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Merge branches 'tracing/branch-tracer', 'tracing/ftrace', 'tracing/function-return-tracer', 'tracing/tracepoints' and 'tracing/urgent' into tracing/core

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This commit is contained in:
Ingo Molnar
2008-11-17 09:36:22 +01:00
parent 072b40a156 e7d3737ea1 227a837567 5821e1b74f
commit 3f8e402f34
39 changed files with 889 additions and 477 deletions
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404
kernel/trace/ftrace.c
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@@ -50,6 +50,9 @@ static int last_ftrace_enabled;
/* Quick disabling of function tracer. */
int function_trace_stop;
/* By default, current tracing type is normal tracing. */
enum ftrace_tracing_type_t ftrace_tracing_type = FTRACE_TYPE_ENTER;
/*
* ftrace_disabled is set when an anomaly is discovered.
* ftrace_disabled is much stronger than ftrace_enabled.
@@ -334,7 +337,7 @@ ftrace_record_ip(unsigned long ip)
{
struct dyn_ftrace *rec;
if (!ftrace_enabled || ftrace_disabled)
if (ftrace_disabled)
return NULL;
rec = ftrace_alloc_dyn_node(ip);
@@ -348,129 +351,6 @@ ftrace_record_ip(unsigned long ip)
return rec;
}
#define FTRACE_ADDR ((long)(ftrace_caller))
static int
__ftrace_replace_code(struct dyn_ftrace *rec,
unsigned char *old, unsigned char *new, int enable)
{
unsigned long ip, fl;
ip = rec->ip;
if (ftrace_filtered && enable) {
/*
* If filtering is on:
*
* If this record is set to be filtered and
* is enabled then do nothing.
*
* If this record is set to be filtered and
* it is not enabled, enable it.
*
* If this record is not set to be filtered
* and it is not enabled do nothing.
*
* If this record is set not to trace then
* do nothing.
*
* If this record is set not to trace and
* it is enabled then disable it.
*
* If this record is not set to be filtered and
* it is enabled, disable it.
*/
fl = rec->flags & (FTRACE_FL_FILTER | FTRACE_FL_NOTRACE |
FTRACE_FL_ENABLED);
if ((fl == (FTRACE_FL_FILTER | FTRACE_FL_ENABLED)) ||
(fl == (FTRACE_FL_FILTER | FTRACE_FL_NOTRACE)) ||
!fl || (fl == FTRACE_FL_NOTRACE))
return 0;
/*
* If it is enabled disable it,
* otherwise enable it!
*/
if (fl & FTRACE_FL_ENABLED) {
/* swap new and old */
new = old;
old = ftrace_call_replace(ip, FTRACE_ADDR);
rec->flags &= ~FTRACE_FL_ENABLED;
} else {
new = ftrace_call_replace(ip, FTRACE_ADDR);
rec->flags |= FTRACE_FL_ENABLED;
}
} else {
if (enable) {
/*
* If this record is set not to trace and is
* not enabled, do nothing.
*/
fl = rec->flags & (FTRACE_FL_NOTRACE | FTRACE_FL_ENABLED);
if (fl == FTRACE_FL_NOTRACE)
return 0;
new = ftrace_call_replace(ip, FTRACE_ADDR);
} else
old = ftrace_call_replace(ip, FTRACE_ADDR);
if (enable) {
if (rec->flags & FTRACE_FL_ENABLED)
return 0;
rec->flags |= FTRACE_FL_ENABLED;
} else {
if (!(rec->flags & FTRACE_FL_ENABLED))
return 0;
rec->flags &= ~FTRACE_FL_ENABLED;
}
}
return ftrace_modify_code(ip, old, new);
}
static void ftrace_replace_code(int enable)
{
int i, failed;
unsigned char *new = NULL, *old = NULL;
struct dyn_ftrace *rec;
struct ftrace_page *pg;
if (enable)
old = ftrace_nop_replace();
else
new = ftrace_nop_replace();
for (pg = ftrace_pages_start; pg; pg = pg->next) {
