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-rw-r--r--kernel/trace/ftrace.c23
-rw-r--r--kernel/trace/trace.c49
-rw-r--r--kernel/trace/trace_events.c49
3 files changed, 35 insertions, 86 deletions
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index cc615f84751b..c71e91bf7372 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -2414,11 +2414,9 @@ 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 *
@@ -2482,16 +2480,10 @@ ftrace_graph_open(struct inode *inode, struct file *file)
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;
}
@@ -2560,7 +2552,6 @@ ftrace_graph_write(struct file *file, const char __user *ubuf,
size_t cnt, loff_t *ppos)
{
struct trace_parser parser;
- unsigned long *array;
size_t read = 0;
ssize_t ret;
@@ -2574,12 +2565,6 @@ ftrace_graph_write(struct file *file, const char __user *ubuf,
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;
@@ -2591,7 +2576,7 @@ ftrace_graph_write(struct file *file, const char __user *ubuf,
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;
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index fd52a19dd172..861308072d28 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -125,13 +125,13 @@ int ftrace_dump_on_oops;
static int tracing_set_tracer(const char *buf);
-#define BOOTUP_TRACER_SIZE 100
-static char bootup_tracer_buf[BOOTUP_TRACER_SIZE] __initdata;
+#define MAX_TRACER_SIZE 100
+static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata;
static char *default_bootup_tracer;
static int __init set_ftrace(char *str)
{
- strncpy(bootup_tracer_buf, str, BOOTUP_TRACER_SIZE);
+ strncpy(bootup_tracer_buf, str, MAX_TRACER_SIZE);
default_bootup_tracer = bootup_tracer_buf;
/* We are using ftrace early, expand it */
ring_buffer_expanded = 1;
@@ -242,13 +242,6 @@ static struct tracer *trace_types __read_mostly;
static struct tracer *current_trace __read_mostly;
/*
- * max_tracer_type_len is used to simplify the allocating of
- * buffers to read userspace tracer names. We keep track of
- * the longest tracer name registered.
- */
-static int max_tracer_type_len;
-
-/*
* trace_types_lock is used to protect the trace_types list.
* This lock is also used to keep user access serialized.
* Accesses from userspace will grab this lock while userspace
@@ -619,7 +612,6 @@ __releases(kernel_lock)
__acquires(kernel_lock)
{
struct tracer *t;
- int len;
int ret = 0;
if (!type->name) {
@@ -627,6 +619,11 @@ __acquires(kernel_lock)
return -1;
}
+ if (strlen(type->name) > MAX_TRACER_SIZE) {
+ pr_info("Tracer has a name longer than %d\n", MAX_TRACER_SIZE);
+ return -1;
+ }
+
/*
* When this gets called we hold the BKL which means that
* preemption is disabled. Various trace selftests however
@@ -641,7 +638,7 @@ __acquires(kernel_lock)
for (t = trace_types; t; t = t->next) {
if (strcmp(type->name, t->name) == 0) {
/* already found */
- pr_info("Trace %s already registered\n",
+ pr_info("Tracer %s already registered\n",
type->name);
ret = -1;
goto out;
@@ -692,9 +689,6 @@ __acquires(kernel_lock)
type->next = trace_types;
trace_types = type;
- len = strlen(type->name);
- if (len > max_tracer_type_len)
- max_tracer_type_len = len;
out:
tracing_selftest_running = false;
@@ -703,7 +697,7 @@ __acquires(kernel_lock)
if (ret || !default_bootup_tracer)
goto out_unlock;
- if (strncmp(default_bootup_tracer, type->name, BOOTUP_TRACER_SIZE))
+ if (strncmp(default_bootup_tracer, type->name, MAX_TRACER_SIZE))
goto out_unlock;
printk(KERN_INFO "Starting tracer '%s'\n", type->name);
@@ -725,14 +719,13 @@ __acquires(kernel_lock)
void unregister_tracer(struct tracer *type)
