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-rw-r--r--kernel/trace/ftrace.c359
-rw-r--r--kernel/trace/trace.c15
-rw-r--r--kernel/trace/trace_output.c3
-rw-r--r--kernel/trace/trace_printk.c120
4 files changed, 268 insertions, 229 deletions
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index ee24fa1935ac..d3406346ced6 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -39,16 +39,20 @@
#include "trace_stat.h"
#define FTRACE_WARN_ON(cond) \
- do { \
- if (WARN_ON(cond)) \
+ ({ \
+ int ___r = cond; \
+ if (WARN_ON(___r)) \
ftrace_kill(); \
- } while (0)
+ ___r; \
+ })
#define FTRACE_WARN_ON_ONCE(cond) \
- do { \
- if (WARN_ON_ONCE(cond)) \
+ ({ \
+ int ___r = cond; \
+ if (WARN_ON_ONCE(___r)) \
ftrace_kill(); \
- } while (0)
+ ___r; \
+ })
/* hash bits for specific function selection */
#define FTRACE_HASH_BITS 7
@@ -147,6 +151,34 @@ static void ftrace_test_stop_func(unsigned long ip, unsigned long parent_ip)
}
#endif
+static void update_ftrace_function(void)
+{
+ ftrace_func_t func;
+
+ /*
+ * If there's only one function registered, then call that
+ * function directly. Otherwise, we need to iterate over the
+ * registered callers.
+ */
+ if (ftrace_list == &ftrace_list_end ||
+ ftrace_list->next == &ftrace_list_end)
+ func = ftrace_list->func;
+ else
+ func = ftrace_list_func;
+
+ /* If we filter on pids, update to use the pid function */
+ if (!list_empty(&ftrace_pids)) {
+ set_ftrace_pid_function(func);
+ func = ftrace_pid_func;
+ }
+#ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST
+ ftrace_trace_function = func;
+#else
+ __ftrace_trace_function = func;
+ ftrace_trace_function = ftrace_test_stop_func;
+#endif
+}
+
static int __register_ftrace_function(struct ftrace_ops *ops)
{
ops->next = ftrace_list;
@@ -158,30 +190,8 @@ static int __register_ftrace_function(struct ftrace_ops *ops)
*/
rcu_assign_pointer(ftrace_list, ops);
- if (ftrace_enabled) {
- ftrace_func_t func;
-
- if (ops->next == &ftrace_list_end)
- func = ops->func;
- else
- func = ftrace_list_func;
-
- if (!list_empty(&ftrace_pids)) {
- set_ftrace_pid_function(func);
- func = ftrace_pid_func;
- }
-
- /*
- * For one func, simply call it directly.
- * For more than one func, call the chain.
- */
-#ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST
- ftrace_trace_function = func;
-#else
- __ftrace_trace_function = func;
- ftrace_trace_function = ftrace_test_stop_func;
-#endif
- }
+ if (ftrace_enabled)
+ update_ftrace_function();
return 0;
}
@@ -209,52 +219,19 @@ static int __unregister_ftrace_function(struct ftrace_ops *ops)
*p = (*p)->next;
- if (ftrace_enabled) {
- /* If we only have one func left, then call that directly */
- if (ftrace_list->next == &ftrace_list_end) {
- ftrace_func_t func = ftrace_list->func;
-
- if (!list_empty(&ftrace_pids)) {
- set_ftrace_pid_function(func);
- func = ftrace_pid_func;
- }
-#ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST
- ftrace_trace_function = func;
-#else
- __ftrace_trace_function = func;
-#endif
- }
- }
+ if (ftrace_enabled)
+ update_ftrace_function();
return 0;
}
static void ftrace_update_pid_func(void)
{
- ftrace_func_t func;
-
+ /* Only do something if we are tracing something */
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 (!list_empty(&ftrace_pids)) {
- set_ftrace_pid_function(func);
- func = ftrace_pid_func;
- } else {
- if (func == ftrace_pid_func)
- func = ftrace_pid_function;
- }
-
-#ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST
- ftrace_trace_function = func;
-#else
- __ftrace_trace_function = func;
-#endif
+ update_ftrace_function();
}
#ifdef CONFIG_FUNCTION_PROFILER
@@ -1079,19 +1056,16 @@ static void ftrace_replace_code(int enable)
struct ftrace_page *pg;
int failed;
+ if (unlikely(ftrace_disabled))
+ return;
+
do_for_each_ftrace_rec(pg, rec) {
- /*
- * Skip over free records, records that have
- * failed and not converted.
