From nobody Mon Feb 27 22:12:23 2023 X-Original-To: dev-commits-src-all@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4PQZVc3gc6z3tDyf; Mon, 27 Feb 2023 22:12:24 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4PQZVc0mVzz3Qn9; Mon, 27 Feb 2023 22:12:24 +0000 (UTC) (envelope-from git@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1677535944; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=33n5rkkzTzERa10GyYIgQskqMSCmTiMNML+Mjs4dzos=; b=Iy/wNd65MtiVpswMpngML7bvZ9QG+ANgc5Qp2kHJpwD85yUYs3NdqhdM801D/WJDWGVqRp EeMrorgWHRLMagRPoXZNXU/KaTEOA/4rPwoQhihT+ZcZAwjTQcgKbjWEWQw4D5usqsejUj Vl4QOqwHTf+8eG9xxflAyMxvHWbW53atc0q6G0x0lITkqn73oi5EKHegGwvWThKXVOetn7 Fz4z8T5Oe3p/SIRCjzhXy04XG1GFP+pQvYh0Z/+IVXGYD3/Hd+h4jKDj9meLCzyH3lzaVZ 9tfk/V+qATb4Jwbj4253LZ4tZPix8del3gmYmXyqk+2PMCvOKJxDZtQdarzO6w== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1677535944; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=33n5rkkzTzERa10GyYIgQskqMSCmTiMNML+Mjs4dzos=; b=an1kngNw7hbnY7g5dLOYbpuPkQ0iY7VaOEDrycNu+vWxnWMGzIfbEtl/u0RT75BghJhgI4 gW0FS/dvxhB1cPtDdRUY5kw4AKO27kF6b4svH1WeVAzlNyeDiEcijmFSprkXc/lzY0Z6KL h4tWUezAEUuDg8n13dEp0tRjcxrcmJvtgdmxQBmxtiB1qmWor9bXwX4QKARyhUYW8iRiWe lYSNLvuzoZ4mBvJKZ8V9LcAdkipL2ZlJWE+g6EnhTEXfYe5KT1tKvFxegETS3r/aO9n28n TQEahKjV7o0vgoHOHN1SEdJbJefpMyevduqFtHc9PdXpb+ZoMh6I9mJ6eppRZg== ARC-Authentication-Results: i=1; mx1.freebsd.org; none ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1677535944; a=rsa-sha256; cv=none; b=hcj8Z5Q52dE2N+HV6KmoPCKUTSfgZ4GoBStRLmAzF7/gy/5em6MfA2GSkf89nmxHnkPRID LWnyS2553dnpCuWp1w4aM5FBlw0HjO1mL09N/ob96+eThKBjGKFh7283qbCKEoM+wkL7qI fJ+ZLXm7HNlu0khLvQedUbLkxZl0fOnMEBFsBsc9Uh77kFLTidlxSsozYu+12LVt9O49DK dqSuipyiOt1NRy3I4l34tLAwboxIF3nK3CQxcAYa7kSoiJwoBlpNLGSuPnRs1Z2qQhG3iA d8O2FB64Q2Ly5t1C4jM2gttnkmDn5egk++TWGfwkupouI0XRApzJy/SZkLu8Aw== Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 4PQZVb6ymGzjVB; Mon, 27 Feb 2023 22:12:23 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org ([127.0.1.44]) by gitrepo.freebsd.org (8.16.1/8.16.1) with ESMTP id 31RMCN9v028876; Mon, 27 Feb 2023 22:12:23 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.16.1/8.16.1/Submit) id 31RMCNGU028875; Mon, 27 Feb 2023 22:12:23 GMT (envelope-from git) Date: Mon, 27 Feb 2023 22:12:23 GMT Message-Id: <202302272212.31RMCNGU028875@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org From: Warner Losh Subject: git: 28ed159f2669 - main - pps: Round to closest integer in pps_event() List-Id: Commit messages for all branches of the src repository List-Archive: https://lists.freebsd.org/archives/dev-commits-src-all List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-dev-commits-src-all@freebsd.org X-BeenThere: dev-commits-src-all@freebsd.org MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: imp X-Git-Repository: src X-Git-Refname: refs/heads/main X-Git-Reftype: branch X-Git-Commit: 28ed159f2669b8d401ca95bf5c6e9ff06a997ef9 Auto-Submitted: auto-generated X-ThisMailContainsUnwantedMimeParts: N The branch main has been updated by imp: URL: https://cgit.FreeBSD.org/src/commit/?id=28ed159f2669b8d401ca95bf5c6e9ff06a997ef9 commit 28ed159f2669b8d401ca95bf5c6e9ff06a997ef9 Author: Sebastian Huber AuthorDate: 2023-02-27 21:49:10 +0000 Commit: Warner Losh CommitDate: 2023-02-27 22:10:55 +0000 pps: Round to closest integer in pps_event() The comment above bintime2timespec() says: When converting between timestamps on parallel timescales of differing resolutions it is historical and scientific practice to round down. However, the delta_nsec value is a time difference and not a timestamp. Also the rounding errors accumulate in the frequency accumulator, see hardpps(). So, rounding to the closest integer is probably slightly better. Reviewed by: imp Pull Request: https://github.com/freebsd/freebsd-src/pull/604 --- sys/kern/kern_tc.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/sys/kern/kern_tc.c b/sys/kern/kern_tc.c index 0dc233896baa..e4b3d5e80529 100644 --- a/sys/kern/kern_tc.c +++ b/sys/kern/kern_tc.c @@ -1882,6 +1882,7 @@ pps_event(struct pps_state *pps, int event) #ifdef PPS_SYNC if (fhard) { uint64_t delta_nsec; + uint64_t freq; /* * Feed the NTP PLL/FLL. @@ -1893,7 +1894,8 @@ pps_event(struct pps_state *pps, int event) tcount &= captc->tc_counter_mask; delta_nsec = 1000000000; delta_nsec *= tcount; - delta_nsec /= captc->tc_frequency; + freq = captc->tc_frequency; + delta_nsec = (delta_nsec + freq / 2) / freq; hardpps(tsp, (long)delta_nsec); } #endif