From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753200AbbCZShu (ORCPT ); Thu, 26 Mar 2015 14:37:50 -0400 Received: from mga11.intel.com ([192.55.52.93]:42654 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752699AbbCZSd3 (ORCPT ); Thu, 26 Mar 2015 14:33:29 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.11,474,1422950400"; d="scan'208";a="546857743" Subject: [PATCH 06/17] x86, mpx: trace attempts to find bounds tables To: linux-kernel@vger.kernel.org Cc: x86@kernel.org, tglx@linutronix.de, Dave Hansen , dave.hansen@linux.intel.com From: Dave Hansen Date: Thu, 26 Mar 2015 11:33:41 -0700 References: <20150326183327.64807530@viggo.jf.intel.com> In-Reply-To: <20150326183327.64807530@viggo.jf.intel.com> Message-Id: <20150326183341.A0AA7CBF@viggo.jf.intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Dave Hansen This event traces any time we go looking to unmap a bounds table for a given virtual address range. This is useful to ensure that the kernel actually "tried" to free a bounds table versus times it succeeded. It might try and fail if it realized that a table was shared with an adjacent VMA which is not being unmapped. Signed-off-by: Dave Hansen --- b/arch/x86/include/asm/trace/mpx.h | 22 ++++++++++++++++++++++ b/arch/x86/mm/mpx.c | 1 + 2 files changed, 23 insertions(+) diff -puN arch/x86/include/asm/trace/mpx.h~mpx-trace_unmap_search arch/x86/include/asm/trace/mpx.h --- a/arch/x86/include/asm/trace/mpx.h~mpx-trace_unmap_search 2015-03-26 11:27:06.684292099 -0700 +++ b/arch/x86/include/asm/trace/mpx.h 2015-03-26 11:27:06.689292324 -0700 @@ -75,6 +75,28 @@ TRACE_EVENT(mpx_unmap_zap, ) ); +TRACE_EVENT(mpx_unmap_search, + + TP_PROTO(unsigned long start, + unsigned long end), + TP_ARGS(start, end), + + TP_STRUCT__entry( + __field(unsigned long, start) + __field(unsigned long, end) + ), + + TP_fast_assign( + __entry->start = start; + __entry->end = end; + ), + + TP_printk("0x%p -> 0x%p", + (void *)__entry->start, + (void *)__entry->end + ) +); + #else /* diff -puN arch/x86/mm/mpx.c~mpx-trace_unmap_search arch/x86/mm/mpx.c --- a/arch/x86/mm/mpx.c~mpx-trace_unmap_search 2015-03-26 11:27:06.686292189 -0700 +++ b/arch/x86/mm/mpx.c 2015-03-26 11:27:06.689292324 -0700 @@ -843,6 +843,7 @@ static int mpx_unmap_tables(struct mm_st long __user *bd_entry, *bde_start, *bde_end; unsigned long bt_addr; + trace_mpx_unmap_search(start, end); /* * "Edge" bounds tables are those which are being used by the region * (start -> end), but that may be shared with adjacent areas. If they _