bd27acaac2
Currently instrumentation_end() won't be called if printk_ratelimit()
returned false.
Link: https://lkml.kernel.org/r/a636d8e0-ad32-5888-acac-671f7f553bb3@I-love.SAKURA.ne.jp
Fixes: 126f21f0e8 ("lib/smp_processor_id: Move it into noinstr section")
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Alexandre Chartre <alexandre.chartre@oracle.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
69 lines
1.4 KiB
C
69 lines
1.4 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* lib/smp_processor_id.c
|
|
*
|
|
* DEBUG_PREEMPT variant of smp_processor_id().
|
|
*/
|
|
#include <linux/export.h>
|
|
#include <linux/kprobes.h>
|
|
#include <linux/sched.h>
|
|
|
|
noinstr static
|
|
unsigned int check_preemption_disabled(const char *what1, const char *what2)
|
|
{
|
|
int this_cpu = raw_smp_processor_id();
|
|
|
|
if (likely(preempt_count()))
|
|
goto out;
|
|
|
|
if (irqs_disabled())
|
|
goto out;
|
|
|
|
if (is_percpu_thread())
|
|
goto out;
|
|
|
|
#ifdef CONFIG_SMP
|
|
if (current->migration_disabled)
|
|
goto out;
|
|
#endif
|
|
|
|
/*
|
|
* It is valid to assume CPU-locality during early bootup:
|
|
*/
|
|
if (system_state < SYSTEM_SCHEDULING)
|
|
goto out;
|
|
|
|
/*
|
|
* Avoid recursion:
|
|
*/
|
|
preempt_disable_notrace();
|
|
|
|
instrumentation_begin();
|
|
if (!printk_ratelimit())
|
|
goto out_enable;
|
|
|
|
printk(KERN_ERR "BUG: using %s%s() in preemptible [%08x] code: %s/%d\n",
|
|
what1, what2, preempt_count() - 1, current->comm, current->pid);
|
|
|
|
printk("caller is %pS\n", __builtin_return_address(0));
|
|
dump_stack();
|
|
|
|
out_enable:
|
|
instrumentation_end();
|
|
preempt_enable_no_resched_notrace();
|
|
out:
|
|
return this_cpu;
|
|
}
|
|
|
|
noinstr unsigned int debug_smp_processor_id(void)
|
|
{
|
|
return check_preemption_disabled("smp_processor_id", "");
|
|
}
|
|
EXPORT_SYMBOL(debug_smp_processor_id);
|
|
|
|
noinstr void __this_cpu_preempt_check(const char *op)
|
|
{
|
|
check_preemption_disabled("__this_cpu_", op);
|
|
}
|
|
EXPORT_SYMBOL(__this_cpu_preempt_check);
|