From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) (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 BB23F207217 for ; Fri, 11 Oct 2024 07:36:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.142.43.55 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728632173; cv=none; b=asaZ8MaD2K0PsbO1VIrlZh0VZFKosb9FjC/xOhUaaWW0PhvhPHyK9HZI7T8LkCSuv+CU7ccvqNVZxc+CPc8qvW2cdHPXgyBs1UpbJPgdn1vBPpW6v4f8R4MT1AbccARM9y7xOLRcUGPbQGNYsc39mFDu/8DLORaDFgJrcus8RGs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728632173; c=relaxed/simple; bh=whySh61HgodXvQh0vqNlizeOAQpNCi7xdB+X+d9zW94=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=e0iLu9jGzhiBJwmfoH0EBErpJkvpBRQvWwfk+fJt2kbrgV4vtVQI7scGQVXIwSxhVR8jhWQI/M80dYCCmKH5kntKb14PEMC1rsLrK37C0hV5Aw8UqRl2VBgSY7Dy/nfAjRfGYm5oT35fLNVxHVtxEZ7rwNcTkA6uwKCchWgHjvI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de; spf=pass smtp.mailfrom=linutronix.de; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=tb1XGb7Y; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=895jXCVn; arc=none smtp.client-ip=193.142.43.55 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linutronix.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="tb1XGb7Y"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="895jXCVn" Date: Fri, 11 Oct 2024 09:36:02 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1728632164; 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: in-reply-to:in-reply-to:references:references; bh=7dvx7jsEginLAx6CoxNWrWaKXiC/f26aLcG1G/Nbr40=; b=tb1XGb7Yi9n0Ry7kcXqpa5BDrImWMdTpr3nK7kPp7b0vW1mqiCWzwW9jCuL7ldSAnA70Vx 0MtyYYyDn/cjOk7I8hMpFMqqnSQwNLgbvK5pNVU0zIGAIBxO37KgNyrAVmoxhafmmJ0VpD l3COggzjTidA6R2YxEozZiOneYzuCrdzSBscNDPvl/dqPfNFFaIu6V9kE+QyoMyvSXyra7 z6gwHUoGpXru97V9Uz8I/qWN+L+Kyo67wHqHE6Sm8FsTZ/Oix3+T8lEEppH6rsP6Og1/17 bLSzp1VIvfbBnO+IeRs+T1xXUA+rXZApa7W9lgefxGwcJE25G8y67k0s5FpmKA== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1728632164; 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: in-reply-to:in-reply-to:references:references; bh=7dvx7jsEginLAx6CoxNWrWaKXiC/f26aLcG1G/Nbr40=; b=895jXCVngb/SiyPVyuip6AEXM53goYxo61mTj8iuhnMPKGst6XuZ8VKSIurOeOTp1EPKzB RtCVzv2XUfTF05Dw== From: Sebastian Andrzej Siewior To: Ankur Arora Cc: linux-kernel@vger.kernel.org, peterz@infradead.org, tglx@linutronix.de, paulmck@kernel.org, mingo@kernel.org, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, vschneid@redhat.com, frederic@kernel.org, efault@gmx.de Subject: Re: [PATCH 6/7] osnoise: handle quiescent states for PREEMPT_RCU=n, PREEMPTION=y Message-ID: <20241011073602.7EmDWFkc@linutronix.de> References: <20241009165411.3426937-1-ankur.a.arora@oracle.com> <20241009165411.3426937-7-ankur.a.arora@oracle.com> <20241010065338.sw4zZlbm@linutronix.de> <87plo797a2.fsf@oracle.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=utf-8 Content-Disposition: inline In-Reply-To: <87plo797a2.fsf@oracle.com> On 2024-10-10 10:50:29 [-0700], Ankur Arora wrote: > > PREEMPTION=y, PREEMPT_RCU=n should not be possible. > > That's a statement. Is there an argument here? For my taste you should describe in your cover letter the actual problem and what you intend to do about it. Then you should a series addressing this issue which would probably qualify for all patches in your series but 7/7 (the PPC bits for lazy preempt). 7/7 should have been the part where you make possible to make PREEMPT_RCU selectable. Based on my understanding so far you (or Paul) want to make PREEMPT_RCU selectable if PREEMPT_LAZY is enabled _or_ if DYNAMIC_PREEMPT is enabled with the NONE or VOLUNTARY model. This series as-is made no sense to me until Peter made the snippet where you could indeed make PREEMPT_RCU selectable. Sebastian