From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id DAC6DC43387 for ; Wed, 2 Jan 2019 10:55:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AFCEA2171F for ; Wed, 2 Jan 2019 10:55:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727631AbfABKzZ convert rfc822-to-8bit (ORCPT ); Wed, 2 Jan 2019 05:55:25 -0500 Received: from mail.bootlin.com ([62.4.15.54]:37516 "EHLO mail.bootlin.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727294AbfABKzZ (ORCPT ); Wed, 2 Jan 2019 05:55:25 -0500 Received: by mail.bootlin.com (Postfix, from userid 110) id DC8EF207B0; Wed, 2 Jan 2019 11:55:22 +0100 (CET) Received: from xps13 (aaubervilliers-681-1-29-148.w90-88.abo.wanadoo.fr [90.88.149.148]) by mail.bootlin.com (Postfix) with ESMTPSA id 87F7A206A6; Wed, 2 Jan 2019 11:55:22 +0100 (CET) Date: Wed, 2 Jan 2019 11:55:22 +0100 From: Miquel Raynal To: Stephen Boyd Cc: Michael Turquette , Russell King , linux-clk@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Thomas Petazzoni , Antoine Tenart , Maxime Chevallier , Gregory Clement , Nadav Haklai Subject: Re: [PATCH v3 1/4] clk: core: clarify the check for runtime PM Message-ID: <20190102115522.2d7a1c37@xps13> In-Reply-To: <154534015908.79149.14109221006631310404@swboyd.mtv.corp.google.com> References: <20181204192440.12125-1-miquel.raynal@bootlin.com> <20181204192440.12125-2-miquel.raynal@bootlin.com> <154517780935.238328.764268020422357561@swboyd.mtv.corp.google.com> <20181219090331.4c8c4852@xps13> <154534015908.79149.14109221006631310404@swboyd.mtv.corp.google.com> Organization: Bootlin X-Mailer: Claws Mail 3.17.1 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-clk-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-clk@vger.kernel.org Hi Stephen, Stephen Boyd wrote on Thu, 20 Dec 2018 13:09:19 -0800: > Quoting Miquel Raynal (2018-12-19 00:03:31) > > Hi Stephen, > > > > Stephen Boyd wrote on Tue, 18 Dec 2018 16:03:29 > > -0800: > > > > > Quoting Miquel Raynal (2018-12-04 11:24:37) > > > > Currently, the core->dev entry is populated only if runtime PM is > > > > enabled. Doing so prevents accessing the device structure in any > > > > case. > > > > > > > > Keep the same logic but instead of using the presence of core->dev as > > > > the only condition, also check the status of > > > > pm_runtime_enabled(). Then, we can set the core->dev pointer at any > > > > time as long as a device structure is available. > > > > > > > > This change will help supporting device links in the clock subsystem. > > > > > > > > Signed-off-by: Miquel Raynal > > > > --- > > > > drivers/clk/clk.c | 11 +++++------ > > > > 1 file changed, 5 insertions(+), 6 deletions(-) > > > > > > > > diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c > > > > index af011974d4ec..b799347c5fd6 100644 > > > > --- a/drivers/clk/clk.c > > > > +++ b/drivers/clk/clk.c > > > > @@ -97,7 +97,7 @@ static int clk_pm_runtime_get(struct clk_core *core) > > > > { > > > > int ret = 0; > > > > > > > > - if (!core->dev) > > > > + if (!core->dev || !pm_runtime_enabled(core->dev)) > > > > > > This looks potentially dangerous. What if runtime PM is disabled for the > > > clk when this function is called? Shouldn't we just stash a bool