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=-10.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 E5FE0C4338F for ; Tue, 17 Aug 2021 13:17:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C360160F39 for ; Tue, 17 Aug 2021 13:17:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239902AbhHQNSU (ORCPT ); Tue, 17 Aug 2021 09:18:20 -0400 Received: from Galois.linutronix.de ([193.142.43.55]:60492 "EHLO galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237615AbhHQNSR (ORCPT ); Tue, 17 Aug 2021 09:18:17 -0400 Date: Tue, 17 Aug 2021 15:17:41 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1629206263; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=u3bt7TzW/938vZc/Mx6WF9QB04VmQHL6ysb80Oa7dCU=; b=rHUhQGamZA/XTF2+yWTJCtSqxRY02aDK/gmO1rKZenVH8IIhpft/EML9N9ceMRauqsMAZk O5hgHIWwc+HG1c6Y5isAvJ+wTTm/HQ8rOAtuepIY4nS6GEUxcJIdFGpNftqy+EjtammeQw B+5C8NUtjBHwgN21ooH0vigZvij79Dzacvr/kIrF2hHT5T/xA4CamQ5hGrK1tjcMpNtZGc iuGKJsto9RL9OfBxa2BIr1EJKy2I645Inp39ilJJHAgQ64cnO2sy07mDsY43uAVHpXpbjn Ja3r5Dn7hq/edYQr8jUnAKceBjjJHk283doB1mlO2ydOQycIJ0NJY4a1fg2APA== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1629206263; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=u3bt7TzW/938vZc/Mx6WF9QB04VmQHL6ysb80Oa7dCU=; b=e/qbVWtUO9Hb0fF4J3nTit/oOj4iNHDmmURhYHc471ibAr9MAo7vRtYus6cs0WDOgUMRkU H5zJq8vhbw4FrxDA== From: Sebastian Andrzej Siewior To: Valentin Schneider Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, rcu@vger.kernel.org, linux-rt-users@vger.kernel.org, Catalin Marinas , Will Deacon , Ingo Molnar , Peter Zijlstra , Thomas Gleixner , Steven Rostedt , Daniel Bristot de Oliveira , "Paul E. McKenney" , Frederic Weisbecker , Josh Triplett , Mathieu Desnoyers , Davidlohr Bueso , Lai Jiangshan , Joel Fernandes , Anshuman Khandual , Vincenzo Frascino , Steven Price , Ard Biesheuvel , Boqun Feng , Mike Galbraith Subject: Re: [PATCH v3 1/4] rcutorture: Don't disable softirqs with preemption disabled when PREEMPT_RT Message-ID: <20210817131741.evduh4fw7vyv2dzt@linutronix.de> References: <20210811201354.1976839-1-valentin.schneider@arm.com> <20210811201354.1976839-2-valentin.schneider@arm.com> <20210817121345.5iyj5epemczn3a52@linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable In-Reply-To: <20210817121345.5iyj5epemczn3a52@linutronix.de> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2021-08-17 14:13:47 [+0200], To Valentin Schneider wrote: > > index eecd1caef71d..4f3db1d3170d 100644 > > --- a/kernel/rcu/rcutorture.c > > +++ b/kernel/rcu/rcutorture.c > > @@ -1548,6 +1548,8 @@ rcutorture_extend_mask(int oldmask, struct tortur= e_random_state *trsp) > > * them on non-RT. > > */ > > if (IS_ENABLED(CONFIG_PREEMPT_RT)) { > > + /* Can't disable bh in atomic context under PREEMPT_RT */ > > + mask &=3D ~(RCUTORTURE_RDR_ATOM_BH | RCUTORTURE_RDR_ATOM_RBH); >=20 > Let me stare at this=E2=80=A6 I would fold this --- a/kernel/rcu/rcutorture.c +++ b/kernel/rcu/rcutorture.c @@ -1549,6 +1549,13 @@ rcutorture_extend_mask(int oldmask, stru */ if (IS_ENABLED(CONFIG_PREEMPT_RT)) { /* + * Can't disable bh in atomic context if bh was already + * disabled by another task on the same CPU. Instead of + * attempting to track this, just avoid disabling bh in atomic + * context. + */ + mask &=3D ~atomic_bhs; + /* * Can't release the outermost rcu lock in an irq disabled * section without preemption also being disabled, if irqs * had ever been enabled during this RCU critical section @@ -1559,16 +1566,6 @@ rcutorture_extend_mask(int oldmask, stru !