12521f2c2SPeter Oberparleiter /* 22521f2c2SPeter Oberparleiter * This code maintains a list of active profiling data structures. 32521f2c2SPeter Oberparleiter * 42521f2c2SPeter Oberparleiter * Copyright IBM Corp. 2009 52521f2c2SPeter Oberparleiter * Author(s): Peter Oberparleiter <oberpar@linux.vnet.ibm.com> 62521f2c2SPeter Oberparleiter * 72521f2c2SPeter Oberparleiter * Uses gcc-internal data definitions. 82521f2c2SPeter Oberparleiter * Based on the gcov-kernel patch by: 92521f2c2SPeter Oberparleiter * Hubertus Franke <frankeh@us.ibm.com> 102521f2c2SPeter Oberparleiter * Nigel Hinds <nhinds@us.ibm.com> 112521f2c2SPeter Oberparleiter * Rajan Ravindran <rajancr@us.ibm.com> 122521f2c2SPeter Oberparleiter * Peter Oberparleiter <oberpar@linux.vnet.ibm.com> 132521f2c2SPeter Oberparleiter * Paul Larson 142521f2c2SPeter Oberparleiter */ 152521f2c2SPeter Oberparleiter 162521f2c2SPeter Oberparleiter #define pr_fmt(fmt) "gcov: " fmt 172521f2c2SPeter Oberparleiter 182521f2c2SPeter Oberparleiter #include <linux/init.h> 192521f2c2SPeter Oberparleiter #include <linux/module.h> 202521f2c2SPeter Oberparleiter #include <linux/mutex.h> 212521f2c2SPeter Oberparleiter #include "gcov.h" 222521f2c2SPeter Oberparleiter 232521f2c2SPeter Oberparleiter static int gcov_events_enabled; 242521f2c2SPeter Oberparleiter static DEFINE_MUTEX(gcov_lock); 252521f2c2SPeter Oberparleiter 262521f2c2SPeter Oberparleiter /* 272521f2c2SPeter Oberparleiter * __gcov_init is called by gcc-generated constructor code for each object 282521f2c2SPeter Oberparleiter * file compiled with -fprofile-arcs. 292521f2c2SPeter Oberparleiter */ 302521f2c2SPeter Oberparleiter void __gcov_init(struct gcov_info *info) 312521f2c2SPeter Oberparleiter { 322521f2c2SPeter Oberparleiter static unsigned int gcov_version; 332521f2c2SPeter Oberparleiter 342521f2c2SPeter Oberparleiter mutex_lock(&gcov_lock); 352521f2c2SPeter Oberparleiter if (gcov_version == 0) { 36*8cbce376SFrantisek Hrbata gcov_version = gcov_info_version(info); 372521f2c2SPeter Oberparleiter /* 382521f2c2SPeter Oberparleiter * Printing gcc's version magic may prove useful for debugging 392521f2c2SPeter Oberparleiter * incompatibility reports. 402521f2c2SPeter Oberparleiter */ 412521f2c2SPeter Oberparleiter pr_info("version magic: 0x%x\n", gcov_version); 422521f2c2SPeter Oberparleiter } 432521f2c2SPeter Oberparleiter /* 442521f2c2SPeter Oberparleiter * Add new profiling data structure to list and inform event 452521f2c2SPeter Oberparleiter * listener. 462521f2c2SPeter Oberparleiter */ 47*8cbce376SFrantisek Hrbata gcov_info_link(info); 482521f2c2SPeter Oberparleiter if (gcov_events_enabled) 492521f2c2SPeter Oberparleiter gcov_event(GCOV_ADD, info); 502521f2c2SPeter Oberparleiter mutex_unlock(&gcov_lock); 512521f2c2SPeter Oberparleiter } 522521f2c2SPeter Oberparleiter EXPORT_SYMBOL(__gcov_init); 532521f2c2SPeter Oberparleiter 542521f2c2SPeter Oberparleiter /* 552521f2c2SPeter Oberparleiter * These functions may be referenced by gcc-generated profiling code but serve 562521f2c2SPeter Oberparleiter * no function for kernel profiling. 572521f2c2SPeter Oberparleiter */ 582521f2c2SPeter Oberparleiter void __gcov_flush(void) 592521f2c2SPeter Oberparleiter { 602521f2c2SPeter Oberparleiter /* Unused. */ 612521f2c2SPeter Oberparleiter } 622521f2c2SPeter Oberparleiter EXPORT_SYMBOL(__gcov_flush); 632521f2c2SPeter Oberparleiter 642521f2c2SPeter Oberparleiter void __gcov_merge_add(gcov_type *counters, unsigned int n_counters) 652521f2c2SPeter Oberparleiter { 662521f2c2SPeter Oberparleiter /* Unused. */ 672521f2c2SPeter Oberparleiter } 682521f2c2SPeter Oberparleiter EXPORT_SYMBOL(__gcov_merge_add); 692521f2c2SPeter Oberparleiter 702521f2c2SPeter Oberparleiter void __gcov_merge_single(gcov_type *counters, unsigned int n_counters) 712521f2c2SPeter Oberparleiter { 722521f2c2SPeter Oberparleiter /* Unused. */ 732521f2c2SPeter Oberparleiter } 742521f2c2SPeter Oberparleiter EXPORT_SYMBOL(__gcov_merge_single); 752521f2c2SPeter