From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from one.firstfloor.org (one.firstfloor.org [65.21.254.221]) (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 A86E444062D for ; Wed, 19 Aug 2026 18:25:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=65.21.254.221 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787163932; cv=none; b=FB5CHQ6rU0RTK7zRW/ib4amF29NbZiR88zcb17aaAv9RmXYCGecrFMs5g9Z2J++ARdwxXzvvt7/PIK9gE6VRbNxSDrqbJhabh4wAHdXmhRqkextKWfhNxoyum5V7ADjhOj5r3XcBXKDgRnYleQ6FENKrpOpiGYtlqNTRC6CePBs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787163932; c=relaxed/simple; bh=hk839zjCyZVZCvGzHzk1OczIXwLj5ns5KxczH/Jy11k=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=fTm/V7SQBvmQFg6izajoU12NWX3Ayal2UcPisrTjxpqkyEcBXLMtKrprQnOl5QzoEmA+cFYmjD9YujhQrKmrcsyEKQm5ULiFTXZgnKuxNNwn9sp351glcoWG/CobFet+3oI+hBDaggUxa86hcKRR34XVb9QdmAW93378FeKSevk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=firstfloor.org; spf=pass smtp.mailfrom=firstfloor.org; dkim=pass (1024-bit key) header.d=firstfloor.org header.i=@firstfloor.org header.b=oSWx8YPg; arc=none smtp.client-ip=65.21.254.221 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=firstfloor.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=firstfloor.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=firstfloor.org header.i=@firstfloor.org header.b="oSWx8YPg" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=firstfloor.org; s=mail; t=1787163927; bh=hk839zjCyZVZCvGzHzk1OczIXwLj5ns5KxczH/Jy11k=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=oSWx8YPgYQtkrc0Y7TWuGUzKGgqaxaHZaDr19+DJWkYPySFy/WXtr7rLy4YYq458v 3q/gCCk+yItKI63GHsSEBqnYrt8+Lho8pnj8GgRJnWyHyRfnZGa9lqgJt8ptk9xvtp nERxV9CdXeChYqPcknVon2/zeuNvWsE4XB0Qf+2M= Received: by one.firstfloor.org (Postfix, from userid 503) id 0F2735E89E; Wed, 19 Aug 2026 20:25:27 +0200 (CEST) Date: Wed, 19 Aug 2026 11:25:27 -0700 From: Andi Kleen To: Ian Rogers Cc: Andi Kleen , namhyung@kernel.org, acme@kernel.org, linux-perf-users@vger.kernel.org, Andi Kleen Subject: Re: [PATCH v1] perf top: Merge hybrid common events Message-ID: References: <20260813132519.4099508-1-andi@firstfloor.org> <7f5ae51dea8c7b6770716dedc46ee1b3@firstfloor.org> Precedence: bulk X-Mailing-List: linux-perf-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: > So I think we can add a json field to indicate mergeability and set it > on legacy instructions, perhaps things like branches and > branch-misses But the current simple check already works fine for them? >. We can also detect a hybrid system and switch from > cycles to instructions as the default event when merging is desired > (like in perf top). instructions rarely gives you an accurate breakdown because the IPC varies so much in practice. cycles is a much better default. The other things are reasonable I guess, but all not really needed initially. -Andi