away in > > > the clk_core structure when it's registered? And then we can replace the > > > check for !core->dev with a check for 'core->rpm_enabled' instead. That > > > would be a more exact transformation. > > > > Sure, I'll do that if you think there is a danger. > > I've made the change and pushed it out to the clk tree. I'm working on > some patches to change how we do parent lookups and reworking clk_get() > in the process. Take a look so we don't duplicate efforts. The code > isn't complete, but I hope to finish soon. Your device links patches can > build upon this. > > git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux.git clk-parent-rewrite > Sorry for the delay and thanks for the update. I have been preempted by another issue, I will switch to clocks and propose something ASAP. Thanks, Miquèl From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-14.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 92EB1C43387 for ; Wed, 2 Jan 2019 10:55:30 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 504922171F for ; Wed, 2 Jan 2019 10:55:30 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="R71CaLoc" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 504922171F Authentication-Results: mail.kernel.org; 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Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1geeBN-0008Rr-KT; Wed, 02 Jan 2019 10:55:29 +0000 Received: from mail.bootlin.com ([62.4.15.54]) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1geeBJ-0008Pw-Qv for linux-arm-kernel@lists.infradead.org; Wed, 02 Jan 2019 10:55:27 +0000 Received: by mail.bootlin.com (Postfix, from userid 110) id DC8EF207B0; Wed, 2 Jan 2019 11:55:22 +0100 (CET) Received: from xps13 (aaubervilliers-681-1-29-148.w90-88.abo.wanadoo.fr [90.88.149.148]) by mail.bootlin.com (Postfix) with ESMTPSA id 87F7A206A6; Wed, 2 Jan 2019 11:55:22 +0100 (CET) Date: Wed, 2 Jan 2019 11:55:22 +0100 From: Miquel Raynal To: Stephen Boyd Subject: Re: [PATCH v3 1/4] clk: core: clarify the check for runtime PM Message-ID: <20190102115522.2d7a1c37@xps13> In-Reply-To: <154534015908.79149.14109221006631310404@swboyd.mtv.corp.google.com> References: <20181204192440.12125-1-miquel.raynal@bootlin.com> <20181204192440.12125-2-miquel.raynal@bootlin.com> <154517780935.238328.764268020422357561@swboyd.mtv.corp.google.com> <20181219090331.4c8c4852@xps13> <154534015908.79149.14109221006631310404@swboyd.mtv.corp.google.com> Organization: Bootlin X-Mailer: Claws Mail 3.17.1 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190102_025526_145164_D6E94384 X-CRM114-Status: GOOD ( 26.76 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Gregory Clement , Antoine Tenart , Michael Turquette , linux-kernel@vger.kernel.org, Russell King , Nadav Haklai , Thomas Petazzoni , Maxime Chevallier , linux-clk@vger.kernel.org, linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org SGkgU3RlcGhlbiwKClN0ZXBoZW4gQm95ZCA8c2JveWRAa2VybmVsLm9yZz4gd3JvdGUgb24gVGh1 LCAyMCBEZWMgMjAxOCAxMzowOToxOQotMDgwMDoKCj4gUXVvdGluZyBNaXF1ZWwgUmF5bmFsICgy MDE4LTEyLTE5IDAwOjAzOjMxKQo+ID4gSGkgU3RlcGhlbiwKPiA+IAo+ID4gU3RlcGhlbiBCb3lk IDxzYm95ZEBrZXJuZWwub3JnPiB3cm90ZSBvbiBUdWUsIDE4IERlYyAyMDE4IDE2OjAzOjI5Cj4g