(mask & preempts)) mask |=3D RCUTORTURE_RDR_RCU; =20 - /* Can't modify atomic bh in non-atomic context */ - if ((oldmask & atomic_bhs) && (mask & atomic_bhs) && - !(mask & preempts_irq)) { - mask |=3D oldmask & preempts_irq; - if (mask & RCUTORTURE_RDR_IRQ) - mask |=3D oldmask & tmp; - } - if ((mask & atomic_bhs) && !(mask & preempts_irq)) - mask |=3D RCUTORTURE_RDR_PREEMPT; - /* Can't modify non-atomic bh in atomic context */ tmp =3D nonatomic_bhs; if (oldmask & preempts_irq) into the original patch and forward it upstream=E2=80=A6 Sebastian 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=-9.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,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 D722CC432BE for ; Tue, 17 Aug 2021 13:20:02 +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 A3FB560F35 for ; Tue, 17 Aug 2021 13:20:02 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org A3FB560F35 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linutronix.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=mklQL4rubpTXKekaVIH6IlftYwfpsqLM76Hk3UJTjSM=; b=Fx9BxEPldRdZKI /dZ+YGiXhPjN7uGkCxY7dkiSm3/U2kRc58Lk22YJ3cZnoIgBBK88vXbJ5iKQmi5/DZbAINLVk7gNu 9V3MqNJq1QUZKLa0pfPzLZ0Lz+gfihPr0bBeK1gWpyG5sddYClTFgtACcgL4QSVr3OhTz7eWwPbt1 UHv8sNKjewdmbFSqqEbRwqY44C104FC6UPW2cJdifOhBTpA2auvi0AFA/z9n0i6fxBEH8Tw0c++df w+MQo7selwKNVhvVEa59UPJ76MzHU3lkZ36EjVD+drp3zm14Ce8x78Uc4Y6dmctjYRYIjySecEdFH dO0iIQLfKag+Y2VvkHPw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1mFyyW-002Zdf-ED; Tue, 17 Aug 2021 13:17:52 +0000 Received: from galois.linutronix.de ([193.142.43.55]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1mFyyP-002ZcN-Lo for linux-arm-kernel@lists.infradead.org; Tue, 17 Aug 2021 13:17:49 +0000 Date: Tue, 17 Aug 2021 15:17:41 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1629206263; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=u3bt7TzW/938vZc/Mx6WF9QB04VmQHL6ysb80Oa7dCU=; b=rHUhQGamZA/XTF2+yWTJCtSqxRY02aDK/gmO1rKZenVH8IIhpft/EML9N9ceMRauqsMAZk O5hgHIWwc+HG1c6Y5isAvJ+wTTm/HQ8rOAtuepIY4nS6GEUxcJIdFGpNftqy+EjtammeQw B+5C8NUtjBHwgN21ooH0vigZvij79Dzacvr/kIrF2hHT5T/xA4CamQ5hGrK1tjcMpNtZGc iuGKJsto9RL9OfBxa2BIr1EJKy2I645Inp39ilJJHAgQ64cnO2sy07mDsY43uAVHpXpbjn Ja3r5Dn7hq/edYQr8jUnAKceBjjJHk283doB1mlO2ydOQycIJ0NJY4a1fg2APA== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1629206263; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=u3bt7TzW/938vZc/Mx6WF9QB04VmQHL6ysb80Oa7dCU=; b=e/qbVWtUO9Hb0fF4J3nTit/oOj4iNHDmmURhYHc471ibAr9MAo7vRtYus6cs0WDOgUMRkU H5zJq8vhbw4FrxDA== From: Sebastian Andrzej Siewior To: Valentin Schneider Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, rcu@vger.kernel.org, linux-rt-users@vger.kernel.org, Catalin Marinas , Will Deacon , Ingo Molnar , Peter Zijlstra , Thomas Gleixner , Steven Rostedt , Daniel Bristot de Oliveira , "Paul E. McKenney" , Frederic Weisbecker , Josh Triplett , Mathieu Desnoyers , Davidlohr Bueso , Lai Jiangshan , Joel Fernandes , Anshuman Khandual , Vincenzo Frascino , Steven Price , Ard