for (i = 0; i < pg->index; i++) {
rec = &pg->records[i];
/* don't modify code that has already faulted */
if (rec->flags & FTRACE_FL_FAILED)
continue;
/* ignore updates to this record's mcount site */
if (get_kprobe((void *)rec->ip)) {
freeze_record(rec);
continue;
} else {
unfreeze_record(rec);
}
failed = __ftrace_replace_code(rec, old, new, enable);
if (failed && (rec->flags & FTRACE_FL_CONVERTED)) {
rec->flags |= FTRACE_FL_FAILED;
if ((system_state == SYSTEM_BOOTING) ||
!core_kernel_text(rec->ip)) {
ftrace_free_rec(rec);
}
}
}
}
}
static void print_ip_ins(const char *fmt, unsigned char *p)
{
int i;
@@ -481,46 +361,162 @@ static void print_ip_ins(const char *fmt, unsigned char *p)
printk(KERN_CONT "%s%02x", i ? ":" : "", p[i]);
}
static void ftrace_bug(int failed, unsigned long ip)
{
switch (failed) {
case -EFAULT:
FTRACE_WARN_ON_ONCE(1);
pr_info("ftrace faulted on modifying ");
print_ip_sym(ip);
break;
case -EINVAL:
FTRACE_WARN_ON_ONCE(1);
pr_info("ftrace failed to modify ");
print_ip_sym(ip);
print_ip_ins(" actual: ", (unsigned char *)ip);
printk(KERN_CONT "\n");
break;
case -EPERM:
FTRACE_WARN_ON_ONCE(1);
pr_info("ftrace faulted on writing ");
print_ip_sym(ip);
break;
default:
FTRACE_WARN_ON_ONCE(1);
pr_info("ftrace faulted on unknown error ");
print_ip_sym(ip);
}
}
static int
ftrace_code_disable(struct dyn_ftrace *rec)
__ftrace_replace_code(struct dyn_ftrace *rec, int enable)
{
unsigned long ip, fl;
unsigned long ftrace_addr;
#ifdef CONFIG_FUNCTION_RET_TRACER
if (ftrace_tracing_type == FTRACE_TYPE_ENTER)
ftrace_addr = (unsigned long)ftrace_caller;
else
ftrace_addr = (unsigned long)ftrace_return_caller;
#else
ftrace_addr = (unsigned long)ftrace_caller;
#endif
ip = rec->ip;
/*
* If this record is not to be traced and
* it is not enabled then do nothing.
*
* If this record is not to be traced and
* it is enabled then disabled it.
*
*/
if (rec->flags & FTRACE_FL_NOTRACE) {
if (rec->flags & FTRACE_FL_ENABLED)
rec->flags &= ~FTRACE_FL_ENABLED;
else
return 0;
} else if (ftrace_filtered && enable) {
/*
* Filtering is on:
*/
fl = rec->flags & (FTRACE_FL_FILTER | FTRACE_FL_ENABLED);
/* Record is filtered and enabled, do nothing */
if (fl == (FTRACE_FL_FILTER | FTRACE_FL_ENABLED))
return 0;
/* Record is not filtered and is not enabled do nothing */
if (!fl)
return 0;
/* Record is not filtered but enabled, disable it */
if (fl == FTRACE_FL_ENABLED)
rec->flags &= ~FTRACE_FL_ENABLED;
else
/* Otherwise record is filtered but not enabled, enable it */
rec->flags |= FTRACE_FL_ENABLED;
} else {
/* Disable or not filtered */
if (enable) {
/* if record is enabled, do nothing */
if (rec->flags & FTRACE_FL_ENABLED)
return 0;
rec->flags |= FTRACE_FL_ENABLED;
} else {
/* if record is not enabled do nothing */
if (!(rec->flags & FTRACE_FL_ENABLED))
return 0;
rec->flags &= ~FTRACE_FL_ENABLED;
}
}
if (rec->flags & FTRACE_FL_ENABLED)
return ftrace_make_call(rec, ftrace_addr);
else
return ftrace_make_nop(NULL, rec, ftrace_addr);
}
static void ftrace_replace_code(int enable)
{
int i, failed;
struct dyn_ftrace *rec;
struct ftrace_page *pg;
for (pg = ftrace_pages_start; pg; pg = pg->next) {
for (i = 0; i < pg->index; i++) {
rec = &pg->records[i];
/*
* Skip over free records and records that have
* failed.
