From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:54206) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1esvtR-0006Iu-9F for qemu-devel@nongnu.org; Mon, 05 Mar 2018 14:35:30 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1esvtN-0007PE-4h for qemu-devel@nongnu.org; Mon, 05 Mar 2018 14:35:29 -0500 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:41766 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 1esvtM-0007Ov-Pg for qemu-devel@nongnu.org; Mon, 05 Mar 2018 14:35:25 -0500 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 08804D142D for ; Mon, 5 Mar 2018 19:35:20 +0000 (UTC) Date: Mon, 5 Mar 2018 19:35:06 +0000 From: "Dr. David Alan Gilbert" Message-ID: <20180305193506.GV3131@work-vm> References: <20180216131625.9639-1-dgilbert@redhat.com> <20180216131625.9639-20-dgilbert@redhat.com> <20180302074408.GL27381@xz-mi> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180302074408.GL27381@xz-mi> Subject: Re: [Qemu-devel] [PATCH v3 19/29] postcopy: wake shared List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Peter Xu 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 * Peter Xu (peterx@redhat.com) wrote: > 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, Reworded to: postcopy: helper for waking shared Provide a helper to 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. Signed-off-by: Dr. David Alan Gilbert Dave > > > > 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 -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK