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-rw-r--r--include/linux/ftrace.h4
-rw-r--r--include/linux/ftrace_event.h1
-rw-r--r--kernel/trace/Kconfig2
-rw-r--r--kernel/trace/ftrace.c126
-rw-r--r--kernel/trace/trace_events.c54
-rw-r--r--kernel/trace/trace_kprobe.c289
6 files changed, 368 insertions, 108 deletions
diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h
index f83e17a..99d0fbc 100644
--- a/include/linux/ftrace.h
+++ b/include/linux/ftrace.h
@@ -90,6 +90,8 @@ typedef void (*ftrace_func_t)(unsigned long ip, unsigned long parent_ip,
* not set this, then the ftrace infrastructure will add recursion
* protection for the caller.
* STUB - The ftrace_ops is just a place holder.
+ * INITIALIZED - The ftrace_ops has already been initialized (first use time
+ * register_ftrace_function() is called, it will initialized the ops)
*/
enum {
FTRACE_OPS_FL_ENABLED = 1 << 0,
@@ -100,6 +102,7 @@ enum {
FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED = 1 << 5,
FTRACE_OPS_FL_RECURSION_SAFE = 1 << 6,
FTRACE_OPS_FL_STUB = 1 << 7,
+ FTRACE_OPS_FL_INITIALIZED = 1 << 8,
};
struct ftrace_ops {
@@ -110,6 +113,7 @@ struct ftrace_ops {
#ifdef CONFIG_DYNAMIC_FTRACE
struct ftrace_hash *notrace_hash;
struct ftrace_hash *filter_hash;
+ struct mutex regex_lock;
#endif
};
diff --git a/include/linux/ftrace_event.h b/include/linux/ftrace_event.h
index 34e00fb..4372658 100644
--- a/include/linux/ftrace_event.h
+++ b/include/linux/ftrace_event.h
@@ -293,6 +293,7 @@ struct ftrace_event_file {
* caching and such. Which is mostly OK ;-)
*/
unsigned long flags;
+ atomic_t sm_ref; /* soft-mode reference counter */
};
#define __TRACE_EVENT_FLAGS(name, value) \
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index 5e9efd4..015f85a 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -71,6 +71,7 @@ config TRACE_CLOCK
config RING_BUFFER
bool
select TRACE_CLOCK
+ select IRQ_WORK
config FTRACE_NMI_ENTER
bool
@@ -107,7 +108,6 @@ config TRACING
select BINARY_PRINTF
select EVENT_TRACING
select TRACE_CLOCK
- select IRQ_WORK
config GENERIC_TRACER
bool
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 8a5c017..b549b0f 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -64,6 +64,13 @@
#define FL_GLOBAL_CONTROL_MASK (FTRACE_OPS_FL_GLOBAL | FTRACE_OPS_FL_CONTROL)
+#ifdef CONFIG_DYNAMIC_FTRACE
+#define INIT_REGEX_LOCK(opsname) \
+ .regex_lock = __MUTEX_INITIALIZER(opsname.regex_lock),
+#else
+#define INIT_REGEX_LOCK(opsname)
+#endif
+
static struct ftrace_ops ftrace_list_end __read_mostly = {
.func = ftrace_stub,
.flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_STUB,
@@ -131,6 +138,16 @@ static void ftrace_ops_no_ops(unsigned long ip, unsigned long parent_ip);
while (likely(op = rcu_dereference_raw((op)->next)) && \
unlikely((op) != &ftrace_list_end))
+static inline void ftrace_ops_init(struct ftrace_ops *ops)
+{
+#ifdef CONFIG_DYNAMIC_FTRACE
+ if (!(ops->flags & FTRACE_OPS_FL_INITIALIZED)) {
+ mutex_init(&ops->regex_lock);
+ ops->flags |= FTRACE_OPS_FL_INITIALIZED;
+ }
+#endif
+}
+
/**
* ftrace_nr_registered_ops - return number of ops registered
*
@@ -907,7 +924,8 @@ static void unregister_ftrace_profiler(void)
#else
static struct ftrace_ops ftrace_profile_ops __read_mostly = {
.func = function_profile_call,
- .flags = FTRACE_OPS_FL_RECURSION_SAFE,
+ .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_INITIALIZED,
+ INIT_REGEX_LOCK(ftrace_profile_ops)
};
static int register_ftrace_profiler(void)
@@ -1103,11 +1121,10 @@ static struct ftrace_ops global_ops = {
.func = ftrace_stub,
.notrace_hash = EMPTY_HASH,
.filter_hash = EMPTY_HASH,
- .flags = FTRACE_OPS_FL_RECURSION_SAFE,
+ .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_INITIALIZED,
+ INIT_REGEX_LOCK(global_ops)
};
-static DEFINE_MUTEX(ftrace_regex_lock);
