From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 259CA15AD3 for ; Wed, 20 Sep 2023 12:37:46 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A112BC433C9; Wed, 20 Sep 2023 12:37:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1695213466; bh=5TJk3nsrvYx/dI934kKu+QBoEttnuiPGUvIKP/oHGTg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=No6Wt4rOuXzFHOutmXQC73VR38wmWFCptKslq5/VNIkY3ZXGHIJirALcpEgdWc+qC jZQCyG2u3l+NnrFP/jBa33p2QcLzNXf3mNk3blxGcqDytwgtmlz+tVuxa216r6iAIB p1Tb7r9yL8owaSgWTT9CzXsS1YO+oZS5XGV542Zo= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Helge Deller Subject: [PATCH 5.4 248/367] parisc: led: Reduce CPU overhead for disk & lan LED computation Date: Wed, 20 Sep 2023 13:30:25 +0200 Message-ID: <20230920112904.972862261@linuxfoundation.org> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20230920112858.471730572@linuxfoundation.org> References: <20230920112858.471730572@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Helge Deller commit 358ad816e52d4253b38c2f312e6b1cbd89e0dbf7 upstream. Older PA-RISC machines have LEDs which show the disk- and LAN-activity. The computation is done in software and takes quite some time, e.g. on a J6500 this may take up to 60% time of one CPU if the machine is loaded via network traffic. Since most people don't care about the LEDs, start with LEDs disabled and just show a CPU heartbeat LED. The disk and LAN LEDs can be turned on manually via /proc/pdc/led. Signed-off-by: Helge Deller Cc: Signed-off-by: Greg Kroah-Hartman --- drivers/parisc/led.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/parisc/led.c +++ b/drivers/parisc/led.c @@ -56,8 +56,8 @@ static int led_type __read_mostly = -1; static unsigned char lastleds; /* LED state from most recent update */ static unsigned int led_heartbeat __read_mostly = 1; -static unsigned int led_diskio __read_mostly = 1; -static unsigned int led_lanrxtx __read_mostly = 1; +static unsigned int led_diskio __read_mostly; +static unsigned int led_lanrxtx __read_mostly; static char lcd_text[32] __read_mostly; static char lcd_text_default[32] __read_mostly; static int lcd_no_led_support __read_mostly = 0; /* KittyHawk doesn't support LED on its LCD */