-coredump-replace-elf_core_extra_-macros-by-functions.patch elf-coredump-make-offset-calculation-process-and-writing-process-explicit.patch elf-coredump-add-extended-numbering-support.patch mutex-subsystem-synchro-test-module.patch mutex-subsystem-synchro-test-module-add-missing-header-file.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html