-
struct ftrace_page {
struct ftrace_page *next;
struct dyn_ftrace *records;
@@ -1247,6 +1264,7 @@ static void free_ftrace_hash_rcu(struct ftrace_hash *hash)
void ftrace_free_filter(struct ftrace_ops *ops)
{
+ ftrace_ops_init(ops);
free_ftrace_hash(ops->filter_hash);
free_ftrace_hash(ops->notrace_hash);
}
@@ -2441,7 +2459,7 @@ t_next(struct seq_file *m, void *v, loff_t *pos)
!ftrace_lookup_ip(ops->notrace_hash, rec->ip)) ||
((iter->flags & FTRACE_ITER_ENABLED) &&
- !(rec->flags & ~FTRACE_FL_MASK))) {
+ !(rec->flags & FTRACE_FL_ENABLED))) {
rec = NULL;
goto retry;
@@ -2624,6 +2642,8 @@ ftrace_regex_open(struct ftrace_ops *ops, int flag,
struct ftrace_hash *hash;
int ret = 0;
+ ftrace_ops_init(ops);
+
if (unlikely(ftrace_disabled))
return -ENODEV;
@@ -2636,28 +2656,26 @@ ftrace_regex_open(struct ftrace_ops *ops, int flag,
return -ENOMEM;
}
+ iter->ops = ops;
+ iter->flags = flag;
+
+ mutex_lock(&ops->regex_lock);
+
if (flag & FTRACE_ITER_NOTRACE)
hash = ops->notrace_hash;
else
hash = ops->filter_hash;
- iter->ops = ops;
- iter->flags = flag;
-
if (file->f_mode & FMODE_WRITE) {
- mutex_lock(&ftrace_lock);
iter->hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, hash);
- mutex_unlock(&ftrace_lock);
-
if (!iter->hash) {
trace_parser_put(&iter->parser);
kfree(iter);
- return -ENOMEM;
+ ret = -ENOMEM;
+ goto out_unlock;
}
}
- mutex_lock(&ftrace_regex_lock);
-
if ((file->f_mode & FMODE_WRITE) &&
(file->f_flags & O_TRUNC))
ftrace_filter_reset(iter->hash);
@@ -2677,7 +2695,9 @@ ftrace_regex_open(struct ftrace_ops *ops, int flag,
}
} else
file->private_data = iter;
- mutex_unlock(&ftrace_regex_lock);
+
+ out_unlock:
+ mutex_unlock(&ops->regex_lock);
return ret;
}
@@ -2910,6 +2930,8 @@ static void function_trace_probe_call(unsigned long ip, unsigned long parent_ip,
static struct ftrace_ops trace_probe_ops __read_mostly =
{
.func = function_trace_probe_call,
+ .flags = FTRACE_OPS_FL_INITIALIZED,
+ INIT_REGEX_LOCK(trace_probe_ops)
};
static int ftrace_probe_registered;
@@ -2919,8 +2941,12 @@ static void __enable_ftrace_function_probe(void)
int ret;
int i;
- if (ftrace_probe_registered)
+ if (ftrace_probe_registered) {
+ /* still need to update the function call sites */
+ if (ftrace_enabled)
+ ftrace_run_update_code(FTRACE_UPDATE_CALLS);
return;
+ }
for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) {
struct hlist_head *hhd = &ftrace_func_hash[i];
@@ -2990,19 +3016,21 @@ register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
if (WARN_ON(not))
return -EINVAL;
- mutex_lock(&ftrace_lock);
+ mutex_lock(&trace_probe_ops.regex_lock);
hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, *orig_hash);
if (!hash) {
count = -ENOMEM;
- goto out_unlock;
+ goto out;
}
if (unlikely(ftrace_disabled)) {
count = -ENODEV;
- goto out_unlock;
+ goto out;
}
+ mutex_lock(&ftrace_lock);
+
do_for_each_ftrace_rec(pg, rec) {
if (!ftrace_match_record(rec, NULL, search, len, type))
@@ -3056,6 +3084,8 @@ register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
out_unlock:
mutex_unlock(&ftrace_lock);
+ out:
+ mutex_unlock(&trace_probe_ops.regex_lock);
free_ftrace_hash(hash);
return count;
@@ -3095,7 +3125,7 @@ __unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
return;
}
- mutex_lock(&ftrace_lock);
+ mutex_lock(&trace_probe_ops.regex_lock);
hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, *orig_hash);
if (!hash)
@@ -3133,6 +3163,7 @@ __unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
list_add(&entry->free_list, &free_list);
}
}
+ mutex_lock(&ftrace_lock);
__disable_ftrace_function_probe();
/*
* Remove after the disable is called. Otherwise, if the last
@@ -3144,9 +3175,10 @@ __unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
list_del(&entry->free_list);
ftrace_free_entry(entry);