- */
- if (rec->flags & FTRACE_FL_FREE ||
- rec->flags & FTRACE_FL_FAILED ||
- !(rec->flags & FTRACE_FL_CONVERTED))
+ /* Skip over free records */
+ if (rec->flags & FTRACE_FL_FREE)
continue;
failed = __ftrace_replace_code(rec, enable);
if (failed) {
- rec->flags |= FTRACE_FL_FAILED;
ftrace_bug(failed, rec->ip);
/* Stop processing */
return;
@@ -1107,10 +1081,12 @@ ftrace_code_disable(struct module *mod, struct dyn_ftrace *rec)
ip = rec->ip;
+ if (unlikely(ftrace_disabled))
+ return 0;
+
ret = ftrace_make_nop(mod, rec, MCOUNT_ADDR);
if (ret) {
ftrace_bug(ret, ip);
- rec->flags |= FTRACE_FL_FAILED;
return 0;
}
return 1;
@@ -1273,10 +1249,10 @@ static int ftrace_update_code(struct module *mod)
*/
if (!ftrace_code_disable(mod, p)) {
ftrace_free_rec(p);
- continue;
+ /* Game over */
+ break;
}
- p->flags |= FTRACE_FL_CONVERTED;
ftrace_update_cnt++;
/*
@@ -1351,9 +1327,8 @@ static int __init ftrace_dyn_table_alloc(unsigned long num_to_init)
enum {
FTRACE_ITER_FILTER = (1 << 0),
FTRACE_ITER_NOTRACE = (1 << 1),
- FTRACE_ITER_FAILURES = (1 << 2),
- FTRACE_ITER_PRINTALL = (1 << 3),
- FTRACE_ITER_HASH = (1 << 4),
+ FTRACE_ITER_PRINTALL = (1 << 2),
+ FTRACE_ITER_HASH = (1 << 3),
};
#define FTRACE_BUFF_MAX (KSYM_SYMBOL_LEN+4) /* room for wildcards */
@@ -1463,6 +1438,9 @@ t_next(struct seq_file *m, void *v, loff_t *pos)
struct ftrace_iterator *iter = m->private;
struct dyn_ftrace *rec = NULL;
+ if (unlikely(ftrace_disabled))
+ return NULL;
+
if (iter->flags & FTRACE_ITER_HASH)
return t_hash_next(m, pos);
@@ -1483,12 +1461,6 @@ t_next(struct seq_file *m, void *v, loff_t *pos)
rec = &iter->pg->records[iter->idx++];
if ((rec->flags & FTRACE_FL_FREE) ||
- (!(iter->flags & FTRACE_ITER_FAILURES) &&
- (rec->flags & FTRACE_FL_FAILED)) ||
-
- ((iter->flags & FTRACE_ITER_FAILURES) &&
- !(rec->flags & FTRACE_FL_FAILED)) ||
-
((iter->flags & FTRACE_ITER_FILTER) &&
!(rec->flags & FTRACE_FL_FILTER)) ||
@@ -1521,6 +1493,10 @@ static void *t_start(struct seq_file *m, loff_t *pos)
loff_t l;
mutex_lock(&ftrace_lock);
+
+ if (unlikely(ftrace_disabled))
+ return NULL;
+
/*
* If an lseek was done, then reset and start from beginning.