*/
if (rec->flags & FTRACE_FL_FREE ||
rec->flags & FTRACE_FL_FAILED)
continue;
/* ignore updates to this record's mcount site */
if (get_kprobe((void *)rec->ip)) {
freeze_record(rec);
continue;
} else {
unfreeze_record(rec);
}
failed = __ftrace_replace_code(rec, enable);
if (failed && (rec->flags & FTRACE_FL_CONVERTED)) {
rec->flags |= FTRACE_FL_FAILED;
if ((system_state == SYSTEM_BOOTING) ||
!core_kernel_text(rec->ip)) {
ftrace_free_rec(rec);
} else
ftrace_bug(failed, rec->ip);
}
}
}
}
static int
ftrace_code_disable(struct module *mod, struct dyn_ftrace *rec)
{
unsigned long ip;
unsigned char *nop, *call;
int ret;
ip = rec->ip;
nop = ftrace_nop_replace();
call = ftrace_call_replace(ip, mcount_addr);
ret = ftrace_modify_code(ip, call, nop);
ret = ftrace_make_nop(mod, rec, mcount_addr);
if (ret) {
switch (ret) {
case -EFAULT:
FTRACE_WARN_ON_ONCE(1);
pr_info("ftrace faulted on modifying ");
print_ip_sym(ip);
break;
case -EINVAL:
FTRACE_WARN_ON_ONCE(1);
pr_info("ftrace failed to modify ");
print_ip_sym(ip);
print_ip_ins(" expected: ", call);
print_ip_ins(" actual: ", (unsigned char *)ip);
print_ip_ins(" replace: ", nop);
printk(KERN_CONT "\n");
break;
case -EPERM:
FTRACE_WARN_ON_ONCE(1);
pr_info("ftrace faulted on writing ");
print_ip_sym(ip);
break;
default:
FTRACE_WARN_ON_ONCE(1);
pr_info("ftrace faulted on unknown error ");
print_ip_sym(ip);
}
ftrace_bug(ret, ip);
rec->flags |= FTRACE_FL_FAILED;
return 0;
}
@@ -560,8 +556,7 @@ static void ftrace_startup(void)
mutex_lock(&ftrace_start_lock);
ftrace_start_up++;
if (ftrace_start_up == 1)
command |= FTRACE_ENABLE_CALLS;
command |= FTRACE_ENABLE_CALLS;
if (saved_ftrace_func != ftrace_trace_function) {
saved_ftrace_func = ftrace_trace_function;
@@ -639,7 +634,7 @@ static cycle_t ftrace_update_time;
static unsigned long ftrace_update_cnt;
unsigned long ftrace_update_tot_cnt;
static int ftrace_update_code(void)
static int ftrace_update_code(struct module *mod)
{
struct dyn_ftrace *p, *t;
cycle_t start, stop;
@@ -656,7 +651,7 @@ static int ftrace_update_code(void)
list_del_init(&p->list);
/* convert record (i.e, patch mcount-call with NOP) */
if (ftrace_code_disable(p)) {
if (ftrace_code_disable(mod, p)) {
p->flags |= FTRACE_FL_CONVERTED;
ftrace_update_cnt++;
} else
@@ -699,7 +694,7 @@ static int __init ftrace_dyn_table_alloc(unsigned long num_to_init)
cnt = num_to_init / ENTRIES_PER_PAGE;
pr_info("ftrace: allocating %ld entries in %d pages\n",
num_to_init, cnt);
num_to_init, cnt + 1);
for (i = 0; i < cnt; i++) {
pg->next = (void *)get_zeroed_page(GFP_KERNEL);
@@ -782,13 +777,11 @@ static void *t_start(struct seq_file *m, loff_t *pos)
void *p = NULL;
loff_t l = -1;
if (*pos != iter->pos) {
for (p = t_next(m, p, &l); p && l < *pos; p = t_next(m, p, &l))
;
} else {
l = *pos;
p = t_next(m, p, &l);
}
if (*pos > iter->pos)
*pos = iter->pos;
l = *pos;
p = t_next(m, p, &l);
return p;
}
@@ -799,15 +792,21 @@ static void t_stop(struct seq_file *m, void *p)
static int t_show(struct seq_file *m, void *v)
{
struct ftrace_iterator *iter = m->private;
struct dyn_ftrace *rec = v;
char str[KSYM_SYMBOL_LEN];
int ret = 0;
if (!rec)
return 0;
kallsyms_lookup(rec->ip, NULL, NULL, NULL, str);
seq_printf(m, "%s\n", str);
ret = seq_printf(m, "%s\n", str);
if (ret < 0) {
iter->pos--;
iter->idx--;
}
return 0;
}
@@ -833,7 +832,7 @@ ftrace_avail_open(struct inode *inode, struct file *file)
return -ENOMEM;
iter->pg = ftrace_pages_start;
