From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 5E51CC4829A for ; Wed, 14 Feb 2024 02:17:20 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ra4p2-0002ey-Es; Tue, 13 Feb 2024 21:16:28 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ra4p1-0002ep-2n for qemu-devel@nongnu.org; Tue, 13 Feb 2024 21:16:27 -0500 Received: from mail-lj1-x22b.google.com ([2a00:1450:4864:20::22b]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1ra4ou-0004Qz-Vt for qemu-devel@nongnu.org; Tue, 13 Feb 2024 21:16:26 -0500 Received: by mail-lj1-x22b.google.com with SMTP id 38308e7fff4ca-2d0e521de4eso46063441fa.2 for ; Tue, 13 Feb 2024 18:16:16 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance.com; s=google; t=1707876974; x=1708481774; darn=nongnu.org; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=5V6FpyFPQ7E0ae5GNa4iGILabDfaZQIL9Hpwr2R0pDY=; b=kMfJJt3sCrTXLfNAQ751vIAYC4DZ5fFpFySuCX2fXh/C/7SqopGgY3sROA7VM1QcX3 8W4Y2QVuyOw/VRTc2ZlwnkYkQ2OKuPRn94mC9H5CBnxpms1hIwFoHJgf7gqer9hEW3xN G3MCvHGTvJ8eP5Bz94/jROdzRWIvrBUHi4/31oeaz2uhn1d6cx6a3RgF6NDRmvocp8fS W+AIYIR4Bvi7EGBsFcM0GVwoUI/PciYXeG5OCt+XdIiXuTDoyTggAReAeawtbNR1d48f fcUtETBtpzEnZQ9yKp5ml1ghF+xNcuQGRqTHRIicjiO8TYuXiUvEfFdw+kCcj8/bcs/o i4rA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1707876974; x=1708481774; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=5V6FpyFPQ7E0ae5GNa4iGILabDfaZQIL9Hpwr2R0pDY=; b=NYDPz05FwuT8+ZchnkqKYkN9QjnJLaJAmuUOKGu4WEwWFkicGH4gI7yBsO6ajnSjAn r7JkdBq98bvu+7d2oN2ZQl6vjQe3jL/2wc2t1rKF6WOduGpX3LUCx+LGS2958REslCGc swkHrH9lSwQunv2BKS682Nz+UFhtco0aiCw5amIYoVCeojFPYjj67kAvV5Xbcp410v1G LFSLIWTp7AFFINIBgu9Mf9Dq14bb11K+c1zd62iS2u103rn2cEqS4NH/oYpQsKPFUPcA rlZo+Q7tto9XOOYboBkksvWAfPHJsATiiawtgEbyTqtxUQsoL4Rfd1s5g7baiQQR69cw BZMg== X-Forwarded-Encrypted: i=1; AJvYcCV1NlwpNb0bEziGIrGNWIXZQiZYitwZ+aONUe8hMCDxVxa3dWGK2XmIVBVySgTv3sStVXs1NjxJW/JxmSpesH6ZGzlN9dI= X-Gm-Message-State: AOJu0YxmszO1ZiwKqnL7jDGhZJotjrpNyFyUDhDTKEB3ciJlmXv/Wwon SXzG45JUN3203JChkNQzhsOvyR3fcLzZoNJ/h1yGIwClY/imC4/vg5wO6OBZQoz5d6dcKZS7XJ5 iO2pt3q0k/OwGckpc5sW7DzVsRV9jt8zzaA5q7Q== X-Google-Smtp-Source: AGHT+IEcJ2d20O7DyZyxCpsTCnxRtu2+gwJZug1hsrPYEyAWvgEH445hnKHrp3KkP8ElN/GPghsoOBBHg17Hk89abHs= X-Received: by 2002:a05:651c:2106:b0:2d1:1911:e704 with SMTP id a6-20020a05651c210600b002d11911e704mr331529ljq.38.1707876974445; Tue, 13 Feb 2024 18:16:14 -0800 (PST) MIME-Version: 1.0 References: <20240202102857.110210-1-peterx@redhat.com> <20240202102857.110210-6-peterx@redhat.com> <871q9lde2o.fsf@suse.de> In-Reply-To: <871q9lde2o.fsf@suse.de> From: Hao Xiang Date: Tue, 13 Feb 2024 18:16:03 -0800 Message-ID: Subject: Re: [External] [PATCH v2 05/23] migration/multifd: Drop MultiFDSendParams.normal[] array To: Fabiano Rosas Cc: peterx@redhat.com, qemu-devel@nongnu.org, Bryan Zhang , Avihai Horon , Yuan Liu , Prasad Pandit Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Received-SPF: pass client-ip=2a00:1450:4864:20::22b; envelope-from=hao.xiang@bytedance.com; helo=mail-lj1-x22b.google.