#include <linux/hardirq.h>
#include <linux/kthread.h>
#include <linux/uaccess.h>
-#include <linux/kprobes.h>
#include <linux/ftrace.h>
#include <linux/sysctl.h>
+#include <linux/slab.h>
#include <linux/ctype.h>
#include <linux/list.h>
#include <linux/hash.h>
+#include <linux/rcupdate.h>
#include <trace/events/sched.h>
/* Quick disabling of function tracer. */
int function_trace_stop;
+/* List for set_ftrace_pid's pids. */
+LIST_HEAD(ftrace_pids);
+struct ftrace_pid {
+ struct list_head list;
+ struct pid *pid;
+};
+
/*
* ftrace_disabled is set when an anomaly is discovered.
* ftrace_disabled is much stronger than ftrace_enabled.
ftrace_func_t __ftrace_trace_function __read_mostly = ftrace_stub;
ftrace_func_t ftrace_pid_function __read_mostly = ftrace_stub;
+/*
+ * Traverse the ftrace_list, invoking all entries. The reason that we
+ * can use rcu_dereference_raw() is that elements removed from this list
+ * are simply leaked, so there is no need to interact with a grace-period
+ * mechanism. The rcu_dereference_raw() calls are needed to handle
+ * concurrent insertions into the ftrace_list.
+ *
+ * Silly Alpha and silly pointer-speculation compiler optimizations!
+ */
static void ftrace_list_func(unsigned long ip, unsigned long parent_ip)
{
- struct ftrace_ops *op = ftrace_list;
-
- /* in case someone actually ports this to alpha! */
- read_barrier_depends();
+ struct ftrace_ops *op = rcu_dereference_raw(ftrace_list); /*see above*/
while (op != &ftrace_list_end) {
- /* silly alpha */
- read_barrier_depends();
op->func(ip, parent_ip);
- op = op->next;
+ op = rcu_dereference_raw(op->next); /*see above*/
};
}
* the ops->next pointer is valid before another CPU sees
* the ops pointer included into the ftrace_list.
*/
- smp_wmb();
- ftrace_list = ops;
+ rcu_assign_pointer(ftrace_list, ops);
if (ftrace_enabled) {
ftrace_func_t func;
else
func = ftrace_list_func;
- if (ftrace_pid_trace) {
+ if (!list_empty(&ftrace_pids)) {
set_ftrace_pid_function(func);
func = ftrace_pid_func;
}
if (ftrace_list->next == &ftrace_list_end) {
ftrace_func_t func = ftrace_list->func;
- if (ftrace_pid_trace) {
+ if (!list_empty(&ftrace_pids)) {
set_ftrace_pid_function(func);
func = ftrace_pid_func;
}
if (ftrace_trace_function == ftrace_stub)
return;
+#ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST
func = ftrace_trace_function;
+#else
+ func = __ftrace_trace_function;
+#endif
- if (ftrace_pid_trace) {
+ if (!list_empty(&ftrace_pids)) {
set_ftrace_pid_function(func);
func = ftrace_pid_func;
} else {
unsigned long counter;
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
unsigned long long time;
+ unsigned long long time_squared;
#endif
};
{
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
seq_printf(m, " Function "
- "Hit Time Avg\n"
+ "Hit Time Avg s^2\n"
" -------- "
- "--- ---- ---\n");
+ "--- ---- --- ---\n");
#else
seq_printf(m, " Function Hit\n"
" -------- ---\n");
static DEFINE_MUTEX(mutex);
static struct trace_seq s;
unsigned long long avg;
+ unsigned long long stddev;
#endif
kallsyms_lookup(rec->ip, NULL, NULL, NULL, str);
avg = rec->time;
do_div(avg, rec->counter);
+ /* Sample standard deviation (s^2) */
+ if (rec->counter <= 1)
+ stddev = 0;
+ else {
+ stddev = rec->time_squared - rec->counter * avg * avg;
+ /*
+ * Divide only 1000 for ns^2 -> us^2 conversion.
