| Message ID | 20170822230043.9968-2-bart.vanassche@wdc.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
2017-08-23 8:00 GMT+09:00 Bart Van Assche <bart.vanassche@wdc.com>: > 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 <bart.vanassche@wdc.com> > Cc: Dmitry Vyukov <dvyukov@google.com> > Cc: Akinobu Mita <akinobu.mita@gmail.com> > Cc: Michal Hocko <mhocko@kernel.org> > Cc: Andrew Morton <akpm@linux-foundation.org> > --- > 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 >
On Wed, Aug 23, 2017 at 2:10 AM, Akinobu Mita <akinobu.mita@gmail.com> wrote: > 2017-08-23 8:00 GMT+09:00 Bart Van Assche <bart.vanassche@wdc.com>: >> 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. Agree. Otherwise I don't understand this commit. We now have 2 orthogonal injection mechanisms: one global (original) and the new local. If one needs global injection, he/she just enables the global one. We don't seem to need the global flag on fault attributes. >> References: commit e41d58185f14 ("fault-inject: support systematic fault injection") >> Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com> >> Cc: Dmitry Vyukov <dvyukov@google.com> >> Cc: Akinobu Mita <akinobu.mita@gmail.com> >> Cc: Michal Hocko <mhocko@kernel.org> >> Cc: Andrew Morton <akpm@linux-foundation.org> >> --- >> 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 >>
On Wed, 2017-08-23 at 09:10 +0900, Akinobu Mita wrote: > 2017-08-23 8:00 GMT+09:00 Bart Van Assche <bart.vanassche@wdc.com>: > > 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. Hello Akinobu, Since I was using the block layer for-next branch as the basis of my tests, commit 9eeb52ae712e was not present in the kernel tree used in my tests. However, with that commit 9eeb52ae712e applied I don't need my two patches anymore to inject block layer timeout faults successfully. So I'm fine with dropping my two patches. Sorry for the noise. Bart.
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;
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'. References: commit e41d58185f14 ("fault-inject: support systematic fault injection") Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Akinobu Mita <akinobu.mita@gmail.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> --- include/linux/fault-inject.h | 11 +++++++++-- lib/fault-inject.c | 4 +++- 2 files changed, 12 insertions(+), 3 deletions(-)