}
+ mutex_unlock(&ftrace_lock);
out_unlock:
- mutex_unlock(&ftrace_lock);
+ mutex_unlock(&trace_probe_ops.regex_lock);
free_ftrace_hash(hash);
}
@@ -3256,18 +3288,17 @@ ftrace_regex_write(struct file *file, const char __user *ubuf,
if (!cnt)
return 0;
- 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;
} else
iter = file->private_data;
+ if (unlikely(ftrace_disabled))
+ return -ENODEV;
+
+ /* iter->hash is a local copy, so we don't need regex_lock */
+
parser = &iter->parser;
read = trace_get_user(parser, ubuf, cnt, ppos);
@@ -3276,14 +3307,12 @@ ftrace_regex_write(struct file *file, const char __user *ubuf,
ret = ftrace_process_regex(iter->hash, parser->buffer,
parser->idx, enable);
trace_parser_clear(parser);
- if (ret)
- goto out_unlock;
+ if (ret < 0)
+ goto out;
}
ret = read;
-out_unlock:
- mutex_unlock(&ftrace_regex_lock);
-
+ out:
return ret;
}
@@ -3335,16 +3364,19 @@ ftrace_set_hash(struct ftrace_ops *ops, unsigned char *buf, int len,
if (unlikely(ftrace_disabled))
return -ENODEV;
+ mutex_lock(&ops->regex_lock);
+
if (enable)
orig_hash = &ops->filter_hash;
else
orig_hash = &ops->notrace_hash;
hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, *orig_hash);
- if (!hash)
- return -ENOMEM;
+ if (!hash) {
+ ret = -ENOMEM;
+ goto out_regex_unlock;
+ }
- mutex_lock(&ftrace_regex_lock);
if (reset)
ftrace_filter_reset(hash);
if (buf && !ftrace_match_records(hash, buf, len)) {
@@ -3366,7 +3398,7 @@ ftrace_set_hash(struct ftrace_ops *ops, unsigned char *buf, int len,
mutex_unlock(&ftrace_lock);
out_regex_unlock:
- mutex_unlock(&ftrace_regex_lock);
+ mutex_unlock(&ops->regex_lock);
free_ftrace_hash(hash);
return ret;
@@ -3392,6 +3424,7 @@ ftrace_set_addr(struct ftrace_ops *ops, unsigned long ip, int remove,
int ftrace_set_filter_ip(struct ftrace_ops *ops, unsigned long ip,
int remove, int reset)
{
+ ftrace_ops_init(ops);
return ftrace_set_addr(ops, ip, remove, reset, 1);
}
EXPORT_SYMBOL_GPL(ftrace_set_filter_ip);
@@ -3416,6 +3449,7 @@ ftrace_set_regex(struct ftrace_ops *ops, unsigned char *buf, int len,
int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,
int len, int reset)
{
+ ftrace_ops_init(ops);
return ftrace_set_regex(ops, buf, len, reset, 1);
}
EXPORT_SYMBOL_GPL(ftrace_set_filter);
@@ -3434,6 +3468,7 @@ EXPORT_SYMBOL_GPL(ftrace_set_filter);
int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
int len, int reset)
{
+ ftrace_ops_init(ops);
return ftrace_set_regex(ops, buf, len, reset, 0);
}
EXPORT_SYMBOL_GPL(ftrace_set_notrace);
@@ -3524,6 +3559,8 @@ ftrace_set_early_filter(struct ftrace_ops *ops, char *buf, int enable)
{
char *func;
+ ftrace_ops_init(ops);
+
while (buf) {
func = strsep(&buf, ",");
ftrace_set_regex(ops, func, strlen(func), 0, enable);
@@ -3551,10 +3588,8 @@ int ftrace_regex_release(struct inode *inode, struct file *file)
int filter_hash;
int ret;
- mutex_lock(&ftrace_regex_lock);
if (file->f_mode & FMODE_READ) {
iter = m->private;
-
seq_release(inode, file);
} else
iter = file->private_data;
@@ -3567,6 +3602,8 @@ int ftrace_regex_release(struct inode *inode, struct file *file)
trace_parser_put(parser);
+ mutex_lock(&iter->ops->regex_lock);
+
if (file->f_mode & FMODE_WRITE) {
filter_hash = !!(iter->flags & FTRACE_ITER_FILTER);
@@ -3584,10 +3621,11 @@ int ftrace_regex_release(struct inode *inode, struct file *file)
mutex_unlock(&ftrace_lock);
}
+
+ mutex_unlock(&iter->ops->regex_lock);
free_ftrace_hash(iter->hash);
kfree(iter);
- mutex_unlock(&ftrace_regex_lock);
return 0;
}
@@ -4126,7 +4164,8 @@ void __init ftrace_init(void)
static struct ftrace_ops global_ops = {
.func = ftrace_stub,
- .flags = FTRACE_OPS_FL_RECURSION_SAFE,
+ .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_INITIALIZED,
+ INIT_REGEX_LOCK(global_ops)
};
static int __init ftrace_nodyn_init(void)
