From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:50451) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dIsxH-0006wA-Oa for qemu-devel@nongnu.org; Thu, 08 Jun 2017 04:38:13 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dIsxD-0000LP-Mj for qemu-devel@nongnu.org; Thu, 08 Jun 2017 04:38:11 -0400 Received: from mail-wr0-x22f.google.com ([2a00:1450:400c:c0c::22f]:34414) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1dIsxD-0000KZ-GE for qemu-devel@nongnu.org; Thu, 08 Jun 2017 04:38:07 -0400 Received: by mail-wr0-x22f.google.com with SMTP id g76so15315328wrd.1 for ; Thu, 08 Jun 2017 01:38:07 -0700 (PDT) References: <20170605165233.4135-1-rth@twiddle.net> <20170605165233.4135-23-rth@twiddle.net> <87h8zrdh02.fsf@linaro.org> <02d52209-3f94-7c06-3637-2ee84573d700@twiddle.net> From: Alex =?utf-8?Q?Benn=C3=A9e?= In-reply-to: <02d52209-3f94-7c06-3637-2ee84573d700@twiddle.net> Date: Thu, 08 Jun 2017 09:38:32 +0100 Message-ID: <877f0mdgc7.fsf@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Subject: Re: [Qemu-devel] [PULL 22/26] target/aarch64: optimize indirect branches List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Richard Henderson Cc: qemu-devel@nongnu.org, peter.maydell@linaro.org, "Emilio G. Cota" Richard Henderson writes: > On 06/07/2017 07:11 AM, Alex Bennée wrote: >> >> Richard Henderson writes: >> >>> From: "Emilio G. Cota" >>> >>> Measurements: >>> >>> [Baseline performance is that before applying this and the previous >>> commit] >> >> Sadly this has regressed my qemu-system-aarch64 EL2 run. It was slightly >> masked by an unrelated assertion breakage which I had to fix. However >> with this patch my boot hangs spinning all 4 threads. Once reverted >> things work again. >> >> My command line: >> >> timeout -k 1s --foreground 120s ./aarch64-softmmu/qemu-system-aarch64 -machine type=virt -display none -m 4096 -cpu cortex-a57 -serial mon:stdio -netdev user,id=unet -device virtio-net-device,netdev=unet -drive file=/home/alex/lsrc/qemu/images/jessie-arm64.qcow2,id=myblock,index=0,if=none -device virtio-blk-device,drive=myblock -append "console=ttyAMA0 root=/dev/vda1 systemd.unit=benchmark.service" -kernel /home/alex/lsrc/qemu/images/aarch64-current-linux-kernel-only.img -smp 4 -machine gic-version=3 -machine virtualization=true -name debug-threads=on > > If you ignore the timeout, does it complete eventually? It seems to hang indefinitely. The difference is between no output and the usual kernel output. > It may not be the same thing, but that pull left out the final patch > for target/alpha that enabled goto_ptr. But as I hadn't seen a > similar problem with other guests, I was assuming that the problem was > in hw/alpha/, or some other bit of the interrupt chain. Given output is being suppressed I wonder if there is some funkyness with IRQs going on here? > > > r~ -- Alex Bennée