From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:45292) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dLmwt-0002S9-Ds for qemu-devel@nongnu.org; Fri, 16 Jun 2017 04:49:52 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dLmwp-00014W-Ei for qemu-devel@nongnu.org; Fri, 16 Jun 2017 04:49:47 -0400 Received: from mx1.redhat.com ([209.132.183.28]:54644) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dLmwp-00013d-56 for qemu-devel@nongnu.org; Fri, 16 Jun 2017 04:49:43 -0400 Date: Fri, 16 Jun 2017 16:49:36 +0800 From: Peter Xu Message-ID: <20170616084936.GG30118@pxdev.xzpeter.org> References: <1497544575-18628-1-git-send-email-a.perevalov@samsung.com> <1497544575-18628-3-git-send-email-a.perevalov@samsung.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <1497544575-18628-3-git-send-email-a.perevalov@samsung.com> Subject: Re: [Qemu-devel] [PATCH v2 2/3] migration: introduce qemu_ufd_copy_ioctl helper List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Alexey Perevalov Cc: qemu-devel@nongnu.org, i.maximets@samsung.com, quintela@redhat.com, dgilbert@redhat.com On Thu, Jun 15, 2017 at 07:36:14PM +0300, Alexey Perevalov wrote: > Just for placing auxilary operations inside helper, > auxilary operations like: track received pages, > notify about copying operation in futher patches. > > Signed-off-by: Alexey Perevalov > --- > migration/postcopy-ram.c | 35 ++++++++++++++++++++++------------- > 1 file changed, 22 insertions(+), 13 deletions(-) > > diff --git a/migration/postcopy-ram.c b/migration/postcopy-ram.c > index 743ca6c..38a429a 100644 > --- a/migration/postcopy-ram.c > +++ b/migration/postcopy-ram.c > @@ -561,6 +561,26 @@ int postcopy_ram_enable_notify(MigrationIncomingState *mis) > return 0; > } > > +static int qemu_ufd_copy_ioctl(int userfault_fd, void *host_addr, > + void *from_addr, uint64_t pagesize) > +{ > + if (from_addr) { > + struct uffdio_copy copy_struct; > + copy_struct.dst = (uint64_t)(uintptr_t)host_addr; > + copy_struct.src = (uint64_t)(uintptr_t)from_addr; > + copy_struct.len = pagesize; > + copy_struct.mode = 0; > + return ioctl(userfault_fd, UFFDIO_COPY, ©_struct); > + } else { > + struct uffdio_zeropage zero_struct; > + zero_struct.range.start = (uint64_t)(uintptr_t)host_addr; > + zero_struct.range.len = pagesize; > + zero_struct.mode = 0; > + return ioctl(userfault_fd, UFFDIO_ZEROPAGE, &zero_struct); > + } > + return 0; Remove this line? > +} > + > /* > * Place a host page (from) at (host) atomically > * returns 0 on success > @@ -568,20 +588,14 @@ int postcopy_ram_enable_notify(MigrationIncomingState *mis) > int postcopy_place_page(MigrationIncomingState *mis, void *host, void *from, > RAMBlock *rb) > { > - struct uffdio_copy copy_struct; > size_t pagesize = qemu_ram_pagesize(rb); > > - copy_struct.dst = (uint64_t)(uintptr_t)host; > - copy_struct.src = (uint64_t)(uintptr_t)from; > - copy_struct.len = pagesize; > - copy_struct.mode = 0; > - > /* copy also acks to the kernel waking the stalled thread up > * TODO: We can inhibit that ack and only do it if it was requested > * which would be slightly cheaper, but we'd have to be careful > * of the order of updating our page state. > */ > - if (ioctl(mis->userfault_fd, UFFDIO_COPY, ©_struct)) { > + if (qemu_ufd_copy_ioctl(mis->userfault_fd, host, from, pagesize)) { (hmm I know "from" won't be zero, but naturally if without the context I would doubt it. Shall we add an assert here? You call.) Besides: Reviewed-by: Peter Xu Thanks, > int e = errno; > error_report("%s: %s copy host: %p from: %p (size: %zd)", > __func__, strerror(e), host, from, pagesize); > @@ -605,12 +619,7 @@ int postcopy_place_page_zero(MigrationIncomingState *mis, void *host, > > pagesize = qemu_ram_pagesize(rb); > if (pagesize == getpagesize()) { > - struct uffdio_zeropage zero_struct; > - zero_struct.range.start = (uint64_t)(uintptr_t)host; > - zero_struct.range.len = getpagesize(); > - zero_struct.mode = 0; > - > - if (ioctl(mis->userfault_fd, UFFDIO_ZEROPAGE, &zero_struct)) { > + if (qemu_ufd_copy_ioctl(mis->userfault_fd, host, 0, getpagesize())) { > int e = errno; > error_report("%s: %s zero host: %p", > __func__, strerror(e), host); > -- > 1.9.1 > -- Peter Xu