Biesheuvel , Boqun Feng , Mike Galbraith Subject: Re: [PATCH v3 1/4] rcutorture: Don't disable softirqs with preemption disabled when PREEMPT_RT Message-ID: <20210817131741.evduh4fw7vyv2dzt@linutronix.de> References: <20210811201354.1976839-1-valentin.schneider@arm.com> <20210811201354.1976839-2-valentin.schneider@arm.com> <20210817121345.5iyj5epemczn3a52@linutronix.de> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20210817121345.5iyj5epemczn3a52@linutronix.de> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210817_061745_905650_B20D453F X-CRM114-Status: GOOD ( 13.66 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org T24gMjAyMS0wOC0xNyAxNDoxMzo0NyBbKzAyMDBdLCBUbyBWYWxlbnRpbiBTY2huZWlkZXIgd3Jv dGU6Cj4gPiBpbmRleCBlZWNkMWNhZWY3MWQuLjRmM2RiMWQzMTcwZCAxMDA2NDQKPiA+IC0tLSBh L2tlcm5lbC9yY3UvcmN1dG9ydHVyZS5jCj4gPiArKysgYi9rZXJuZWwvcmN1L3JjdXRvcnR1cmUu Ywo+ID4gQEAgLTE1NDgsNiArMTU0OCw4IEBAIHJjdXRvcnR1cmVfZXh0ZW5kX21hc2soaW50IG9s ZG1hc2ssIHN0cnVjdCB0b3J0dXJlX3JhbmRvbV9zdGF0ZSAqdHJzcCkKPiA+ICAJICogdGhlbSBv biBub24tUlQuCj4gPiAgCSAqLwo+ID4gIAlpZiAoSVNfRU5BQkxFRChDT05GSUdfUFJFRU1QVF9S VCkpIHsKPiA+ICsJCS8qIENhbid0IGRpc2FibGUgYmggaW4gYXRvbWljIGNvbnRleHQgdW5kZXIg UFJFRU1QVF9SVCAqLwo+ID4gKwkJbWFzayAmPSB+KFJDVVRPUlRVUkVfUkRSX0FUT01fQkggfCBS Q1VUT1JUVVJFX1JEUl9BVE9NX1JCSCk7Cj4gCj4gTGV0IG1lIHN0YXJlIGF0IHRoaXPigKYKCkkg d291bGQgZm9sZCB0aGlzCgotLS0gYS9rZXJuZWwvcmN1L3JjdXRvcnR1cmUuYworKysgYi9rZXJu ZWwvcmN1L3JjdXRvcnR1cmUuYwpAQCAtMTU0OSw2ICsxNTQ5LDEzIEBAIHJjdXRvcnR1cmVfZXh0 ZW5kX21hc2soaW50IG9sZG1hc2ssIHN0cnUKIAkgKi8KIAlpZiAoSVNfRU5BQkxFRChDT05GSUdf UFJFRU1QVF9SVCkpIHsKIAkJLyoKKwkJICogQ2FuJ3QgZGlzYWJsZSBiaCBpbiBhdG9taWMgY29u dGV4dCBpZiBiaCB3YXMgYWxyZWFkeQorCQkgKiBkaXNhYmxlZCBieSBhbm90aGVyIHRhc2sgb24g dGhlIHNhbWUgQ1BVLiBJbnN0ZWFkIG9mCisJCSAqIGF0dGVtcHRpbmcgdG8gdHJhY2sgdGhpcywg anVzdCBhdm9pZCBkaXNhYmxpbmcgYmggaW4gYXRvbWljCisJCSAqIGNvbnRleHQuCisJCSAqLwor CQltYXNrICY9IH5hdG9taWNfYmhzOworCQkvKgogCQkgKiBDYW4ndCByZWxlYXNlIHRoZSBvdXRl cm1vc3QgcmN1IGxvY2sgaW4gYW4gaXJxIGRpc2FibGVkCiAJCSAqIHNlY3Rpb24gd2l0aG91dCBw cmVlbXB0aW9uIGFsc28gYmVpbmcgZGlzYWJsZWQsIGlmIGlycXMKIAkJICogaGFkIGV2ZXIgYmVl biBlbmFibGVkIGR1cmluZyB0aGlzIFJDVSBjcml0aWNhbCBzZWN0aW9uCkBAIC0xNTU5LDE2ICsx NTY2LDYgQEAgcmN1dG9ydHVyZV9leHRlbmRfbWFzayhpbnQgb2xkbWFzaywgc3RydQogCQkgICAg IShtYXNrICYgcHJlZW1wdHMpKQogCQkJbWFzayB8PSBSQ1VUT1JUVVJFX1JEUl9SQ1U7CiAKLQkJ LyogQ2FuJ3QgbW9kaWZ5IGF0b21pYyBiaCBpbiBub24tYXRvbWljIGNvbnRleHQgKi8KLQkJaWYg KChvbGRtYXNrICYgYXRvbWljX2JocykgJiYgKG1hc2sgJiBhdG9taWNfYmhzKSAmJgotCQkgICAg IShtYXNrICYgcHJlZW1wdHNfaXJxKSkgewotCQkJbWFzayB8PSBvbGRtYXNrICYgcHJlZW1wdHNf aXJxOwotCQkJaWYgKG1hc2sgJiBSQ1VUT1JUVVJFX1JEUl9JUlEpCi0JCQkJbWFzayB8PSBvbGRt YXNrICYgdG1wOwotCQl9Ci0JCWlmICgobWFzayAmIGF0b21pY19iaHMpICYmICEobWFzayAmIHBy ZWVtcHRzX2lycSkpCi0JCQltYXNrIHw9IFJDVVRPUlRVUkVfUkRSX1BSRUVNUFQ7Ci0KIAkJLyog Q2FuJ3QgbW9kaWZ5IG5vbi1hdG9taWMgYmggaW4gYXRvbWljIGNvbnRleHQgKi8KIAkJdG1wID0g bm9uYXRvbWljX2JoczsKIAkJaWYgKG9sZG1hc2sgJiBwcmVlbXB0c19pcnEpCgppbnRvIHRoZSBv cmlnaW5hbCBwYXRjaCBhbmQgZm9yd2FyZCBpdCB1cHN0cmVhbeKApgoKU2ViYXN0aWFuCgpfX19f X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fXwpsaW51eC1hcm0ta2Vy bmVsIG1haWxpbmcgbGlzdApsaW51eC1hcm0ta2VybmVsQGxpc3RzLmluZnJhZGVhZC5vcmcKaHR0 cDovL2xpc3RzLmluZnJhZGVhZC5vcmcvbWFpbG1hbi9saXN0aW5mby9saW51eC1hcm0ta2VybmVs Cg==