sched/stat: Simplify the sched_info accounting dependency Both CONFIG_SCHEDSTATS=y and CONFIG_TASK_DELAY_ACCT=y track task sched_info, which results in ugly #if clauses. Simplify the code by introducing a synthethic CONFIG_SCHED_INFO switch, selected by both. Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Cc: Balbir Singh <bsingharora@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: a.p.zijlstra@chello.nl Cc: ricklind@us.ibm.com Link: http://lkml.kernel.org/r/8d19eef800811a94b0f91bcbeb27430a884d7433.1435255405.git.naveen.n.rao@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
diff --git a/include/linux/sched.h b/include/linux/sched.h index 6633e83..9bf4bc0 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h
@@ -849,7 +849,7 @@ struct backing_dev_info; struct reclaim_state; -#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) +#ifdef CONFIG_SCHED_INFO struct sched_info { /* cumulative counters */ unsigned long pcount; /* # of times run on this cpu */ @@ -859,7 +859,7 @@ unsigned long long last_arrival,/* when we last ran on a cpu */ last_queued; /* when we were last queued to run */ }; -#endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */ +#endif /* CONFIG_SCHED_INFO */ #ifdef CONFIG_TASK_DELAY_ACCT struct task_delay_info { @@ -1408,7 +1408,7 @@ int rcu_tasks_idle_cpu; #endif /* #ifdef CONFIG_TASKS_RCU */ -#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) +#ifdef CONFIG_SCHED_INFO struct sched_info sched_info; #endif
diff --git a/init/Kconfig b/init/Kconfig index b999fa3..12cb556 100644 --- a/init/Kconfig +++ b/init/Kconfig
@@ -435,6 +435,7 @@ config TASK_DELAY_ACCT bool "Enable per-task delay accounting" depends on TASKSTATS + select SCHED_INFO help Collect information on time spent by a task waiting for system resources like cpu, synchronous block I/O completion and swapping
diff --git a/kernel/sched/core.c b/kernel/sched/core.c index c86935a..abb8785 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c
@@ -1975,7 +1975,7 @@ set_task_cpu(p, cpu); raw_spin_unlock_irqrestore(&p->pi_lock, flags); -#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) +#ifdef CONFIG_SCHED_INFO if (likely(sched_info_on())) memset(&p->sched_info, 0, sizeof(p->sched_info)); #endif
diff --git a/kernel/sched/stats.h b/kernel/sched/stats.h index 077ebbd..b0fbc76 100644 --- a/kernel/sched/stats.h +++ b/kernel/sched/stats.h
@@ -47,7 +47,7 @@ # define schedstat_set(var, val) do { } while (0) #endif -#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) +#ifdef CONFIG_SCHED_INFO static inline void sched_info_reset_dequeued(struct task_struct *t) { t->sched_info.last_queued = 0; @@ -156,7 +156,7 @@ #define sched_info_depart(rq, t) do { } while (0) #define sched_info_arrive(rq, next) do { } while (0) #define sched_info_switch(rq, t, next) do { } while (0) -#endif /* CONFIG_SCHEDSTATS || CONFIG_TASK_DELAY_ACCT */ +#endif /* CONFIG_SCHED_INFO */ /* * The following are functions that support scheduler-internal time accounting.
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index b908048..e2894b2 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug
@@ -841,9 +841,14 @@ that can help debug the scheduler. The runtime overhead of this option is minimal. +config SCHED_INFO + bool + default n + config SCHEDSTATS bool "Collect scheduler statistics" depends on DEBUG_KERNEL && PROC_FS + select SCHED_INFO help If you say Y here, additional code will be inserted into the scheduler and related routines to collect statistics about