From patchwork Wed Sep 11 13:29:45 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Anna-Maria Behnsen X-Patchwork-Id: 13800572 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) (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 DC76E1A3055; Wed, 11 Sep 2024 13:30:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.142.43.55 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726061410; cv=none; b=UziTl1uFJstbjKV6crLzasBlIGfxKMhdNUK1LU4rLuZYNStLVXy4XRTzfRTu8jttO0J3+g5puwIq0upMbQ1BGy20HWkkCNsKHqfkyKn6yEVudnlXI7aT1I8V/IDVM09iy2kvKbkr9GsGe5SHkfKyFYceiAFIlsx7jhQO12wmGc0= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726061410; c=relaxed/simple; bh=vA7knna/LPwJfgUOP3ICSdr+zzkqbT3SeaB70fpeZYg=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=OwKy7a4462I5F5tiqmFblrWKDj+UizrsWkpTL4uDeJt9rKIvpw+rrnLHw4F0WkWPJVb4aWYoa2Ut6Q+h6Qx4MevwsmCBm7zmXu2YHiRSXHa01uHvUlouoOW7fYC+S1TffZcuTxZ/nxyBi2JlJD9sUcSXrFgRDt5lyw1QOWq8xUk= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de; spf=pass smtp.mailfrom=linutronix.de; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=ERnRXz9t; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=Zf5BhUST; arc=none smtp.client-ip=193.142.43.55 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linutronix.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="ERnRXz9t"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="Zf5BhUST" From: Anna-Maria Behnsen DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1726061401; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=PA5NleTI3O9VX4sRx0U/XV0SMMtee51xgFSGfg7aJ7k=; b=ERnRXz9t6uXqimsAbceRTuGLpccpxh8saHvNsVM+/ZX59KDjwI8rTr6hVElM8ZiKzqc00f kQ1Qm6gmvFiX5g6vU0Pe6YkLX35VpBGyOQVTMMkTzj1HTTlXWr5djbFEKnc7hJMGbhW5hO n6SZHuHshYXYuh8skPHKFYQtbjr+lJ4Wq2TFVyi2YZF8qg6LSs7HxNA0ttEFO1g6o3CAgN Tt1cuPsZXH7lYkI/3NuCExVhN3wREoeho4bO32sBqOkcNKTXtqTgzcKr2mxXR1V2DKUkTd 8zA59sslR4rLZJTTTdPSgXOseX7boo1hMH9vhnPCz3+THAsHcngAjGjTP7H21g== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1726061401; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=PA5NleTI3O9VX4sRx0U/XV0SMMtee51xgFSGfg7aJ7k=; b=Zf5BhUSTJDSV0Do7rSkYhzvp/cA0MeEBykr3ustNj0XHvaanM0t77Wh3eJu04r9e+2scSK FsMdOi32w/MamACw== Date: Wed, 11 Sep 2024 15:29:45 +0200 Subject: [PATCH 01/24] timekeeping: Read NTP tick length only once Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20240911-devel-anna-maria-b4-timers-ptp-timekeeping-v1-1-f7cae09e25d6@linutronix.de> References: <20240911-devel-anna-maria-b4-timers-ptp-timekeeping-v1-0-f7cae09e25d6@linutronix.de> In-Reply-To: <20240911-devel-anna-maria-b4-timers-ptp-timekeeping-v1-0-f7cae09e25d6@linutronix.de> To: John Stultz , Frederic Weisbecker , Thomas Gleixner Cc: linux-kernel@vger.kernel.org, netdev@vger.kernel.org, Miroslav Lichvar , Richard Cochran , Christopher S Hall , Anna-Maria Behnsen From: Thomas Gleixner No point in reading it a second time when the comparison fails. Signed-off-by: Thomas Gleixner Signed-off-by: Anna-Maria Behnsen --- kernel/time/timekeeping.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 5391e4167d60..b877173f88bb 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -2130,16 +2130,17 @@ static __always_inline void timekeeping_apply_adjustment(struct timekeeper *tk, */ static void timekeeping_adjust(struct timekeeper *tk, s64 offset) { + u64 ntp_tl = ntp_tick_length(); u32 mult; /* * Determine the multiplier from the current NTP tick length. * Avoid expensive division when the tick length doesn't change. */ - if (likely(tk->ntp_tick == ntp_tick_length())) { + if (likely(tk->ntp_tick == ntp_tl)) { mult = tk->tkr_mono.mult - tk->ntp_err_mult; } else { - tk->ntp_tick = ntp_tick_length(); + tk->ntp_tick = ntp_tl; mult = div64_u64((tk->ntp_tick >> tk->ntp_error_shift) - tk->xtime_remainder, tk->cycle_interval); }