From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:36818) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1axtBX-0004Oq-PX for qemu-devel@nongnu.org; Wed, 04 May 2016 05:33:42 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1axtBL-0003dC-TZ for qemu-devel@nongnu.org; Wed, 04 May 2016 05:33:30 -0400 Received: from mx1.redhat.com ([209.132.183.28]:34020) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1axtBL-0003au-Mf for qemu-devel@nongnu.org; Wed, 04 May 2016 05:33:23 -0400 From: Juan Quintela In-Reply-To: <1462333259-3237-6-git-send-email-liang.z.li@intel.com> (Liang Li's message of "Wed, 4 May 2016 11:40:59 +0800") References: <1462333259-3237-1-git-send-email-liang.z.li@intel.com> <1462333259-3237-6-git-send-email-liang.z.li@intel.com> Reply-To: quintela@redhat.com Date: Wed, 04 May 2016 11:33:09 +0200 Message-ID: <87r3ditbfu.fsf@emacs.mitica> MIME-Version: 1.0 Content-Type: text/plain Subject: Re: [Qemu-devel] [PATCH 5/5] migration: refine ram_save_compressed_page List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Liang Li Cc: qemu-devel@nongnu.org, amit.shah@redhat.com, berrange@redhat.com, dgilbert@redhat.com Liang Li wrote: > Use qemu_put_compression_data to do the compression directly > instead of using do_compress_ram_page, avoid some data copy. > very small improvement, at the same time, add code to check > if the compression is successful. > > Signed-off-by: Liang Li > --- > migration/ram.c | 28 +++++++++++++--------------- > 1 file changed, 13 insertions(+), 15 deletions(-) > > diff --git a/migration/ram.c b/migration/ram.c > index 7e62d8d..ec2c0bf 100644 > --- a/migration/ram.c > +++ b/migration/ram.c > @@ -927,24 +927,20 @@ static int ram_save_compressed_page(QEMUFile *f, PageSearchStatus *pss, > uint64_t *bytes_transferred) > { > int pages = -1; > - uint64_t bytes_xmit; > + uint64_t bytes_xmit = 0; > uint8_t *p; > - int ret; > + int ret, blen; > RAMBlock *block = pss->block; > ram_addr_t offset = pss->offset; > > p = block->host + offset; > > - bytes_xmit = 0; > ret = ram_control_save_page(f, block->offset, > offset, TARGET_PAGE_SIZE, &bytes_xmit); > if (bytes_xmit) { > *bytes_transferred += bytes_xmit; > pages = 1; > } > - if (block == last_sent_block) { > - offset |= RAM_SAVE_FLAG_CONTINUE; > - } > if (ret != RAM_SAVE_CONTROL_NOT_SUPP) { > if (ret != RAM_SAVE_CONTROL_DELAYED) { > if (bytes_xmit > 0) { > @@ -964,17 +960,19 @@ static int ram_save_compressed_page(QEMUFile *f, PageSearchStatus *pss, > flush_compressed_data(f); > pages = save_zero_page(f, block, offset, p, bytes_transferred); > if (pages == -1) { > - set_compress_params(&comp_param[0], block, offset); > - /* Use the qemu thread to compress the data to make sure the > - * first page is sent out before other pages > - */ > - bytes_xmit = do_compress_ram_page(&comp_param[0]); > - acct_info.norm_pages++; > - qemu_put_qemu_file(f, comp_param[0].file); > - *bytes_transferred += bytes_xmit; > - pages = 1; > + /* Make sure the first page is sent out before other pages */ > + bytes_xmit = save_page_header(f, block, offset | > + RAM_SAVE_FLAG_COMPRESS_PAGE); > + blen = qemu_put_compression_data(f, p, TARGET_PAGE_SIZE, > + migrate_compress_level()); > + if (blen > 0) { > + *bytes_transferred += bytes_xmit + blen; > + acct_info.norm_pages++; > + pages = 1; > + } > } > } else { > + offset |= RAM_SAVE_FLAG_CONTINUE; > pages = save_zero_page(f, block, offset, p, bytes_transferred); > if (pages == -1) { > pages = compress_page_with_multi_thread(f, block, offset, You need to decide what to do when blen <= 0. As said in previous patch, I can only think of aborting migration. But ignoring the error is not an option IMHO. Later, Juan.