From f6db8347993256b58bd4746b0c4c5b935c32210d Mon Sep 17 00:00:00 2001 From: "Naveen N. Rao" Date: Thu, 25 Jun 2015 23:53:37 +0530 Subject: [PATCH] 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 Cc: Balbir Singh Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Srikar Dronamraju Cc: Thomas Gleixner 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 --- include/linux/sched.h | 6 +++--- init/Kconfig | 1 + kernel/sched/core.c | 2 +- kernel/sched/stats.h | 4 ++-- lib/Kconfig.debug | 5 +++++ 5 files changed, 12 insertions(+), 6 deletions(-) diff --git a/include/linux/sched.h b/include/linux/sched.h index 6633e83e608a..9bf4bc0e3b8b 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -849,7 +849,7 @@ extern struct user_struct root_user; 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 @@ struct sched_info { 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 @@ struct task_struct { 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 b999fa381bf9..12cb556ad160 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -435,6 +435,7 @@ config TASKSTATS 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 c86935a7f1f8..abb8785ed1ba 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -1975,7 +1975,7 @@ int sched_fork(unsigned long clone_flags, struct task_struct *p) 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 077ebbd5e10f..b0fbc7632de5 100644 --- a/kernel/sched/stats.h +++ b/kernel/sched/stats.h @@ -47,7 +47,7 @@ rq_sched_info_depart(struct rq *rq, unsigned long long delta) # 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 @@ sched_info_switch(struct rq *rq, #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 b908048f8d6a..e2894b23efb6 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -841,9 +841,14 @@ config SCHED_DEBUG 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