From patchwork Fri Jan 10 12:53:57 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Rafael J. Wysocki" X-Patchwork-Id: 856450 Received: from cloudserver094114.home.pl (cloudserver094114.home.pl [79.96.170.134]) (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 3FB8C20DD53; Fri, 10 Jan 2025 12:57:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=79.96.170.134 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736513882; cv=none; b=ZU4s889mjLqPjq974OAIECzgZiP4YE5jNIMJejT3ciFYzfZEfYIichWSSU0XGLgVQsn5kRJV0YeUKMdmE/JXFqZAf+2Rlex22bVa0W0nPx1fR3yeiPOVZ7hGPtfeHAuogrhMDENVccA+E/TKVy9tDV+nFnvmxFzG8W2Q9r/drPw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736513882; c=relaxed/simple; bh=LVbRvsshn0Bs3rOsCebMtDGzdAIaFrarmaICvHLvZXY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=YWkcuHCGORtxCDpCPFKRe8dWb/NsOjxrXR6vWv2x9qPa9aPUdPFm43XAgORTxu01aHjoK5k1Gzir9IxIqaBWNoyhG9AccyQmPfzdVH4zJJp64vvw8k9x/J3fZD+qgtAuXimn+xgUnx8+tgjyaji/jlynM4rTspDqCNHEqWmfj6I= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=rjwysocki.net; spf=pass smtp.mailfrom=rjwysocki.net; dkim=pass (2048-bit key) header.d=rjwysocki.net header.i=@rjwysocki.net header.b=qeuxRRoi; arc=none smtp.client-ip=79.96.170.134 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=rjwysocki.net Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=rjwysocki.net Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=rjwysocki.net header.i=@rjwysocki.net header.b="qeuxRRoi" Received: from localhost (127.0.0.1) (HELO v370.home.net.pl) by /usr/run/smtp (/usr/run/postfix/private/idea_relay_lmtp) via UNIX with SMTP (IdeaSmtpServer 6.2.1) id c174eccfaff98ff8; Fri, 10 Jan 2025 13:57:58 +0100 Received: from kreacher.localnet (unknown [195.136.19.94]) (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 cloudserver094114.home.pl (Postfix) with ESMTPSA id C9E218E05BD; Fri, 10 Jan 2025 13:57:57 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=rjwysocki.net; s=dkim; t=1736513878; bh=LVbRvsshn0Bs3rOsCebMtDGzdAIaFrarmaICvHLvZXY=; h=From:Subject:Date; b=qeuxRRoimgov9x5B42OBeP6un08ahbecTIPd8XlU8VVz7M/mHOKh7lVLOGLSddkJz X7J1TGDDDSu3dAwZmWoCQeUDauowx1ZtuLWxuKDuX3IIPPSgWeN93hn9BgMfPfBtl0 wPC/yzVY75BSFVCqwhqMjnKDYdD9hCkkdb375PWmhsnxjoPSlHzs9eSZU/HJLMizD+ fqG2mtEGK2H+obOBVC2masyq0R/2xekZPCbmg3Yov5RFNOzyWBCn2ARn2/nsZQlwYy 1sDehnISXsjbYygslTEjxQC40eVYG/E2GxRpSBUyrL3PsGMOA4fo/BT7zIdf+o/kdv empTo5Wq6bvqw== From: "Rafael J. Wysocki" To: Linux PM Cc: LKML , Daniel Lezcano , Christian Loehle , Artem Bityutskiy Subject: [PATCH v1 1/4] cpuidle: teo: Add polling flag check to early return path Date: Fri, 10 Jan 2025 13:53:57 +0100 Message-ID: <13679187.uLZWGnKmhe@rjwysocki.net> In-Reply-To: <4953183.GXAFRqVoOG@rjwysocki.net> References: <4953183.GXAFRqVoOG@rjwysocki.net> Precedence: bulk X-Mailing-List: linux-pm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-CLIENT-IP: 195.136.19.94 X-CLIENT-HOSTNAME: 195.136.19.94 X-VADE-SPAMSTATE: clean X-VADE-SPAMCAUSE: gggruggvucftvghtrhhoucdtuddrgeefuddrudegkedggeeiucetufdoteggodetrfdotffvucfrrhhofhhilhgvmecujffqoffgrffnpdggtffipffknecuuegrihhlohhuthemucduhedtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmdenucfjughrpefhvfevufffkfgjfhgggfgtsehtufertddttdejnecuhfhrohhmpedftfgrfhgrvghlucflrdcuhgihshhotghkihdfuceorhhjfiesrhhjfiihshhotghkihdrnhgvtheqnecuggftrfgrthhtvghrnhepvdffueeitdfgvddtudegueejtdffteetgeefkeffvdeftddttdeuhfegfedvjefhnecukfhppeduleehrddufeeirdduledrleegnecuvehluhhsthgvrhfuihiivgeptdenucfrrghrrghmpehinhgvthepudelhedrudefiedrudelrdelgedphhgvlhhopehkrhgvrggthhgvrhdrlhhotggrlhhnvghtpdhmrghilhhfrhhomheprhhjfiesrhhjfiihshhotghkihdrnhgvthdpnhgspghrtghpthhtohephedprhgtphhtthhopehlihhnuhigqdhpmhesvhhgvghrrdhkvghrnhgvlhdrohhrghdprhgtphhtthhopehlihhnuhigqdhkvghrnhgvlhesvhhgvghrrdhkvghrnhgvlhdrohhrghdprhgtphhtthhopegurghnihgvlhdrlhgviigtrghnoheslhhinhgrrhhordhorhhgpdhrtghpthhtoheptghhrhhishhtihgrnhdrlhhovghhlhgvsegrrhhmrdgtohhmpdhrtghpthhtoheprghrthgvmhdrsghithihuhhtshhkihihsehlihh