From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:54635) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cvkvz-0004hf-8U for qemu-devel@nongnu.org; Wed, 05 Apr 2017 09:25:16 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cvkvy-0000LU-FY for qemu-devel@nongnu.org; Wed, 05 Apr 2017 09:25:15 -0400 Received: from mail-wr0-x232.google.com ([2a00:1450:400c:c0c::232]:33752) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1cvkvy-0000L8-99 for qemu-devel@nongnu.org; Wed, 05 Apr 2017 09:25:14 -0400 Received: by mail-wr0-x232.google.com with SMTP id w43so14050803wrb.0 for ; Wed, 05 Apr 2017 06:25:14 -0700 (PDT) From: =?UTF-8?q?Alex=20Benn=C3=A9e?= Date: Wed, 5 Apr 2017 14:25:02 +0100 Message-Id: <20170405132503.32125-12-alex.bennee@linaro.org> In-Reply-To: <20170405132503.32125-1-alex.bennee@linaro.org> References: <20170405132503.32125-1-alex.bennee@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Subject: [Qemu-devel] [PATCH v2 11/12] cpus: call cpu_update_icount on read List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: dovgaluk@ispras.ru, rth@twiddle.net, pbonzini@redhat.com Cc: peter.maydell@linaro.org, qemu-devel@nongnu.org, mttcg@listserver.greensocs.com, fred.konrad@greensocs.com, a.rigo@virtualopensystems.com, cota@braap.org, bobby.prani@gmail.com, nikunj@linux.vnet.ibm.com, =?UTF-8?q?Alex=20Benn=C3=A9e?= , Peter Crosthwaite This ensures each time the vCPU thread reads the icount we update the master timer_state.qemu_icount field. This way as long as updates are in BQL protected sections (which they should be) the main-loop can never come to update the log and find time has gone backwards. Signed-off-by: Alex Bennée --- cpus.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/cpus.c b/cpus.c index ff75af449a..63de033cc8 100644 --- a/cpus.c +++ b/cpus.c @@ -246,19 +246,17 @@ void cpu_update_icount(CPUState *cpu) int64_t cpu_get_icount_raw(void) { - int64_t icount; CPUState *cpu = current_cpu; - icount = atomic_read(&timers_state.qemu_icount); if (cpu && cpu->running) { if (!cpu->can_do_io) { fprintf(stderr, "Bad icount read\n"); exit(1); } /* Take into account what has run */ - icount += cpu_get_icount_executed(cpu); + cpu_update_icount(cpu); } - return icount; + return atomic_read(&timers_state.qemu_icount); } /* Return the virtual CPU time, based on the instruction counter. */ -- 2.11.0