From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:56696) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1erfMt-0006xs-C9 for qemu-devel@nongnu.org; Fri, 02 Mar 2018 02:44:40 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1erfMq-0002FX-8e for qemu-devel@nongnu.org; Fri, 02 Mar 2018 02:44:39 -0500 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:59266 helo=mx1.redhat.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1erfMq-0002Dr-3J for qemu-devel@nongnu.org; Fri, 02 Mar 2018 02:44:36 -0500 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id DD1B240FB65B for ; Fri, 2 Mar 2018 07:44:24 +0000 (UTC) Date: Fri, 2 Mar 2018 15:44:08 +0800 From: Peter Xu Message-ID: <20180302074408.GL27381@xz-mi> References: <20180216131625.9639-1-dgilbert@redhat.com> <20180216131625.9639-20-dgilbert@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20180216131625.9639-20-dgilbert@redhat.com> Subject: Re: [Qemu-devel] [PATCH v3 19/29] postcopy: wake shared List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Dr. David Alan Gilbert (git)" Cc: qemu-devel@nongnu.org, maxime.coquelin@redhat.com, marcandre.lureau@redhat.com, imammedo@redhat.com, mst@redhat.com, quintela@redhat.com, aarcange@redhat.com On Fri, Feb 16, 2018 at 01:16:15PM +0000, Dr. David Alan Gilbert (git) wrote: > From: "Dr. David Alan Gilbert" > > Send a 'wake' request on a userfaultfd for a shared process. > The address in the clients address space is specified together > with the RAMBlock it was resolved to. I think it's "providing a helper to send WAKE to uffd" rather than really sending it. Otherwise it looks good to me. Thanks, > > Signed-off-by: Dr. David Alan Gilbert > --- > migration/postcopy-ram.c | 26 ++++++++++++++++++++++++++ > migration/postcopy-ram.h | 6 ++++++ > migration/trace-events | 1 + > 3 files changed, 33 insertions(+) > > diff --git a/migration/postcopy-ram.c b/migration/postcopy-ram.c > index 277ff749a0..67deae7e1c 100644 > --- a/migration/postcopy-ram.c > +++ b/migration/postcopy-ram.c > @@ -534,6 +534,25 @@ static int ram_block_enable_notify(const char *block_name, void *host_addr, > return 0; > } > > +int postcopy_wake_shared(struct PostCopyFD *pcfd, > + uint64_t client_addr, > + RAMBlock *rb) > +{ > + size_t pagesize = qemu_ram_pagesize(rb); > + struct uffdio_range range; > + int ret; > + trace_postcopy_wake_shared(client_addr, qemu_ram_get_idstr(rb)); > + range.start = client_addr & ~(pagesize - 1); > + range.len = pagesize; > + ret = ioctl(pcfd->fd, UFFDIO_WAKE, &range); > + if (ret) { > + error_report("%s: Failed to wake: %zx in %s (%s)", > + __func__, (size_t)client_addr, qemu_ram_get_idstr(rb), > + strerror(errno)); > + } > + return ret; > +} > + > /* > * Callback from shared fault handlers to ask for a page, > * the page must be specified by a RAMBlock and an offset in that rb > @@ -951,6 +970,13 @@ void *postcopy_get_tmp_page(MigrationIncomingState *mis) > return NULL; > } > > +int postcopy_wake_shared(struct PostCopyFD *pcfd, > + uint64_t client_addr, > + RAMBlock *rb) > +{ > + assert(0); > + return -1; > +} > #endif > > /* ------------------------------------------------------------------------- */ > diff --git a/migration/postcopy-ram.h b/migration/postcopy-ram.h > index 4c63f20df4..2e3dd844d5 100644 > --- a/migration/postcopy-ram.h > +++ b/migration/postcopy-ram.h > @@ -162,6 +162,12 @@ struct PostCopyFD { > */ > void postcopy_register_shared_ufd(struct PostCopyFD *pcfd); > void postcopy_unregister_shared_ufd(struct PostCopyFD *pcfd); > +/* Notify a client ufd that a page is available > + * Note: The 'client_address' is in the address space of the client > + * program not QEMU > + */ > +int postcopy_wake_shared(struct PostCopyFD *pcfd, uint64_t client_addr, > + RAMBlock *rb); > /* Callback from shared fault handlers to ask for a page */ > int postcopy_request_shared_page(struct PostCopyFD *pcfd, RAMBlock *rb, > uint64_t client_addr, uint64_t offset); > diff --git a/migration/trace-events b/migration/trace-events > index 7c910b5479..b0acaaa8a0 100644 > --- a/migration/trace-events > +++ b/migration/trace-events > @@ -199,6 +199,7 @@ postcopy_ram_incoming_cleanup_entry(void) "" > postcopy_ram_incoming_cleanup_exit(void) "" > postcopy_ram_incoming_cleanup_join(void) "" > postcopy_request_shared_page(const char *sharer, const char *rb, uint64_t rb_offset) "for %s in %s offset 0x%"PRIx64 > +postcopy_wake_shared(uint64_t client_addr, const char *rb) "at 0x%"PRIx64" in %s" > > save_xbzrle_page_skipping(void) "" > save_xbzrle_page_overflow(void) "" > -- > 2.14.3 > -- Peter Xu