From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:33050) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aBQB1-0004x4-R4 for qemu-devel@nongnu.org; Tue, 22 Dec 2015 11:52:44 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1aBQB0-0000XU-VI for qemu-devel@nongnu.org; Tue, 22 Dec 2015 11:52:43 -0500 Received: from mx1.redhat.com ([209.132.183.28]:40505) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aBQB0-0000XN-Qd for qemu-devel@nongnu.org; Tue, 22 Dec 2015 11:52:42 -0500 Date: Tue, 22 Dec 2015 18:52:39 +0200 From: "Michael S. Tsirkin" Message-ID: <1450803119-4223-2-git-send-email-mst@redhat.com> References: <1450803119-4223-1-git-send-email-mst@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1450803119-4223-1-git-send-email-mst@redhat.com> Subject: [Qemu-devel] [PULL 01/55] mmap-alloc: tweak a comment on ppc64 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Peter Maydell , Greg Kurz , Paolo Bonzini The comment I put in mmap-alloc to document the ppc64 rules refers to the previous revision of the patch: we don't look at memory alignment anymore, we check the fs from which the fd is mapped, instead. It's also not clear what does "in this case" refer to, rearrange text to make it clearer. Signed-off-by: Michael S. Tsirkin --- util/mmap-alloc.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/util/mmap-alloc.c b/util/mmap-alloc.c index 54793a5..5cd7f71 100644 --- a/util/mmap-alloc.c +++ b/util/mmap-alloc.c @@ -50,10 +50,11 @@ void *qemu_ram_mmap(int fd, size_t size, size_t align, bool shared) #if defined(__powerpc64__) && defined(__linux__) /* On ppc64 mappings in the same segment (aka slice) must share the same * page size. Since we will be re-allocating part of this segment - * from the supplied fd, we should make sure to use the same page size, - * unless we are using the system page size, in which case anonymous memory - * is OK. Use align as a hint for the page size. - * In this case, set MAP_NORESERVE to avoid allocating backing store memory. + * from the supplied fd, we should make sure to use the same page size, to + * this end we mmap the supplied fd. In this case, set MAP_NORESERVE to + * avoid allocating backing store memory. + * We do this unless we are using the system page size, in which case + * anonymous memory is OK. */ int anonfd = fd == -1 || qemu_fd_getpagesize(fd) == getpagesize() ? -1 : fd; int flags = anonfd == -1 ? MAP_ANONYMOUS : MAP_NORESERVE; -- MST