From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 543F4C433EF for ; Thu, 14 Apr 2022 11:39:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242729AbiDNLlZ (ORCPT ); Thu, 14 Apr 2022 07:41:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44388 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231670AbiDNLlY (ORCPT ); Thu, 14 Apr 2022 07:41:24 -0400 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0DD2D86E2A; Thu, 14 Apr 2022 04:39:00 -0700 (PDT) From: Kurt Kanzenbach DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1649936338; 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: in-reply-to:in-reply-to:references:references; bh=2AY30W6+ipE8tv0jnqpr+K7cq6+IFyrSuzCK12VLVYw=; b=GvUF1qynsCri8gGc/nnSyUDUek7DQ6jMg16N+aPbQbJ+qOCaqxr/gchfcQgCP4CdDBcDJi /n8EkfW0upDMiG7wqh5LTmgHhnPcXyHItYogqCYU7AgSikCvdeJ+v3EyUCvOJ1VvYIuGuG CW2+N2oNctK6XtYlt9E6uEbPJw8C9XSvni2JrjSF56GaG5BjafrJeejq0jpOjOAyUBRXgL 2aHL0KFWYmmX6BvTsvUlodKVRzQSdEMcs77D5gO+XXAeHDx9zS3RwGWy9mOu0qiPT3xtFo /hEy2jz4ihatSM3QuCC7ojjH/YdrV7nNeINUs/C5rbnRsfEi3rM9HMj3QrAyiQ== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1649936338; 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: in-reply-to:in-reply-to:references:references; bh=2AY30W6+ipE8tv0jnqpr+K7cq6+IFyrSuzCK12VLVYw=; b=S+AwNNkvqObJWBQolXrNzbKLfkL/JniTJpw1MsVEqNFGg4huV56FZfEChGXdfN/MJ0UNpV MzDqA97AeFO/IkDw== To: Bagas Sanjaya , John Stultz , Thomas Gleixner , Stephen Boyd , Steven Rostedt , Ingo Molnar , Jonathan Corbet Cc: Richard Cochran , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 3/3] tracing: Add documentation for trace clock tai In-Reply-To: <0dd9ba0e-712a-37f6-a50d-f5510cd23033@gmail.com> References: <20220414091805.89667-1-kurt@linutronix.de> <20220414091805.89667-4-kurt@linutronix.de> <0dd9ba0e-712a-37f6-a50d-f5510cd23033@gmail.com> Date: Thu, 14 Apr 2022 13:38:57 +0200 Message-ID: <871qxzq4ha.fsf@kurt> MIME-Version: 1.0 Content-Type: multipart/signed; boundary="=-=-="; micalg=pgp-sha512; protocol="application/pgp-signature" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --=-=-= Content-Type: text/plain On Thu Apr 14 2022, Bagas Sanjaya wrote: > On 4/14/22 16:18, Kurt Kanzenbach wrote: >> + tai: >> + This is the tai clock (CLOCK_TAI) and is derived from the wall- >> + clock time. However, this clock does not experience >> + discontinuities and backwards jumps caused by NTP inserting leap >> + seconds. Since the clock access is designed for use in tracing, >> + side effects are possible. The clock access may yield wrong >> + readouts in case the internal TAI offset is updated e.g., caused >> + by setting the system time or using adjtimex() with an offset. >> + These effects are rare and post processing should be able to >> + handle them. See comments in the ktime_get_tai_fast_ns() >> + function for more information. >> + > > In what file are the ktime_get_tai_fast_ns() comments? In kernel/time/timekeeping.c. That function is introduced in patch #1 and has kernel doc comments. Similar to ktime_get_boot_fast_ns(). Thanks, Kurt --=-=-= Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQJHBAEBCgAxFiEEvLm/ssjDfdPf21mSwZPR8qpGc4IFAmJYB9ETHGt1cnRAbGlu dXRyb25peC5kZQAKCRDBk9HyqkZzgicJD/9A7CLbPVNGF89I2TFog7qSZXhTkEDx G1J3fJZkFtdv7+zSrNWqHPiYZcbMAOUX6Txe0aRqEV5dfNta+8i9w1zpLKVSw84V lOHlYb5pF03sZ1iqIgFvPKx9wym+1w9dFDNqL/hp+T1FaSjVhzj3MFZh/nFKcgO0 m105ui2jQI/VRLRfoGn6C5l+EmEYlb7D4ohTBfjolPirwAm1UUluIZlV6DOuVCxq ic6U6NlFRSN/gTaJMr1i3g/QGw0CSHfqGcUT52YWQXAS5kjuL8yLxsIWt9nAL7N/ bmc65bJVmLmxItIgKYQipZxB/2cKqnQsJWR5sxCNSCy1xZ2c4fLKpfckWqZzL4Rg kz3xKx70eiV1Lvojh4TyaqHqTftMk2HNaOouchFWcwQAYEeYhkK32f5PnEJ0FRMt Lp2PHJrpIxQMbAMLXIwKbV/AQCgtxYP8niMYkzDdEGV2Fku3mVracJ4cMFVBmC/5 f9sWlOzhilkM2cC1ajvQt4g2QkzjBVj6a1ivN3wULsc2AuBRj89EWJbYfGqxE212 MxxPKy8JhE0igm6OAS9QV7el4D+oKG1ExHeFNb0iSBjU9SmhWlUML+H+WrwWjGGb irQ6zqrCrgjIiyQDxu9pA9qoLcUOFP4r1ZVxMgdZLvvwKzuQuCfc44eKWLmD0KA8 lHVcM/IpaRwzBA== =u8Ks -----END PGP SIGNATURE----- --=-=-=--