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01, T_SPF_HELO_TEMPERROR=0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Fri, Feb 9, 2024 at 4:20=E2=80=AFAM Fabiano Rosas wrot= e: > > Hao Xiang writes: > > > On Fri, Feb 2, 2024 at 2:30=E2=80=AFAM wrote: > >> > >> From: Peter Xu > >> > >> This array is redundant when p->pages exists. Now we extended the lif= e of > >> p->pages to the whole period where pending_job is set, it should be sa= fe to > >> always use p->pages->offset[] rather than p->normal[]. Drop the array= . > >> > >> Alongside, the normal_num is also redundant, which is the same to > >> p->pages->num. > > > > Can we not drop p->normal and p_normal_num? It is redundant now but I > > think it will be needed for multifd zero page checking. In multifd > > zero page, we find out all zero pages and we sort the normal pages and > > zero pages in two seperate arrays. p->offset is the original array of > > pages, p->normal will contain the array of normal pages and p->zero > > will contain the array of zero pages. > > We're moving send_fill_packet into send_prepare(), so you should be able > to do whatever data transformation at send_prepare() and add any fields > you need into p->pages. > > If we keep p->normal we will not be able to switch into an opaque > payload later on. There should be no mention of pages outside of > hooks. This is long-term work, but let's avoid blocking it if possible. > Got it. I will make the proper changes. Aside from that, I would like to get opinions from you guys regarding zero page detection interface. Here are the options I am thinking: 1) Do zero page detection in send_prepare(). This means no dedicated hook for zero_page_detection() otherwise we will be calling a hook from inside a hook. But we will need a new function multifd_zero_page_check_send() similar to how we use multifd_send_fill_packet() now. multifd_zero_page_check_send() will need to be called by all send_prepare() implementations. 2) Do zero page detection in a new hook zero_page_detection(). zero_page_detection will be called before send_prepare(). Seems like extra complexity but I can go with that routine if you guys think it's a cleaner way. I am leaning towards 1) right now. > >> > >> This doesn't apply to recv side, because there's no extra buffering on= recv > >> side, so p->normal[] array is still needed. > >> > >> Reviewed-by: Fabiano Rosas > >> Signed-off-by: Peter Xu > >> --- > >> migration/multifd.h | 4 ---- > >> migration/multifd-zlib.c | 7 ++++--- > >> migration/multifd-zstd.c | 7 ++++--- > >> migration/multifd.c | 33 +++++++++++++-------------------- > >> 4 files changed, 21 insertions(+), 30 deletions(-) > >> > >> diff --git a/migration/multifd.h b/migration/multifd.h > >> index 7c040cb85a..3920bdbcf1 100644 > >> --- a/migration/multifd.h > >> +++ b/migration/multifd.h > >> @@ -122,10 +122,6 @@ typedef struct { > >> struct iovec *iov; > >> /* number of iovs used */ > >> uint32_t iovs_num; > >> - /* Pages that are not zero */ > >> - ram_addr_t *normal; > >> - /* num of non zero pages */ > >> - uint32_t normal_num; > >> /* used for compression methods */ > >> void *data; > >> } MultiFDSendParams; > >> diff --git a/migration/multifd-zlib.c