+ * trace_print_graph_duration will divide 1000 again.
+ */
+ do_div(stddev, (rec->counter - 1) * 1000);
+ }
+
mutex_lock(&mutex);
trace_seq_init(&s);
trace_print_graph_duration(rec->time, &s);
trace_seq_puts(&s, " ");
trace_print_graph_duration(avg, &s);
+ trace_seq_puts(&s, " ");
+ trace_print_graph_duration(stddev, &s);
trace_print_seq(m, &s);
mutex_unlock(&mutex);
#endif
if (!stat->hash || !ftrace_profile_enabled)
goto out;
+ /* If the calltime was zero'd ignore it */
+ if (!trace->calltime)
+ goto out;
+
calltime = trace->rettime - trace->calltime;
if (!(trace_flags & TRACE_ITER_GRAPH_TIME)) {
}
rec = ftrace_find_profiled_func(stat, trace->func);
- if (rec)
+ if (rec) {
rec->time += calltime;
+ rec->time_squared += calltime * calltime;
+ }
out:
local_irq_restore(flags);
out:
mutex_unlock(&ftrace_profile_lock);
- filp->f_pos += cnt;
+ *ppos += cnt;
return cnt;
}
}
#endif /* CONFIG_FUNCTION_PROFILER */
-/* set when tracing only a pid */
-struct pid *ftrace_pid_trace;
static struct pid * const ftrace_swapper_pid = &init_struct_pid;
#ifdef CONFIG_DYNAMIC_FTRACE
} \
}
-#ifdef CONFIG_KPROBES
-
-static int frozen_record_count;
-
-static inline void freeze_record(struct dyn_ftrace *rec)
-{
- if (!(rec->flags & FTRACE_FL_FROZEN)) {
- rec->flags |= FTRACE_FL_FROZEN;
- frozen_record_count++;
- }
-}
-
-static inline void unfreeze_record(struct dyn_ftrace *rec)
-{
- if (rec->flags & FTRACE_FL_FROZEN) {
- rec->flags &= ~FTRACE_FL_FROZEN;
- frozen_record_count--;
- }
-}
-
-static inline int record_frozen(struct dyn_ftrace *rec)
-{
- return rec->flags & FTRACE_FL_FROZEN;
-}
-#else
-# define freeze_record(rec) ({ 0; })
-# define unfreeze_record(rec) ({ 0; })
-# define record_frozen(rec) ({ 0; })
-#endif /* CONFIG_KPROBES */
-
static void ftrace_free_rec(struct dyn_ftrace *rec)
{
rec->freelist = ftrace_free_records;
}
+/* Return 1 if the address range is reserved for ftrace */
+int ftrace_text_reserved(void *start, void *end)
+{
+ struct dyn_ftrace *rec;
+ struct ftrace_page *pg;
+
+ do_for_each_ftrace_rec(pg, rec) {
+ if (rec->ip <= (unsigned long)end &&
+ rec->ip + MCOUNT_INSN_SIZE > (unsigned long)start)
+ return 1;
+ } while_for_each_ftrace_rec();
+ return 0;
+}
+
+
static int
__ftrace_replace_code(struct dyn_ftrace *rec, int enable)
{
!(rec->flags & FTRACE_FL_CONVERTED))
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_FAILED;
- if ((system_state == SYSTEM_BOOTING) ||
- !core_kernel_text(rec->ip)) {
- ftrace_free_rec(rec);
- } else {
- ftrace_bug(failed, rec->ip);
- /* Stop processing */
- return;
- }
+ ftrace_bug(failed, rec->ip);
+ /* Stop processing */
+ return;
}
} while_for_each_ftrace_rec();
}
ftrace_new_addrs = p->newlist;
p->flags = 0L;
- /* convert record (i.e, patch mcount-call with NOP) */
- if (ftrace_code_disable(mod, p)) {
- p->flags |= FTRACE_FL_CONVERTED;
- ftrace_update_cnt++;
- } else
+ /*
+ * Do the initial record convertion from mcount jump
+ * to the NOP instructions.
