From nobody Sat Oct 4 08:03:05 2025 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (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 9DEE4326D48 for ; Tue, 19 Aug 2025 20:14:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755634467; cv=none; b=GwVx7CdG80PmnNEj5tGZBZ0Of7rV/1QDWc0ukcfFnxJwyIZK7cgbfAc0YqZW8J+iKdTORKhI4dAeNeb8TKO/lVYls7Vm1+oY0qp+zNMjV27+PRGY1qyh07zvRHzXPO34njpRfnWDgL+d+vVLS3mJSwgNeKmkcE0r1deinix/d9w= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755634467; c=relaxed/simple; bh=JcG8AO1bHRvEK0uCkPbFr4Yzn72QSE/1a/I9KFT6zpE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=DIIGKbrHhs4NCSbwNfOk4JyQJiV/l2tXYvbe7lJyFkDQD1AbgWaP4QFO6a3iw5SwOOkDMlFq+CiePc3irUhtJyuQvhfSvKZSPoX8b5x2RflUAzq3qoncDK6tnkh9qZ3AJCXBiEDvC6dXYNjPq5UGFPzxRodzkUnFpDaZy4gelj0= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=baDHRkTg; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="baDHRkTg" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1755634464; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=VDxx71q3MVhyRyVcbCfH/wubs1F7yPIXcuCK3By5m/4=; b=baDHRkTgQRJce9w7GQoLOSNNVCeyxZjo0AgEEM3egI/CHzw3DAWW7EsAgp+LBtjqke9Rim jJLW4Z1Bo89UF77uAJe8p0mpbUJ3LZ/px+rbDXRtud42qet/sTKXg3u1XH4vp64JXRYH9f E/HQg8JNgVX4iAMTyf10tkOxqiqUxiY= Received: from mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-298-ssaWOvdYMI2VVfIdHjYDCg-1; Tue, 19 Aug 2025 16:14:23 -0400 X-MC-Unique: ssaWOvdYMI2VVfIdHjYDCg-1 X-Mimecast-MFC-AGG-ID: ssaWOvdYMI2VVfIdHjYDCg_1755634460 Received: from mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.12]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 5A94F1954228; Tue, 19 Aug 2025 20:14:20 +0000 (UTC) Received: from chopper.redhat.com (unknown [10.22.81.238]) by mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id D414D19560B2; Tue, 19 Aug 2025 20:14:16 +0000 (UTC) From: Lyude Paul To: rust-for-linux@vger.kernel.org, linux-kernel@vger.kernel.org, Thomas Gleixner , Andreas Hindborg , FUJITA Tomonori Cc: Boqun Feng , Frederic Weisbecker , Anna-Maria Behnsen , John Stultz , Stephen Boyd , Miguel Ojeda , Alex Gaynor , Gary Guo , =?UTF-8?q?Bj=C3=B6rn=20Roy=20Baron?= , Benno Lossin , Alice Ryhl , Trevor Gross , Danilo Krummrich Subject: [PATCH v8 6/7] rust: time: Add Instant::from_ktime() Date: Tue, 19 Aug 2025 16:05:57 -0400 Message-ID: <20250819201334.545001-7-lyude@redhat.com> In-Reply-To: <20250819201334.545001-1-lyude@redhat.com> References: <20250819201334.545001-1-lyude@redhat.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.0 on 10.30.177.12 Content-Type: text/plain; charset="utf-8" For implementing Rust bindings which can return a point in time. Signed-off-by: Lyude Paul --- V4: * Turn from_nanos() into an unsafe function in order to ensure that we uphold the invariants of Instant V5: * Add debug_assert!() to from_nanos V8: * Change name of function from Instant::from_nanos() to Instant::from_ktime() rust/kernel/time.rs | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) diff --git a/rust/kernel/time.rs b/rust/kernel/time.rs index 64c8dcf548d63..5c40ebe096357 100644 --- a/rust/kernel/time.rs +++ b/rust/kernel/time.rs @@ -200,6 +200,29 @@ pub fn elapsed(&self) -> Delta { pub(crate) fn as_nanos(&self) -> i64 { self.inner } + + /// Create an [`Instant`] from a `ktime_t` without checking if it is n= on-negative. + /// + /// # Panics + /// + /// On debug builds, this function will panic if `nanos` is not in the= range from 0 to + /// `KTIME_MAX`. + /// + /// # Safety + /// + /// The caller promises that `nanos` is in the range from 0 to `KTIME_= MAX`. + #[expect(unused)] + #[inline] + pub(crate) unsafe fn from_ktime(ktime: bindings::ktime_t) -> Self { + debug_assert!(ktime >=3D 0); + + // INVARIANT: Our safety contract ensures that `nanos` is in the r= ange from 0 to + // `KTIME_MAX`. + Self { + inner: ktime, + _c: PhantomData, + } + } } =20 impl core::ops::Sub for Instant { --=20 2.50.0