| Message ID | 20190729154657.31997-1-gabriel.pollo-guilbert@efficios.com |
|---|---|
| State | Superseded, archived |
| Headers | show |
| Series | [RFC,lttng-modules] Fix: update sched prev_state instrumentation for kernel 4.14.0 and 4.20.0 | expand |
----- On Jul 29, 2019, at 11:46 AM, Gabriel-Andrew Pollo-Guilbert gabriel.pollo-guilbert at efficios.com wrote: > Upstream Linux kernel commit in 4.14.0: > > commit efb40f588b4370ffaeffafbd50f6ff213d954254 > Author: Peter Zijlstra <peterz at infradead.org> > Date: Fri Sep 22 18:19:53 2017 +0200 > > sched/tracing: Fix trace_sched_switch task-state printing > > commit 3f5fe9fef5b2da06b6319fab8123056da5217c3f > Author: Thomas Gleixner <tglx at linutronix.de> > Date: Wed Nov 22 13:05:48 2017 +0100 > > sched/debug: Fix task state recording/printout > > Upstream Linux kernel commit in 4.20.0: > > commit 3054426dc68e5d63aa6a6e9b91ac4ec78e3f3805 > Author: Pavankumar Kondeti <pkondeti at codeaurora.org> > Date: Tue Oct 30 12:24:33 2018 +0530 > > sched, trace: Fix prev_state output in sched_switch tracepoint > > Signed-off-by: Gabriel-Andrew Pollo-Guilbert > <gabriel.pollo-guilbert at efficios.com> > --- > instrumentation/events/lttng-module/sched.h | 47 ++++++++++++++++++++- > 1 file changed, 46 insertions(+), 1 deletion(-) > > diff --git a/instrumentation/events/lttng-module/sched.h > b/instrumentation/events/lttng-module/sched.h > index 77d77b2..f27cee5 100644 > --- a/instrumentation/events/lttng-module/sched.h > +++ b/instrumentation/events/lttng-module/sched.h > @@ -25,7 +25,52 @@ > #ifndef _TRACE_SCHED_DEF_ > #define _TRACE_SCHED_DEF_ > > -#if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,4,0)) > +#if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,20,0)) You need to check where the fixes were cherry-picked into respective stable branches. And if a Linux fix tackles a trace-event issue for a given kernel version (e.g. 4.14.0) without changing the internal kernel APIs available for modules, we need to cover that version (and possibly earlier versions) for that range in lttng-modules. For instance, v4.14.109 has: /* * Preemption ignores task state, therefore preempted tasks are always * RUNNING (we will not have dequeued if state != RUNNING). */ if (preempt) return TASK_REPORT_MAX; /* * task_state_index() uses fls() and returns a value from 0-8 range. * Decrement it by 1 (except TASK_RUNNING state i.e 0) before using * it for left shift operation to get the correct task->state * mapping. */ state = __get_task_state(p); return state ? (1 << (state - 1)) : state; But lttng-modules in this patch still has broken code for that kernel version. Thanks, Mathieu > + > +static inline long __trace_sched_switch_state(bool preempt, struct task_struct > *p) > +{ > + unsigned int state; > + > +#ifdef CONFIG_SCHED_DEBUG > + BUG_ON(p != current); > +#endif /* CONFIG_SCHED_DEBUG */ > + > + /* > + * Preemption ignores task state, therefore preempted tasks are always > + * RUNNING (we will not have dequeued if state != RUNNING). > + */ > + if (preempt) > + return TASK_REPORT_MAX; > + > + /* > + * task_state_index() uses fls() and returns a value from 0-8 range. > + * Decrement it by 1 (except TASK_RUNNING state i.e 0) before using > + * it for left shift operation to get the correct task->state > + * mapping. > + */ > + state = task_state_index(p); > + > + return state ? (1 << (state - 1)) : state; > +} > + > +#elif (LINUX_VERSION_CODE >= KERNEL_VERSION(4,14,0)) > + > +static inline long __trace_sched_switch_state(bool preempt, struct task_struct > *p) > +{ > +#ifdef CONFIG_SCHED_DEBUG > + BUG_ON(p != current); > +#endif /* CONFIG_SCHED_DEBUG */ > + /* > + * Preemption ignores task state, therefore preempted tasks are always RUNNING > + * (we will not have dequeued if state != RUNNING). > + */ > + if (preempt) > + return TASK_REPORT_MAX; > + > + return 1 << task_state_index(p); > +} > + > +#elif (LINUX_VERSION_CODE >= KERNEL_VERSION(4,4,0)) > > static inline long __trace_sched_switch_state(bool preempt, struct task_struct > *p) > { > -- > 2.22.0
diff --git a/instrumentation/events/lttng-module/sched.h b/instrumentation/events/lttng-module/sched.h index 77d77b2..f27cee5 100644 --- a/instrumentation/events/lttng-module/sched.h +++ b/instrumentation/events/lttng-module/sched.h @@ -25,7 +25,52 @@ #ifndef _TRACE_SCHED_DEF_ #define _TRACE_SCHED_DEF_ -#if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,4,0)) +#if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,20,0)) + +static inline long __trace_sched_switch_state(bool preempt, struct task_struct *p) +{ + unsigned int state; + +#ifdef CONFIG_SCHED_DEBUG + BUG_ON(p != current); +#endif /* CONFIG_SCHED_DEBUG */ + + /* + * Preemption ignores task state, therefore preempted tasks are always + * RUNNING (we will not have dequeued if state != RUNNING). + */ + if (preempt) + return TASK_REPORT_MAX; + + /* + * task_state_index() uses fls() and returns a value from 0-8 range. + * Decrement it by 1 (except TASK_RUNNING state i.e 0) before using + * it for left shift operation to get the correct task->state + * mapping. + */ + state = task_state_index(p); + + return state ? (1 << (state - 1)) : state; +} + +#elif (LINUX_VERSION_CODE >= KERNEL_VERSION(4,14,0)) + +static inline long __trace_sched_switch_state(bool preempt, struct task_struct *p) +{ +#ifdef CONFIG_SCHED_DEBUG + BUG_ON(p != current); +#endif /* CONFIG_SCHED_DEBUG */ + /* + * Preemption ignores task state, therefore preempted tasks are always RUNNING + * (we will not have dequeued if state != RUNNING). + */ + if (preempt) + return TASK_REPORT_MAX; + + return 1 << task_state_index(p); +} + +#elif (LINUX_VERSION_CODE >= KERNEL_VERSION(4,4,0)) static inline long __trace_sched_switch_state(bool preempt, struct task_struct *p) {
Upstream Linux kernel commit in 4.14.0: commit efb40f588b4370ffaeffafbd50f6ff213d954254 Author: Peter Zijlstra <peterz at infradead.org> Date: Fri Sep 22 18:19:53 2017 +0200 sched/tracing: Fix trace_sched_switch task-state printing commit 3f5fe9fef5b2da06b6319fab8123056da5217c3f Author: Thomas Gleixner <tglx at linutronix.de> Date: Wed Nov 22 13:05:48 2017 +0100 sched/debug: Fix task state recording/printout Upstream Linux kernel commit in 4.20.0: commit 3054426dc68e5d63aa6a6e9b91ac4ec78e3f3805 Author: Pavankumar Kondeti <pkondeti at codeaurora.org> Date: Tue Oct 30 12:24:33 2018 +0530 sched, trace: Fix prev_state output in sched_switch tracepoint Signed-off-by: Gabriel-Andrew Pollo-Guilbert <gabriel.pollo-guilbert at efficios.com> --- instrumentation/events/lttng-module/sched.h | 47 ++++++++++++++++++++- 1 file changed, 46 insertions(+), 1 deletion(-)