*/
@@ -1629,24 +1605,6 @@ ftrace_avail_open(struct inode *inode, struct file *file)
return ret;
}
-static int
-ftrace_failures_open(struct inode *inode, struct file *file)
-{
- int ret;
- struct seq_file *m;
- struct ftrace_iterator *iter;
-
- ret = ftrace_avail_open(inode, file);
- if (!ret) {
- m = file->private_data;
- iter = m->private;
- iter->flags = FTRACE_ITER_FAILURES;
- }
-
- return ret;
-}
-
-
static void ftrace_filter_reset(int enable)
{
struct ftrace_page *pg;
@@ -1657,8 +1615,6 @@ static void ftrace_filter_reset(int enable)
if (enable)
ftrace_filtered = 0;
do_for_each_ftrace_rec(pg, rec) {
- if (rec->flags & FTRACE_FL_FAILED)
- continue;
rec->flags &= ~type;
} while_for_each_ftrace_rec();
mutex_unlock(&ftrace_lock);
@@ -1760,42 +1716,63 @@ static int ftrace_match(char *str, char *regex, int len, int type)
return matched;
}
+static void
+update_record(struct dyn_ftrace *rec, unsigned long flag, int not)
+{
+ if (not)
+ rec->flags &= ~flag;
+ else
+ rec->flags |= flag;
+}
+
static int
-ftrace_match_record(struct dyn_ftrace *rec, char *regex, int len, int type)
+ftrace_match_record(struct dyn_ftrace *rec, char *mod,
+ char *regex, int len, int type)
{
char str[KSYM_SYMBOL_LEN];
+ char *modname;
+
+ kallsyms_lookup(rec->ip, NULL, NULL, &modname, str);
+
+ if (mod) {
+ /* module lookup requires matching the module */
+ if (!modname || strcmp(modname, mod))
+ return 0;
+
+ /* blank search means to match all funcs in the mod */
+ if (!len)
+ return 1;
+ }
- kallsyms_lookup(rec->ip, NULL, NULL, NULL, str);
return ftrace_match(str, regex, len, type);
}
-static int ftrace_match_records(char *buff, int len, int enable)
+static int match_records(char *buff, int len, char *mod, int enable, int not)
{
- unsigned int search_len;
+ unsigned search_len = 0;
struct ftrace_page *pg;
struct dyn_ftrace *rec;
+ int type = MATCH_FULL;
+ char *search = buff;
unsigned long flag;
- char *search;
- int type;
- int not;
int found = 0;
- flag = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE;
- type = filter_parse_regex(buff, len, &search, &not);
+ if (len) {
+ type = filter_parse_regex(buff, len, &search, &not);
+ search_len = strlen(search);
+ }
- search_len = strlen(search);
+ flag = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE;
mutex_lock(&ftrace_lock);
- do_for_each_ftrace_rec(pg, rec) {
- if (rec->flags & FTRACE_FL_FAILED)
- continue;
+ if (unlikely(ftrace_disabled))
+ goto out_unlock;
- if (ftrace_match_record(rec, search, search_len, type)) {
- if (not)
- rec->flags &= ~flag;
- else
- rec->flags |= flag;
+ do_for_each_ftrace_rec(pg, rec) {
+
+ if (ftrace_match_record(rec, mod, search, search_len, type)) {
+ update_record(rec, flag, not);
found = 1;
}
/*
@@ -1804,43 +1781,23 @@ static int ftrace_match_records(char *buff, int len, int enable)
*/
if (enable && (rec->flags & FTRACE_FL_FILTER))
ftrace_filtered = 1;
+
} while_for_each_ftrace_rec();
+ out_unlock:
mutex_unlock(&ftrace_lock);
return found;
}
static int
-ftrace_match_module_record(struct dyn_ftrace *rec, char *mod,
- char *regex, int len, int type)
+ftrace_match_records(char *buff, int len, int enable)
{
- char str[KSYM_SYMBOL_LEN];
- char *modname;
-
- kallsyms_lookup(rec->ip, NULL, NULL, &modname, str);
-
- if (!modname || strcmp(modname, mod))
- return 0;
-
