Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932340AbcJPP5M (ORCPT ); Sun, 16 Oct 2016 11:57:12 -0400 Received: from aserp1040.oracle.com ([141.146.126.69]:46654 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757346AbcJPP4x (ORCPT ); Sun, 16 Oct 2016 11:56:53 -0400 From: Vegard Nossum To: Akinobu Mita Cc: linux-kernel@vger.kernel.org, Vegard Nossum , Peter Zijlstra , Ingo Molnar Subject: [PATCH 09/10] fault injection: spin_trylock() fault injection Date: Sun, 16 Oct 2016 17:56:11 +0200 Message-Id: <20161016155612.4784-9-vegard.nossum@oracle.com> X-Mailer: git-send-email 2.10.0.479.g221bd91 In-Reply-To: <20161016155612.4784-1-vegard.nossum@oracle.com> References: <20161016155612.4784-1-vegard.nossum@oracle.com> X-Source-IP: aserv0022.oracle.com [141.146.126.234] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2453 Lines: 87 Cc: Peter Zijlstra Cc: Ingo Molnar Signed-off-by: Vegard Nossum --- include/linux/spinlock.h | 12 ++++++++++++ kernel/locking/spinlock.c | 19 +++++++++++++++++++ lib/Kconfig.debug | 6 ++++++ 3 files changed, 37 insertions(+) diff --git a/include/linux/spinlock.h b/include/linux/spinlock.h index 47dd0ce..2fd1fee 100644 --- a/include/linux/spinlock.h +++ b/include/linux/spinlock.h @@ -307,8 +307,20 @@ static __always_inline void spin_lock_bh(spinlock_t *lock) raw_spin_lock_bh(&lock->rlock); } +#if defined(CONFIG_SMP) && defined(CONFIG_FAIL_SPINLOCK) +extern bool should_fail_spinlock(spinlock_t *lock); +#else +static __always_inline bool should_fail_spinlock(spinlock_t *lock) +{ + return false; +} +#endif + static __always_inline int spin_trylock(spinlock_t *lock) { + if (should_fail_spinlock(lock)) + return 0; + return raw_spin_trylock(&lock->rlock); } diff --git a/kernel/locking/spinlock.c b/kernel/locking/spinlock.c index db3ccb1..d57800f 100644 --- a/kernel/locking/spinlock.c +++ b/kernel/locking/spinlock.c @@ -14,6 +14,7 @@ * frame contact the architecture maintainers. */ +#include #include #include #include @@ -405,3 +406,21 @@ notrace int in_lock_functions(unsigned long addr) && addr < (unsigned long)__lock_text_end; } EXPORT_SYMBOL(in_lock_functions); + +#ifdef CONFIG_FAIL_SPINLOCK +static DECLARE_FAULT_ATTR(fail_spinlock); + +static int __init fail_spinlock_debugfs(void) +{ + struct dentry *dir = fault_create_debugfs_attr("fail_spinlock", + NULL, &fail_spinlock); + return PTR_ERR_OR_ZERO(dir); +} +late_initcall(fail_spinlock_debugfs); + +bool should_fail_spinlock(spinlock_t *lock) +{ + return should_fail(&fail_spinlock, 1); +} + +#endif diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 342f0a1f..1f13d02 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -1681,6 +1681,12 @@ config FAIL_RW_SEMAPHORE help Provide fault-injection capability for down_{read,write}_trylock(). +config FAIL_SPINLOCK + bool "Fault-injection capability for spinlocks" + depends on FAULT_INJECTION + help + Provide fault-injection capability for spin_trylock(). + config FAULT_INJECTION_DEBUG_FS bool "Debugfs entries for fault-injection capabilities" depends on FAULT_INJECTION && SYSFS && DEBUG_FS -- 2.10.0.479.g221bd91