From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx0b-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7B89E31D736; Fri, 5 Sep 2025 15:53:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=148.163.158.5 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757087633; cv=none; b=mksp68x44d4FrBbLBGwggHSWiCBZOOX3LkiTczrkWmeagazODzY5OYfWwyy1dYCPoYpVvVIuMfpsQOHncvEX2xSd0LJ3+w7zb8uZ3UjzT7LVCHX7xgAzKcc1FaZVEQFaW1x/98jaRUeDgNqPMUKg0hc8g2DoT3/c149CvUtz7Ko= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757087633; c=relaxed/simple; bh=0XQFS8CyF3Pn0PNn9jiLpMCv4A/YVZphjlf8xD+vRZw=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=C1U6sWb+doigWqEhRgGIJlJwMnY3wEfC++6mr/BYtpLaE25DYge/hzyRxg9IbmJ5Ix5+B9aE8vHl/TVHLoX3B/mGPc8nnBt/x/F9pl1WmYcaut4YTh0gs7UUQHZZLYiU8Mi2oPXjnbjgneQrSo/Kb1cJ8YbNdaeIQyiQ2e76ijw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.ibm.com; spf=pass smtp.mailfrom=linux.ibm.com; dkim=pass (2048-bit key) header.d=ibm.com header.i=@ibm.com header.b=qnifUl96; arc=none smtp.client-ip=148.163.158.5 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.ibm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.ibm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=ibm.com header.i=@ibm.com header.b="qnifUl96" Received: from pps.filterd (m0356516.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 5858qiX8001199; Fri, 5 Sep 2025 15:52:50 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=cc :content-type:date:from:in-reply-to:message-id:mime-version :references:subject:to; s=pp1; bh=yrKzRKvPlqc1QwFwyTNKlG24n0S3B0 erGWAU2bVkVqg=; b=qnifUl96cq8S6mdWIUWZY6BIWU8yF2upNweBx/YvMVrUqk RurxzzOfjdHTO1vZruHBUGw3vkJ3WeEmWzLy0ib2dt0fUdi9302JluZSn5voqpb9 tt+K2LZopne4AXw3OGAsBjWP8De3MBm1hwH4/INAMOLsTRAjDmX8jUJ/gKxB4XAc KrIlZNUzwzjCaqkU+ZOpln4XrPIJTWESS5y/saIRobaltfDoOVm72NdzSHeS2nKf hGMYLo6HZzSBX5xdzjXsfqIsGIlRMWccKTKAhN9S2rP+bQ/qPKUMPRNpVA8A/v6E L8fXKTqpSJEYDa6i80pdzLQ72TamFaiRukB8PM0g== Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 48wshfcpx3-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 05 Sep 2025 15:52:50 +0000 (GMT) Received: from m0356516.ppops.net (m0356516.ppops.net [127.0.0.1]) by pps.reinject (8.18.1.12/8.18.0.8) with ESMTP id 585Fmcsp012235; Fri, 5 Sep 2025 15:52:49 GMT Received: from ppma12.dal12v.mail.ibm.com (dc.9e.1632.ip4.static.sl-reverse.com [50.22.158.220]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 48wshfcpwy-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 05 Sep 2025 15:52:49 +0000 (GMT) Received: from pps.filterd (ppma12.dal12v.mail.ibm.com [127.0.0.1]) by ppma12.dal12v.mail.ibm.com (8.18.1.2/8.18.1.2) with ESMTP id 585FmxfV019937; Fri, 5 Sep 2025 15:52:48 GMT Received: from smtprelay02.fra02v.mail.ibm.com ([9.218.2.226]) by ppma12.dal12v.mail.ibm.com (PPS) with ESMTPS id 48vbmujcy7-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 05 Sep 2025 15:52:48 +0000 Received: from smtpav05.fra02v.mail.ibm.com (smtpav05.fra02v.mail.ibm.com [10.20.54.104]) by smtprelay02.fra02v.mail.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 585Fqke750659768 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 5 Sep 2025 15:52:46 GMT Received: from smtpav05.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 8C56520043; Fri, 5 Sep 2025 15:52:46 +0000 (GMT) Received: from smtpav05.