- /* blank search means to match all funcs in the mod */
- if (len)
- return ftrace_match(str, regex, len, type);
- else
- return 1;
+ return match_records(buff, len, NULL, enable, 0);
}
static int ftrace_match_module_records(char *buff, char *mod, int enable)
{
- unsigned search_len = 0;
- struct ftrace_page *pg;
- struct dyn_ftrace *rec;
- int type = MATCH_FULL;
- char *search = buff;
- unsigned long flag;
int not = 0;
- int found = 0;
-
- flag = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE;
/* blank or '*' mean the same */
if (strcmp(buff, "*") == 0)
@@ -1852,32 +1809,7 @@ static int ftrace_match_module_records(char *buff, char *mod, int enable)
not = 1;
}
- if (strlen(buff)) {
- type = filter_parse_regex(buff, strlen(buff), &search, &not);
- search_len = strlen(search);
- }
-
- mutex_lock(&ftrace_lock);
- do_for_each_ftrace_rec(pg, rec) {
-
- if (rec->flags & FTRACE_FL_FAILED)
- continue;
-
- if (ftrace_match_module_record(rec, mod,
- search, search_len, type)) {
- if (not)
- 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;
+ return match_records(buff, strlen(buff), mod, enable, not);
}
/*
@@ -2029,12 +1961,13 @@ register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
return -EINVAL;
mutex_lock(&ftrace_lock);
- do_for_each_ftrace_rec(pg, rec) {
- if (rec->flags & FTRACE_FL_FAILED)
- continue;
+ if (unlikely(ftrace_disabled))
+ goto out_unlock;
- if (!ftrace_match_record(rec, search, len, type))
+ do_for_each_ftrace_rec(pg, rec) {
+
+ if (!ftrace_match_record(rec, NULL, search, len, type))
continue;
entry = kmalloc(sizeof(*entry), GFP_KERNEL);
@@ -2239,6 +2172,10 @@ ftrace_regex_write(struct file *file, const char __user *ubuf,
mutex_lock(&ftrace_regex_lock);
+ ret = -ENODEV;
+ if (unlikely(ftrace_disabled))
+ goto out_unlock;
+
if (file->f_mode & FMODE_READ) {
struct seq_file *m = file->private_data;
iter = m->private;
@@ -2413,14 +2350,16 @@ ftrace_regex_release(struct inode *inode, struct file *file, int enable)
ftrace_match_records(parser->buffer, parser->idx, enable);
}
- mutex_lock(&ftrace_lock);
- if (ftrace_start_up && ftrace_enabled)
- ftrace_run_update_code(FTRACE_ENABLE_CALLS);
- mutex_unlock(&ftrace_lock);
-
trace_parser_put(parser);
kfree(iter);
+ if (file->f_mode & FMODE_WRITE) {
+ mutex_lock(&ftrace_lock);
+ if (ftrace_start_up && ftrace_enabled)
+ ftrace_run_update_code(FTRACE_ENABLE_CALLS);
+ mutex_unlock(&ftrace_lock);
+ }
+
mutex_unlock(&ftrace_regex_lock);
return 0;
}
@@ -2444,13 +2383,6 @@ static const struct file_operations ftrace_avail_fops = {
.release = seq_release_private,
};
-static const struct file_operations ftrace_failures_fops = {
- .open = ftrace_failures_open,
- .read = seq_read,
- .llseek = seq_lseek,
- .release = seq_release_private,
-};
-
static const struct file_operations ftrace_filter_fops = {
.open = ftrace_filter_open,
.read = seq_read,
@@ -2573,9 +2505,6 @@ ftrace_set_func(unsigned long *array, int *idx, char *buffer)
bool exists;
int i;
- if (ftrace_disabled)
- return -ENODEV;
-
/* decode regex */
type = filter_parse_regex(buffer, strlen(buffer), &search, &not);
if (!not && *idx >= FTRACE_GRAPH_MAX_FUNCS)
@@ -2584,12 +2513,18 @@ ftrace_set_func(unsigned long *array, int *idx, char *buffer)
search_len = strlen(search);
mutex_lock(&ftrace_lock);
+
+ if (unlikely(ftrace_disabled)) {
