linux_dsm_epyc7002/lib/smp_processor_id.c
Arnaldo Carvalho de Melo 6e766410c4 ftrace: annotate core code that should not be traced
Mark with "notrace" functions in core code that should not be
traced.  The "notrace" attribute will prevent gcc from adding
a call to ftrace on the annotated funtions.

Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-23 20:31:48 +02:00

59 lines
1.1 KiB
C

/*
* lib/smp_processor_id.c
*
* DEBUG_PREEMPT variant of smp_processor_id().
*/
#include <linux/module.h>
#include <linux/kallsyms.h>
#include <linux/sched.h>
notrace unsigned int debug_smp_processor_id(void)
{
unsigned long preempt_count = preempt_count();
int this_cpu = raw_smp_processor_id();
cpumask_t this_mask;
if (likely(preempt_count))
goto out;
if (irqs_disabled())
goto out;
/*
* Kernel threads bound to a single CPU can safely use
* smp_processor_id():
*/
this_mask = cpumask_of_cpu(this_cpu);
if (cpus_equal(current->cpus_allowed, this_mask))
goto out;
/*
* It is valid to assume CPU-locality during early bootup:
*/
if (system_state != SYSTEM_RUNNING)
goto out;
/*
* Avoid recursion:
*/
preempt_disable();
if (!printk_ratelimit())
goto out_enable;
printk(KERN_ERR "BUG: using smp_processor_id() in preemptible [%08x] "
"code: %s/%d\n",
preempt_count() - 1, current->comm, current->pid);
print_symbol("caller is %s\n", (long)__builtin_return_address(0));
dump_stack();
out_enable:
preempt_enable_no_resched();
out:
return this_cpu;
}
EXPORT_SYMBOL(debug_smp_processor_id);