From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:51757) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1e54NN-0000mk-Gn for qemu-devel@nongnu.org; Thu, 19 Oct 2017 02:32:20 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1e54NM-0003FB-Ec for qemu-devel@nongnu.org; Thu, 19 Oct 2017 02:32:17 -0400 Received: from mx1.redhat.com ([209.132.183.28]:38392) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1e54NM-0003EJ-6W for qemu-devel@nongnu.org; Thu, 19 Oct 2017 02:32:16 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 48FAF820E6 for ; Thu, 19 Oct 2017 06:32:15 +0000 (UTC) From: Peter Xu Date: Thu, 19 Oct 2017 14:31:59 +0800 Message-Id: <20171019063200.19048-4-peterx@redhat.com> In-Reply-To: <20171019063200.19048-1-peterx@redhat.com> References: <20171019063200.19048-1-peterx@redhat.com> Subject: [Qemu-devel] [PATCH 3/4] migration: clean up xbzrle cache init/destroy List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Laurent Vivier , Juan Quintela , "Dr . David Alan Gilbert" , peterx@redhat.com Let's further simplify ram_init_all() and ram_save_cleanup() by abstract all the XBZRLE related codes into their own functions. When allocating xbzrle cache, we are always very careful on -ENOMEM; which makes sense. Replacing the last g_malloc0() with g_try_malloc0(), then refactor the logic a bit. This patch should be fixing some memory leaks when some memory allocation failed for XBZRLE in the past. Signed-off-by: Peter Xu --- migration/ram.c | 121 +++++++++++++++++++++++++++++++++++--------------------- 1 file changed, 76 insertions(+), 45 deletions(-) diff --git a/migration/ram.c b/migration/ram.c index 72c48e76e9..3df7715d63 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -1575,6 +1575,22 @@ static void ram_state_cleanup(RAMState **rsp) *rsp = NULL; } +static void xbzrle_cleanup(void) +{ + XBZRLE_cache_lock(); + if (XBZRLE.cache) { + cache_fini(XBZRLE.cache); + g_free(XBZRLE.encoded_buf); + g_free(XBZRLE.current_buf); + g_free(XBZRLE.zero_target_page); + XBZRLE.cache = NULL; + XBZRLE.encoded_buf = NULL; + XBZRLE.current_buf = NULL; + XBZRLE.zero_target_page = NULL; + } + XBZRLE_cache_unlock(); +} + static void ram_save_cleanup(void *opaque) { RAMState **rsp = opaque; @@ -1592,18 +1608,7 @@ static void ram_save_cleanup(void *opaque) block->unsentmap = NULL; } - XBZRLE_cache_lock(); - if (XBZRLE.cache) { - cache_fini(XBZRLE.cache); - g_free(XBZRLE.encoded_buf); - g_free(XBZRLE.current_buf); - g_free(XBZRLE.zero_target_page); - XBZRLE.cache = NULL; - XBZRLE.encoded_buf = NULL; - XBZRLE.current_buf = NULL; - XBZRLE.zero_target_page = NULL; - } - XBZRLE_cache_unlock(); + xbzrle_cleanup(); compress_threads_save_cleanup(); ram_state_cleanup(rsp); } @@ -2014,6 +2019,62 @@ err: return ret; } +/* + * For every allocation, we will try not to crash the VM if the + * allocation failed. + */ +static int xbzrle_init(void) +{ + if (!migrate_use_xbzrle()) { + return 0; + } + + XBZRLE_cache_lock(); + + XBZRLE.zero_target_page = g_try_malloc0(TARGET_PAGE_SIZE); + if (!XBZRLE.zero_target_page) { + error_report("%s: Error allocating zero page", __func__); + goto err_out; + } + + XBZRLE.cache = cache_init(migrate_xbzrle_cache_size() / + TARGET_PAGE_SIZE, + TARGET_PAGE_SIZE); + if (!XBZRLE.cache) { + error_report("%s: Error creating cache", __func__); + goto free_zero_page; + } + + XBZRLE.encoded_buf = g_try_malloc0(TARGET_PAGE_SIZE); + if (!XBZRLE.encoded_buf) { + error_report("%s: Error allocating encoded_buf", __func__); + goto free_cache; + } + + XBZRLE.current_buf = g_try_malloc(TARGET_PAGE_SIZE); + if (!XBZRLE.current_buf) { + error_report("%s: Error allocating current_buf", __func__); + goto free_encoded_buf; + } + + /* We are all good */ + XBZRLE_cache_unlock(); + return 0; + +free_encoded_buf: + g_free(XBZRLE.encoded_buf); + XBZRLE.encoded_buf = NULL; +free_cache: + cache_fini(XBZRLE.cache); + XBZRLE.cache = NULL; +free_zero_page: + g_free(XBZRLE.zero_target_page); + XBZRLE.zero_target_page = NULL; +err_out: + XBZRLE_cache_unlock(); + return -ENOMEM; +} + static int ram_state_init(RAMState **rsp) { *rsp = g_try_new0(RAMState, 1); @@ -2044,39 +2105,9 @@ static int ram_init_all(RAMState **rsp) return -1; } - if (migrate_use_xbzrle()) { - XBZRLE_cache_lock(); - XBZRLE.zero_target_page = g_malloc0(TARGET_PAGE_SIZE); - XBZRLE.cache = cache_init(migrate_xbzrle_cache_size() / - TARGET_PAGE_SIZE, - TARGET_PAGE_SIZE); - if (!XBZRLE.cache) { - XBZRLE_cache_unlock(); - error_report("Error creating cache"); - g_free(*rsp); - *rsp = NULL; - return -1; - } - XBZRLE_cache_unlock(); - - /* We prefer not to abort if there is no memory */ - XBZRLE.encoded_buf = g_try_malloc0(TARGET_PAGE_SIZE); - if (!XBZRLE.encoded_buf) { - error_report("Error allocating encoded_buf"); - g_free(*rsp); - *rsp = NULL; - return -1; - } - - XBZRLE.current_buf = g_try_malloc(TARGET_PAGE_SIZE); - if (!XBZRLE.current_buf) { - error_report("Error allocating current_buf"); - g_free(XBZRLE.encoded_buf); - XBZRLE.encoded_buf = NULL; - g_free(*rsp); - *rsp = NULL; - return -1; - } + if (xbzrle_init()) { + ram_state_cleanup(rsp); + return -1; } /* For memory_global_dirty_log_start below. */ -- 2.13.5