+ */
+ if (!ftrace_code_disable(mod, p)) {
ftrace_free_rec(p);
+ continue;
+ }
+
+ p->flags |= FTRACE_FL_CONVERTED;
+ ftrace_update_cnt++;
+
+ /*
+ * If the tracing is enabled, go ahead and enable the record.
+ *
+ * The reason not to enable the record immediatelly is the
+ * inherent check of ftrace_make_nop/ftrace_make_call for
+ * correct previous instructions. Making first the NOP
+ * conversion puts the module to the correct state, thus
+ * passing the ftrace_make_call check.
+ */
+ if (ftrace_start_up) {
+ int failed = __ftrace_replace_code(p, 1);
+ if (failed) {
+ ftrace_bug(failed, p->ip);
+ ftrace_free_rec(p);
+ }
+ }
}
stop = ftrace_now(raw_smp_processor_id());
return 0;
}
-static struct seq_operations show_ftrace_seq_ops = {
+static const struct seq_operations show_ftrace_seq_ops = {
.start = t_start,
.next = t_next,
.stop = t_stop,
if (!ret) {
struct seq_file *m = file->private_data;
m->private = iter;
- } else
+ } else {
+ trace_parser_put(&iter->parser);
kfree(iter);
+ }
} else
file->private_data = iter;
mutex_unlock(&ftrace_regex_lock);
return ret;
}
-enum {
- MATCH_FULL,
- MATCH_FRONT_ONLY,
- MATCH_MIDDLE_ONLY,
- MATCH_END_ONLY,
-};
-
-/*
- * (static function - no need for kernel doc)
- *
- * Pass in a buffer containing a glob and this function will
- * set search to point to the search part of the buffer and
- * return the type of search it is (see enum above).
- * This does modify buff.
- *
- * Returns enum type.
- * search returns the pointer to use for comparison.
- * not returns 1 if buff started with a '!'
- * 0 otherwise.
- */
-static int
-ftrace_setup_glob(char *buff, int len, char **search, int *not)
-{
- int type = MATCH_FULL;
- int i;
-
- if (buff[0] == '!') {
- *not = 1;
- buff++;
- len--;
- } else
- *not = 0;
-
- *search = buff;
-
- for (i = 0; i < len; i++) {
- if (buff[i] == '*') {
- if (!i) {
- *search = buff + 1;
- type = MATCH_END_ONLY;
- } else {
- if (type == MATCH_END_ONLY)
- type = MATCH_MIDDLE_ONLY;
- else
- type = MATCH_FRONT_ONLY;
- buff[i] = 0;
- break;
- }
- }
- }
-
- return type;
-}
-
static int ftrace_match(char *str, char *regex, int len, int type)
{
int matched = 0;
- char *ptr;
+ int slen;
switch (type) {
case MATCH_FULL:
matched = 1;
break;
case MATCH_END_ONLY:
- ptr = strstr(str, regex);
- if (ptr && (ptr[len] == 0))
+ slen = strlen(str);
+ if (slen >= len && memcmp(str + slen - len, regex, len) == 0)
matched = 1;
break;
}
return ftrace_match(str, regex, len, type);
}
-static void ftrace_match_records(char *buff, int len, int enable)
+static int ftrace_match_records(char *buff, int len, int enable)
{
unsigned int search_len;
struct ftrace_page *pg;
char *search;
int type;
int not;
+ int found = 0;
flag = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE;
- type = ftrace_setup_glob(buff, len, &search, ¬);
+ type = filter_parse_regex(buff, len, &search, ¬);
search_len = strlen(search);
rec->flags &= ~flag;
else
rec->flags |= flag;
+ found = 1;
}
/*
* Only enable filtering if we have a function that
ftrace_filtered = 1;
} while_for_each_ftrace_rec();
mutex_unlock(&ftrace_lock);
+
+ return found;
}
static int
return 1;
}
-static void ftrace_match_module_records(char *buff, char *mod, int enable)
