From: Juan Quintela <quintela@redhat.com> To: qemu-devel@nongnu.org Cc: Laurent Vivier <lvivier@redhat.com>, Richard Henderson <rth@twiddle.net>, Paolo Bonzini <pbonzini@redhat.com>, kvm@vger.kernel.org, "Dr. David Alan Gilbert" <dgilbert@redhat.com>, Juan Quintela <quintela@redhat.com>, Thomas Huth <thuth@redhat.com>, Wei Yang <richardw.yang@linux.intel.com> Subject: [PULL 05/19] migration/xbzrle: update cache and current_data in one place Date: Fri, 12 Jul 2019 16:31:53 +0200 Message-ID: <20190712143207.4214-6-quintela@redhat.com> (raw) In-Reply-To: <20190712143207.4214-1-quintela@redhat.com> From: Wei Yang <richardw.yang@linux.intel.com> When we are not in the last_stage, we need to update the cache if page is not the same. Currently this procedure is scattered in two places and mixed with encoding status check. This patch extract this general step out to make the code a little bit easy to read. Signed-off-by: Wei Yang <richardw.yang@linux.intel.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Message-Id: <20190610004159.20966-1-richardw.yang@linux.intel.com> Signed-off-by: Juan Quintela <quintela@redhat.com> --- migration/ram.c | 25 +++++++++++++++---------- 1 file changed, 15 insertions(+), 10 deletions(-) diff --git a/migration/ram.c b/migration/ram.c index 74c9306c78..d3d72b6f4f 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -1585,25 +1585,30 @@ static int save_xbzrle_page(RAMState *rs, uint8_t **current_data, encoded_len = xbzrle_encode_buffer(prev_cached_page, XBZRLE.current_buf, TARGET_PAGE_SIZE, XBZRLE.encoded_buf, TARGET_PAGE_SIZE); + + /* + * Update the cache contents, so that it corresponds to the data + * sent, in all cases except where we skip the page. + */ + if (!last_stage && encoded_len != 0) { + memcpy(prev_cached_page, XBZRLE.current_buf, TARGET_PAGE_SIZE); + /* + * In the case where we couldn't compress, ensure that the caller + * sends the data from the cache, since the guest might have + * changed the RAM since we copied it. + */ + *current_data = prev_cached_page; + } + if (encoded_len == 0) { trace_save_xbzrle_page_skipping(); return 0; } else if (encoded_len == -1) { trace_save_xbzrle_page_overflow(); xbzrle_counters.overflow++; - /* update data in the cache */ - if (!last_stage) { - memcpy(prev_cached_page, *current_data, TARGET_PAGE_SIZE); - *current_data = prev_cached_page; - } return -1; } - /* we need to update the data in the cache, in order to get the same data */ - if (!last_stage) { - memcpy(prev_cached_page, XBZRLE.current_buf, TARGET_PAGE_SIZE); - } - /* Send XBZRLE based compressed page */ bytes_xbzrle = save_page_header(rs, rs->f, block, offset | RAM_SAVE_FLAG_XBZRLE); -- 2.21.0
next prev parent reply index Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top 2019-07-12 14:31 [PULL 00/19] Migration patches Juan Quintela 2019-07-12 14:31 ` [PULL 01/19] migration: fix multifd_recv event typo Juan Quintela 2019-07-12 14:31 ` [PULL 02/19] migration-test: rename parameter to parameter_int Juan Quintela 2019-07-12 14:31 ` [PULL 03/19] migration-test: Add migration multifd test Juan Quintela 2019-07-12 14:31 ` [PULL 04/19] migration/multifd: call multifd_send_sync_main when sending RAM_SAVE_FLAG_EOS Juan Quintela 2019-07-12 14:31 ` Juan Quintela [this message] 2019-07-12 14:31 ` [PULL 06/19] cutils: remove one unnecessary pointer operation Juan Quintela 2019-07-12 14:31 ` [PULL 07/19] migration/multifd: sync packet_num after all thread are done Juan Quintela 2019-07-12 14:31 ` [PULL 08/19] migration/ram.c: reset complete_round when we gets a queued page Juan Quintela 2019-07-12 14:31 ` [PULL 09/19] migration: No need to take rcu during sync_dirty_bitmap Juan Quintela 2019-07-12 14:31 ` [PULL 10/19] memory: Don't set migration bitmap when without migration Juan Quintela 2019-07-12 14:31 ` [PULL 11/19] bitmap: Add bitmap_copy_with_{src|dst}_offset() Juan Quintela 2019-07-12 14:32 ` [PULL 12/19] memory: Pass mr into snapshot_and_clear_dirty Juan Quintela 2019-07-12 14:32 ` [PULL 13/19] memory: Introduce memory listener hook log_clear() Juan Quintela 2019-07-12 14:32 ` [PULL 14/19] kvm: Update comments for sync_dirty_bitmap Juan Quintela 2019-07-12 14:32 ` [PULL 15/19] kvm: Persistent per kvmslot dirty bitmap Juan Quintela 2019-07-12 14:32 ` [PULL 16/19] kvm: Introduce slots lock for memory listener Juan Quintela 2019-07-12 14:32 ` [PULL 17/19] kvm: Support KVM_CLEAR_DIRTY_LOG Juan Quintela 2019-07-12 14:32 ` [PULL 18/19] migration: Split log_clear() into smaller chunks Juan Quintela 2019-07-12 14:32 ` [PULL 19/19] migration: allow private destination ram with x-ignore-shared Juan Quintela 2019-07-12 16:33 ` [Qemu-devel] [PULL 00/19] Migration patches Peter Maydell 2019-07-12 17:54 ` Dr. David Alan Gilbert 2019-07-15 11:16 ` Peter Maydell 2019-07-15 13:44 ` Juan Quintela 2019-07-15 13:48 ` Peter Maydell 2019-07-15 14:10 ` Juan Quintela 2019-07-15 14:15 ` Peter Maydell 2019-07-15 14:04 ` [Qemu-devel] " Daniel P. Berrangé 2019-07-15 14:17 ` Peter Maydell -- strict thread matches above, loose matches on Subject: below -- 2019-07-11 10:43 Juan Quintela 2019-07-11 10:43 ` [PULL 05/19] migration/xbzrle: update cache and current_data in one place Juan Quintela
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