From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:32911) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eyIf0-0002it-03 for qemu-devel@nongnu.org; Tue, 20 Mar 2018 10:54:47 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eyIex-0001Cl-C7 for qemu-devel@nongnu.org; Tue, 20 Mar 2018 10:54:46 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:49804 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 1eyIex-0001CM-5W for qemu-devel@nongnu.org; Tue, 20 Mar 2018 10:54:43 -0400 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 A96FA80AD211 for ; Tue, 20 Mar 2018 14:54:42 +0000 (UTC) Date: Tue, 20 Mar 2018 16:54:35 +0200 From: "Michael S. Tsirkin" Message-ID: <20180320164842-mutt-send-email-mst@kernel.org> References: <20180312172124.56461-1-dgilbert@redhat.com> <20180312172124.56461-18-dgilbert@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline In-Reply-To: <20180312172124.56461-18-dgilbert@redhat.com> Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH v5 17/29] vhost+postcopy: Helper to send requests to source for shared pages 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, peterx@redhat.com, quintela@redhat.com, aarcange@redhat.com On Mon, Mar 12, 2018 at 05:21:12PM +0000, Dr. David Alan Gilbert (git) wr= ote: > From: "Dr. David Alan Gilbert" >=20 > Provide a helper to be used by shared waker functions to request > shared pages from the source. > The last_rb pointer is moved into the incoming state since this > helper can update it as well as the main fault thread function. >=20 > Signed-off-by: Dr. David Alan Gilbert > Reviewed-by: Marc-Andr=E9 Lureau > --- > migration/migration.h | 2 ++ > migration/postcopy-ram.c | 32 +++++++++++++++++++++++++++++--- > migration/postcopy-ram.h | 3 +++ > migration/trace-events | 2 ++ > 4 files changed, 36 insertions(+), 3 deletions(-) >=20 > diff --git a/migration/migration.h b/migration/migration.h > index d02a759331..83dc36b57a 100644 > --- a/migration/migration.h > +++ b/migration/migration.h > @@ -49,6 +49,8 @@ struct MigrationIncomingState { > int userfault_event_fd; > QEMUFile *to_src_file; > QemuMutex rp_mutex; /* We send replies from multiple threads */ > + /* RAMBlock of last request sent to source */ > + RAMBlock *last_rb; > void *postcopy_tmp_page; > void *postcopy_tmp_zero_page; > /* PostCopyFD's for external userfaultfds & handlers of shared mem= ory */ > diff --git a/migration/postcopy-ram.c b/migration/postcopy-ram.c > index 4ab1b7d36d..83780576ca 100644 > --- a/migration/postcopy-ram.c > +++ b/migration/postcopy-ram.c > @@ -525,6 +525,32 @@ static int ram_block_enable_notify(const char *blo= ck_name, void *host_addr, > return 0; > } > =20 > +/* > + * Callback from shared fault handlers to ask for a page, > + * the page must be specified by a RAMBlock and an offset in that rb > + * Note: Only for use by shared fault handlers (in fault thread) > + */ > +int postcopy_request_shared_page(struct PostCopyFD *pcfd, RAMBlock *rb= , > + uint64_t client_addr, uint64_t rb_off= set) > +{ > + size_t pagesize =3D qemu_ram_pagesize(rb); > + uint64_t aligned_rbo =3D rb_offset & ~(pagesize - 1); > + MigrationIncomingState *mis =3D migration_incoming_get_current(); > + > + trace_postcopy_request_shared_page(pcfd->idstr, qemu_ram_get_idstr= (rb), > + rb_offset); > + /* TODO: Check bitmap to see if we already have the page */ > + if (rb !=3D mis->last_rb) { > + mis->last_rb =3D rb; > + migrate_send_rp_req_pages(mis, qemu_ram_get_idstr(rb), > + aligned_rbo, pagesize); > + } else { > + /* Save some space */ > + migrate_send_rp_req_pages(mis, NULL, aligned_rbo, pagesize); > + } > + return 0; > +} > + > /* > * Handle faults detected by the USERFAULT markings > */ > @@ -535,9 +561,9 @@ static void *postcopy_ram_fault_thread(void *opaque= ) > int ret; > size_t index; > RAMBlock *rb =3D NULL; > - RAMBlock *last_rb =3D NULL; /* last RAMBlock we sent part of */ > =20 > trace_postcopy_ram_fault_thread_entry(); > + mis->last_rb =3D NULL; /* last RAMBlock we sent part of */ > qemu_sem_post(&mis->fault_thread_sem); > =20 > struct pollfd *pfd; > @@ -636,8 +662,8 @@ static void *postcopy_ram_fault_thread(void *opaque= ) > * Send the request to the source - we want to request one > * of our host page sizes (which is >=3D TPS) > */ > - if (rb !=3D last_rb) { > - last_rb =3D rb; > + if (rb !=3D mis->last_rb) { > + mis->last_rb =3D rb; > migrate_send_rp_req_pages(mis, qemu_ram_get_idstr(rb), > rb_offset, qemu_ram_pagesize(= rb)); > } else { > diff --git a/migration/postcopy-ram.h b/migration/postcopy-ram.h > index c8ced3470b..d7afab07d7 100644 > --- a/migration/postcopy-ram.h > +++ b/migration/postcopy-ram.h > @@ -164,5 +164,8 @@ struct PostCopyFD { > */ > void postcopy_register_shared_ufd(struct PostCopyFD *pcfd); > void postcopy_unregister_shared_ufd(struct PostCopyFD *pcfd); > +/* 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= ); > =20 > #endif > diff --git a/migration/trace-events b/migration/trace-events > index 1e617ad7a6..7c910b5479 100644 > --- a/migration/trace-events > +++ b/migration/trace-events > @@ -198,6 +198,8 @@ postcopy_ram_incoming_cleanup_closeuf(void) "" > 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, uint6= 4_t rb_offset) "for %s in %s offset 0x%"PRIx64 > + > save_xbzrle_page_skipping(void) "" > save_xbzrle_page_overflow(void) "" > ram_save_iterate_big_wait(uint64_t milliconds, int iterations) "big wa= it: %" PRIu64 " milliseconds, %d iterations" So this function was missing a stub. For the record, since 1842bdfdbac2ec46f2934d8914c874db83dd1344 we have a copy of linux system headers so ifdef for NR_userfaultfd is unnecessary on linux. Let's just drop it? > --=20 > 2.14.3