+static int ftrace_match_module_records(char *buff, char *mod, int enable)
{
unsigned search_len = 0;
struct ftrace_page *pg;
char *search = buff;
unsigned long flag;
int not = 0;
+ int found = 0;
flag = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE;
}
if (strlen(buff)) {
- type = ftrace_setup_glob(buff, strlen(buff), &search, ¬);
+ type = filter_parse_regex(buff, strlen(buff), &search, ¬);
search_len = strlen(search);
}
rec->flags &= ~flag;
else
rec->flags |= flag;
+ found = 1;
}
if (enable && (rec->flags & FTRACE_FL_FILTER))
ftrace_filtered = 1;
} while_for_each_ftrace_rec();
mutex_unlock(&ftrace_lock);
+
+ return found;
}
/*
if (!strlen(mod))
return -EINVAL;
- ftrace_match_module_records(func, mod, enable);
- return 0;
+ if (ftrace_match_module_records(func, mod, enable))
+ return 0;
+ return -EINVAL;
}
static struct ftrace_func_command ftrace_mod_cmd = {
int count = 0;
char *search;
- type = ftrace_setup_glob(glob, strlen(glob), &search, ¬);
+ type = filter_parse_regex(glob, strlen(glob), &search, ¬);
len = strlen(search);
/* we do not support '!' for function probes */
else if (glob) {
int not;
- type = ftrace_setup_glob(glob, strlen(glob), &search, ¬);
+ type = filter_parse_regex(glob, strlen(glob), &search, ¬);
len = strlen(search);
/* we do not support '!' for function probes */
func = strsep(&next, ":");
if (!next) {
- ftrace_match_records(func, len, enable);
- return 0;
+ if (ftrace_match_records(func, len, enable))
+ return 0;
+ return ret;
}
/* command found */
struct trace_parser *parser;
ssize_t ret, read;
- if (!cnt || cnt < 0)
+ if (!cnt)
return 0;
mutex_lock(&ftrace_regex_lock);
parser = &iter->parser;
read = trace_get_user(parser, ubuf, cnt, ppos);
- if (trace_parser_loaded(parser) &&
+ if (read >= 0 && trace_parser_loaded(parser) &&
!trace_parser_cont(parser)) {
ret = ftrace_process_regex(parser->buffer,
parser->idx, enable);
- if (ret)
- goto out;
-
trace_parser_clear(parser);
+ if (ret)
+ goto out_unlock;
}
ret = read;
-
+out_unlock:
mutex_unlock(&ftrace_regex_lock);
-out:
+
return ret;
}
}
__setup("ftrace_filter=", set_ftrace_filter);
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+static char ftrace_graph_buf[FTRACE_FILTER_SIZE] __initdata;
+static int ftrace_set_func(unsigned long *array, int *idx, char *buffer);
+
+static int __init set_graph_function(char *str)
+{
+ strlcpy(ftrace_graph_buf, str, FTRACE_FILTER_SIZE);
+ return 1;
+}
+__setup("ftrace_graph_filter=", set_graph_function);
+
+static void __init set_ftrace_early_graph(char *buf)
+{
+ int ret;
+ char *func;
+
+ while (buf) {
+ func = strsep(&buf, ",");
+ /* we allow only one expression at a time */
+ ret = ftrace_set_func(ftrace_graph_funcs, &ftrace_graph_count,
+ func);
+ if (ret)
+ printk(KERN_DEBUG "ftrace: function %s not "
+ "traceable\n", func);
+ }
+}
+#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
+
static void __init set_ftrace_early_filter(char *buf, int enable)
{
char *func;
set_ftrace_early_filter(ftrace_filter_buf, 1);
if (ftrace_notrace_buf[0])
set_ftrace_early_filter(ftrace_notrace_buf, 0);
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+ if (ftrace_graph_buf[0])
+ set_ftrace_early_graph(ftrace_graph_buf);