iter->pos = -1;
iter->pos = 0;
ret = seq_open(file, &show_ftrace_seq_ops);
if (!ret) {
@@ -920,7 +919,7 @@ ftrace_regex_open(struct inode *inode, struct file *file, int enable)
if (file->f_mode & FMODE_READ) {
iter->pg = ftrace_pages_start;
iter->pos = -1;
iter->pos = 0;
iter->flags = enable ? FTRACE_ITER_FILTER :
FTRACE_ITER_NOTRACE;
@@ -1211,7 +1210,7 @@ ftrace_regex_release(struct inode *inode, struct file *file, int enable)
mutex_lock(&ftrace_sysctl_lock);
mutex_lock(&ftrace_start_lock);
if (iter->filtered && ftrace_start_up && ftrace_enabled)
if (ftrace_start_up && ftrace_enabled)
ftrace_run_update_code(FTRACE_ENABLE_CALLS);
mutex_unlock(&ftrace_start_lock);
mutex_unlock(&ftrace_sysctl_lock);
@@ -1298,7 +1297,8 @@ static __init int ftrace_init_debugfs(void)
fs_initcall(ftrace_init_debugfs);
static int ftrace_convert_nops(unsigned long *start,
static int ftrace_convert_nops(struct module *mod,
unsigned long *start,
unsigned long *end)
{
unsigned long *p;
@@ -1309,23 +1309,32 @@ static int ftrace_convert_nops(unsigned long *start,
p = start;
while (p < end) {
addr = ftrace_call_adjust(*p++);
/*
* Some architecture linkers will pad between
* the different mcount_loc sections of different
* object files to satisfy alignments.
* Skip any NULL pointers.
*/
if (!addr)
continue;
ftrace_record_ip(addr);
}
/* disable interrupts to prevent kstop machine */
local_irq_save(flags);
ftrace_update_code();
ftrace_update_code(mod);
local_irq_restore(flags);
mutex_unlock(&ftrace_start_lock);
return 0;
}
void ftrace_init_module(unsigned long *start, unsigned long *end)
void ftrace_init_module(struct module *mod,
unsigned long *start, unsigned long *end)
{
if (ftrace_disabled || start == end)
return;
ftrace_convert_nops(start, end);
ftrace_convert_nops(mod, start, end);
}
extern unsigned long __start_mcount_loc[];
@@ -1355,7 +1364,8 @@ void __init ftrace_init(void)
last_ftrace_enabled = ftrace_enabled = 1;
ret = ftrace_convert_nops(__start_mcount_loc,
ret = ftrace_convert_nops(NULL,
__start_mcount_loc,
__stop_mcount_loc);
return;
@@ -1411,10 +1421,17 @@ int register_ftrace_function(struct ftrace_ops *ops)
return -1;
mutex_lock(&ftrace_sysctl_lock);
if (ftrace_tracing_type == FTRACE_TYPE_RETURN) {
ret = -EBUSY;
goto out;
}
ret = __register_ftrace_function(ops);
ftrace_startup();
mutex_unlock(&ftrace_sysctl_lock);
out:
mutex_unlock(&ftrace_sysctl_lock);
return ret;
}
@@ -1480,16 +1497,45 @@ ftrace_enable_sysctl(struct ctl_table *table, int write,
}
#ifdef CONFIG_FUNCTION_RET_TRACER
/* The callback that hooks the return of a function */
trace_function_return_t ftrace_function_return =
(trace_function_return_t)ftrace_stub;
void register_ftrace_return(trace_function_return_t func)
int register_ftrace_return(trace_function_return_t func)
{
int ret = 0;
mutex_lock(&ftrace_sysctl_lock);
/*
* Don't launch return tracing if normal function
* tracing is already running.
*/
if (ftrace_trace_function != ftrace_stub) {
ret = -EBUSY;
goto out;
}
ftrace_tracing_type = FTRACE_TYPE_RETURN;
ftrace_function_return = func;
ftrace_startup();
out:
mutex_unlock(&ftrace_sysctl_lock);
return ret;
}
void unregister_ftrace_return(void)
{
mutex_lock(&ftrace_sysctl_lock);
ftrace_function_return = (trace_function_return_t)ftrace_stub;
ftrace_shutdown();
/* Restore normal tracing type */
ftrace_tracing_type = FTRACE_TYPE_ENTER;
mutex_unlock(&ftrace_sysctl_lock);
}
#endif