{
struct tracer **t;
- int len;
mutex_lock(&trace_types_lock);
for (t = &trace_types; *t; t = &(*t)->next) {
if (*t == type)
goto found;
}
- pr_info("Trace %s not registered\n", type->name);
+ pr_info("Tracer %s not registered\n", type->name);
goto out;
found:
@@ -745,17 +738,7 @@ void unregister_tracer(struct tracer *type)
current_trace->stop(&global_trace);
current_trace = &nop_trace;
}
-
- if (strlen(type->name) != max_tracer_type_len)
- goto out;
-
- max_tracer_type_len = 0;
- for (t = &trace_types; *t; t = &(*t)->next) {
- len = strlen((*t)->name);
- if (len > max_tracer_type_len)
- max_tracer_type_len = len;
- }
- out:
+out:
mutex_unlock(&trace_types_lock);
}
@@ -2604,7 +2587,7 @@ static ssize_t
tracing_set_trace_read(struct file *filp, char __user *ubuf,
size_t cnt, loff_t *ppos)
{
- char buf[max_tracer_type_len+2];
+ char buf[MAX_TRACER_SIZE+2];
int r;
mutex_lock(&trace_types_lock);
@@ -2754,15 +2737,15 @@ static ssize_t
tracing_set_trace_write(struct file *filp, const char __user *ubuf,
size_t cnt, loff_t *ppos)
{
- char buf[max_tracer_type_len+1];
+ char buf[MAX_TRACER_SIZE+1];
int i;
size_t ret;
int err;
ret = cnt;
- if (cnt > max_tracer_type_len)
- cnt = max_tracer_type_len;
+ if (cnt > MAX_TRACER_SIZE)
+ cnt = MAX_TRACER_SIZE;
if (copy_from_user(&buf, ubuf, cnt))
return -EFAULT;
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 56c260b83a9c..6f03c8a1105e 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -271,42 +271,32 @@ ftrace_event_write(struct file *file, const char __user *ubuf,
static void *
t_next(struct seq_file *m, void *v, loff_t *pos)
{
- struct list_head *list = m->private;
- struct ftrace_event_call *call;
+ struct ftrace_event_call *call = v;
(*pos)++;
- for (;;) {
- if (list == &ftrace_events)
- return NULL;
-
- call = list_entry(list, struct ftrace_event_call, list);
-
+ list_for_each_entry_continue(call, &ftrace_events, list) {
/*
* The ftrace subsystem is for showing formats only.
* They can not be enabled or disabled via the event files.
*/
if (call->regfunc)
- break;
-
- list = list->next;
+ return call;
}
- m->private = list->next;
-
- return call;
+ return NULL;
}
static void *t_start(struct seq_file *m, loff_t *pos)
{
- struct ftrace_event_call *call = NULL;
+ struct ftrace_event_call *call;
loff_t l;
mutex_lock(&event_mutex);
- m->private = ftrace_events.next;
+ call = list_entry(&ftrace_events, struct ftrace_event_call, list);
for (l = 0; l <= *pos; ) {
- call = t_next(m, NULL, &l);
+ call = t_next(m, call, &l);
if (!call)
break;
}
@@ -316,37 +306,28 @@ static void *t_start(struct seq_file *m, loff_t *pos)
static void *
s_next(struct seq_file *m, void *v, loff_t *pos)
{
- struct list_head *list = m->private;
- struct ftrace_event_call *call;
+ struct ftrace_event_call *call = v;
(*pos)++;
- retry:
- if (list == &ftrace_events)
- return NULL;
-
- call = list_entry(list, struct ftrace_event_call, list);
-
- if (!call->enabled) {
- list = list->next;
- goto retry;
+ list_for_each_entry_continue(call, &ftrace_events, list) {
+ if (call->enabled)
+ return call;
}
- m->private = list->next;
-
- return call;
+ return NULL;
}
static void *s_start(struct seq_file *m, loff_t *pos)
{
- struct ftrace_event_call *call = NULL;
+ struct ftrace_event_call *call;
loff_t l;
mutex_lock(&event_mutex);
- m->private = ftrace_events.next;
+ call = list_entry(&ftrace_events, struct ftrace_event_call, list);
for (l = 0; l <= *pos; ) {
- call = s_next(m, NULL, &l);
+ call = s_next(m, call, &l);
if (!call)
break;
}
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