b/migration/multifd-zlib.c > >> index 37ce48621e..100809abc1 100644 > >> --- a/migration/multifd-zlib.c > >> +++ b/migration/multifd-zlib.c > >> @@ -116,17 +116,18 @@ static void zlib_send_cleanup(MultiFDSendParams = *p, Error **errp) > >> */ > >> static int zlib_send_prepare(MultiFDSendParams *p, Error **errp) > >> { > >> + MultiFDPages_t *pages =3D p->pages; > >> struct zlib_data *z =3D p->data; > >> z_stream *zs =3D &z->zs; > >> uint32_t out_size =3D 0; > >> int ret; > >> uint32_t i; > >> > >> - for (i =3D 0; i < p->normal_num; i++) { > >> + for (i =3D 0; i < pages->num; i++) { > >> uint32_t available =3D z->zbuff_len - out_size; > >> int flush =3D Z_NO_FLUSH; > >> > >> - if (i =3D=3D p->normal_num - 1) { > >> + if (i =3D=3D pages->num - 1) { > >> flush =3D Z_SYNC_FLUSH; > >> } > >> > >> @@ -135,7 +136,7 @@ static int zlib_send_prepare(MultiFDSendParams *p,= Error **errp) > >> * with compression. zlib does not guarantee that this is saf= e, > >> * therefore copy the page before calling deflate(). > >> */ > >> - memcpy(z->buf, p->pages->block->host + p->normal[i], p->page_= size); > >> + memcpy(z->buf, p->pages->block->host + pages->offset[i], p->p= age_size); > >> zs->avail_in =3D p->page_size; > >> zs->next_in =3D z->buf; > >> > >> diff --git a/migration/multifd-zstd.c b/migration/multifd-zstd.c > >> index b471daadcd..2023edd8cc 100644 > >> --- a/migration/multifd-zstd.c > >> +++ b/migration/multifd-zstd.c > >> @@ -113,6 +113,7 @@ static void zstd_send_cleanup(MultiFDSendParams *p= , Error **errp) > >> */ > >> static int zstd_send_prepare(MultiFDSendParams *p, Error **errp) > >> { > >> + MultiFDPages_t *pages =3D p->pages; > >> struct zstd_data *z =3D p->data; > >> int ret; > >> uint32_t i; > >> @@ -121,13 +122,13 @@ static int zstd_send_prepare(MultiFDSendParams *= p, Error **errp) > >> z->out.size =3D z->zbuff_len; > >> z->out.pos =3D 0; > >> > >> - for (i =3D 0; i < p->normal_num; i++) { > >> + for (i =3D 0; i < pages->num; i++) { > >> ZSTD_EndDirective flush =3D ZSTD_e_continue; > >> > >> - if (i =3D=3D p->normal_num - 1) { > >> + if (i =3D=3D pages->num - 1) { > >> flush =3D ZSTD_e_flush; > >> } > >> - z->in.src =3D p->pages->block->host + p->normal[i]; > >> + z->in.src =3D p->pages->block->host + pages->offset[i]; > >> z->in.size =3D p->page_size; > >> z->in.pos =3D 0; > >> > >> diff --git a/migration/multifd.c b/migration/multifd.c > >> index 5633ac245a..8bb1fd95cf 100644 > >> --- a/migration/multifd.c > >> +++ b/migration/multifd.c > >> @@ -90,13 +90,13 @@ static int nocomp_send_prepare(MultiFDSendParams *= p, Error **errp) > >> { > >> MultiFDPages_t *pages =3D p->pages; > >> > >> - for (int i =3D 0; i < p->normal_num; i++) { > >> - p->iov[p->iovs_num].iov_base =3D pages->block->host + p->norm= al[i]; > >> + for (int i =3D 0; i < pages->num; i++) { > >> + p->iov[p->iovs_num].iov_base =3D pages->block->host + pages->= offset[i]; > >> p->iov[p->iovs_num].iov_len =3D p->page_size; > >> p->iovs_num++; > >> } > >> > >> - p->next_packet_size =3D p->normal_num * p->page_size; > >> + p->next_packet_size =3D pages->num * p->page_size; > >> p->flags |=3D MULTIFD_FLAG_NOCOMP; > >> return 0; > >> } > >> @@ -269,21 +269,22 @@ static void multifd_pages_clear(MultiFDPages_t *= pages) > >> static void multifd_send_fill_packet(MultiFDSendParams *p) > >> { > >> MultiFDPacket_t *packet =3D p->packet; > >> + MultiFDPages_t *pages =3D p->pages; > >> int i; > >> > >> packet->flags =3D cpu_to_be32(p->flags); > >> packet->pages_alloc =3D cpu_to_be32(p->pages->allocated); > >> - packet->normal_pages =3D cpu_to_be32(p->normal_num); > >> + packet->normal_pages =3D cpu_to_be32(pages->num); > >> packet->next_packet_size =3D cpu_to_be32(p->next_packet_size); > >> packet->packet_num =3D cpu_to_be64(p->packet_num); > >> > >> - if (p->pages->block) { > >> - strncpy(packet->ramblock, p->pages->block->idstr, 256); > >> + if (pages->block) { > >> + strncpy(packet->ramblock, pages->block->idstr, 256); > >> } > >> > >> - for (i =3D 0; i < p->normal_num; i++) { > >> + for (i =3D 0; i < pages->num; i++) { > >> /* there are architectures where ram_addr_t is 32 bit */ > >> - uint64_t temp =3D p->normal[i]; > >> + uint64_t temp =3D pages->offset[i]; > >> > >> packet->offset[i] =3D cpu_to_be64(temp); > >> } > >> @@ -570,8 +571,6 @@ void multifd_save_cleanup(void) > >> p->packet =3D NULL; > >> g_free(p->iov); > >> p->iov =3D NULL; > >> - g_free(p->normal); > >> - p->normal =3D NULL; > >> multifd_send_state->ops->send_cleanup(p, &local_err); > >> if (local_err) { > >> migrate_set_error(migrate_get_current(), local_err); > >> @@ -688,8 +687,8 @@ static void *multifd_send_thread(void *opaque) > >> > >> if (p->pending_job) { > >> uint64_t packet_num =3D p->packet_num; > >> + MultiFDPages_t *pages =3D p->pages; > >> uint32_t flags; > >> - p->normal_num =3D 0; > >> > >> if (use_zero_copy_send) { > >> p->iovs_num =3D 0; > >> @@ -697,12 +696,7 @@ static void *multifd_send_thread(void *opaque) > >> p->iovs_num =3D 1; > >> } > >> > >> - for (int i =3D 0; i < p->pages->num; i++) { > >> - p->normal[p->normal_num] =3D p->pages->offset[i]; > >> - p->normal_num++; > >> - } > >> - > >> - if (p->normal_num) { > >> + if (pages->num) { > >> ret =3D multifd_send_state->ops->send_prepare(p, &loc= al_err); > >> if (ret !=3D 0) { > >> qemu_mutex_unlock(&p->mutex); > >> @@ -713,10 +707,10 @@ static void *multifd_send_thread(void *opaque) > >> flags =3D p->flags; > >> p->flags =3D 0; > >> p->num_packets++; > >> - p->total_normal_pages +=3D p->normal_num; > >> + p->total_normal_pages +=3D pages->num; > >> qemu_mutex_unlock(&p->mutex); > >> > >> - trace_multifd_send(p->id, packet_num, p->normal_num, flag= s, > >> + trace_multifd_send(p->id, packet_num, pages->num, flags, > >> p->next_packet_size); > >> > >> if (use_zero_copy_send) { > >> @@ -924,7 +918,6 @@ int multifd_save_setup(Error **errp) > >> p->name =3D g_strdup_printf("multifdsend_%d", i); > >> /* We need one extra place for the packet header */ > >> p->iov =3D g_new0(struct iovec, page_count + 1); > >> - p->normal =3D g_new0(ram_addr_t, page_count); > >> p->page_size =3D qemu_target_page_size(); > >> p->page_count =3D page_count; > >> > >> -- > >> 2.43.0 > >>