From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:38528) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WTZ20-0003qt-EG for qemu-devel@nongnu.org; Fri, 28 Mar 2014 11:49:26 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1WTZ1u-00006B-Bl for qemu-devel@nongnu.org; Fri, 28 Mar 2014 11:49:20 -0400 Received: from cantor2.suse.de ([195.135.220.15]:56634 helo=mx2.suse.de) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WTZ1u-000061-4z for qemu-devel@nongnu.org; Fri, 28 Mar 2014 11:49:14 -0400 From: =?UTF-8?q?Andreas=20F=C3=A4rber?= Date: Fri, 28 Mar 2014 16:49:04 +0100 Message-Id: <1396021744-29942-1-git-send-email-afaerber@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Subject: [Qemu-devel] [PATCH qom-cpu for-2.0] cpu: Avoid QOM casts for CPU() List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: laurent.desnogues@gmail.com, pbonzini@redhat.com, =?UTF-8?q?Andreas=20F=C3=A4rber?= CPU address spaces touching load and store helpers as well as the movement of (almost) all fields from CPU_COMMON to CPUState have led to a noticeable increase of CPU() usage in "hot" paths for both TCG and KVM. While CPU()'s OBJECT_CHECK() might help detect development errors, i.e. i= n form of crashes due to QOM vs. non-QOM mismatches rather than QOM type mismatches, it is not really needed at runtime since mostly used in CPU-specific paths, coming from a target-specific CPU subtype. If that pointer is damaged, other errors are highly likely occur elsewhere anyway= . Keep the CPU() macro for a consistent developer experience and flexibility to exchange its implementation, but turn it into a pure C cast for now. Reported-by: Laurent Desnogues Suggested-by: Paolo Bonzini Signed-off-by: Andreas F=C3=A4rber --- include/qom/cpu.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/include/qom/cpu.h b/include/qom/cpu.h index f99885a..0aa1bdc 100644 --- a/include/qom/cpu.h +++ b/include/qom/cpu.h @@ -53,7 +53,7 @@ typedef uint64_t vaddr; =20 #define TYPE_CPU "cpu" =20 -#define CPU(obj) OBJECT_CHECK(CPUState, (obj), TYPE_CPU) +#define CPU(obj) ((CPUState *)(obj)) #define CPU_CLASS(class) OBJECT_CLASS_CHECK(CPUClass, (class), TYPE_CPU) #define CPU_GET_CLASS(obj) OBJECT_GET_CLASS(CPUClass, (obj), TYPE_CPU) =20 --=20 1.8.4.5