+#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
}
static int
static DEFINE_MUTEX(graph_lock);
int ftrace_graph_count;
+int ftrace_graph_filter_enabled;
unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS] __read_mostly;
static void *
__g_next(struct seq_file *m, loff_t *pos)
{
- unsigned long *array = m->private;
-
if (*pos >= ftrace_graph_count)
return NULL;
- return &array[*pos];
+ return &ftrace_graph_funcs[*pos];
}
static void *
mutex_lock(&graph_lock);
/* Nothing, tell g_show to print all functions are enabled */
- if (!ftrace_graph_count && !*pos)
+ if (!ftrace_graph_filter_enabled && !*pos)
return (void *)1;
return __g_next(m, pos);
return 0;
}
-static struct seq_operations ftrace_graph_seq_ops = {
+static const struct seq_operations ftrace_graph_seq_ops = {
.start = g_start,
.next = g_next,
.stop = g_stop,
mutex_lock(&graph_lock);
if ((file->f_mode & FMODE_WRITE) &&
(file->f_flags & O_TRUNC)) {
+ ftrace_graph_filter_enabled = 0;
ftrace_graph_count = 0;
memset(ftrace_graph_funcs, 0, sizeof(ftrace_graph_funcs));
}
+ mutex_unlock(&graph_lock);
- if (file->f_mode & FMODE_READ) {
+ if (file->f_mode & FMODE_READ)
ret = seq_open(file, &ftrace_graph_seq_ops);
- if (!ret) {
- struct seq_file *m = file->private_data;
- m->private = ftrace_graph_funcs;
- }
- } else
- file->private_data = ftrace_graph_funcs;
- mutex_unlock(&graph_lock);
return ret;
}
struct dyn_ftrace *rec;
struct ftrace_page *pg;
int search_len;
- int found = 0;
+ int fail = 1;
int type, not;
char *search;
bool exists;
return -ENODEV;
/* decode regex */
- type = ftrace_setup_glob(buffer, strlen(buffer), &search, ¬);
- if (not)
- return -EINVAL;
+ type = filter_parse_regex(buffer, strlen(buffer), &search, ¬);
+ if (!not && *idx >= FTRACE_GRAPH_MAX_FUNCS)
+ return -EBUSY;
search_len = strlen(search);
mutex_lock(&ftrace_lock);
do_for_each_ftrace_rec(pg, rec) {
- if (*idx >= FTRACE_GRAPH_MAX_FUNCS)
- break;
-
if (rec->flags & (FTRACE_FL_FAILED | FTRACE_FL_FREE))
continue;
if (ftrace_match_record(rec, search, search_len, type)) {
- /* ensure it is not already in the array */
+ /* if it is in the array */
exists = false;
- for (i = 0; i < *idx; i++)
+ for (i = 0; i < *idx; i++) {
if (array[i] == rec->ip) {
exists = true;
break;
}
- if (!exists) {
- array[(*idx)++] = rec->ip;
- found = 1;
+ }
+
+ if (!not) {
+ fail = 0;
+ if (!exists) {
+ array[(*idx)++] = rec->ip;
+ if (*idx >= FTRACE_GRAPH_MAX_FUNCS)
+ goto out;
+ }
+ } else {
+ if (exists) {
+ array[i] = array[--(*idx)];
+ array[*idx] = 0;
+ fail = 0;
+ }
}
}
} while_for_each_ftrace_rec();
-
+out:
mutex_unlock(&ftrace_lock);
- return found ? 0 : -EINVAL;
+ if (fail)
+ return -EINVAL;
+
+ ftrace_graph_filter_enabled = 1;
+ return 0;
}
static ssize_t
size_t cnt, loff_t *ppos)
{
struct trace_parser parser;
- unsigned long *array;
- size_t read = 0;
- ssize_t ret;
+ ssize_t read, ret;
- if (!cnt || cnt < 0)
+ if (!cnt)
return 0;
mutex_lock(&graph_lock);
- if (ftrace_graph_count >= FTRACE_GRAPH_MAX_FUNCS) {
- ret = -EBUSY;
- goto out;
- }
-
- if (file->f_mode & FMODE_READ) {
- struct seq_file *m = file->private_data;
- array = m->private;
- } else
- array = file->private_data;
-