+ mutex_unlock(&ftrace_lock);
+ return -ENODEV;
+ }
+
do_for_each_ftrace_rec(pg, rec) {
- if (rec->flags & (FTRACE_FL_FAILED | FTRACE_FL_FREE))
+ if (rec->flags & FTRACE_FL_FREE)
continue;
- if (ftrace_match_record(rec, search, search_len, type)) {
+ if (ftrace_match_record(rec, NULL, search, search_len, type)) {
/* if it is in the array */
exists = false;
for (i = 0; i < *idx; i++) {
@@ -2679,9 +2614,6 @@ static __init int ftrace_init_dyn_debugfs(struct dentry *d_tracer)
trace_create_file("available_filter_functions", 0444,
d_tracer, NULL, &ftrace_avail_fops);
- trace_create_file("failures", 0444,
- d_tracer, NULL, &ftrace_failures_fops);
-
trace_create_file("set_ftrace_filter", 0644, d_tracer,
NULL, &ftrace_filter_fops);
@@ -2703,7 +2635,6 @@ static int ftrace_process_locs(struct module *mod,
{
unsigned long *p;
unsigned long addr;
- unsigned long flags;
mutex_lock(&ftrace_lock);
p = start;
@@ -2720,10 +2651,7 @@ static int ftrace_process_locs(struct module *mod,
ftrace_record_ip(addr);
}
- /* disable interrupts to prevent kstop machine */
- local_irq_save(flags);
ftrace_update_code(mod);
- local_irq_restore(flags);
mutex_unlock(&ftrace_lock);
return 0;
@@ -2735,10 +2663,11 @@ void ftrace_release_mod(struct module *mod)
struct dyn_ftrace *rec;
struct ftrace_page *pg;
+ mutex_lock(&ftrace_lock);
+
if (ftrace_disabled)
- return;
+ goto out_unlock;
- mutex_lock(&ftrace_lock);
do_for_each_ftrace_rec(pg, rec) {
if (within_module_core(rec->ip, mod)) {
/*
@@ -2749,6 +2678,7 @@ void ftrace_release_mod(struct module *mod)
ftrace_free_rec(rec);
}
} while_for_each_ftrace_rec();
+ out_unlock:
mutex_unlock(&ftrace_lock);
}
@@ -3143,16 +3073,17 @@ void ftrace_kill(void)
*/
int register_ftrace_function(struct ftrace_ops *ops)
{
- int ret;
-
- if (unlikely(ftrace_disabled))
- return -1;
+ int ret = -1;
mutex_lock(&ftrace_lock);
+ if (unlikely(ftrace_disabled))
+ goto out_unlock;
+
ret = __register_ftrace_function(ops);
ftrace_startup(0);
+ out_unlock:
mutex_unlock(&ftrace_lock);
return ret;
}
@@ -3180,14 +3111,14 @@ ftrace_enable_sysctl(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp,
loff_t *ppos)
{
- int ret;
-
- if (unlikely(ftrace_disabled))
- return -ENODEV;
+ int ret = -ENODEV;
mutex_lock(&ftrace_lock);
- ret = proc_dointvec(table, write, buffer, lenp, ppos);
+ if (unlikely(ftrace_disabled))
+ goto out;
+
+ ret = proc_dointvec(table, write, buffer, lenp, ppos);
if (ret || !write || (last_ftrace_enabled == !!ftrace_enabled))
goto out;
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 1cb49be7c7fb..ee9c921d7f21 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -2014,9 +2014,10 @@ enum print_line_t print_trace_line(struct trace_iterator *iter)
{
enum print_line_t ret;
- if (iter->lost_events)
- trace_seq_printf(&iter->seq, "CPU:%d [LOST %lu EVENTS]\n",
- iter->cpu, iter->lost_events);
+ if (iter->lost_events &&
+ !trace_seq_printf(&iter->seq, "CPU:%d [LOST %lu EVENTS]\n",
+ iter->cpu, iter->lost_events))
+ return TRACE_TYPE_PARTIAL_LINE;
if (iter->trace && iter->trace->print_line) {
ret = iter->trace->print_line(iter);
@@ -3230,6 +3231,14 @@ waitagain:
if (iter->seq.len >= cnt)
break;
+
+ /*
+ * Setting the full flag means we reached the trace_seq buffer
+ * size and we should leave by partial output condition above.
