VisionFive2 Linux kernel

b24413180f560 (Greg Kroah-Hartman 2017-11-01 15:07:57 +0100  1) // SPDX-License-Identifier: GPL-2.0
39c715b71740c (Ingo Molnar        2005-06-21 17:14:34 -0700  2) /*
39c715b71740c (Ingo Molnar        2005-06-21 17:14:34 -0700  3)  * lib/smp_processor_id.c
39c715b71740c (Ingo Molnar        2005-06-21 17:14:34 -0700  4)  *
39c715b71740c (Ingo Molnar        2005-06-21 17:14:34 -0700  5)  * DEBUG_PREEMPT variant of smp_processor_id().
39c715b71740c (Ingo Molnar        2005-06-21 17:14:34 -0700  6)  */
8bc3bcc93a2b4 (Paul Gortmaker     2011-11-16 21:29:17 -0500  7) #include <linux/export.h>
984640ce427fa (Masami Hiramatsu   2019-02-13 01:14:09 +0900  8) #include <linux/kprobes.h>
4e57b68178809 (Tim Schmielau      2005-10-30 15:03:48 -0800  9) #include <linux/sched.h>
39c715b71740c (Ingo Molnar        2005-06-21 17:14:34 -0700 10) 
126f21f0e8d46 (Thomas Gleixner    2020-03-10 23:47:39 +0100 11) noinstr static
984640ce427fa (Masami Hiramatsu   2019-02-13 01:14:09 +0900 12) unsigned int check_preemption_disabled(const char *what1, const char *what2)
39c715b71740c (Ingo Molnar        2005-06-21 17:14:34 -0700 13) {
39c715b71740c (Ingo Molnar        2005-06-21 17:14:34 -0700 14) 	int this_cpu = raw_smp_processor_id();
39c715b71740c (Ingo Molnar        2005-06-21 17:14:34 -0700 15) 
4a2b4b222743b (Peter Zijlstra     2013-08-14 14:55:24 +0200 16) 	if (likely(preempt_count()))
39c715b71740c (Ingo Molnar        2005-06-21 17:14:34 -0700 17) 		goto out;
39c715b71740c (Ingo Molnar        2005-06-21 17:14:34 -0700 18) 
39c715b71740c (Ingo Molnar        2005-06-21 17:14:34 -0700 19) 	if (irqs_disabled())
39c715b71740c (Ingo Molnar        2005-06-21 17:14:34 -0700 20) 		goto out;
39c715b71740c (Ingo Molnar        2005-06-21 17:14:34 -0700 21) 
39c715b71740c (Ingo Molnar        2005-06-21 17:14:34 -0700 22) 	/*
39c715b71740c (Ingo Molnar        2005-06-21 17:14:34 -0700 23) 	 * Kernel threads bound to a single CPU can safely use
39c715b71740c (Ingo Molnar        2005-06-21 17:14:34 -0700 24) 	 * smp_processor_id():
39c715b71740c (Ingo Molnar        2005-06-21 17:14:34 -0700 25) 	 */
e950cca3f3c40 (Waiman Long        2019-10-03 16:36:08 -0400 26) 	if (current->nr_cpus_allowed == 1)
39c715b71740c (Ingo Molnar        2005-06-21 17:14:34 -0700 27) 		goto out;
39c715b71740c (Ingo Molnar        2005-06-21 17:14:34 -0700 28) 
74d862b682f51 (Thomas Gleixner    2020-11-18 20:48:42 +0100 29) #ifdef CONFIG_SMP
af449901b84c9 (Peter Zijlstra     2020-09-17 10:38:30 +0200 30) 	if (current->migration_disabled)
af449901b84c9 (Peter Zijlstra     2020-09-17 10:38:30 +0200 31) 		goto out;
af449901b84c9 (Peter Zijlstra     2020-09-17 10:38:30 +0200 32) #endif
af449901b84c9 (Peter Zijlstra     2020-09-17 10:38:30 +0200 33) 
39c715b71740c (Ingo Molnar        2005-06-21 17:14:34 -0700 34) 	/*
39c715b71740c (Ingo Molnar        2005-06-21 17:14:34 -0700 35) 	 * It is valid to assume CPU-locality during early bootup:
39c715b71740c (Ingo Molnar        2005-06-21 17:14:34 -0700 36) 	 */
