From bee72b5893bfbffed54a1b3db46a99f4cb95f040 Mon Sep 17 00:00:00 2001 From: Keir Fraser Date: Fri, 23 Oct 2009 09:59:45 +0100 Subject: minios: Optimize mmap(open("/dev/mem")) Set map_frames_ex's stride parameter to 0 and increment to 1 to avoid building an explicit list of mfns. Signed-Off-By: Samuel Thibault --- extras/mini-os/lib/sys.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) (limited to 'extras/mini-os/lib') diff --git a/extras/mini-os/lib/sys.c b/extras/mini-os/lib/sys.c index 1284f5a714..6e12be0f4a 100644 --- a/extras/mini-os/lib/sys.c +++ b/extras/mini-os/lib/sys.c @@ -1256,11 +1256,8 @@ void *mmap(void *start, size_t length, int prot, int flags, int fd, off_t offset unsigned long zero = 0; return map_frames_ex(&zero, n, 0, 0, 1, DOMID_SELF, 0, 0); } else if (files[fd].type == FTYPE_MEM) { - int i; - unsigned long mfns[n]; - for (i = 0; i < n; i++) - mfns[i] = ((unsigned long) offset + (i * PAGE_SIZE)) >> PAGE_SHIFT; - return map_frames_ex(mfns, n, 1, 0, 1, DOMID_IO, 0, _PAGE_PRESENT|_PAGE_RW); + unsigned long first_mfn = offset >> PAGE_SHIFT; + return map_frames_ex(&first_mfn, n, 0, 1, 1, DOMID_IO, 0, _PAGE_PRESENT|_PAGE_RW); } else ASSERT(0); } -- cgit v1.2.3