From 7b3c92b85a65c2db1f542265bc98e1f9e3056eba Mon Sep 17 00:00:00 2001 From: "Matthew Wilcox (Oracle)" Date: Thu, 4 Jul 2019 15:13:23 -0700 Subject: sched/core: Convert get_task_struct() to return the task Returning the pointer that was passed in allows us to write slightly more idiomatic code. Convert a few users. Signed-off-by: Matthew Wilcox (Oracle) Signed-off-by: Peter Zijlstra (Intel) Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Link: https://lkml.kernel.org/r/20190704221323.24290-1-willy@infradead.org Signed-off-by: Ingo Molnar --- include/linux/sched/task.h | 6 +++++- kernel/events/core.c | 9 +++------ kernel/irq/manage.c | 3 +-- kernel/locking/rtmutex.c | 6 ++---- kernel/trace/trace_sched_wakeup.c | 3 +-- 5 files changed, 12 insertions(+), 15 deletions(-) diff --git a/include/linux/sched/task.h b/include/linux/sched/task.h index 0497091e40c1..3d90ed8f75f0 100644 --- a/include/linux/sched/task.h +++ b/include/linux/sched/task.h @@ -105,7 +105,11 @@ extern void sched_exec(void); #define sched_exec() {} #endif -#define get_task_struct(tsk) do { refcount_inc(&(tsk)->usage); } while(0) +static inline struct task_struct *get_task_struct(struct task_struct *t) +{ + refcount_inc(&t->usage); + return t; +} extern void __put_task_struct(struct task_struct *t); diff --git a/kernel/events/core.c b/kernel/events/core.c index 026a14541a38..ea5e8139fe62 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -4089,10 +4089,8 @@ alloc_perf_context(struct pmu *pmu, struct task_struct *task) return NULL; __perf_event_init_context(ctx); - if (task) { - ctx->task = task; - get_task_struct(task); - } + if (task) + ctx->task = get_task_struct(task); ctx->pmu = pmu; return ctx; @@ -10355,8 +10353,7 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu, * and we cannot use the ctx information because we need the * pmu before we get a ctx. */ - get_task_struct(task); - event->hw.target = task; + event->hw.target = get_task_struct(task); } event->clock = &local_clock; diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c index e8f7f179bf77..9d50fbe5531a 100644 --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -1255,8 +1255,7 @@ setup_irq_thread(struct irqaction *new, unsigned int irq, bool secondary) * the thread dies to avoid that the interrupt code * references an already freed task_struct. */ - get_task_struct(t); - new->thread = t; + new->thread = get_task_struct(t); /* * Tell the thread to set its affinity. This is * important for shared interrupt handlers as we do diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c index fa83d36e30c6..2874bf556162 100644 --- a/kernel/locking/rtmutex.c +++ b/kernel/locking/rtmutex.c @@ -628,8 +628,7 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task, } /* [10] Grab the next task, i.e. owner of @lock */ - task = rt_mutex_owner(lock); - get_task_struct(task); + task = get_task_struct(rt_mutex_owner(lock)); raw_spin_lock(&task->pi_lock); /* @@ -709,8 +708,7 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task, } /* [10] Grab the next task, i.e. the owner of @lock */ - task = rt_mutex_owner(lock); - get_task_struct(task); + task = get_task_struct(rt_mutex_owner(lock)); raw_spin_lock(&task->pi_lock); /* [11] requeue the pi waiters if necessary */ diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c index 743b2b520d34..5e43b9664eca 100644 --- a/kernel/trace/trace_sched_wakeup.c +++ b/kernel/trace/trace_sched_wakeup.c @@ -579,8 +579,7 @@ probe_wakeup(void *ignore, struct task_struct *p) else tracing_dl = 0; - wakeup_task = p; - get_task_struct(wakeup_task); + wakeup_task = get_task_struct(p); local_save_flags(flags); -- cgit