From mboxrd@z Thu Jan 1 00:00:00 1970 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 AE10C286298 for ; Fri, 21 Feb 2025 16:21:49 +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=1740154911; cv=none; b=cOtFaYcFlbd8R+bTOn5hPoKBV1psOiS/EEb8bfhsypGVDly72cliHkknKdq1ZrAO6YGk9WQGKb584EU1BwAN3Ld5UFgG8Bkhu5yDuLaWOaFH4QZ1+DbUU0MY630kXAhH65lENXvPUWejYifDLet4xfw6EB9barx3wcs+Zlin19k= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740154911; c=relaxed/simple; bh=JXXDhl0nQx8ambNwC5NcULIC1KZ5B+o5lMThPcTak0A=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=UCqe6JZomx+vTeQqLJoxLW4dY9X8KIBb7oxDSA2vfBgyJwertFSmAJzzL2iQKxH9IkQkgJgGKvsGJ023CWFuGdL+bCwAFSm0MEQFTVayVWzNWXFkzSOt2LqnBIwUSFdFPVNwk9gmfb7fGF2qSv3sFuzBL9/K034rr6rYkLvDdXk= 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=ttq10+1z; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=qkyHEI97; 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="ttq10+1z"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="qkyHEI97" Date: Fri, 21 Feb 2025 17:21:46 +0100 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1740154907; 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=PA4k5F6EACYZgIJqap1nUVHDZ6mAhivK4Kn2VFbKjYw=; b=ttq10+1zAuPBqrizPUXC80Tz2RwSz7Rr8qHQKTaaH2oYiN/H2visli+TyCHgQHlz6blhWl hzMHMjUxMnPZ4jYnojp0bMsb90l04szTnngISRekFdSOJUIzKEnNuvZgI5zFrGdCsEFXQv wDo2wdEF9/RFP8Nz8lq+N2pIMDQLcIH+fnwJhgc/7RONMi1FeVs/sc0i4izdQ5vPrkxA7H F7Go0WU92hJDQYaO1dGtskYZFNpQPWWz0g20tCZBq+rhWcCc4+bGs7oU8QTLYOdWfEvIiM RE1Lhzzu2sJQNhzODNUOCfoprJpLsevR+E0rQ2woMDqk1gkZpi6aw3MhXsgGSA== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1740154907; 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=PA4k5F6EACYZgIJqap1nUVHDZ6mAhivK4Kn2VFbKjYw=; b=qkyHEI97a68yz06hiQtRmnWZWX9bzMChqr2wHOo2MSeBsBvtFl+SzSXqqsO1RodrX1ivQh uP1b47rCBSkdHlCw== From: Sebastian Andrzej Siewior To: Steven Rostedt Cc: Wander Lairson Costa , linux-trace-kernel@vger.kernel.org, Masami Hiramatsu , Mathieu Desnoyers , Thomas Gleixner Subject: Re: [PATCH] ftrace: Correct preemption accounting for function tracing. Message-ID: <20250221162146.9KWeIdA0@linutronix.de> References: <20250220140749.pfw8qoNZ@linutronix.de> <44ymxgot422oetab62w55rth5tqrzseyhwirxg2ho7vzvvkaud@qiada52ckt25> <20250220115400.4d75d881@gandalf.local.home> Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable In-Reply-To: <20250220115400.4d75d881@gandalf.local.home> On 2025-02-20 11:54:00 [-0500], Steven Rostedt wrote: > > kworker/0:5-88 [000] D.Zf2 211.983391: igbvf_reset_L14: (ig= bvf_reset+0x62/0x120 [igbvf]) > > kworker/0:5-88 [000] .N... 211.983396: igbvf_reset_L16: (ig= bvf_reset+0x7b/0x120 [igbvf]) =E2=80=A6 > > (Except in line 6 where it show 'f', which seems to be an unrelated iss= ue) >=20 > But it appears to be consistent. >=20 > Let me go and add some probes and see what they show. The output you gave > me that I requested didn't show anything unusual. Since I just noticed that you posted the patches, did you find anything? =46rom looking at it, if we preemption at 0, migrate disable at 3 then a substraction of one would underflow the preemption counter to f and migrate disable to 2. But based on code inspection mg should be at 1. And this does not explain where D & Z is coming from. > -- Steve Sebastian