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 X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id EAA24C3A59E for ; Wed, 21 Aug 2019 12:48:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C96DC22CF7 for ; Wed, 21 Aug 2019 12:48:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728521AbfHUMs0 (ORCPT ); Wed, 21 Aug 2019 08:48:26 -0400 Received: from mga07.intel.com ([134.134.136.100]:30850 "EHLO mga07.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728357AbfHUMsJ (ORCPT ); Wed, 21 Aug 2019 08:48:09 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by orsmga105.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 21 Aug 2019 05:48:08 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.64,412,1559545200"; d="scan'208";a="207724904" Received: from black.fi.intel.com (HELO black.fi.intel.com.) ([10.237.72.28]) by fmsmga002.fm.intel.com with ESMTP; 21 Aug 2019 05:48:07 -0700 From: Alexander Shishkin To: Peter Zijlstra Cc: Arnaldo Carvalho de Melo , Ingo Molnar , linux-kernel@vger.kernel.org, Alexander Shishkin Subject: [PATCH v0 3/6] perf/x86/intel/pt: Use pointer arithmetics instead in ToPA entry calculation Date: Wed, 21 Aug 2019 15:47:24 +0300 Message-Id: <20190821124727.73310-4-alexander.shishkin@linux.intel.com> X-Mailer: git-send-email 2.23.0.rc1 In-Reply-To: <20190821124727.73310-1-alexander.shishkin@linux.intel.com> References: <20190821124727.73310-1-alexander.shishkin@linux.intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Currently, pt_buffer_reset_offsets() calculates the current ToPA entry by casting pointers to addresses and performing ungainly subtractions and divisions instead of a simpler pointer arithmetic, which would be perfectly applicable in that case. Fix that. Signed-off-by: Alexander Shishkin --- arch/x86/events/intel/pt.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/arch/x86/events/intel/pt.c b/arch/x86/events/intel/pt.c index 831163a1b41a..15e7c11e3460 100644 --- a/arch/x86/events/intel/pt.c +++ b/arch/x86/events/intel/pt.c @@ -1030,8 +1030,7 @@ static void pt_buffer_reset_offsets(struct pt_buffer *buf, unsigned long head) pg = pt_topa_next_entry(buf, pg); buf->cur = (struct topa *)((unsigned long)buf->topa_index[pg] & PAGE_MASK); - buf->cur_idx = ((unsigned long)buf->topa_index[pg] - - (unsigned long)buf->cur) / sizeof(struct topa_entry); + buf->cur_idx = buf->topa_index[pg] - TOPA_ENTRY(buf->cur, 0); buf->output_off = head & (pt_buffer_region_size(buf) - 1); local64_set(&buf->head, head); -- 2.23.0.rc1