From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.forwardemail.net (smtp.forwardemail.net [149.28.215.223]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9EBAE3E51E8 for ; Mon, 6 Jul 2026 23:23:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=149.28.215.223 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783380213; cv=none; b=VSbs1qagQ2Idzk1BleE3+Uw2tVaQ5kIjeuPKR2PLPtLLUdq3wDcTeG2XQpAM1kUPTNxPQEly81CrkpWeQV8Wi3CyejtrYC+Y46eZkGwwE70n5dPNB+Mk+Au/53wsbMjx9UNhS9UYB5R6LcwohDLQt/bQNcR+tcXzpwc9SKNG8K4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783380213; c=relaxed/simple; bh=rWWebR3w8Mim8nqyrpPGlBB+sWkzlr8vPrDMP4Qn8+8=; h=Mime-Version:Content-Type:Date:Message-Id:Subject:From:To:Cc: References:In-Reply-To; b=hM5tdu+99y8XbV33xuDsIL25ls07Y3zMPuUKhPMEdAmCah33fHR6dhFd+ceuPqvl4ZxALlg44vVbgn15igjPOft7o0MGeUGNEHmU9V+5V4ZjmgW4eLahSIIgwZpqvEb8eCPJl2rd/1Lirqu8be/fUorIAwxfgD2COadigO4NzUQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=ubuntu.com; spf=pass smtp.mailfrom=fe-bounces.ubuntu.com; dkim=pass (2048-bit key) header.d=ubuntu.com header.i=@ubuntu.com header.b=Jl+uKqXM; arc=none smtp.client-ip=149.28.215.223 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=ubuntu.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=fe-bounces.ubuntu.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=ubuntu.com header.i=@ubuntu.com header.b="Jl+uKqXM" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ubuntu.com; h=In-Reply-To: References: Cc: To: From: Subject: Message-Id: Date: Content-Type: Content-Transfer-Encoding: Mime-Version; q=dns/txt; s=fe-953a8a3ca9; t=1783380210; bh=OEZrGANo2cEZWsDxSQlyGeYA6D2OMj2sQBUWO+CdYtI=; b=Jl+uKqXMLyKo/uN3yCDo9ku4BLb55S0RLaEdNj20VOZaKs8GrWkMERcyQo/uoZg+NzvxxGyNy iQI+1uz27iUdSgCChGLgROWzu+jhG8Zu2R5DnWHO71KDIPNqWapMOWtm5LmQlPA93+m16HgNY+W 6ebv5Low9D0jwsnJDp52XGeXV+lVfwUelKSC5/Vb5B4oi8fAcBmTg0aq+ng6ATWspfHDw1XyvMj /I0pvEH7wZJSVC3XUDIKtiCmmumomtdfXa52X8W+mlAdd0pgXSUP853mDuw8zq/Mj5NvFUxCSnw pEPUyJlSh2hFRStCJ9lSJ3j/+otoKmtOyHDq0Sy45HsA== X-Forward-Email-ID: 6a4c3867ebac8711c86b79d5 X-Forward-Email-Sender: rfc822; jpeisach@ubuntu.com, smtp.forwardemail.net, 149.28.215.223 X-Forward-Email-Version: 2.9.7 X-Forward-Email-Website: https://forwardemail.net X-Complaints-To: abuse@forwardemail.net X-Report-Abuse: abuse@forwardemail.net X-Report-Abuse-To: abuse@forwardemail.net Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=UTF-8; format=Flowed Date: Mon, 06 Jul 2026 19:21:09 -0400 Message-Id: Subject: Re: [PATCH] arch: arm64: add early_param idle= From: "Joshua Peisach" To: "Yureka Lilian" , "Jonathan Corbet" , "Shuah Khan" , "Catalin Marinas" , "Will Deacon" Cc: , , , X-Mailer: aerc 0.21.0 References: <20260705-arm64-idle-param-v1-1-7454249f473f@cyberchaos.dev> In-Reply-To: <20260705-arm64-idle-param-v1-1-7454249f473f@cyberchaos.dev> On Sun Jul 5, 2026 at 6:02 AM EDT, Yureka Lilian wrote: > + > +enum idle_mode idle =3D WFI; > + > +/* User can over-ride above with "idle=3D" in cmdline */ > +static int __init setup_idle(char *s) > +{ > + if (!s) > + return -1; > + else if (!strcmp(s, "wfi")) > + idle =3D WFI; > + else if (!strcmp(s, "yield")) > + idle =3D YIELD; > + else if (!strcmp(s, "nop")) > + idle =3D NOP; > + else > + return -1; > + > + return 0; > +} > +early_param("idle", setup_idle); > + > /* > * cpu_do_idle() > * > @@ -26,8 +48,13 @@ void __cpuidle cpu_do_idle(void) > =20 > arm_cpuidle_save_irq_context(&context); > =20 > - dsb(sy); > - wfi(); > + if (likely(idle =3D=3D WFI)) { > + dsb(sy); > + wfi(); > + } else if (idle =3D=3D YIELD) { > + dsb(sy); > + asm volatile("yield" ::: "memory"); > + } > And otherwise...........? I guess it would be NOP, so do nothing - is this expected behavior? -Josh