if (trace_parser_get_init(&parser, FTRACE_BUFF_MAX)) {
ret = -ENOMEM;
- goto out;
+ goto out_unlock;
}
read = trace_get_user(&parser, ubuf, cnt, ppos);
- if (trace_parser_loaded((&parser))) {
+ if (read >= 0 && trace_parser_loaded((&parser))) {
parser.buffer[parser.idx] = 0;
/* we allow only one expression at a time */
- ret = ftrace_set_func(array, &ftrace_graph_count,
+ ret = ftrace_set_func(ftrace_graph_funcs, &ftrace_graph_count,
parser.buffer);
if (ret)
- goto out;
+ goto out_free;
}
ret = read;
- out:
+
+out_free:
trace_parser_put(&parser);
+out_unlock:
mutex_unlock(&graph_lock);
return ret;
return 0;
}
-static int ftrace_convert_nops(struct module *mod,
+static int ftrace_process_locs(struct module *mod,
unsigned long *start,
unsigned long *end)
{
}
#ifdef CONFIG_MODULES
-void ftrace_release(void *start, void *end)
+void ftrace_release_mod(struct module *mod)
{
struct dyn_ftrace *rec;
struct ftrace_page *pg;
- unsigned long s = (unsigned long)start;
- unsigned long e = (unsigned long)end;
- if (ftrace_disabled || !start || start == end)
+ if (ftrace_disabled)
return;
mutex_lock(&ftrace_lock);
do_for_each_ftrace_rec(pg, rec) {
- if ((rec->ip >= s) && (rec->ip < e)) {
+ if (within_module_core(rec->ip, mod)) {
/*
* rec->ip is changed in ftrace_free_rec()
* It should not between s and e if record was freed.
{
if (ftrace_disabled || start == end)
return;
- ftrace_convert_nops(mod, start, end);
+ ftrace_process_locs(mod, start, end);
}
static int ftrace_module_notify(struct notifier_block *self,
mod->num_ftrace_callsites);
break;
case MODULE_STATE_GOING:
- ftrace_release(mod->ftrace_callsites,
- mod->ftrace_callsites +
- mod->num_ftrace_callsites);
+ ftrace_release_mod(mod);
break;
}
last_ftrace_enabled = ftrace_enabled = 1;
- ret = ftrace_convert_nops(NULL,
+ ret = ftrace_process_locs(NULL,
__start_mcount_loc,
__stop_mcount_loc);
# define ftrace_shutdown_sysctl() do { } while (0)
#endif /* CONFIG_DYNAMIC_FTRACE */
-static ssize_t
-ftrace_pid_read(struct file *file, char __user *ubuf,
- size_t cnt, loff_t *ppos)
-{
- char buf[64];
- int r;
-
- if (ftrace_pid_trace == ftrace_swapper_pid)
- r = sprintf(buf, "swapper tasks\n");
- else if (ftrace_pid_trace)
- r = sprintf(buf, "%u\n", pid_vnr(ftrace_pid_trace));
- else
- r = sprintf(buf, "no pid\n");
-
- return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
-}
-
static void clear_ftrace_swapper(void)
{
struct task_struct *p;
rcu_read_unlock();
}
-static void clear_ftrace_pid_task(struct pid **pid)
+static void clear_ftrace_pid_task(struct pid *pid)
{
- if (*pid == ftrace_swapper_pid)
+ if (pid == ftrace_swapper_pid)
clear_ftrace_swapper();
else
- clear_ftrace_pid(*pid);
-
- *pid = NULL;
+ clear_ftrace_pid(pid);
}
static void set_ftrace_pid_task(struct pid *pid)
set_ftrace_pid(pid);
}
-static ssize_t
-ftrace_pid_write(struct file *filp, const char __user *ubuf,
- size_t cnt, loff_t *ppos)
+static int ftrace_pid_add(int p)
{
struct pid *pid;
- char buf[64];
- long val;
- int ret;
+ struct ftrace_pid *fpid;
+ int ret = -EINVAL;
- if (cnt >= sizeof(buf))
- return -EINVAL;
+ mutex_lock(&ftrace_lock);
- if (copy_from_user(&buf, ubuf, cnt))
- return -EFAULT;
+ if (!p)
+ pid = ftrace_swapper_pid;
+ else
