From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:58112) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cw4aM-0002vu-Rf for qemu-devel@nongnu.org; Thu, 06 Apr 2017 06:24:15 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cw4aH-0004GN-Su for qemu-devel@nongnu.org; Thu, 06 Apr 2017 06:24:14 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:42676) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1cw4aH-0004G1-I0 for qemu-devel@nongnu.org; Thu, 06 Apr 2017 06:24:09 -0400 Received: from pps.filterd (m0098399.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.20/8.16.0.20) with SMTP id v36ANqsb138749 for ; Thu, 6 Apr 2017 06:24:08 -0400 Received: from e23smtp04.au.ibm.com (e23smtp04.au.ibm.com [202.81.31.146]) by mx0a-001b2d01.pphosted.com with ESMTP id 29n1byvg61-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Thu, 06 Apr 2017 06:24:08 -0400 Received: from localhost by e23smtp04.au.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Thu, 6 Apr 2017 20:24:05 +1000 From: Nikunj A Dadhania Date: Thu, 6 Apr 2017 15:52:48 +0530 In-Reply-To: <20170406102249.20383-1-nikunj@linux.vnet.ibm.com> References: <20170406102249.20383-1-nikunj@linux.vnet.ibm.com> Message-Id: <20170406102249.20383-3-nikunj@linux.vnet.ibm.com> Subject: [Qemu-devel] [PATCH RFC v1 2/3] cputlb: handle first atomic write to the page List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-ppc@nongnu.org, david@gibson.dropbear.id.au, rth@twiddle.net Cc: qemu-devel@nongnu.org, alex.bennee@linaro.org, programmingkidx@gmail.com, bharata@linux.vnet.ibm.com, nikunj@linux.vnet.ibm.com In case where the conditional write is the first write to the page, TLB_NOTDIRTY will be set and stop_the_world is triggered. Handle this as a special case and set the dirty bit. After that fall through to the actual atomic instruction below. Signed-off-by: Nikunj A Dadhania --- cputlb.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/cputlb.c b/cputlb.c index f5d056c..743776a 100644 --- a/cputlb.c +++ b/cputlb.c @@ -930,7 +930,13 @@ static void *atomic_mmu_lookup(CPUArchState *env, target_ulong addr, tlb_addr = tlbe->addr_write; } - /* Notice an IO access, or a notdirty page. */ + /* Check notdirty */ + if (unlikely(tlb_addr & TLB_NOTDIRTY)) { + tlb_set_dirty(ENV_GET_CPU(env), addr); + tlb_addr = tlb_addr & ~TLB_NOTDIRTY; + } + + /* Notice an IO access */ if (unlikely(tlb_addr & ~TARGET_PAGE_MASK)) { /* There's really nothing that can be done to support this apart from stop-the-world. */ -- 2.9.3