From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933370AbcIZWcy (ORCPT ); Mon, 26 Sep 2016 18:32:54 -0400 Received: from aserp1040.oracle.com ([141.146.126.69]:51261 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S941889AbcIZWc0 (ORCPT ); Mon, 26 Sep 2016 18:32:26 -0400 From: Babu Moger To: peterz@infradead.org, mingo@redhat.com, akpm@linux-foundation.org, keescook@chromium.org, dan.j.williams@intel.com, aryabinin@virtuozzo.com, tj@kernel.org Cc: linux-kernel@vger.kernel.org, sparclinux@vger.kernel.org, babu.moger@oracle.com Subject: [PATCH v2 1/2] config: Add new CONFIG_PROVE_LOCKING_SMALL Date: Mon, 26 Sep 2016 15:31:37 -0700 Message-Id: <1474929098-68914-2-git-send-email-babu.moger@oracle.com> X-Mailer: git-send-email 1.7.1 In-Reply-To: <1474929098-68914-1-git-send-email-babu.moger@oracle.com> References: <1474929098-68914-1-git-send-email-babu.moger@oracle.com> X-Source-IP: userv0022.oracle.com [156.151.31.74] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Adding the new config parameter CONFIG_PROVE_LOCKING_SMALL for sparc. This feature limits the space used for "Lock debugging: prove locking correctness" by about 4MB. The current sparc systms have the limitation of 32MB size for kernel size including .text, .data and .bss sections. With PROVE_LOCKING feature, the kernel size could grow beyond this limit and causing system bootup issues. With this option, kernel limits the size of the entries of lock_chains, stack_trace etc. so that kernel fits in required size limit. This is only visible for sparc. Signed-off-by: Babu Moger --- lib/Kconfig.debug | 17 +++++++++++++++++ 1 files changed, 17 insertions(+), 0 deletions(-) diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index b9cfdbf..c79de25 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -1035,6 +1035,7 @@ config PROVE_LOCKING select DEBUG_MUTEXES select DEBUG_LOCK_ALLOC select TRACE_IRQFLAGS + select PROVE_LOCKING_SMALL if SPARC default n help This feature enables the kernel to prove that all locking @@ -1070,6 +1071,22 @@ config PROVE_LOCKING For more details, see Documentation/locking/lockdep-design.txt. +config PROVE_LOCKING_SMALL + bool "Limit the space for prove locking correctness" + depends on PROVE_LOCKING && SPARC + help + This feature limits the space used for "Lock debugging: prove + locking correctness" by about 4MB. In sparc system, all the + kernel's code, data, and bss, must have locked translations in + the TLB so that it does not hit TLB misses. The current sparc + chips have 8 TLB entries available that may be locked down, and + with a 4mb page size, this gives a maximum of 32mb of memory for + the kernel size. With PROVE_LOCKING feature, the kernel size could + grow beyond this limit and causing system bootup issues. With + this option, kernel limits the size of the entries of lock_chains, + stack_trace etc. to debug PROVE_LOCKING so that kernel size fits + in 32MB. This is only visible for SPARC. + config LOCKDEP bool depends on DEBUG_KERNEL && TRACE_IRQFLAGS_SUPPORT && STACKTRACE_SUPPORT && LOCKDEP_SUPPORT -- 1.7.1