+ * One of the trace_seq_* functions is not used properly.
+ */
+ WARN_ONCE(iter->seq.full, "full flag set for trace type %d",
+ iter->ent->type);
}
trace_access_unlock(iter->cpu_file);
trace_event_read_unlock();
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index 456be9063c2d..cf535ccedc86 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -830,6 +830,9 @@ EXPORT_SYMBOL_GPL(unregister_ftrace_event);
enum print_line_t trace_nop_print(struct trace_iterator *iter, int flags,
struct trace_event *event)
{
+ if (!trace_seq_printf(&iter->seq, "type: %d\n", iter->ent->type))
+ return TRACE_TYPE_PARTIAL_LINE;
+
return TRACE_TYPE_HANDLED;
}
diff --git a/kernel/trace/trace_printk.c b/kernel/trace/trace_printk.c
index 2547d8813cf0..dff763b7baf1 100644
--- a/kernel/trace/trace_printk.c
+++ b/kernel/trace/trace_printk.c
@@ -32,7 +32,7 @@ static DEFINE_MUTEX(btrace_mutex);
struct trace_bprintk_fmt {
struct list_head list;
- char fmt[0];
+ const char *fmt;
};
static inline struct trace_bprintk_fmt *lookup_format(const char *fmt)
@@ -49,6 +49,7 @@ static
void hold_module_trace_bprintk_format(const char **start, const char **end)
{
const char **iter;
+ char *fmt;
mutex_lock(&btrace_mutex);
for (iter = start; iter < end; iter++) {
@@ -58,14 +59,18 @@ void hold_module_trace_bprintk_format(const char **start, const char **end)
continue;
}
- tb_fmt = kmalloc(offsetof(struct trace_bprintk_fmt, fmt)
- + strlen(*iter) + 1, GFP_KERNEL);
- if (tb_fmt) {
+ tb_fmt = kmalloc(sizeof(*tb_fmt), GFP_KERNEL);
+ if (tb_fmt)
+ fmt = kmalloc(strlen(*iter) + 1, GFP_KERNEL);
+ if (tb_fmt && fmt) {
list_add_tail(&tb_fmt->list, &trace_bprintk_fmt_list);
- strcpy(tb_fmt->fmt, *iter);
+ strcpy(fmt, *iter);
+ tb_fmt->fmt = fmt;
*iter = tb_fmt->fmt;
- } else
+ } else {
+ kfree(tb_fmt);
*iter = NULL;
+ }
}
mutex_unlock(&btrace_mutex);
}
@@ -84,6 +89,76 @@ static int module_trace_bprintk_format_notify(struct notifier_block *self,
return 0;
}
+/*
+ * The debugfs/tracing/printk_formats file maps the addresses with
+ * the ASCII formats that are used in the bprintk events in the
+ * buffer. For userspace tools to be able to decode the events from
+ * the buffer, they need to be able to map the address with the format.
+ *
+ * The addresses of the bprintk formats are in their own section
+ * __trace_printk_fmt. But for modules we copy them into a link list.
