Use __getpagesize and __ffs in MMAP2_PAGE_SHIFT == -1 case of mmap64.

diff --git a/ChangeLog b/ChangeLog
index 0880ef7..d6eb8dc 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,4 +1,10 @@
 2013-08-20  Joseph Myers  <joseph@codesourcery.com>
+
+       * sysdeps/unix/sysv/linux/mmap64.c (__mmap64)
+       [MMAP2_PAGE_SHIFT == -1]: Use __getpagesize to determine page
+       size.  Use __ffs to determine corresponding shift.
+
+2013-08-20  Joseph Myers  <joseph@codesourcery.com>
            Roland McGrath  <roland@hack.frob.com>
 
        * Makefile (INSTALL): Remove trailing blank lines from output of

diff --git a/sysdeps/unix/sysv/linux/mmap64.c b/sysdeps/unix/sysv/linux/mmap64.c
index e2dcdc4..4ba686c 100644 (file)
--- a/sysdeps/unix/sysv/linux/mmap64.c
+++ b/sysdeps/unix/sysv/linux/mmap64.c
@@ -42,9 +42,8 @@ __mmap64 (void *addr, size_t len, int prot, int flags, int fd, off64_t offset)
 #if MMAP2_PAGE_SHIFT == -1
   if (page_shift == 0)
     {
-      int page_size = getpagesize ();
-      while ((1 << ++page_shift) != page_size)
-       ;
+      int page_size = __getpagesize ();
+      page_shift = __ffs (page_size) - 1;
     }
 #endif
   if (offset & ((1 << page_shift) - 1))