From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:45546) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1d1XCO-0002pq-Ke for qemu-devel@nongnu.org; Fri, 21 Apr 2017 07:58:06 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1d1XCN-0007gY-IR for qemu-devel@nongnu.org; Fri, 21 Apr 2017 07:58:04 -0400 Received: from mx1.redhat.com ([209.132.183.28]:54710) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1d1XCN-0007fj-DB for qemu-devel@nongnu.org; Fri, 21 Apr 2017 07:58:03 -0400 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 4709D2EAAAA for ; Fri, 21 Apr 2017 11:58:02 +0000 (UTC) From: Juan Quintela Date: Fri, 21 Apr 2017 13:56:21 +0200 Message-Id: <20170421115646.15544-41-quintela@redhat.com> In-Reply-To: <20170421115646.15544-1-quintela@redhat.com> References: <20170421115646.15544-1-quintela@redhat.com> Subject: [Qemu-devel] [PULL 40/65] ram: Remove compression_switch and inline its logic List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: dgilbert@redhat.com We can calculate its value, so we don't create a variable for it. Signed-off-by: Juan Quintela Reviewed-by: Dr. David Alan Gilbert -- After Peter and Dave review, I dropped the variable and just inlined the condition. Fix typo --- migration/ram.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/migration/ram.c b/migration/ram.c index 14d54fd..fa5a290 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -336,7 +336,6 @@ static QemuCond comp_done_cond; /* The empty QEMUFileOps will be used by file in CompressParam */ static const QEMUFileOps empty_ops = { }; -static bool compression_switch; static DecompressParam *decomp_param; static QemuThread *decompress_threads; static QemuMutex decomp_done_lock; @@ -420,7 +419,6 @@ void migrate_compress_threads_create(void) if (!migrate_use_compression()) { return; } - compression_switch = true; thread_count = migrate_compress_threads(); compress_threads = g_new0(QemuThread, thread_count); comp_param = g_new0(CompressParam, thread_count); @@ -1092,7 +1090,6 @@ static bool find_dirty_block(RAMState *rs, PageSearchStatus *pss, * point. In theory, xbzrle can do better than compression. */ flush_compressed_data(rs); - compression_switch = false; } } /* Didn't find anything this time, but try again on the new block */ @@ -1326,7 +1323,14 @@ static int ram_save_target_page(RAMState *rs, MigrationState *ms, /* Check the pages is dirty and if it is send it */ if (migration_bitmap_clear_dirty(rs, dirty_ram_abs)) { unsigned long *unsentmap; - if (compression_switch && migrate_use_compression()) { + /* + * If xbzrle is on, stop using the data compression after first + * round of migration even if compression is enabled. In theory, + * xbzrle can do better than compression. + */ + + if (migrate_use_compression() + && (rs->ram_bulk_stage || !migrate_use_xbzrle())) { res = ram_save_compressed_page(rs, ms, pss, last_stage); } else { res = ram_save_page(rs, ms, pss, last_stage); -- 2.9.3