+ * The code to print the formats and their addresses passes around the
+ * address of the fmt string. If the fmt address passed into the seq
+ * functions is within the kernel core __trace_printk_fmt section, then
+ * it simply uses the next pointer in the list.
+ *
+ * When the fmt pointer is outside the kernel core __trace_printk_fmt
+ * section, then we need to read the link list pointers. The trick is
+ * we pass the address of the string to the seq function just like
+ * we do for the kernel core formats. To get back the structure that
+ * holds the format, we simply use containerof() and then go to the
+ * next format in the list.
+ */
+static const char **
+find_next_mod_format(int start_index, void *v, const char **fmt, loff_t *pos)
+{
+ struct trace_bprintk_fmt *mod_fmt;
+
+ if (list_empty(&trace_bprintk_fmt_list))
+ return NULL;
+
+ /*
+ * v will point to the address of the fmt record from t_next
+ * v will be NULL from t_start.
+ * If this is the first pointer or called from start
+ * then we need to walk the list.
+ */
+ if (!v || start_index == *pos) {
+ struct trace_bprintk_fmt *p;
+
+ /* search the module list */
+ list_for_each_entry(p, &trace_bprintk_fmt_list, list) {
+ if (start_index == *pos)
+ return &p->fmt;
+ start_index++;
+ }
+ /* pos > index */
+ return NULL;
+ }
+
+ /*
+ * v points to the address of the fmt field in the mod list
+ * structure that holds the module print format.
+ */
+ mod_fmt = container_of(v, typeof(*mod_fmt), fmt);
+ if (mod_fmt->list.next == &trace_bprintk_fmt_list)
+ return NULL;
+
+ mod_fmt = container_of(mod_fmt->list.next, typeof(*mod_fmt), list);
+
+ return &mod_fmt->fmt;
+}
+
+static void format_mod_start(void)
+{
+ mutex_lock(&btrace_mutex);
+}
+
+static void format_mod_stop(void)
+{
+ mutex_unlock(&btrace_mutex);
+}
+
#else /* !CONFIG_MODULES */
__init static int
module_trace_bprintk_format_notify(struct notifier_block *self,
@@ -91,6 +166,13 @@ module_trace_bprintk_format_notify(struct notifier_block *self,
{
return 0;
}
+static inline const char **
+find_next_mod_format(int start_index, void *v, const char **fmt, loff_t *pos)
+{
+ return NULL;
+}
+static inline void format_mod_start(void) { }
+static inline void format_mod_stop(void) { }
#endif /* CONFIG_MODULES */
@@ -153,20 +235,33 @@ int __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap)
}
EXPORT_SYMBOL_GPL(__ftrace_vprintk);
+static const char **find_next(void *v, loff_t *pos)
+{
+ const char **fmt = v;
+ int start_index;
+
+ if (!fmt)
+ fmt = __start___trace_bprintk_fmt + *pos;
+
+ start_index = __stop___trace_bprintk_fmt - __start___trace_bprintk_fmt;
+
+ if (*pos < start_index)
+ return fmt;
+
+ return find_next_mod_format(start_index, v, fmt, pos);
+}
+
static void *
t_start(struct seq_file *m, loff_t *pos)
{
- const char **fmt = __start___trace_bprintk_fmt + *pos;
-
- if ((unsigned long)fmt >= (unsigned long)__stop___trace_bprintk_fmt)
- return NULL;
- return fmt;
+ format_mod_start();
+ return find_next(NULL, pos);
}
static void *t_next(struct seq_file *m, void * v, loff_t *pos)
{
(*pos)++;
- return t_start(m, pos);
+ return find_next(v, pos);
}
static int t_show(struct seq_file *m, void *v)
@@ -205,6 +300,7 @@ static int t_show(struct seq_file *m, void *v)
static void t_stop(struct seq_file *m, void *p)
{
+ format_mod_stop();
}
static const struct seq_operations show_format_seq_ops = {
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-18 06:12:00 +0000