PiAtMDgwMDoKPiA+ICAgCj4gPiA+IFF1b3RpbmcgTWlxdWVsIFJheW5hbCAoMjAxOC0xMi0wNCAx MToyNDozNykgIAo+ID4gPiA+IEN1cnJlbnRseSwgdGhlIGNvcmUtPmRldiBlbnRyeSBpcyBwb3B1 bGF0ZWQgb25seSBpZiBydW50aW1lIFBNIGlzCj4gPiA+ID4gZW5hYmxlZC4gRG9pbmcgc28gcHJl dmVudHMgYWNjZXNzaW5nIHRoZSBkZXZpY2Ugc3RydWN0dXJlIGluIGFueQo+ID4gPiA+IGNhc2Uu Cj4gPiA+ID4gCj4gPiA+ID4gS2VlcCB0aGUgc2FtZSBsb2dpYyBidXQgaW5zdGVhZCBvZiB1c2lu ZyB0aGUgcHJlc2VuY2Ugb2YgY29yZS0+ZGV2IGFzCj4gPiA+ID4gdGhlIG9ubHkgY29uZGl0aW9u LCBhbHNvIGNoZWNrIHRoZSBzdGF0dXMgb2YKPiA+ID4gPiBwbV9ydW50aW1lX2VuYWJsZWQoKS4g VGhlbiwgd2UgY2FuIHNldCB0aGUgY29yZS0+ZGV2IHBvaW50ZXIgYXQgYW55Cj4gPiA+ID4gdGlt ZSBhcyBsb25nIGFzIGEgZGV2aWNlIHN0cnVjdHVyZSBpcyBhdmFpbGFibGUuCj4gPiA+ID4gCj4g PiA+ID4gVGhpcyBjaGFuZ2Ugd2lsbCBoZWxwIHN1cHBvcnRpbmcgZGV2aWNlIGxpbmtzIGluIHRo ZSBjbG9jayBzdWJzeXN0ZW0uCj4gPiA+ID4gCj4gPiA+ID4gU2lnbmVkLW9mZi1ieTogTWlxdWVs IFJheW5hbCA8bWlxdWVsLnJheW5hbEBib290bGluLmNvbT4KPiA+ID4gPiAtLS0KPiA+ID4gPiAg ZHJpdmVycy9jbGsvY2xrLmMgfCAxMSArKysrKy0tLS0tLQo+ID4gPiA+ICAxIGZpbGUgY2hhbmdl ZCwgNSBpbnNlcnRpb25zKCspLCA2IGRlbGV0aW9ucygtKQo+ID4gPiA+IAo+ID4gPiA+IGRpZmYg LS1naXQgYS9kcml2ZXJzL2Nsay9jbGsuYyBiL2RyaXZlcnMvY2xrL2Nsay5jCj4gPiA+ID4gaW5k ZXggYWYwMTE5NzRkNGVjLi5iNzk5MzQ3YzVmZDYgMTAwNjQ0Cj4gPiA+ID4gLS0tIGEvZHJpdmVy cy9jbGsvY2xrLmMKPiA+ID4gPiArKysgYi9kcml2ZXJzL2Nsay9jbGsuYwo+ID4gPiA+IEBAIC05 Nyw3ICs5Nyw3IEBAIHN0YXRpYyBpbnQgY2xrX3BtX3J1bnRpbWVfZ2V0KHN0cnVjdCBjbGtfY29y ZSAqY29yZSkKPiA+ID4gPiAgewo+ID4gPiA+ICAgICAgICAgaW50IHJldCA9IDA7Cj4gPiA+ID4g IAo+ID4gPiA+IC0gICAgICAgaWYgKCFjb3JlLT5kZXYpCj4gPiA+ID4gKyAgICAgICBpZiAoIWNv cmUtPmRldiB8fCAhcG1fcnVudGltZV9lbmFibGVkKGNvcmUtPmRldikpICAgIAo+ID4gPiAKPiA+ ID4gVGhpcyBsb29rcyBwb3RlbnRpYWxseSBkYW5nZXJvdXMuIFdoYXQgaWYgcnVudGltZSBQTSBp cyBkaXNhYmxlZCBmb3IgdGhlCj4gPiA+IGNsayB3aGVuIHRoaXMgZnVuY3Rpb24gaXMgY2FsbGVk PyBTaG91bGRuJ3Qgd2UganVzdCBzdGFzaCBhIGJvb2wgYXdheSBpbgo+ID4gPiB0aGUgY2xrX2Nv cmUgc3RydWN0dXJlIHdoZW4gaXQncyByZWdpc3RlcmVkPyBBbmQgdGhlbiB3ZSBjYW4gcmVwbGFj ZSB0aGUKPiA+ID4gY2hlY2sgZm9yICFjb3JlLT5kZXYgd2l0aCBhIGNoZWNrIGZvciAnY29yZS0+ cnBtX2VuYWJsZWQnIGluc3RlYWQuIFRoYXQKPiA+ID4gd291bGQgYmUgYSBtb3JlIGV4YWN0IHRy YW5zZm9ybWF0aW9uLiAgCj4gPiAKPiA+IFN1cmUsIEknbGwgZG8gdGhhdCBpZiB5b3UgdGhpbmsg dGhlcmUgaXMgYSBkYW5nZXIuICAKPiAKPiBJJ3ZlIG1hZGUgdGhlIGNoYW5nZSBhbmQgcHVzaGVk IGl0IG91dCB0byB0aGUgY2xrIHRyZWUuIEknbSB3b3JraW5nIG9uCj4gc29tZSBwYXRjaGVzIHRv IGNoYW5nZSBob3cgd2UgZG8gcGFyZW50IGxvb2t1cHMgYW5kIHJld29ya2luZyBjbGtfZ2V0KCkK PiBpbiB0aGUgcHJvY2Vzcy4gVGFrZSBhIGxvb2sgc28gd2UgZG9uJ3QgZHVwbGljYXRlIGVmZm9y dHMuIFRoZSBjb2RlCj4gaXNuJ3QgY29tcGxldGUsIGJ1dCBJIGhvcGUgdG8gZmluaXNoIHNvb24u IFlvdXIgZGV2aWNlIGxpbmtzIHBhdGNoZXMgY2FuCj4gYnVpbGQgdXBvbiB0aGlzLgo+IAo+ICBn aXQ6Ly9naXQua2VybmVsLm9yZy9wdWIvc2NtL2xpbnV4L2tlcm5lbC9naXQvY2xrL2xpbnV4Lmdp dCBjbGstcGFyZW50LXJld3JpdGUKPiAKClNvcnJ5IGZvciB0aGUgZGVsYXkgYW5kIHRoYW5rcyBm b3IgdGhlIHVwZGF0ZS4gSSBoYXZlIGJlZW4gcHJlZW1wdGVkIGJ5CmFub3RoZXIgaXNzdWUsIEkg d2lsbCBzd2l0Y2ggdG8gY2xvY2tzIGFuZCBwcm9wb3NlIHNvbWV0aGluZyBBU0FQLgoKClRoYW5r cywKTWlxdcOobAoKX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f X18KbGludXgtYXJtLWtlcm5lbCBtYWlsaW5nIGxpc3QKbGludXgtYXJtLWtlcm5lbEBsaXN0cy5p bmZyYWRlYWQub3JnCmh0dHA6Ly9saXN0cy5pbmZyYWRlYWQub3JnL21haWxtYW4vbGlzdGluZm8v bGludXgtYXJtLWtlcm5lbAo=