From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:37657) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1b4rUu-0002Ht-Oe for qemu-devel@nongnu.org; Mon, 23 May 2016 11:10:25 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1b4rUj-00044a-BC for qemu-devel@nongnu.org; Mon, 23 May 2016 11:10:23 -0400 Received: from mail-wm0-x241.google.com ([2a00:1450:400c:c09::241]:33547) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1b4rUj-00044N-4c for qemu-devel@nongnu.org; Mon, 23 May 2016 11:10:13 -0400 Received: by mail-wm0-x241.google.com with SMTP id 67so16035809wmg.0 for ; Mon, 23 May 2016 08:10:13 -0700 (PDT) Sender: Paolo Bonzini From: Paolo Bonzini Date: Mon, 23 May 2016 17:09:45 +0200 Message-Id: <1464016199-43768-11-git-send-email-pbonzini@redhat.com> In-Reply-To: <1464016199-43768-1-git-send-email-pbonzini@redhat.com> References: <1464016199-43768-1-git-send-email-pbonzini@redhat.com> Subject: [Qemu-devel] [PULL 10/24] exec: adjust rcu_read_lock requirement List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Gonglei From: Gonglei qemu_ram_unset_idstr() doesn't need rcu lock anymore, meanwhile make the range of rcu lock in qemu_ram_set_idstr() as small as possible. Signed-off-by: Gonglei Message-Id: <1462845901-89716-3-git-send-email-arei.gonglei@huawei.com> Signed-off-by: Paolo Bonzini --- exec.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-) diff --git a/exec.c b/exec.c index e2966ce..8cf535d 100644 --- a/exec.c +++ b/exec.c @@ -1421,8 +1421,6 @@ void qemu_ram_set_idstr(RAMBlock *new_block, const char *name, DeviceState *dev) { RAMBlock *block; - rcu_read_lock(); - assert(new_block); assert(!new_block->idstr[0]); @@ -1435,6 +1433,7 @@ void qemu_ram_set_idstr(RAMBlock *new_block, const char *name, DeviceState *dev) } pstrcat(new_block->idstr, sizeof(new_block->idstr), name); + rcu_read_lock(); QLIST_FOREACH_RCU(block, &ram_list.blocks, next) { if (block != new_block && !strcmp(block->idstr, new_block->idstr)) { @@ -1453,12 +1452,9 @@ void qemu_ram_unset_idstr(RAMBlock *block) * migration. Ignore the problem since hot-unplug during migration * does not work anyway. */ - - rcu_read_lock(); if (block) { memset(block->idstr, 0, sizeof(block->idstr)); } - rcu_read_unlock(); } static int memory_try_enable_merging(void *addr, size_t len) -- 1.8.3.1