+ pid = find_get_pid(p);
- buf[cnt] = 0;
+ if (!pid)
+ goto out;
- ret = strict_strtol(buf, 10, &val);
- if (ret < 0)
- return ret;
+ ret = 0;
- mutex_lock(&ftrace_lock);
- if (val < 0) {
- /* disable pid tracing */
- if (!ftrace_pid_trace)
- goto out;
+ list_for_each_entry(fpid, &ftrace_pids, list)
+ if (fpid->pid == pid)
+ goto out_put;
- clear_ftrace_pid_task(&ftrace_pid_trace);
+ ret = -ENOMEM;
- } else {
- /* swapper task is special */
- if (!val) {
- pid = ftrace_swapper_pid;
- if (pid == ftrace_pid_trace)
- goto out;
- } else {
- pid = find_get_pid(val);
+ fpid = kmalloc(sizeof(*fpid), GFP_KERNEL);
+ if (!fpid)
+ goto out_put;
- if (pid == ftrace_pid_trace) {
- put_pid(pid);
- goto out;
- }
- }
+ list_add(&fpid->list, &ftrace_pids);
+ fpid->pid = pid;
- if (ftrace_pid_trace)
- clear_ftrace_pid_task(&ftrace_pid_trace);
+ set_ftrace_pid_task(pid);
- if (!pid)
- goto out;
+ ftrace_update_pid_func();
+ ftrace_startup_enable(0);
- ftrace_pid_trace = pid;
+ mutex_unlock(&ftrace_lock);
+ return 0;
+
+out_put:
+ if (pid != ftrace_swapper_pid)
+ put_pid(pid);
+
+out:
+ mutex_unlock(&ftrace_lock);
+ return ret;
+}
+
+static void ftrace_pid_reset(void)
+{
+ struct ftrace_pid *fpid, *safe;
- set_ftrace_pid_task(ftrace_pid_trace);
+ mutex_lock(&ftrace_lock);
+ list_for_each_entry_safe(fpid, safe, &ftrace_pids, list) {
+ struct pid *pid = fpid->pid;
+
+ clear_ftrace_pid_task(pid);
+
+ list_del(&fpid->list);
+ kfree(fpid);
}
- /* update the function call */
ftrace_update_pid_func();
ftrace_startup_enable(0);
- out:
mutex_unlock(&ftrace_lock);
+}
- return cnt;
+static void *fpid_start(struct seq_file *m, loff_t *pos)
+{
+ mutex_lock(&ftrace_lock);
+
+ if (list_empty(&ftrace_pids) && (!*pos))
+ return (void *) 1;
+
+ return seq_list_start(&ftrace_pids, *pos);
+}
+
+static void *fpid_next(struct seq_file *m, void *v, loff_t *pos)
+{
+ if (v == (void *)1)
+ return NULL;
+
+ return seq_list_next(v, &ftrace_pids, pos);
+}
+
+static void fpid_stop(struct seq_file *m, void *p)
+{
+ mutex_unlock(&ftrace_lock);
+}
+
+static int fpid_show(struct seq_file *m, void *v)
+{
+ const struct ftrace_pid *fpid = list_entry(v, struct ftrace_pid, list);
+
+ if (v == (void *)1) {
+ seq_printf(m, "no pid\n");
+ return 0;
+ }
+
+ if (fpid->pid == ftrace_swapper_pid)
+ seq_printf(m, "swapper tasks\n");
+ else
+ seq_printf(m, "%u\n", pid_vnr(fpid->pid));
+
+ return 0;
+}
+
+static const struct seq_operations ftrace_pid_sops = {
+ .start = fpid_start,
+ .next = fpid_next,
+ .stop = fpid_stop,
+ .show = fpid_show,
+};
+
+static int
+ftrace_pid_open(struct inode *inode, struct file *file)
+{
+ int ret = 0;
+
+ if ((file->f_mode & FMODE_WRITE) &&
+ (file->f_flags & O_TRUNC))
+ ftrace_pid_reset();
+
+ if (file->f_mode & FMODE_READ)
+ ret = seq_open(file, &ftrace_pid_sops);
+
+ return ret;
+}
+
+static ssize_t
+ftrace_pid_write(struct file *filp, const char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ char buf[64], *tmp;
+ long val;
+ int ret;
+
+ if (cnt >= sizeof(buf))
+ return -EINVAL;
+
+ if (copy_from_user(&buf, ubuf, cnt))
+ return -EFAULT;
+
+ buf[cnt] = 0;
+
+ /*
+ * Allow "echo > set_ftrace_pid" or "echo -n '' > set_ftrace_pid"
+ * to clean the filter quietly.
