From patchwork Wed Mar 5 10:49:24 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Valentin Schneider X-Patchwork-Id: 870744 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (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 E965021883F for ; Wed, 5 Mar 2025 10:50:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741171811; cv=none; b=qrFf4IdCglTPTHrrsl1lMiD7AvJjZSP0AjGtUAB8feNx1nGC4HdIGsl+YxrWN/JkconVYcSdL0Z7SbYrLTOEkgRzuGUnH9MsaKdYMMeZyHxIxmPmTk4ZB4TEspT0xzOW3+m728maxCaHNN4WzZCusPHrOmOCgz+eoaerW0nNF7Q= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741171811; c=relaxed/simple; bh=PGBWl9yPog/7ujlW8n28qzNSWC2BA+nZV3uoFclQnYc=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=AhjABxevnqNOQn39pkFaCXaFjOT6ZrGOdnBmw70mRl+HZGEYqe9gGs7lsYhn4Cu962kdiS+rycbwmvnX7LGABd4Pm4lXKbcDfIFgvbHceJwHIjUJZWjWdqtYUUdSvLhBCQLu8mMJsY5CL3Cwq/4cUEMmkPuXO4lCRtX0BsZCLS8= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=PAWpI523; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="PAWpI523" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1741171808; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=oyuuH1Wtyfod3sQmeqjOasemMV+03bK4/IyWGgNrZfQ=; b=PAWpI523ikOpqESy1MKnatVlRsf7jETQ4a3xuknoEonMYzqRjbbMfgWE3sVnIaAvptp08L /bo94Vcgznp7khYPWwUemjPIAcfOYva1nDWtICdnnn/SbcmrDHRaCyvogM87om98rAAhbS hMuGz6cIRXYOzmkFDUcYYyLXMcBJdHE= Received: from mx-prod-mc-04.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-106-z4bOYVHsNB2mtiR9Wm03Uw-1; Wed, 05 Mar 2025 05:49:58 -0500 X-MC-Unique: z4bOYVHsNB2mtiR9Wm03Uw-1 X-Mimecast-MFC-AGG-ID: z4bOYVHsNB2mtiR9Wm03Uw_1741171796 Received: from mx-prod-int-04.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-04.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.40]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-04.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 57A8D1955DCD; Wed, 5 Mar 2025 10:49:55 +0000 (UTC) Received: from vschneid-thinkpadt14sgen2i.remote.csb (unknown [10.44.32.95]) by mx-prod-int-04.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id CAE451954B32; Wed, 5 Mar 2025 10:49:48 +0000 (UTC) From: Valentin Schneider To: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-rt-users@vger.kernel.org Cc: Catalin Marinas , Will Deacon , Mike Galbraith , Peter Collingbourne , Mark Rutland , Thomas Gleixner , Neeraj Upadhyay , Thiago Jung Bauermann , Mark Brown , Kristina Martsenko , Sebastian Andrzej Siewior , Petr Tesarik , Jinjie Ruan , Juri Lelli , Phil Auld Subject: [PATCH 0/1] arm64: enable PREEMPT_LAZY Date: Wed, 5 Mar 2025 11:49:24 +0100 Message-ID: <20250305104925.189198-1-vschneid@redhat.com> Precedence: bulk X-Mailing-List: linux-rt-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.0 on 10.30.177.40 Hey folks, This is a resubmission of Mark's patch [1]. I didn't end up changing anything other than fluffing up the changelog. I ran this under an arm64 VM, added some trace_printk's and checked that sched_switch's between runnable hackbench threads would occurr in the right conditions: o with TIF_NEED_RESCHED_LAZY set o at the tick o at do_notify_resume() o with TIF_NEED_RESCHED set [1]: https://lore.kernel.org/linux-rt-users/Z2B5y3HiLuRHPfdv@J2N7QTR9R3.cambridge.arm.com/ Cheers, Valentin Mark Rutland (1): arm64: enable PREEMPT_LAZY arch/arm64/Kconfig | 1 + arch/arm64/include/asm/thread_info.h | 16 +++++++++------- arch/arm64/kernel/entry-common.c | 2 +- 3 files changed, 11 insertions(+), 8 deletions(-) Acked-by: Mark Rutland --- 2.43.0