1b2441318SGreg Kroah-Hartman // SPDX-License-Identifier: GPL-2.0
22521f2c2SPeter Oberparleiter /*
32521f2c2SPeter Oberparleiter * This code maintains a list of active profiling data structures.
42521f2c2SPeter Oberparleiter *
52521f2c2SPeter Oberparleiter * Copyright IBM Corp. 2009
62521f2c2SPeter Oberparleiter * Author(s): Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
72521f2c2SPeter Oberparleiter *
82521f2c2SPeter Oberparleiter * Uses gcc-internal data definitions.
92521f2c2SPeter Oberparleiter * Based on the gcov-kernel patch by:
102521f2c2SPeter Oberparleiter * Hubertus Franke <frankeh@us.ibm.com>
112521f2c2SPeter Oberparleiter * Nigel Hinds <nhinds@us.ibm.com>
122521f2c2SPeter Oberparleiter * Rajan Ravindran <rajancr@us.ibm.com>
132521f2c2SPeter Oberparleiter * Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
142521f2c2SPeter Oberparleiter * Paul Larson
152521f2c2SPeter Oberparleiter */
162521f2c2SPeter Oberparleiter
172521f2c2SPeter Oberparleiter #define pr_fmt(fmt) "gcov: " fmt
182521f2c2SPeter Oberparleiter
192521f2c2SPeter Oberparleiter #include <linux/init.h>
202521f2c2SPeter Oberparleiter #include <linux/module.h>
212521f2c2SPeter Oberparleiter #include <linux/mutex.h>
229d796e66SAndrey Ryabinin #include <linux/sched.h>
232521f2c2SPeter Oberparleiter #include "gcov.h"
242521f2c2SPeter Oberparleiter
25826eba0dSGreg Hackmann int gcov_events_enabled;
26826eba0dSGreg Hackmann DEFINE_MUTEX(gcov_lock);
2705384213SMartin Liska
282521f2c2SPeter Oberparleiter /**
292521f2c2SPeter Oberparleiter * gcov_enable_events - enable event reporting through gcov_event()
302521f2c2SPeter Oberparleiter *
312521f2c2SPeter Oberparleiter * Turn on reporting of profiling data load/unload-events through the
322521f2c2SPeter Oberparleiter * gcov_event() callback. Also replay all previous events once. This function
332521f2c2SPeter Oberparleiter * is needed because some events are potentially generated too early for the
342521f2c2SPeter Oberparleiter * callback implementation to handle them initially.
352521f2c2SPeter Oberparleiter */
gcov_enable_events(void)362521f2c2SPeter Oberparleiter void gcov_enable_events(void)
372521f2c2SPeter Oberparleiter {
388cbce376SFrantisek Hrbata struct gcov_info *info = NULL;
392521f2c2SPeter Oberparleiter
402521f2c2SPeter Oberparleiter mutex_lock(&gcov_lock);
412521f2c2SPeter Oberparleiter gcov_events_enabled = 1;
428cbce376SFrantisek Hrbata
432521f2c2SPeter Oberparleiter /* Perform event callback for previously registered entries. */
449d796e66SAndrey Ryabinin while ((info = gcov_info_next(info))) {
452521f2c2SPeter Oberparleiter gcov_event(GCOV_ADD, info);
469d796e66SAndrey Ryabinin cond_resched();
479d796e66SAndrey Ryabinin }
488cbce376SFrantisek Hrbata
492521f2c2SPeter Oberparleiter mutex_unlock(&gcov_lock);
502521f2c2SPeter Oberparleiter }
512521f2c2SPeter Oberparleiter
52*7a1d55b9SJohannes Berg /**
53*7a1d55b9SJohannes Berg * store_gcov_u32 - store 32 bit number in gcov format to buffer
54*7a1d55b9SJohannes Berg * @buffer: target buffer or NULL
55*7a1d55b9SJohannes Berg * @off: offset into the buffer
56*7a1d55b9SJohannes Berg * @v: value to be stored
57*7a1d55b9SJohannes Berg *
58*7a1d55b9SJohannes Berg * Number format defined by gcc: numbers are recorded in the 32 bit
59*7a1d55b9SJohannes Berg * unsigned binary form of the endianness of the machine generating the
60*7a1d55b9SJohannes Berg * file. Returns the number of bytes stored. If @buffer is %NULL, doesn't
61*7a1d55b9SJohannes Berg * store anything.
62*7a1d55b9SJohannes Berg */
store_gcov_u32(void * buffer,size_t off,u32 v)63*7a1d55b9SJohannes Berg size_t store_gcov_u32(void *buffer, size_t off, u32 v)
64*7a1d55b9SJohannes Berg {
65*7a1d55b9SJohannes Berg u32 *data;
66*7a1d55b9SJohannes Berg
67*7a1d55b9SJohannes Berg if (buffer) {
68*7a1d55b9SJohannes Berg data = buffer + off;
69*7a1d55b9SJohannes Berg *data = v;
70*7a1d55b9SJohannes Berg }
71*7a1d55b9SJohannes Berg
72*7a1d55b9SJohannes Berg return sizeof(*data);
73*7a1d55b9SJohannes Berg }
74*7a1d55b9SJohannes Berg
75*7a1d55b9SJohannes Berg /**
76*7a1d55b9SJohannes Berg * store_gcov_u64 - store 64 bit number in gcov format to buffer
77*7a1d55b9SJohannes Berg * @buffer: target buffer or NULL
78*7a1d55b9SJohannes Berg * @off: offset into the buffer
79*7a1d55b9SJohannes Berg * @v: value to be stored
80*7a1d55b9SJohannes Berg *
81*7a1d55b9SJohannes Berg * Number format defined by gcc: numbers are recorded in the 32 bit
82*7a1d55b9SJohannes Berg * unsigned binary form of the endianness of the machine generating the
83*7a1d55b9SJohannes Berg * file. 64 bit numbers are stored as two 32 bit numbers, the low part
84*7a1d55b9SJohannes Berg * first. Returns the number of bytes stored. If @buffer is %NULL, doesn't store
85*7a1d55b9SJohannes Berg * anything.
86*7a1d55b9SJohannes Berg */
store_gcov_u64(void * buffer,size_t off,u64 v)87*7a1d55b9SJohannes Berg size_t store_gcov_u64(void *buffer, size_t off, u64 v)
88*7a1d55b9SJohannes Berg {
89*7a1d55b9SJohannes Berg u32 *data;
90*7a1d55b9SJohannes Berg
91*7a1d55b9SJohannes Berg if (buffer) {
92*7a1d55b9SJohannes Berg data = buffer + off;
93*7a1d55b9SJohannes Berg
94*7a1d55b9SJohannes Berg data[0] = (v & 0xffffffffUL);
95*7a1d55b9SJohannes Berg data[1] = (v >> 32);
96*7a1d55b9SJohannes Berg }
97*7a1d55b9SJohannes Berg
98*7a1d55b9SJohannes Berg return sizeof(*data) * 2;
99*7a1d55b9SJohannes Berg }
100*7a1d55b9SJohannes Berg
1012521f2c2SPeter Oberparleiter #ifdef CONFIG_MODULES
1022521f2c2SPeter Oberparleiter /* Update list and generate events when modules are unloaded. */
gcov_module_notifier(struct notifier_block * nb,unsigned long event,void * data)1032521f2c2SPeter Oberparleiter static int gcov_module_notifier(struct notifier_block *nb, unsigned long event,
1042521f2c2SPeter Oberparleiter void *data)
1052521f2c2SPeter Oberparleiter {
1062521f2c2SPeter Oberparleiter struct module *mod = data;
1078cbce376SFrantisek Hrbata struct gcov_info *info = NULL;
1088cbce376SFrantisek Hrbata struct gcov_info *prev = NULL;
1092521f2c2SPeter Oberparleiter
1102521f2c2SPeter Oberparleiter if (event != MODULE_STATE_GOING)
1112521f2c2SPeter Oberparleiter return NOTIFY_OK;
1122521f2c2SPeter Oberparleiter mutex_lock(&gcov_lock);
1138cbce376SFrantisek Hrbata
1142521f2c2SPeter Oberparleiter /* Remove entries located in module from linked list. */
1158cbce376SFrantisek Hrbata while ((info = gcov_info_next(info))) {
116e178a5beSGreg Hackmann if (gcov_info_within_module(info, mod)) {
1178cbce376SFrantisek Hrbata gcov_info_unlink(prev, info);
1182521f2c2SPeter Oberparleiter if (gcov_events_enabled)
1192521f2c2SPeter Oberparleiter gcov_event(GCOV_REMOVE, info);
1202521f2c2SPeter Oberparleiter } else
1212521f2c2SPeter Oberparleiter prev = info;
1222521f2c2SPeter Oberparleiter }
1238cbce376SFrantisek Hrbata
1242521f2c2SPeter Oberparleiter mutex_unlock(&gcov_lock);
1252521f2c2SPeter Oberparleiter
1262521f2c2SPeter Oberparleiter return NOTIFY_OK;
1272521f2c2SPeter Oberparleiter }
1282521f2c2SPeter Oberparleiter
1292521f2c2SPeter Oberparleiter static struct notifier_block gcov_nb = {
1302521f2c2SPeter Oberparleiter .notifier_call = gcov_module_notifier,
1312521f2c2SPeter Oberparleiter };
1322521f2c2SPeter Oberparleiter
gcov_init(void)1332521f2c2SPeter Oberparleiter static int __init gcov_init(void)
1342521f2c2SPeter Oberparleiter {
1352521f2c2SPeter Oberparleiter return register_module_notifier(&gcov_nb);
1362521f2c2SPeter Oberparleiter }
1372521f2c2SPeter Oberparleiter device_initcall(gcov_init);
1382521f2c2SPeter Oberparleiter #endif /* CONFIG_MODULES */
139