From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=209.85.210.42 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1792759737; b=TB8BuSM1uoGq9ELAwqnZx2Kgnsk5g2Du02IfU/crtkaF5SxvcrROivK/ezsM3q2zgWMH b10ndcVSd14ubiWoxu1JbqciuIEEfA/hoonwDdpUHrxiUzWqNAqOs3NBtu/qwRNjrecXJ 3WFKzA67AMRa5iuUlrA6Wvb18wa8hCsWNvd6IiIbSxMmUOY1hGfx/sawdOXa3MCwyufOL maKI0TG//2Vs33DjC88sRYK3FBH1ynj6pE6+nOfV657xZImHJ3mAB+oaFTZPjoIFgI8LL WmaCfI8QdttZ7/LVunwfRFcx6p1blofv6BDRpxONs12x+rur+oXcZX6mbtOq+CryCjw== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1792759737; h=DMARC-Filter:Received:DKIM-Signature:X-Google-DKIM-Signature: X-Forwarded-Encrypted:X-Gm-Message-State:X-Gm-Gg:X-Received:Received: Message-ID:Date:MIME-Version:User-Agent:Subject:To:Cc:References: Content-Language:From:In-Reply-To:Content-Type: Content-Transfer-Encoding; bh=AauMIhJF1QGD9945xyHgO/hlfJd5Li+gb8s1bXigGyc=; b=XoHkX8MBoKNdWjQN6LLiXsnq0EXOhb5GDc0WXuiR4wC34pbxFVwRtgU3mlyjLcGbHQoC T74m8ZxJnAdxeApZZ4E7suDWsVP/zZvJlDiKIkBqMC8Oh5FdCik5lrZkOsnvzQ/6b9YBz Q+LUliB8VehLao3k6zfT7vN3aS5+aqkJdr3Ye926YhNbyTbsmZFnzmJ9bVI0weh1KxJjn vDrLrweuIy1TFmMwh/2+cA2CEPpkjlbUsM08qcS4eQtLCducO/Rg0liMytpQksZ3wZ7TO ulfYiunYkfYk1X7xiVsY6FmvNQOGfVk6uZ6PF40UDkSIP8nr/L4jkXTSsw/ytYJBBGg== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=riscstar.com; spf=pass smtp.mailfrom=riscstar.com; dkim=pass header.d=riscstar-com.20251104.gappssmtp.com header.i=@riscstar-com.20251104.gappssmtp.com header.a=rsa-sha256 header.s=20251104 header.b=XF9u4sox; arc=none smtp.remote-ip=209.85.210.42 Received: from mail-ot1-f42.google.com (mail-ot1-f42.google.com [209.85.210.42]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3D359606A31B for ; Fri, 23 Oct 2026 12:48:57 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 3D359606A31B Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=riscstar.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=riscstar.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=riscstar-com.20251104.gappssmtp.com header.i=@riscstar-com.20251104.gappssmtp.com header.a=rsa-sha256 header.s=20251104 header.b=XF9u4sox Received: by mail-ot1-f42.google.com with SMTP id 46e09a7af769-7f432ac553fso777091a34.3 for ; Fri, 23 Oct 2026 05:48:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=riscstar-com.20251104.gappssmtp.com; s=20251104; t=1792759736; x=1793364536; darn=vger.kernel.org; h=content-transfer-encoding:content-type:in-reply-to:from :content-language:references:cc:to:subject:user-agent:mime-version :date:message-id:from:to:cc:subject:date:message-id:reply-to :content-type; bh=AauMIhJF1QGD9945xyHgO/hlfJd5Li+gb8s1bXigGyc=; b=XF9u4soxGXFA0RQCyd++WhRmRj/0BJiMXQEhBhgD48Q45N9CLU6LSHl0hd9lX2Qs9l pZ7kYEm+htyFqJM0gFg7bjrVJszrcwcW8ev06Hogn6LmZ4uC5x5gF0Tb33JvTcw0HOLz gl8KalXbUYpN1ENER8lSQXL7OaEMCTnILuW+4z0Vk2Kj+SVEpuA3zSV+muYjVYwqORtb a5Mf/4R7q+mVzcb1x6ftmTzttUWuhyfso34h3geMNOYuzxWHL7o0McBcyBeLmJDbtJ6k 6sJz7lfO2SYFq4P2EW1CTGDQAjiGNHj1HbFPZQG59MkDkCMROXZseuIHrlgIezZVjSUm OhzA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1792759736; x=1793364536; h=content-transfer-encoding:content-type:in-reply-to:from :content-language:references:cc:to:subject:user-agent:mime-version :date:message-id:x-gm-gg:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to:content-type; bh=AauMIhJF1QGD9945xyHgO/hlfJd5Li+gb8s1bXigGyc=; b=aXBGOrQ0q54wFk+/S0VzOsP+YNy/m6s+AbcEPxL4oVZh4ZiqLi9iRULnQ5wVmWGeXy lbv1t5aRf2/ysVObzaF6o8WJM3DeDLg3B687ZwOCw9z2DRwcmnauTtUM5QRoRUSuXJHE SUhulgHQAqH1sdiXAAU8UcCzRMteSMpykj6yUSaHKvVKKwAl0hO40GhuI+eB6qvR1O7T 4BfyBv+dMbBuEIFkIaYMT8hyxVQPr9bk+mAxQjKvXctyURy0H7em2OB6B2ZqchQO/zfD BgeyOQtx/FHXbiFH/sZjOG2p6Mb8pfeukarYJjbXSurkc5S35vbGqM1I5oLJKjoBHDBj IeZA== X-Forwarded-Encrypted: i=1; AKwUvBwUfMg93MShrmTWrBmyQeh+5H4EZ9wIEZiRHJ5b2NLUFOxHsBQ81ZB6YpO6I5wrm0G0uiiQbOXqrTCJO3U=@vger.kernel.org X-Gm-Message-State: AFq9FYK8P7m7kf+zbpgz/E5c7fSHOc7BS9nTMfuik/PWw2UE4ioK79dQ kh8lKLPM+YyPGcoqRGX+hI0gdM4qZI4JDbmC8V3MWLJoVNFB/PzvPSmj52Mc3A6Nx5s= X-Gm-Gg: AYBFou1ADZO7NqIory3fxOGKHXFWuirnXw5ATqLT//iSuJN/uxveDse1ZPnh/aASjwk NQ9p6mTG/Ch+x3z/n43Mhzyqkkwphuw0ClVdNSKXVXuJ3XaB6oWyhGGf5xL5nLI3ugRDzwlfp7Z TTSzDAof6XXxPiZFTKbTwHKl8Piusn8V2xSvrdDuaI5U3dVOpJ/xgWQJpZjlH3okzEINZMFsv6P yfVdIcfJLSquMhU8iedvLIyWKWpPrvWPYHq6nWGmSDUChy3jQwe2TdoCH5TFeaE1A0zesb2+GSI IO9ifaP0WiVT6Loj1+JEvsQ5t1au0WZFZoQBu41ZqVP0+E8omfdEkH+4QQrYaQBz/WVQP/vTP0Q 45zO3U3mW16X+LwWURTJBBzqq57ioh04pmSEvrACkY3WnmWTpq17A0f5qxo5gb9XRI3jC/1+LHS OAOkSXws6jWYaYEFcS6FgmrZFkGADIOmi7fdcDAp+Ab1vSfvbVXU7RwN2a7UM/NNJkEwyngNq1P X90Omo3EugCg4kfTIbHifye4usJnIEL/rCjOJTAAwz0ZEc+YyuwB177VYEKMkPALsZzSdqJxQyW U38= X-Received: by 2002:a05:6830:264a:b0:819:1804:d208 with SMTP id 46e09a7af769-84fb2906f38mr1294739a34.13.1792759736186; Fri, 23 Oct 2026 05:48:56 -0700 (PDT) Received: from [172.22.22.28] ([73.62.185.64]) by smtp.gmail.com with ESMTPSA id 46e09a7af769-84fbe66cab7sm1910704a34.23.2026.10.23.05.48.55 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 23 Oct 2026 05:48:55 -0700 (PDT) Message-ID: Date: Fri, 23 Oct 2026 07:48:54 -0500 X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2] staging: greybus: loopback: Use fsleep() for delay To: pavankumaryalagada@gmail.com, greybus-dev@lists.linaro.org, outreachy@lists.linux.dev Cc: pure.logic@nexus-software.ie, johan@kernel.org, elder@kernel.org, gregkh@linuxfoundation.org, linux-staging@lists.linux.dev, linux-kernel@vger.kernel.org References: <20261022202455.104142-1-pavankumaryalagada@gmail.com> Content-Language: en-US From: Alex Elder In-Reply-To: <20261022202455.104142-1-pavankumaryalagada@gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 10/22/26 3:24 PM, pavankumaryalagada@gmail.com wrote: > From: Yalagada Pavan Kumar > > In the loopback function, usleep_range() is used for short delays > and msleep() for longer delays. This requires choosing the delay > function based on the requested time and converting microseconds > to milliseconds when using msleep(). > > Replace both functions with fsleep(), which chooses a delay > delay method based on the requested time. For short delays, s/delay delay/delay/ I think "checkpatch.pl" would have caught this. Maybe Greg can fix this up. > fsleep() allows up to 25% extra time instead of the fixed 100 > microseconds. For longer delays, the old code rounds the > requested time down to whole milliseconds, while fsleep() rounds > it up when using msleep(). > > These changes may affect time between loopback operations and > the reported performance. > > Suggested-by: Alex Elder > Signed-off-by: Yalagada Pavan Kumar Looks good to me. Nice job. Reviewed-by: Alex Elder > --- > v2: > - Add more details about how fsleep() affects delays. > - Update the subject to include the loopback module. > > v1: https://lore.kernel.org/outreachy/c482704b-903e-413d-ba7b-5bf31c0a6104@riscstar.com/T/#t > --- > drivers/staging/greybus/loopback.c | 8 ++------ > 1 file changed, 2 insertions(+), 6 deletions(-) > > diff --git a/drivers/staging/greybus/loopback.c b/drivers/staging/greybus/loopback.c > index efc69c10cffe..2fe845eaef29 100644 > --- a/drivers/staging/greybus/loopback.c > +++ b/drivers/staging/greybus/loopback.c > @@ -898,12 +898,8 @@ static int gb_loopback_fn(void *data) > gb->send_count++; > mutex_unlock(&gb->mutex); > > - if (us_wait) { > - if (us_wait < 20000) > - usleep_range(us_wait, us_wait + 100); > - else > - msleep(us_wait / 1000); > - } > + if (us_wait) > + fsleep(us_wait); > } > > gb_pm_runtime_put_autosuspend(bundle);