Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752890AbdHWAKp (ORCPT ); Tue, 22 Aug 2017 20:10:45 -0400 Received: from mail-pg0-f68.google.com ([74.125.83.68]:34620 "EHLO mail-pg0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752770AbdHWAKk (ORCPT ); Tue, 22 Aug 2017 20:10:40 -0400 MIME-Version: 1.0 In-Reply-To: <20170822230043.9968-2-bart.vanassche@wdc.com> References: <20170822230043.9968-1-bart.vanassche@wdc.com> <20170822230043.9968-2-bart.vanassche@wdc.com> From: Akinobu Mita Date: Wed, 23 Aug 2017 09:10:19 +0900 Message-ID: Subject: Re: [PATCH v2 1/2] fault-inject: Restore support for task-independent fault injection To: Bart Van Assche Cc: Andrew Morton , linux-block@vger.kernel.org, LKML , Dmitry Vyukov , Michal Hocko Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3977 Lines: 88 2017-08-23 8:00 GMT+09:00 Bart Van Assche : > Certain faults should be injected independent of the context > in which these occur. Commit e41d58185f14 made it impossible to > inject faults independent of their context. Restore support for > task-independent fault injection by adding the attribute 'global'. There was a the problem reported by fail-make-request user and the problem is introduced by the follow-up patches for systematic fault injection. Please check the commit 9eeb52ae712e ("fault-inject: fix wrong should_fail() decision in task context") and see if the problem you reported is identical to the commit. > References: commit e41d58185f14 ("fault-inject: support systematic fault injection") > Signed-off-by: Bart Van Assche > Cc: Dmitry Vyukov > Cc: Akinobu Mita > Cc: Michal Hocko > Cc: Andrew Morton > --- > include/linux/fault-inject.h | 11 +++++++++-- > lib/fault-inject.c | 4 +++- > 2 files changed, 12 insertions(+), 3 deletions(-) > > diff --git a/include/linux/fault-inject.h b/include/linux/fault-inject.h > index 728d4e0292aa..88dae2f21881 100644 > --- a/include/linux/fault-inject.h > +++ b/include/linux/fault-inject.h > @@ -18,6 +18,7 @@ struct fault_attr { > atomic_t times; > atomic_t space; > unsigned long verbose; > + bool global; > bool task_filter; > unsigned long stacktrace_depth; > unsigned long require_start; > @@ -30,17 +31,23 @@ struct fault_attr { > struct dentry *dname; > }; > > -#define FAULT_ATTR_INITIALIZER { \ > +#define __FAULT_ATTR_INITIALIZER(__global) { \ > .interval = 1, \ > .times = ATOMIC_INIT(1), \ > .require_end = ULONG_MAX, \ > + .global = (__global), \ > .stacktrace_depth = 32, \ > .ratelimit_state = RATELIMIT_STATE_INIT_DISABLED, \ > .verbose = 2, \ > .dname = NULL, \ > } > > -#define DECLARE_FAULT_ATTR(name) struct fault_attr name = FAULT_ATTR_INITIALIZER > +#define FAULT_ATTR_INITIALIZER __FAULT_ATTR_INITIALIZER(false) > + > +#define DECLARE_FAULT_ATTR(name) \ > + struct fault_attr name = __FAULT_ATTR_INITIALIZER(false) > +#define DECLARE_GLOBAL_FAULT_ATTR(name) \ > + struct fault_attr name = __FAULT_ATTR_INITIALIZER(true) > int setup_fault_attr(struct fault_attr *attr, char *str); > bool should_fail(struct fault_attr *attr, ssize_t size); > > diff --git a/lib/fault-inject.c b/lib/fault-inject.c > index 7d315fdb9f13..c8f6ef5df3c6 100644 > --- a/lib/fault-inject.c > +++ b/lib/fault-inject.c > @@ -107,7 +107,7 @@ static inline bool fail_stacktrace(struct fault_attr *attr) > > bool should_fail(struct fault_attr *attr, ssize_t size) > { > - if (in_task()) { > + if (!attr->global && in_task()) { > unsigned int fail_nth = READ_ONCE(current->fail_nth); > > if (fail_nth && !WRITE_ONCE(current->fail_nth, fail_nth - 1)) > @@ -224,6 +224,8 @@ struct dentry *fault_create_debugfs_attr(const char *name, > if (!debugfs_create_u32("verbose_ratelimit_burst", mode, dir, > &attr->ratelimit_state.burst)) > goto fail; > + if (!debugfs_create_bool("global", mode, dir, &attr->global)) > + goto fail; > if (!debugfs_create_bool("task-filter", mode, dir, &attr->task_filter)) > goto fail; > > -- > 2.14.0 >