From mboxrd@z Thu Jan 1 00:00:00 1970 From: Maarten Lankhorst Subject: Re: [PATCH] dma-buf/sync_file: only enable fence signalling during wait Date: Sun, 10 Jul 2016 11:15:52 +0200 Message-ID: <183b15e0-3072-6aa2-7d35-002c20752e0e@linux.intel.com> References: <1467992691-12442-1-git-send-email-gustavo@padovan.org> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by gabe.freedesktop.org (Postfix) with ESMTP id E46366E058 for ; Sun, 10 Jul 2016 09:15:56 +0000 (UTC) In-Reply-To: <1467992691-12442-1-git-send-email-gustavo@padovan.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" To: Gustavo Padovan , dri-devel@lists.freedesktop.org Cc: marcheu@google.com, Daniel Stone , seanpaul@google.com, Daniel Vetter , linux-kernel@vger.kernel.org, laurent.pinchart@ideasonboard.com, Gustavo Padovan , John Harrison , m.chehab@samsung.com List-Id: dri-devel@lists.freedesktop.org T3AgMDgtMDctMTYgb20gMTc6NDQgc2NocmVlZiBHdXN0YXZvIFBhZG92YW46Cj4gRnJvbTogR3Vz dGF2byBQYWRvdmFuIDxndXN0YXZvLnBhZG92YW5AY29sbGFib3JhLmNvLnVrPgo+Cj4gU2lnbmFs bGluZyBkb2Vzbid0IG5lZWQgdG8gYmUgZW5hYmxlZCBhdCBzeW5jX2ZpbGUgY3JlYXRpb24sIGl0 IGlzIG9ubHkKPiByZXF1aXJlZCBpZiB1c2Vyc3BhY2Ugd2FpdGluZyB0aGUgZmVuY2UgdG8gc2ln bmFsIHRocm91Z2ggcG9sbCgpLgo+Cj4gVGh1cyB3ZSBkZWxheSBmZW5jZV9hZGRfY2FsbGJhY2so KSB1bnRpbCBwb2xsIGlzIGNhbGxlZC4gSXQgb25seSBhZGRzIHRoZQo+IGNhbGxiYWNrIHRoZSBm aXJzdCB0aW1lIHBvbGwoKSBpcyBjYWxsZWQuIFRoaXMgYXZvaWQgcmUtYWRkaW5nIHRoZSBzYW1l Cj4gY2FsbGJhY2sgbXVsdGlwbGUgdGltZXMuCj4KPiB2MjogcmViYXNlIGFuZCB1cGRhdGUgdG8g d29yayB3aXRoIG5ldyBmZW5jZSBzdXBwb3J0IGZvciBzeW5jX2ZpbGUKPgo+IFNpZ25lZC1vZmYt Ynk6IEd1c3Rhdm8gUGFkb3ZhbiA8Z3VzdGF2by5wYWRvdmFuQGNvbGxhYm9yYS5jby51az4KPiAt LS0KPiBUaGlzIHBhdGNoIGFwcGxpZXMgb24gdG9wIG9mIG15IGxhdGVzdCBzeW5jX2ZpbGUgY2hh bmdlcyB0byBzdXBwb3J0Cj4gZmVuY2VfYXJyYXk6IGh0dHBzOi8vbGttbC5vcmcvbGttbC8yMDE2 LzcvNC81MzQKPgo+ICBkcml2ZXJzL2RtYS1idWYvc3luY19maWxlLmMgfCAyMyArKysrKysrKysr KysrKy0tLS0tLS0tLQo+ICBpbmNsdWRlL2xpbnV4L3N5bmNfZmlsZS5oICAgfCAgMiArKwo+ICAy IGZpbGVzIGNoYW5nZWQsIDE2IGluc2VydGlvbnMoKyksIDkgZGVsZXRpb25zKC0pCj4KPiBkaWZm IC0tZ2l0IGEvZHJpdmVycy9kbWEtYnVmL3N5bmNfZmlsZS5jIGIvZHJpdmVycy9kbWEtYnVmL3N5 bmNfZmlsZS5jCj4gaW5kZXggNjFhNjg3Yy4uMWRiNGE2NCAxMDA2NDQKPiAtLS0gYS9kcml2ZXJz L2RtYS1idWYvc3luY19maWxlLmMKPiArKysgYi9kcml2ZXJzL2RtYS1idWYvc3luY19maWxlLmMK PiBAQCAtODYsOCArODYsNiBAQCBzdHJ1Y3Qgc3luY19maWxlICpzeW5jX2ZpbGVfY3JlYXRlKHN0 cnVjdCBmZW5jZSAqZmVuY2UpCj4gIAkJIGZlbmNlLT5vcHMtPmdldF90aW1lbGluZV9uYW1lKGZl bmNlKSwgZmVuY2UtPmNvbnRleHQsCj4gIAkJIGZlbmNlLT5zZXFubyk7Cj4gIAo+IC0JZmVuY2Vf