+ */
+ tmp = strstrip(buf);
+ if (strlen(tmp) == 0)
+ return 1;
+
+ ret = strict_strtol(tmp, 10, &val);
+ if (ret < 0)
+ return ret;
+
+ ret = ftrace_pid_add(val);
+
+ return ret ? ret : cnt;
+}
+
+static int
+ftrace_pid_release(struct inode *inode, struct file *file)
+{
+ if (file->f_mode & FMODE_READ)
+ seq_release(inode, file);
+
+ return 0;
}
static const struct file_operations ftrace_pid_fops = {
- .read = ftrace_pid_read,
- .write = ftrace_pid_write,
+ .open = ftrace_pid_open,
+ .write = ftrace_pid_write,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = ftrace_pid_release,
};
static __init int ftrace_init_debugfs(void)
int
ftrace_enable_sysctl(struct ctl_table *table, int write,
- struct file *file, void __user *buffer, size_t *lenp,
+ void __user *buffer, size_t *lenp,
loff_t *ppos)
{
int ret;
mutex_lock(&ftrace_lock);
- ret = proc_dointvec(table, write, file, buffer, lenp, ppos);
+ ret = proc_dointvec(table, write, buffer, lenp, ppos);
if (ret || !write || (last_ftrace_enabled == !!ftrace_enabled))
goto out;
}
static void
-ftrace_graph_probe_sched_switch(struct rq *__rq, struct task_struct *prev,
- struct task_struct *next)
+ftrace_graph_probe_sched_switch(void *ignore,
+ struct task_struct *prev, struct task_struct *next)
{
unsigned long long timestamp;
int index;
} while (ret == -EAGAIN);
if (!ret) {
- ret = register_trace_sched_switch(ftrace_graph_probe_sched_switch);
+ ret = register_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL);
if (ret)
pr_info("ftrace_graph: Couldn't activate tracepoint"
" probe to kernel_sched_switch\n");
goto out;
ftrace_graph_active--;
- unregister_trace_sched_switch(ftrace_graph_probe_sched_switch);
ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub;
ftrace_graph_entry = ftrace_graph_entry_stub;
ftrace_shutdown(FTRACE_STOP_FUNC_RET);
unregister_pm_notifier(&ftrace_suspend_notifier);
+ unregister_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL);
out:
mutex_unlock(&ftrace_lock);
{
/* Make sure we do not use the parent ret_stack */
t->ret_stack = NULL;
+ t->curr_ret_stack = -1;
if (ftrace_graph_active) {
struct ftrace_ret_stack *ret_stack;
GFP_KERNEL);
if (!ret_stack)
return;
- t->curr_ret_stack = -1;
atomic_set(&t->tracing_graph_pause, 0);
atomic_set(&t->trace_overrun, 0);
t->ftrace_timestamp = 0;
ftrace_stop();
}
#endif
-
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff