From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rusty Russell Subject: Re: [PATCHv5 2/3] virtio_console: Add support for remoteproc serial Date: Thu, 27 Sep 2012 09:22:24 +0930 Message-ID: <87haqk4a13.fsf@rustcorp.com.au> References: <1348580837-10919-1-git-send-email-sjur.brandeland@stericsson.com> <1348580837-10919-3-git-send-email-sjur.brandeland@stericsson.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: In-Reply-To: <1348580837-10919-3-git-send-email-sjur.brandeland@stericsson.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org To: Amit Shah Cc: Arnd Bergmann , "Michael S. Tsirkin" , sjurbren@stericsson.com, linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, Linus Walleij , Sjur =?utf-8?Q?Br=C3=A6ndeland?= List-Id: virtualization@lists.linuxfoundation.org c2p1ci5icmFuZGVsYW5kQHN0ZXJpY3Nzb24uY29tIHdyaXRlczoKPiBGcm9tOiBTanVyIEJyw6Zu ZGVsYW5kIDxzanVyLmJyYW5kZWxhbmRAc3Rlcmljc3Nvbi5jb20+Cj4KPiBBZGQgYSBzaW1wbGUg c2VyaWFsIGNvbm5lY3Rpb24gZHJpdmVyIGNhbGxlZAo+IFZJUlRJT19JRF9SUFJPQ19TRVJJQUwg KDExKSBmb3IgY29tbXVuaWNhdGluZyB3aXRoIGEKPiByZW1vdGUgcHJvY2Vzc29yIGluIGFuIGFz eW1tZXRyaWMgbXVsdGktcHJvY2Vzc2luZwo+IGNvbmZpZ3VyYXRpb24uCj4KLi4uCj4gIHN0YXRp YyBzdHJ1Y3QgcG9ydF9idWZmZXIgKmFsbG9jX2J1ZihzdHJ1Y3QgdmlydHF1ZXVlICp2cSwgc2l6 ZV90IGJ1Zl9zaXplLAo+ICAJCQkJICAgICBpbnQgbnJidWZzKQo+ICB7Cj4gIAlzdHJ1Y3QgcG9y dF9idWZmZXIgKmJ1ZjsKPiAgCXNpemVfdCBhbGxvY19zaXplOwo+ICAKPiArCWlmIChpc19ycHJv Y19zZXJpYWwodnEtPnZkZXYpICYmICFpcnFzX2Rpc2FibGVkKCkpCj4gKwkJcmVjbGFpbV9kbWFf YnVmcygpOwoKSG1tLCB5b3UgbmVlZCBhIGdmcF90IGFyZyBpbnRvIGFsbG9jX2J1ZjsgeW91ciBs YXN0IHBhdGNoIHNpbXBseSBjaGFuZ2VkCnRoZW0gYWxsIHRvIEdGUF9BVE9NSUMsIHdoaWNoIG1h a2VzIHRoZSBjb25zb2xlIGZhciBsZXNzIG1lbW9yeQpmcmllbmRseS4KCllvdSBjaGVjayAhaXJx c19kaXNhYmxlZCgpIGluIGEgY291cGxlIG9mIHBsYWNlczsgSSB0aGluayB0aGUgY2FsbGVyCm5l ZWRzIHRvIGluZGljYXRlIChwb3NzaWJseSBieSBjaGVja2luZyBmb3IgZ2ZwID09IEdGUF9LRVJO RUwpIHdoZXRoZXIKaXQncyBzYWZlIHRvIGNhbGwgcmVjbGFpbV9kbWFfYnVmcygpLgoKPiBAQCAt ODM4LDYgKzkyNywxMCBAQCBzdGF0aWMgc3NpemVfdCBwb3J0X2ZvcHNfc3BsaWNlX3dyaXRlKHN0 cnVjdCBwaXBlX2lub2RlX2luZm8gKnBpcGUsCj4gIAkJLnUuZGF0YSA9ICZzZ2wsCj4gIAl9Owo+ ICAKPiArCS8qIHJwcm9jX3NlcmlhbCBkb2VzIG5vdCBzdXBwb3J0IHNwbGljZSAqLwo+ICsJaWYg KGlzX3Jwcm9jX3NlcmlhbChwb3J0LT5vdXRfdnEtPnZkZXYpKQo+ICsJCXJldHVybiAtRUlOVkFM OwoKV2h5IG5vdD8gOykKClRoYW5rcywKUnVzdHkuCl9fX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX19fX19fX19fClZpcnR1YWxpemF0aW9uIG1haWxpbmcgbGlzdApWaXJ0dWFs aXphdGlvbkBsaXN0cy5saW51eC1mb3VuZGF0aW9uLm9yZwpodHRwczovL2xpc3RzLmxpbnV4Zm91 bmRhdGlvbi5vcmcvbWFpbG1hbi9saXN0aW5mby92aXJ0dWFsaXphdGlvbg== From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753936Ab2I0CFl (ORCPT ); Wed, 26 Sep 2012 22:05:41 -0400 Received: from ozlabs.org ([203.10.76.45]:53093 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753810Ab2I0CFj convert rfc822-to-8bit (ORCPT ); Wed, 26 Sep 2012 22:05:39 -0400 From: Rusty Russell To: sjur.brandeland@stericsson.com, Amit Shah Cc: linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, sjurbren@stericsson.com, Sjur =?utf-8?Q?Br=C3=A6ndeland?= , "Michael S. Tsirkin" , Ohad Ben-Cohen , Linus Walleij , Arnd Bergmann Subject: Re: [PATCHv5 2/3] virtio_console: Add support for remoteproc serial In-Reply-To: <1348580837-10919-3-git-send-email-sjur.brandeland@stericsson.com> References: <1348580837-10919-1-git-send-email-sjur.brandeland@stericsson.com> <1348580837-10919-3-git-send-email-sjur.brandeland@stericsson.com> User-Agent: Notmuch/0.13.2 (http://notmuchmail.org) Emacs/23.3.1 (i686-pc-linux-gnu) Date: Thu, 27 Sep 2012 09:22:24 +0930 Message-ID: <87haqk4a13.fsf@rustcorp.com.au> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org sjur.brandeland@stericsson.com writes: > From: Sjur Brændeland > > Add a simple serial connection driver called > VIRTIO_ID_RPROC_SERIAL (11) for communicating with a > remote processor in an asymmetric multi-processing > configuration. > ... > static struct port_buffer *alloc_buf(struct virtqueue *vq, size_t buf_size, > int nrbufs) > { > struct port_buffer *buf; > size_t alloc_size; > > + if (is_rproc_serial(vq->vdev) && !irqs_disabled()) > + reclaim_dma_bufs(); Hmm, you need a gfp_t arg into alloc_buf; your last patch simply changed them all to GFP_ATOMIC, which makes the console far less memory friendly. You check !irqs_disabled() in a couple of places; I think the caller needs to indicate (possibly by checking for gfp == GFP_KERNEL) whether it's safe to call reclaim_dma_bufs(). > @@ -838,6 +927,10 @@ static ssize_t port_fops_splice_write(struct pipe_inode_info *pipe, > .u.data = &sgl, > }; > > + /* rproc_serial does not support splice */ > + if (is_rproc_serial(port->out_vq->vdev)) > + return -EINVAL; Why not? ;) Thanks, Rusty.