From 0bb7ba6b9c358c12084a3cbc6ac08c8d1e973937 Mon Sep 17 00:00:00 2001 From: Fengguang Wu Date: Tue, 16 Oct 2007 01:24:32 -0700 Subject: [PATCH] readahead: mmap read-around simplification Fold file_ra_state.mmap_hit into file_ra_state.mmap_miss and make it an int. Signed-off-by: Fengguang Wu Cc: Rusty Russell Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/fs.h | 3 +-- mm/filemap.c | 4 ++-- 2 files changed, 3 insertions(+), 4 deletions(-) diff --git a/include/linux/fs.h b/include/linux/fs.h index 7a998c49a086..8250811081ff 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -703,8 +703,7 @@ struct file_ra_state { there are only # of pages ahead */ unsigned int ra_pages; /* Maximum readahead window */ - unsigned long mmap_hit; /* Cache hit stat for mmap accesses */ - unsigned long mmap_miss; /* Cache miss stat for mmap accesses */ + int mmap_miss; /* Cache miss stat for mmap accesses */ unsigned long prev_index; /* Cache last read() position */ unsigned int prev_offset; /* Offset where last read() ended in a page */ }; diff --git a/mm/filemap.c b/mm/filemap.c index 15c8413ee929..5dc18d76e703 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -1349,7 +1349,7 @@ int filemap_fault(struct vm_area_struct *vma, struct vm_fault *vmf) * Do we miss much more than hit in this file? If so, * stop bothering with read-ahead. It will only hurt. */ - if (ra->mmap_miss > ra->mmap_hit + MMAP_LOTSAMISS) + if (ra->mmap_miss > MMAP_LOTSAMISS) goto no_cached_page; /* @@ -1375,7 +1375,7 @@ int filemap_fault(struct vm_area_struct *vma, struct vm_fault *vmf) } if (!did_readaround) - ra->mmap_hit++; + ra->mmap_miss--; /* * We have a locked page in the page cache, now we need to check