Oberparleiter 762521f2c2SPeter Oberparleiter void __gcov_merge_delta(gcov_type *counters, unsigned int n_counters) 772521f2c2SPeter Oberparleiter { 782521f2c2SPeter Oberparleiter /* Unused. */ 792521f2c2SPeter Oberparleiter } 802521f2c2SPeter Oberparleiter EXPORT_SYMBOL(__gcov_merge_delta); 812521f2c2SPeter Oberparleiter 822521f2c2SPeter Oberparleiter /** 832521f2c2SPeter Oberparleiter * gcov_enable_events - enable event reporting through gcov_event() 842521f2c2SPeter Oberparleiter * 852521f2c2SPeter Oberparleiter * Turn on reporting of profiling data load/unload-events through the 862521f2c2SPeter Oberparleiter * gcov_event() callback. Also replay all previous events once. This function 872521f2c2SPeter Oberparleiter * is needed because some events are potentially generated too early for the 882521f2c2SPeter Oberparleiter * callback implementation to handle them initially. 892521f2c2SPeter Oberparleiter */ 902521f2c2SPeter Oberparleiter void gcov_enable_events(void) 912521f2c2SPeter Oberparleiter { 92*8cbce376SFrantisek Hrbata struct gcov_info *info = NULL; 932521f2c2SPeter Oberparleiter 942521f2c2SPeter Oberparleiter mutex_lock(&gcov_lock); 952521f2c2SPeter Oberparleiter gcov_events_enabled = 1; 96*8cbce376SFrantisek Hrbata 972521f2c2SPeter Oberparleiter /* Perform event callback for previously registered entries. */ 98*8cbce376SFrantisek Hrbata while ((info = gcov_info_next(info))) 992521f2c2SPeter Oberparleiter gcov_event(GCOV_ADD, info); 100*8cbce376SFrantisek Hrbata 1012521f2c2SPeter Oberparleiter mutex_unlock(&gcov_lock); 1022521f2c2SPeter Oberparleiter } 1032521f2c2SPeter Oberparleiter 1042521f2c2SPeter Oberparleiter #ifdef CONFIG_MODULES 1052521f2c2SPeter Oberparleiter static inline int within(void *addr, void *start, unsigned long size) 1062521f2c2SPeter Oberparleiter { 1072521f2c2SPeter Oberparleiter return ((addr >= start) && (addr < start + size)); 1082521f2c2SPeter Oberparleiter } 1092521f2c2SPeter Oberparleiter 1102521f2c2SPeter Oberparleiter /* Update list and generate events when modules are unloaded. */ 1112521f2c2SPeter Oberparleiter static int gcov_module_notifier(struct notifier_block *nb, unsigned long event, 1122521f2c2SPeter Oberparleiter void *data) 1132521f2c2SPeter Oberparleiter { 1142521f2c2SPeter Oberparleiter struct module *mod = data; 115*8cbce376SFrantisek Hrbata struct gcov_info *info = NULL; 116*8cbce376SFrantisek Hrbata struct gcov_info *prev = NULL; 1172521f2c2SPeter Oberparleiter 1182521f2c2SPeter Oberparleiter if (event != MODULE_STATE_GOING) 1192521f2c2SPeter Oberparleiter return NOTIFY_OK; 1202521f2c2SPeter Oberparleiter mutex_lock(&gcov_lock); 121*8cbce376SFrantisek Hrbata 1222521f2c2SPeter Oberparleiter /* Remove entries located in module from linked list. */ 123*8cbce376SFrantisek Hrbata while ((info = gcov_info_next(info))) { 1242521f2c2SPeter Oberparleiter if (within(info, mod->module_core, mod->core_size)) { 125*8cbce376SFrantisek Hrbata gcov_info_unlink(prev, info); 1262521f2c2SPeter Oberparleiter if (gcov_events_enabled) 1272521f2c2SPeter Oberparleiter gcov_event(GCOV_REMOVE, info); 1282521f2c2SPeter Oberparleiter } else 1292521f2c2SPeter Oberparleiter prev = info; 1302521f2c2SPeter Oberparleiter } 131*8cbce376SFrantisek Hrbata 1322521f2c2SPeter Oberparleiter mutex_unlock(&gcov_lock); 1332521f2c2SPeter Oberparleiter 1342521f2c2SPeter Oberparleiter return NOTIFY_OK; 1352521f2c2SPeter Oberparleiter } 1362521f2c2SPeter Oberparleiter 1372521f2c2SPeter Oberparleiter static struct notifier_block gcov_nb = { 1382521f2c2SPeter Oberparleiter .notifier_call = gcov_module_notifier, 1392521f2c2SPeter Oberparleiter }; 1402521f2c2SPeter Oberparleiter 1412521f2c2SPeter Oberparleiter static int __init gcov_init(void) 1422521f2c2SPeter Oberparleiter { 1432521f2c2SPeter Oberparleiter return register_module_notifier(&gcov_nb); 1442521f2c2SPeter Oberparleiter } 1452521f2c2SPeter Oberparleiter device_initcall(gcov_init); 1462521f2c2SPeter Oberparleiter #endif /* CONFIG_MODULES */ 147