X-DCC--Metrics: v370.home.net.pl 1024; Body=5 Fuz1=5 Fuz2=5 From: Rafael J. Wysocki After commit 6da8f9ba5a87 ("cpuidle: teo: Skip tick_nohz_get_sleep_length() call in some cases") the teo governor behaves a bit differently on systems where idle state 0 is a "polling" state (that is, it is not really an idle state, but a loop continuously executed by the CPU). Namely, on such systems it skips the tick_nohz_get_sleep_length() call if the target residency of the current candidate idle state is small enough. However, if state 0 itself was to be returned, it would be returned right away without calling tick_nohz_get_sleep_length() even on systems where it was not a "polling" state until commit 4b20b07ce72f ("cpuidle: teo: Don't count non-existent intercepts") that attempted to fix this problem. Unfortunately, commit 4b20b07ce72f has made the governor always call tick_nohz_get_sleep_length() when about to return state 0 early, even if that state is a "polling" one, which is inconsistent and defeats the purpose of commit 6da8f9ba5a87 in that case. Address this by adding a CPUIDLE_FLAG_POLLING check to the path where state 0 is returned early to prevent tick_nohz_get_sleep_length() from being called if it is a "polling" state. Fixes: 4b20b07ce72f ("cpuidle: teo: Don't count non-existent intercepts") Signed-off-by: Rafael J. Wysocki --- drivers/cpuidle/governors/teo.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/cpuidle/governors/teo.c +++ b/drivers/cpuidle/governors/teo.c @@ -422,7 +422,8 @@ first_suitable_idx = i; } } - if (!idx && prev_intercept_idx) { + if (!idx && prev_intercept_idx && + !(drv->states[0].flags & CPUIDLE_FLAG_POLLING)) { /* * We have to query the sleep length here otherwise we don't * know after wakeup if our guess was correct. From patchwork Fri Jan 10 12:55:29 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Rafael J. Wysocki" X-Patchwork-Id: 856451 Received: from cloudserver094114.home.pl (cloudserver094114.home.pl [79.96.170.134]) (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 6B2EE20A5E9; Fri, 10 Jan 2025 12:57:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=79.96.170.134 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736513880; cv=none; b=qnh7CUSFws/Ju3CUyf7GXddK+0OpLl/D7ZeV6X30LnjzHseRhQ+XZ3ARkwmRabmd4/q/lyq0SuhIcfZAXVYLoG2SwcELVsz0YY8M3q/AN3tb6zWIyCB4XGhDDnKJKtFRUkISuqSclwRFeFzpk7VeofdO0AuvIjUOA9m9sHSvJbo= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736513880; c=relaxed/simple; bh=JwT38iZan3te1sUrNeDmcKgV3zvQtH2PT7sDx6rv1bM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=C5iQMkcEY3VxdNF7cIVcI9kZS8mrznA36GIcfjSeaJpfemxh89rbR24pHaZHjNxWM7xKcLmqF+rOb9oTm1UL/ZSgBPBB+98/2Tnu5Nm1IxUmKWyGnv1lN1cIaKwgnf26C2H/GtypkK0A3XL3Cua1ejVsXnf/LMrNXTTAoeBkOE4= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=rjwysocki.net; spf=pass smtp.mailfrom=rjwysocki.net; dkim=pass (2048-bit key) header.d=rjwysocki.net header.i=@rjwysocki.net header.b=Cv2PqwJ/; arc=none smtp.client-ip=79.96.170.134 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=rjwysocki.net Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=rjwysocki.net Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=rjwysocki.net header.i=@rjwysocki.net header.b="Cv2PqwJ/" Received: from localhost (127.0.0.1) (HELO