From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935287AbcI0Te2 (ORCPT ); Tue, 27 Sep 2016 15:34:28 -0400 Received: from userp1040.oracle.com ([156.151.31.81]:18113 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754129AbcI0TeL (ORCPT ); Tue, 27 Sep 2016 15:34:11 -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, sam@ravnborg.org Cc: linux-kernel@vger.kernel.org, sparclinux@vger.kernel.org, babu.moger@oracle.com Subject: [PATCH v3 0/2] Ajust lockdep static allocations for sparc Date: Tue, 27 Sep 2016 12:33:26 -0700 Message-Id: <1475004808-91920-1-git-send-email-babu.moger@oracle.com> X-Mailer: git-send-email 1.7.1 X-Source-IP: userv0021.oracle.com [156.151.31.71] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org These patches limit the static allocations for lockdep data structures used for debugging locking correctness. For sparc, all the kernel's code, data, and bss, must have locked translations in the TLB so that we don't get TLB misses on kernel code and data. 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. With PROVE_LOCKING we could go over this limit and cause system boot-up problems. These patches limit the static allocations so that everything fits in current required size limit. patch 1 : Adds new config parameter CONFIG_PROVE_LOCKING_SMALL Patch 2 : Adjusts the sizes based on the new config parameter v2-> v3: Some more comments from Sam Ravnborg and Peter Zijlstra. Defined PROVE_LOCKING_SMALL as invisible and moved the selection to arch/sparc/Kconfig. v1-> v2: As suggested by Peter Zijlstra, keeping the default as is. Introduced new config variable CONFIG_PROVE_LOCKING_SMALL to handle sparc specific case. v0: Initial revision. Babu Moger (2): config: Adding the new config parameter CONFIG_PROVE_LOCKING_SMALL for sparc lockdep: Limit static allocations if PROVE_LOCKING_SMALL is defined arch/sparc/Kconfig | 1 + kernel/locking/lockdep_internals.h | 20 +++++++++++++++++--- lib/Kconfig.debug | 3 +++ 3 files changed, 21 insertions(+), 3 deletions(-)