1c3c5eab17159 (Thomas Gleixner    2017-05-16 20:42:48 +0200 37) 	if (system_state < SYSTEM_SCHEDULING)
39c715b71740c (Ingo Molnar        2005-06-21 17:14:34 -0700 38) 		goto out;
39c715b71740c (Ingo Molnar        2005-06-21 17:14:34 -0700 39) 
39c715b71740c (Ingo Molnar        2005-06-21 17:14:34 -0700 40) 	/*
39c715b71740c (Ingo Molnar        2005-06-21 17:14:34 -0700 41) 	 * Avoid recursion:
39c715b71740c (Ingo Molnar        2005-06-21 17:14:34 -0700 42) 	 */
5568b139f4d19 (Steven Rostedt     2008-05-12 21:20:44 +0200 43) 	preempt_disable_notrace();
39c715b71740c (Ingo Molnar        2005-06-21 17:14:34 -0700 44) 
126f21f0e8d46 (Thomas Gleixner    2020-03-10 23:47:39 +0100 45) 	instrumentation_begin();
39c715b71740c (Ingo Molnar        2005-06-21 17:14:34 -0700 46) 	if (!printk_ratelimit())
39c715b71740c (Ingo Molnar        2005-06-21 17:14:34 -0700 47) 		goto out_enable;
39c715b71740c (Ingo Molnar        2005-06-21 17:14:34 -0700 48) 
188a81409ff7d (Christoph Lameter  2014-04-07 15:39:44 -0700 49) 	printk(KERN_ERR "BUG: using %s%s() in preemptible [%08x] code: %s/%d\n",
188a81409ff7d (Christoph Lameter  2014-04-07 15:39:44 -0700 50) 		what1, what2, preempt_count() - 1, current->comm, current->pid);
188a81409ff7d (Christoph Lameter  2014-04-07 15:39:44 -0700 51) 
d202d47b5e62c (Sergey Senozhatsky 2017-12-11 21:50:24 +0900 52) 	printk("caller is %pS\n", __builtin_return_address(0));
39c715b71740c (Ingo Molnar        2005-06-21 17:14:34 -0700 53) 	dump_stack();
126f21f0e8d46 (Thomas Gleixner    2020-03-10 23:47:39 +0100 54) 	instrumentation_end();
39c715b71740c (Ingo Molnar        2005-06-21 17:14:34 -0700 55) 
39c715b71740c (Ingo Molnar        2005-06-21 17:14:34 -0700 56) out_enable:
5568b139f4d19 (Steven Rostedt     2008-05-12 21:20:44 +0200 57) 	preempt_enable_no_resched_notrace();
39c715b71740c (Ingo Molnar        2005-06-21 17:14:34 -0700 58) out:
39c715b71740c (Ingo Molnar        2005-06-21 17:14:34 -0700 59) 	return this_cpu;
39c715b71740c (Ingo Molnar        2005-06-21 17:14:34 -0700 60) }
39c715b71740c (Ingo Molnar        2005-06-21 17:14:34 -0700 61) 
126f21f0e8d46 (Thomas Gleixner    2020-03-10 23:47:39 +0100 62) noinstr unsigned int debug_smp_processor_id(void)
188a81409ff7d (Christoph Lameter  2014-04-07 15:39:44 -0700 63) {
188a81409ff7d (Christoph Lameter  2014-04-07 15:39:44 -0700 64) 	return check_preemption_disabled("smp_processor_id", "");
188a81409ff7d (Christoph Lameter  2014-04-07 15:39:44 -0700 65) }
39c715b71740c (Ingo Molnar        2005-06-21 17:14:34 -0700 66) EXPORT_SYMBOL(debug_smp_processor_id);
39c715b71740c (Ingo Molnar        2005-06-21 17:14:34 -0700 67) 
126f21f0e8d46 (Thomas Gleixner    2020-03-10 23:47:39 +0100 68) noinstr void __this_cpu_preempt_check(const char *op)
188a81409ff7d (Christoph Lameter  2014-04-07 15:39:44 -0700 69) {
188a81409ff7d (Christoph Lameter  2014-04-07 15:39:44 -0700 70) 	check_preemption_disabled("__this_cpu_", op);
188a81409ff7d (Christoph Lameter  2014-04-07 15:39:44 -0700 71) }
188a81409ff7d (Christoph Lameter  2014-04-07 15:39:44 -0700 72) EXPORT_SYMBOL(__this_cpu_preempt_check);