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 1DCE620040; Fri, 5 Sep 2025 15:52:45 +0000 (GMT) Received: from li-008a6a4c-3549-11b2-a85c-c5cc2836eea2.ibm.com (unknown [9.111.48.240]) by smtpav05.fra02v.mail.ibm.com (Postfix) with ESMTPS; Fri, 5 Sep 2025 15:52:45 +0000 (GMT) Date: Fri, 5 Sep 2025 17:52:43 +0200 From: Alexander Gordeev To: Kevin Brodsky Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Andreas Larsson , Andrew Morton , Boris Ostrovsky , Borislav Petkov , Catalin Marinas , Christophe Leroy , Dave Hansen , David Hildenbrand , "David S. Miller" , "H. Peter Anvin" , Ingo Molnar , Jann Horn , Juergen Gross , "Liam R. Howlett" , Lorenzo Stoakes , Madhavan Srinivasan , Michael Ellerman , Michal Hocko , Mike Rapoport , Nicholas Piggin , Peter Zijlstra , Ryan Roberts , Suren Baghdasaryan , Thomas Gleixner , Vlastimil Babka , Will Deacon , linux-arm-kernel@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, sparclinux@vger.kernel.org, xen-devel@lists.xenproject.org Subject: Re: [PATCH 5/7] powerpc/mm: support nested lazy_mmu sections Message-ID: <074ff6ab-5868-4fde-b5bb-9e17632ad817-agordeev@linux.ibm.com> References: <20250904125736.3918646-1-kevin.brodsky@arm.com> <20250904125736.3918646-6-kevin.brodsky@arm.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250904125736.3918646-6-kevin.brodsky@arm.com> X-TM-AS-GCONF: 00 X-Proofpoint-GUID: lCd6YOMsS3DuDBadSx3AqoWK9sgWIwBw X-Authority-Analysis: v=2.4 cv=do3bC0g4 c=1 sm=1 tr=0 ts=68bb0752 cx=c_pps a=bLidbwmWQ0KltjZqbj+ezA==:117 a=bLidbwmWQ0KltjZqbj+ezA==:17 a=kj9zAlcOel0A:10 a=yJojWOMRYYMA:10 a=j0AthGTrb4EvYsEn83oA:9 a=CjuIK1q_8ugA:10 X-Proofpoint-ORIG-GUID: f87PfJay9odLOn37oqVwjr2CAlcWWHn1 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjUwOTAyMDA0MCBTYWx0ZWRfX6sVQx3QDeZVb n0/AHQXDAd1IPDvrbQDAZqWNvYoji1vUEPP9JAjcx2sdZwqxFNT8P6jKDiqCdhkxMnGuyNq6xN0 S8g8X6OMzE3gSb6sI+vSPcwT7zIQgnHlzsA9jiitgokDLD2w11I2lobQd0RzFFdQVPBFq7gLH2W w3OGrenK+wBn0voMSBbmNjp1Fjlqy/CSo5Vh9PvP5VNsOgQXuA9fqz0KJ8mfFGOfUfce75STf2p eu65lI0DTVxqmjYKeyaFdLRjc3SxwtmZeh1Pe6KdSGdqawAHM6zOfs0r4Yils+ob60NU/kRnAup 7+9DLLEmBuvBzuYqwqF9czbkIes2bGJOe8p5YqMQ0X/8i+oJ9lIUH4tj2BythK5q2hT0kmdi9nq KtlUPSlt X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1117,Hydra:6.1.9,FMLib:17.12.80.40 definitions=2025-09-05_05,2025-09-04_01,2025-03-28_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 phishscore=0 clxscore=1015 impostorscore=0 bulkscore=0 suspectscore=0 malwarescore=0 spamscore=0 priorityscore=1501 adultscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.19.0-2507300000 definitions=main-2509020040 On Thu, Sep 04, 2025 at 01:57:34PM +0100, Kevin Brodsky wrote: ... > static inline lazy_mmu_state_t arch_enter_lazy_mmu_mode(void) > { > struct ppc64_tlb_batch *batch; > + int lazy_mmu_nested; > > if (radix_enabled()) > return LAZY_MMU_DEFAULT; > @@ -39,9 +40,14 @@ static inline lazy_mmu_state_t arch_enter_lazy_mmu_mode(void) > */ > preempt_disable(); > batch = this_cpu_ptr(&ppc64_tlb_batch); > - batch->active = 1; > + lazy_mmu_nested = batch->active; > > - return LAZY_MMU_DEFAULT; > + if (!lazy_mmu_nested) { Why not just? if (!batch->active) { > + batch->active = 1; > + return LAZY_MMU_DEFAULT; > + } else { > + return LAZY_MMU_NESTED; > + } > } > > static inline void arch_leave_lazy_mmu_mode(lazy_mmu_state_t state) > @@ -54,7 +60,10 @@ static inline void arch_leave_lazy_mmu_mode(lazy_mmu_state_t state) > > if (batch->index) > __flush_tlb_pending(batch); > - batch->active = 0; > + > + if (state != LAZY_MMU_NESTED) > + batch->active = 0; > + > preempt_enable(); > } Thanks!