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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 3CAD1C3DA4A for ; Fri, 16 Aug 2024 10:14:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=LO/iow1SbJ8bZgOeE7NZWZK6ui9kntdejMHnbs/E1nM=; b=v/s0oMVyqo8HEZ3xpdpsHswRhz WOcWOAxhAhOLIPvMedH6lZLd4BRPXSx6wI4aQEz4NcTqBcJpuzMYcNlBYwvxQFupMNoDImlXMmvvB WFTU0kXg4kNZZSLTgcAfrI5EVfOBohPpAiGM0OYYvFnyJQ6oufN7dSKViphsVDkeTV68WVhuk3xMk P/a1pQpM5xnw36S1XhBAuW/BbGiG06p4QisdjGZhEWMNAF/o40QYyndoGYVsaQtx8Gwts4gfmwS5y 9Nr/fCa925Dcj++UMalaMrBhl/z8RygPOTse0QZgxMdKxsWEOmJiIAx//NS3tZZ/5tRMOOPINzsT2 vQrIjrrQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1setyq-0000000CYhb-0Uks; Fri, 16 Aug 2024 10:14:48 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1setyB-0000000CYac-2zrG for linux-arm-kernel@lists.infradead.org; Fri, 16 Aug 2024 10:14:09 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 0EEF6143D; Fri, 16 Aug 2024 03:14:33 -0700 (PDT) Received: from J2N7QTR9R3 (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 0C6333F73B; Fri, 16 Aug 2024 03:14:05 -0700 (PDT) Date: Fri, 16 Aug 2024 11:14:03 +0100 From: Mark Rutland To: Robin Murphy Cc: will@kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, ilkka@os.amperecomputing.com Subject: Re: [PATCH 3/8] perf/arm-cmn: Ensure dtm_idx is big enough Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240816_031407_829305_37CDB4AF X-CRM114-Status: GOOD ( 17.34 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, Aug 09, 2024 at 08:15:42PM +0100, Robin Murphy wrote: > While CMN_MAX_DIMENSION was bumped to 12 for CMN-650, that only supports > up to a 10x10 mesh, so bumping dtm_idx to 256 bits at the time worked > out OK in practice. However CMN-700 did finally support up to 144 XPs, > and thus needs a worst-case 288 bits of dtm_idx for an aggregated XP > event on a maxed-out config. Oops. > > Fixes: 23760a014417 ("perf/arm-cmn: Add CMN-700 support") > Signed-off-by: Robin Murphy > --- > drivers/perf/arm-cmn.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/perf/arm-cmn.c b/drivers/perf/arm-cmn.c > index 0e2e12e2f4fb..c9a2b21a7aec 100644 > --- a/drivers/perf/arm-cmn.c > +++ b/drivers/perf/arm-cmn.c > @@ -563,7 +563,7 @@ static void arm_cmn_debugfs_init(struct arm_cmn *cmn, int id) {} > > struct arm_cmn_hw_event { > struct arm_cmn_node *dn; > - u64 dtm_idx[4]; > + u64 dtm_idx[5]; Can't we size this based on CMN_MAX_DIMENSION (or CMN_MAX_XPS or CMN_MAX_DTMS), to make that clear? >From the desciription in the commit message it sounds like you need 2 * CMN_MAX_XPS bits, i.e. #define DTM_IDX_BITS (2 * CMN_MAX_XPS) u64 dtm_idx[DIV_ROUND_UP(DTM_IDX_BITS, 64)]; Mark. > s8 dtc_idx[CMN_MAX_DTCS]; > u8 num_dns; > u8 dtm_offset; > -- > 2.39.2.101.g768bb238c484.dirty >