v370.home.net.pl) by /usr/run/smtp (/usr/run/postfix/private/idea_relay_lmtp) via UNIX with SMTP (IdeaSmtpServer 6.2.1) id faff95d8c2ca581f; Fri, 10 Jan 2025 13:57:56 +0100 Received: from kreacher.localnet (unknown [195.136.19.94]) (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 cloudserver094114.home.pl (Postfix) with ESMTPSA id D69BD8E05BD; Fri, 10 Jan 2025 13:57:55 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=rjwysocki.net; s=dkim; t=1736513876; bh=JwT38iZan3te1sUrNeDmcKgV3zvQtH2PT7sDx6rv1bM=; h=From:Subject:Date; b=Cv2PqwJ/sANhOJtTpO9Vk9qRQJPxJAwVeXr2Q5GMsXqGCS+Vq4ps5kRE7ScjP+mrB pkiwdNNHIFIMmOfwaSqBvI0DjBFuS52KaH8yLcT6/bfMdtkuyDiMCvxGamhYmzVhik kgP0BVq+rj04arc9I2THVdC9BrnN4AleX63FAFn+owtn6hIE7R8Qi8jcHqinW7lfJB 7gVQOzwDH3Z++Q5EpvwnGanXG1x6Bgk9z2AASDvd17Kbs9LrLYE6Ipj01biAfeBNBE sD0ipYmEypRyW7yJeiTQ0nbCThnpPsKDKWLwyKkcwmtlIj3JMrK1lvDrNjiihLMIZt W02UV//X6tsow== From: "Rafael J. Wysocki" To: Linux PM Cc: LKML , Daniel Lezcano , Christian Loehle , Artem Bityutskiy Subject: [PATCH v1 3/4] cpuidle: teo: Reorder candidate state index checks Date: Fri, 10 Jan 2025 13:55:29 +0100 Message-ID: <8476650.T7Z3S40VBb@rjwysocki.net> In-Reply-To: <4953183.GXAFRqVoOG@rjwysocki.net> References: <4953183.GXAFRqVoOG@rjwysocki.net> Precedence: bulk X-Mailing-List: linux-pm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-CLIENT-IP: 195.136.19.94 X-CLIENT-HOSTNAME: 195.136.19.94 X-VADE-SPAMSTATE: clean X-VADE-SPAMCAUSE: gggruggvucftvghtrhhoucdtuddrgeefuddrudegkedggeeiucetufdoteggodetrfdotffvucfrrhhofhhilhgvmecujffqoffgrffnpdggtffipffknecuuegrihhlohhuthemucduhedtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmdenucfjughrpefhvfevufffkfgjfhgggfgtsehtufertddttdejnecuhfhrohhmpedftfgrfhgrvghlucflrdcuhgihshhotghkihdfuceorhhjfiesrhhjfiihshhotghkihdrnhgvtheqnecuggftrfgrthhtvghrnhepvdffueeitdfgvddtudegueejtdffteetgeefkeffvdeftddttdeuhfegfedvjefhnecukfhppeduleehrddufeeirdduledrleegnecuvehluhhsthgvrhfuihiivgeptdenucfrrghrrghmpehinhgvthepudelhedrudefiedrudelrdelgedphhgvlhhopehkrhgvrggthhgvrhdrlhhotggrlhhnvghtpdhmrghilhhfrhhomheprhhjfiesrhhjfiihshhotghkihdrnhgvthdpnhgspghrtghpthhtohephedprhgtphhtthhopehlihhnuhigqdhpmhesvhhgvghrrdhkvghrnhgvlhdrohhrghdprhgtphhtthhopehlihhnuhigqdhkvghrnhgvlhesvhhgvghrrdhkvghrnhgvlhdrohhrghdprhgtphhtthhopegurghnihgvlhdrlhgviigtrghnoheslhhinhgrrhhordhorhhgpdhrtghpthhtoheptghhrhhishhtihgrnhdrlhhovghhlhgvsegrrhhmrdgtohhmpdhrtghpthhtoheprghrthgvmhdrsghithihuhhtshhkihihsehlihh X-DCC--Metrics: v370.home.net.pl 1024; Body=5 Fuz1=5 Fuz2=5 From: Rafael J. Wysocki Since constraint_idx may be 0, the candidate state index may change to 0 after assinging constraint_idx to it, so first check if it is greater than constraint_idx (and update it if so) and then check it against 0. Signed-off-by: Rafael J. Wysocki --- drivers/cpuidle/governors/teo.c | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-) --- a/drivers/cpuidle/governors/teo.c +++ b/drivers/cpuidle/governors/teo.c @@ -428,6 +428,14 @@ break; } } + + /* + * If there is a latency constraint, it may be necessary to select an + * idle state shallower than the current candidate one. + */ + if (idx > constraint_idx) + idx = constraint_idx; + if (!idx && prev_intercept_idx && !(drv->states[0].flags & CPUIDLE_FLAG_POLLING)) { /* @@ -440,13 +448,6 @@ } /* - * If there is a latency constraint, it may be necessary to select an - * idle state shallower than the current candidate one. - */ - if (idx > constraint_idx) - idx = constraint_idx; - - /* * Skip the timers check if state 0 is the current candidate one, * because an immediate non-timer wakeup is expected in that case. */