@@ -4180,8 +4219,9 @@ ftrace_ops_control_func(unsigned long ip, unsigned long parent_ip,
}
static struct ftrace_ops control_ops = {
- .func = ftrace_ops_control_func,
- .flags = FTRACE_OPS_FL_RECURSION_SAFE,
+ .func = ftrace_ops_control_func,
+ .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_INITIALIZED,
+ INIT_REGEX_LOCK(control_ops)
};
static inline void
@@ -4539,6 +4579,8 @@ int register_ftrace_function(struct ftrace_ops *ops)
{
int ret = -1;
+ ftrace_ops_init(ops);
+
mutex_lock(&ftrace_lock);
ret = __register_ftrace_function(ops);
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 53582e9..7a0cf68 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -251,7 +251,8 @@ static int __ftrace_event_enable_disable(struct ftrace_event_file *file,
switch (enable) {
case 0:
/*
- * When soft_disable is set and enable is cleared, we want
+ * When soft_disable is set and enable is cleared, the sm_ref
+ * reference counter is decremented. If it reaches 0, we want
* to clear the SOFT_DISABLED flag but leave the event in the
* state that it was. That is, if the event was enabled and
* SOFT_DISABLED isn't set, then do nothing. But if SOFT_DISABLED
@@ -263,6 +264,8 @@ static int __ftrace_event_enable_disable(struct ftrace_event_file *file,
* "soft enable"s (clearing the SOFT_DISABLED bit) wont work.
*/
if (soft_disable) {
+ if (atomic_dec_return(&file->sm_ref) > 0)
+ break;
disable = file->flags & FTRACE_EVENT_FL_SOFT_DISABLED;
clear_bit(FTRACE_EVENT_FL_SOFT_MODE_BIT, &file->flags);
} else
@@ -291,8 +294,11 @@ static int __ftrace_event_enable_disable(struct ftrace_event_file *file,
*/
if (!soft_disable)
clear_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &file->flags);
- else
+ else {
+ if (atomic_inc_return(&file->sm_ref) > 1)
+ break;
set_bit(FTRACE_EVENT_FL_SOFT_MODE_BIT, &file->flags);
+ }
if (!(file->flags & FTRACE_EVENT_FL_ENABLED)) {
@@ -623,6 +629,8 @@ event_enable_read(struct file *filp, char __user *ubuf, size_t cnt,
if (file->flags & FTRACE_EVENT_FL_ENABLED) {
if (file->flags & FTRACE_EVENT_FL_SOFT_DISABLED)
buf = "0*\n";
+ else if (file->flags & FTRACE_EVENT_FL_SOFT_MODE)
+ buf = "1*\n";
else
buf = "1\n";
} else
@@ -1521,6 +1529,24 @@ __register_event(struct ftrace_event_call *call, struct module *mod)
return 0;
}
+static struct ftrace_event_file *
+trace_create_new_event(struct ftrace_event_call *call,
+ struct trace_array *tr)
+{
+ struct ftrace_event_file *file;
+
+ file = kmem_cache_alloc(file_cachep, GFP_TRACE);
+ if (!file)
+ return NULL;
+
+ file->event_call = call;
+ file->tr = tr;
+ atomic_set(&file->sm_ref, 0);
+ list_add(&file->list, &tr->events);
+
+ return file;
+}
+
/* Add an event to a trace directory */
static int
__trace_add_new_event(struct ftrace_event_call *call,
@@ -1532,14 +1558,10 @@ __trace_add_new_event(struct ftrace_event_call *call,
{
struct ftrace_event_file *file;
- file = kmem_cache_alloc(file_cachep, GFP_TRACE);
+ file = trace_create_new_event(call, tr);
if (!file)
return -ENOMEM;
- file->event_call = call;
- file->tr = tr;
- list_add(&file->list, &tr->events);
-
return event_create_dir(tr->event_dir, file, id, enable, filter, format);
}
@@ -1554,14 +1576,10 @@ __trace_early_add_new_event(struct ftrace_event_call *call,
{
struct ftrace_event_file *file;
- file = kmem_cache_alloc(file_cachep, GFP_TRACE);
+ file = trace_create_new_event(call, tr);
if (!file)
return -ENOMEM;
- file->event_call = call;
- file->tr = tr;
- list_add(&file->list, &tr->events);
-
return 0;
}
@@ -2061,8 +2079,18 @@ event_enable_func(struct ftrace_hash *hash,
if (ret < 0)
goto out_put;
ret = register_ftrace_function_probe(glob, ops, data);
- if (!ret)
+ /*
+ * The above returns on success the # of functions enabled,
+ * but if it didn't find any functions it returns zero.