YWRkX2NhbGxiYWNrKGZlbmNlLCAmc3luY19maWxlLT5jYiwgZmVuY2VfY2hlY2tfY2JfZnVuYyk7 Cj4gLQo+ICAJcmV0dXJuIHN5bmNfZmlsZTsKPiAgfQo+ICBFWFBPUlRfU1lNQk9MKHN5bmNfZmls ZV9jcmVhdGUpOwo+IEBAIC0yNjksOSArMjY3LDYgQEAgc3RhdGljIHN0cnVjdCBzeW5jX2ZpbGUg KnN5bmNfZmlsZV9tZXJnZShjb25zdCBjaGFyICpuYW1lLCBzdHJ1Y3Qgc3luY19maWxlICphLAo+ ICAJCWdvdG8gZXJyOwo+ICAJfQo+ICAKPiAtCWZlbmNlX2FkZF9jYWxsYmFjayhzeW5jX2ZpbGUt PmZlbmNlLCAmc3luY19maWxlLT5jYiwKPiAtCQkJICAgZmVuY2VfY2hlY2tfY2JfZnVuYyk7Cj4g LQo+ICAJc3RybGNweShzeW5jX2ZpbGUtPm5hbWUsIG5hbWUsIHNpemVvZihzeW5jX2ZpbGUtPm5h bWUpKTsKPiAgCXJldHVybiBzeW5jX2ZpbGU7Cj4gIAo+IEBAIC0yODYsNyArMjgxLDYgQEAgc3Rh dGljIHZvaWQgc3luY19maWxlX2ZyZWUoc3RydWN0IGtyZWYgKmtyZWYpCj4gIAlzdHJ1Y3Qgc3lu Y19maWxlICpzeW5jX2ZpbGUgPSBjb250YWluZXJfb2Yoa3JlZiwgc3RydWN0IHN5bmNfZmlsZSwK PiAgCQkJCQkJICAgICBrcmVmKTsKPiAgCj4gLQlmZW5jZV9yZW1vdmVfY2FsbGJhY2soc3luY19m aWxlLT5mZW5jZSwgJnN5bmNfZmlsZS0+Y2IpOwo+ICAJZmVuY2VfcHV0KHN5bmNfZmlsZS0+ZmVu Y2UpOwo+ICAJa2ZyZWUoc3luY19maWxlKTsKPiAgfQo+IEBAIC0zMDYsMTMgKzMwMCwyNCBAQCBz dGF0aWMgdW5zaWduZWQgaW50IHN5bmNfZmlsZV9wb2xsKHN0cnVjdCBmaWxlICpmaWxlLCBwb2xs X3RhYmxlICp3YWl0KQo+ICAKPiAgCXBvbGxfd2FpdChmaWxlLCAmc3luY19maWxlLT53cSwgd2Fp dCk7Cj4gIAo+ICsJaWYgKCFzeW5jX2ZpbGUtPmVuYWJsZWQpIHsKPiArCQlmZW5jZV9hZGRfY2Fs bGJhY2soc3luY19maWxlLT5mZW5jZSwgJnN5bmNfZmlsZS0+Y2IsCj4gKwkJCQkgICBmZW5jZV9j aGVja19jYl9mdW5jKTsKPiArCQlzeW5jX2ZpbGUtPmVuYWJsZWQgPSB0cnVlOwo+ICsJfQpXb24n dCB0aGlzIGJsb3cgdXAgY29tcGxldGVseSB3aXRoIDIgdGhyZWFkcyBwb2xsaW5nIGF0IHRoZSBz YW1lIHRpbWU/Cgp+TWFhcnRlbgpfX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fXwpkcmktZGV2ZWwgbWFpbGluZyBsaXN0CmRyaS1kZXZlbEBsaXN0cy5mcmVlZGVz a3RvcC5vcmcKaHR0cHM6Ly9saXN0cy5mcmVlZGVza3RvcC5vcmcvbWFpbG1hbi9saXN0aW5mby9k cmktZGV2ZWwK From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757008AbcGJJP7 (ORCPT ); Sun, 10 Jul 2016 05:15:59 -0400 Received: from mga11.intel.com ([192.55.52.93]:23234 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750824AbcGJJP5 (ORCPT ); Sun, 10 Jul 2016 05:15:57 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.28,340,1464678000"; d="scan'208";a="732095424" Subject: Re: [PATCH] dma-buf/sync_file: only enable fence signalling during wait To: Gustavo Padovan , dri-devel@lists.freedesktop.org References: <1467992691-12442-1-git-send-email-gustavo@padovan.org> Cc: linux-kernel@vger.kernel.org, Daniel Stone , Daniel Vetter , Rob Clark , Greg Hackmann , John Harrison , laurent.pinchart@ideasonboard.com, seanpaul@google.com, marcheu@google.com, m.chehab@samsung.com, Sumit Semwal , Gustavo Padovan From: Maarten Lankhorst Message-ID: <183b15e0-3072-6aa2-7d35-002c20752e0e@linux.intel.com> Date: Sun, 10 Jul 2016 11:15:52 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.1.1 MIME-Version: 1.0 In-Reply-To: <1467992691-12442-1-git-send-email-gustavo@padovan.org> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Op 08-07-16 om 17:44 schreef Gustavo Padovan: > From: Gustavo Padovan > > Signalling doesn't need to be enabled at sync_file creation, it is only > required if userspace waiting the fence to signal through poll(). > > Thus we delay fence_add_callback() until poll is called. It only adds the > callback the first time poll() is called. This avoid re-adding the same > callback multiple times. > > v2: rebase and update to work with new fence support for sync_file > > Signed-off-by: Gustavo Padovan > --- > This patch applies on top of my latest sync_file changes to support > fence_array: https://lkml.org/lkml/2016/7/4/534 > > drivers/dma-buf/sync_file.c | 23 ++++++++++++++--------- > include/linux/sync_file.h | 2 ++ > 2 files changed, 16 insertions(+), 9 deletions(-) > > diff --git a/drivers/dma-buf/sync_file.c b/drivers/dma-buf/sync_file.c > index 61a687c..1db4a64 100644 > --- a/drivers/dma-buf/sync_file.c > +++ b/drivers/dma-buf/sync_file.c > @@ -86,8 +86,6 @@ struct sync_file *sync_file_create(struct fence *fence) > fence->ops->get_timeline_name(fence), fence->context, > fence->seqno); > > - fence_add_callback(fence, &sync_file->cb, fence_check_cb_func); > - > return sync_file; > } > EXPORT_SYMBOL(sync_file_create); > @@ -269,9 +267,6 @@ static struct sync_file *sync_file_merge(const char *name, struct sync_file *a, > goto err; > } > > - fence_add_callback(sync_file->fence, &sync_file->cb, > - fence_check_cb_func); > - > strlcpy(sync_file->name, name, sizeof(sync_file->name)); > return sync_file; > > @@ -286,7 +281,6 @@ static void sync_file_free(struct kref *kref) > struct sync_file *sync_file = container_of(kref, struct sync_file, > kref); > > - fence_remove_callback(sync_file->fence, &sync_file->cb); > fence_put(sync_file->fence); > kfree(sync_file); > } > @@ -306,13 +300,24 @@ static unsigned int sync_file_poll(struct file *file, poll_table *wait) > > poll_wait(file, &sync_file->wq, wait); > > + if (!sync_file->enabled) { > + fence_add_callback(sync_file->fence, &sync_file->cb, > + fence_check_cb_func); > + sync_file->enabled = true; > + } Won't this blow up completely with 2 threads polling at the same time? ~Maarten