From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="K+bFL8qf" Received: from mgamail.intel.com (mgamail.intel.com [192.55.52.43]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 314E2F5; Wed, 29 Nov 2023 01:01:53 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1701248512; x=1732784512; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=jUfEMJcGPk/pC7rsEa3j89yXra3uK2XLsI3C0myADGQ=; b=K+bFL8qfFmlKh1ttGEsFUEZAFiFY9d04DIw8qK6wpWJgus4rMeXk39zJ GqPPTawDDUPx/ocm8YUxOA7p0ue7x5k/Oc//IYEiuTSzHzn45VLCsGm85 vxZQvCTgBmrG8hD8GIMQP1ehZ7mYmQctXG9pCl5idyOiDxzGwEEy9KSrN uWzjrey9zrswmXIcRoqzkIoSUcjAN58OMowJjkCdLWkmbuPJp8gngsEEV P9Bi0ZI8ML0JRwRnnL48YGNViIkxM+goUq8H/DLh3vxpm8Gwuxs8C7sKh 3RNGxUnULO3y1MGcQHg7HjVrT5h5sRbxc1gtcl2WBD20Dw54bP+CvqLib Q==; X-IronPort-AV: E=McAfee;i="6600,9927,10908"; a="479328165" X-IronPort-AV: E=Sophos;i="6.04,235,1695711600"; d="scan'208";a="479328165" Received: from orsmga005.jf.intel.com ([10.7.209.41]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 Nov 2023 00:56:04 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10908"; a="942247871" X-IronPort-AV: E=Sophos;i="6.04,235,1695711600"; d="scan'208";a="942247871" Received: from black.fi.intel.com ([10.237.72.28]) by orsmga005.jf.intel.com with ESMTP; 29 Nov 2023 00:56:01 -0800 Received: by black.fi.intel.com (Postfix, from userid 1001) id 9036B23A; Wed, 29 Nov 2023 10:56:00 +0200 (EET) Date: Wed, 29 Nov 2023 10:56:00 +0200 From: Mika Westerberg To: "Rafael J. Wysocki" Cc: Linux ACPI , LKML , Zhang Rui , Srinivas Pandruvada , Michal Wilczynski , Hans de Goede , Andy Shevchenko , Heikki Krogerus , Mario Limonciello Subject: Re: [RFT][PATCH v1] ACPI: OSL: Use a threaded interrupt handler for SCI Message-ID: <20231129085600.GQ1074920@black.fi.intel.com> References: <5745568.DvuYhMxLoT@kreacher> Precedence: bulk X-Mailing-List: linux-acpi@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: <5745568.DvuYhMxLoT@kreacher> Hi Rafael, On Mon, Nov 27, 2023 at 08:57:43PM +0100, Rafael J. Wysocki wrote: > From: Rafael J. Wysocki > > In the current arrangement, all of the acpi_ev_sci_xrupt_handler() code > is run as an interrupt handler for the SCI, in interrupt context. Among > other things, this causes it to run with local interrupts off which > can be problematic if many GPEs are enabled and they are located in the > I/O address space, for example (because in that case local interrupts > will be off for the duration of all of the GPE hardware accesses carried > out while handling an SCI combined and that may be quite a bit of time > in extreme scenarios). > > However, there is no particular reason why the code in question really > needs to run in interrupt context and in particular, it has no specific > reason to run with local interrupts off. The only real requirement is > to prevent multiple instences of it from running in parallel with each > other, but that can be achieved regardless. > > For this reason, use request_threaded_irq() instead of request_irq() for > the ACPI SCI and pass IRQF_ONESHOT to it in flags to indicate that the > interrupt needs to be masked while its handling thread is running so as > to prevent it from re-triggering while it is being handled (and in > particular until the final handled/not handled outcome is determined). > > While at it, drop a redundant local variable from acpi_irq(). > > Signed-off-by: Rafael J. Wysocki > --- > > The code inspection and (necessarily limited) testing carried out by me > are good indications that this should just always work, but there may > be still some really odd platform configurations I'm overlooking, so if > you have a way to give it a go, please do so. Tried this on ADL-S and ADL-P systems that I have here and both work just fine with the patch applied. I can see SCI interrupt count increases in /proc/interrupts as expected. Did a couple of s2idle cycles too, all good. Tested-by: Mika Westerberg