From 871480933a1c28f8a9fed4c4d34d06c439a7a422 Mon Sep 17 00:00:00 2001 From: Srikant Patnaik Date: Sun, 11 Jan 2015 12:28:04 +0530 Subject: Moved, renamed, and deleted files The original directory structure was scattered and unorganized. Changes are basically to make it look like kernel structure. --- lib/smp_processor_id.c | 55 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 55 insertions(+) create mode 100644 lib/smp_processor_id.c (limited to 'lib/smp_processor_id.c') diff --git a/lib/smp_processor_id.c b/lib/smp_processor_id.c new file mode 100644 index 00000000..4c0d0e51 --- /dev/null +++ b/lib/smp_processor_id.c @@ -0,0 +1,55 @@ +/* + * lib/smp_processor_id.c + * + * DEBUG_PREEMPT variant of smp_processor_id(). + */ +#include +#include +#include + +notrace unsigned int debug_smp_processor_id(void) +{ + unsigned long preempt_count = preempt_count(); + int this_cpu = raw_smp_processor_id(); + + if (likely(preempt_count)) + goto out; + + if (irqs_disabled()) + goto out; + + /* + * Kernel threads bound to a single CPU can safely use + * smp_processor_id(): + */ + if (cpumask_equal(tsk_cpus_allowed(current), cpumask_of(this_cpu))) + goto out; + + /* + * It is valid to assume CPU-locality during early bootup: + */ + if (system_state != SYSTEM_RUNNING) + goto out; + + /* + * Avoid recursion: + */ + preempt_disable_notrace(); + + 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_notrace(); +out: + return this_cpu; +} + +EXPORT_SYMBOL(debug_smp_processor_id); + -- cgit