leandrof/linux
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

rcu: Always inline rcu_dynticks_task*_{enter,exit}()

Browse Source 
RCU managed to grow a few noinstr violations:

  vmlinux.o: warning: objtool: rcu_dynticks_eqs_enter()+0x0: call to rcu_dynticks_task_trace_enter() leaves .noinstr.text section
  vmlinux.o: warning: objtool: rcu_dynticks_eqs_exit()+0xe: call to rcu_dynticks_task_trace_exit() leaves .noinstr.text section

Fix them by adding __always_inline to the relevant trivial functions.

Also replace the noinstr with __always_inline for the existing
rcu_dynticks_task_*() functions since noinstr would force noinline
them, even when empty, which seems silly.

Fixes: 7d0c9c50c5 ("rcu-tasks: Avoid IPIing userspace/idle tasks if kernel is so built")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit is contained in:
Peter Zijlstra 2021-09-28 10:40:21 +02:00 committed by Paul E. McKenney
parent 925da92ba5
commit 7663ad9a5d
1 changed files with 4 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
kernel/rcu/tree_plugin.h
View File

@ -1479,7 +1479,7 @@ static void rcu_bind_gp_kthread(void)
}
/* Record the current task on dyntick-idle entry. */
static void noinstr rcu_dynticks_task_enter(void)
static __always_inline void rcu_dynticks_task_enter(void)
{
#if defined(CONFIG_TASKS_RCU) && defined(CONFIG_NO_HZ_FULL)
WRITE_ONCE(current->rcu_tasks_idle_cpu, smp_processor_id());
@ -1487,7 +1487,7 @@ static void noinstr rcu_dynticks_task_enter(void)
}
/* Record no current task on dyntick-idle exit. */
static void noinstr rcu_dynticks_task_exit(void)
static __always_inline void rcu_dynticks_task_exit(void)
{
#if defined(CONFIG_TASKS_RCU) && defined(CONFIG_NO_HZ_FULL)
WRITE_ONCE(current->rcu_tasks_idle_cpu, -1);
@ -1495,7 +1495,7 @@ static void noinstr rcu_dynticks_task_exit(void)
}
/* Turn on heavyweight RCU tasks trace readers on idle/user entry. */
static void rcu_dynticks_task_trace_enter(void)
static __always_inline void rcu_dynticks_task_trace_enter(void)
{
#ifdef CONFIG_TASKS_TRACE_RCU
if (IS_ENABLED(CONFIG_TASKS_TRACE_RCU_READ_MB))
@ -1504,7 +1504,7 @@ static void rcu_dynticks_task_trace_enter(void)
}
/* Turn off heavyweight RCU tasks trace readers on idle/user exit. */
static void rcu_dynticks_task_trace_exit(void)
static __always_inline void rcu_dynticks_task_trace_exit(void)
{
#ifdef CONFIG_TASKS_TRACE_RCU
if (IS_ENABLED(CONFIG_TASKS_TRACE_RCU_READ_MB))