+ * Consider no functions a failure too.
+ */
+ if (!ret) {
+ ret = -ENOENT;
+ goto out_disable;
+ } else if (ret < 0)
goto out_disable;
+ /* Just return zero, not the number of enabled functions */
+ ret = 0;
out:
mutex_unlock(&event_mutex);
return ret;
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index 1865d5f..636d45f 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -27,7 +27,6 @@
/**
* Kprobe event core functions
*/
-
struct trace_probe {
struct list_head list;
struct kretprobe rp; /* Use rp.kp for kprobe use */
@@ -36,6 +35,7 @@ struct trace_probe {
const char *symbol; /* symbol name */
struct ftrace_event_class class;
struct ftrace_event_call call;
+ struct ftrace_event_file **files;
ssize_t size; /* trace entry size */
unsigned int nr_args;
struct probe_arg args[];
@@ -46,7 +46,7 @@ struct trace_probe {
(sizeof(struct probe_arg) * (n)))
-static __kprobes int trace_probe_is_return(struct trace_probe *tp)
+static __kprobes bool trace_probe_is_return(struct trace_probe *tp)
{
return tp->rp.handler != NULL;
}
@@ -183,12 +183,57 @@ static struct trace_probe *find_trace_probe(const char *event,
return NULL;
}
-/* Enable trace_probe - @flag must be TP_FLAG_TRACE or TP_FLAG_PROFILE */
-static int enable_trace_probe(struct trace_probe *tp, int flag)
+static int trace_probe_nr_files(struct trace_probe *tp)
+{
+ struct ftrace_event_file **file = tp->files;
+ int ret = 0;
+
+ if (file)
+ while (*(file++))
+ ret++;
+
+ return ret;
+}
+
+static DEFINE_MUTEX(probe_enable_lock);
+
+/*
+ * Enable trace_probe
+ * if the file is NULL, enable "perf" handler, or enable "trace" handler.
+ */
+static int
+enable_trace_probe(struct trace_probe *tp, struct ftrace_event_file *file)
{
int ret = 0;
- tp->flags |= flag;
+ mutex_lock(&probe_enable_lock);
+
+ if (file) {
+ struct ftrace_event_file **new, **old = tp->files;
+ int n = trace_probe_nr_files(tp);
+
+ /* 1 is for new one and 1 is for stopper */
+ new = kzalloc((n + 2) * sizeof(struct ftrace_event_file *),
+ GFP_KERNEL);
+ if (!new) {
+ ret = -ENOMEM;
+ goto out_unlock;
+ }
+ memcpy(new, old, n * sizeof(struct ftrace_event_file *));
+ new[n] = file;
+ /* The last one keeps a NULL */
+
+ rcu_assign_pointer(tp->files, new);
+ tp->flags |= TP_FLAG_TRACE;
+
+ if (old) {
+ /* Make sure the probe is done with old files */
+ synchronize_sched();
+ kfree(old);
+ }
+ } else
+ tp->flags |= TP_FLAG_PROFILE;
+
if (trace_probe_is_enabled(tp) && trace_probe_is_registered(tp) &&
!trace_probe_has_gone(tp)) {
if (trace_probe_is_return(tp))
@@ -197,19 +242,83 @@ static int enable_trace_probe(struct trace_probe *tp, int flag)
ret = enable_kprobe(&tp->rp.kp);
}
+ out_unlock:
+ mutex_unlock(&probe_enable_lock);
+
return ret;
}
-/* Disable trace_probe - @flag must be TP_FLAG_TRACE or TP_FLAG_PROFILE */
-static void disable_trace_probe(struct trace_probe *tp, int flag)
+static int
+trace_probe_file_index(struct trace_probe *tp, struct ftrace_event_file *file)
+{
+ int i;
+
+ if (tp->files) {
+ for (i = 0; tp->files[i]; i++)
+ if (tp->files[i] == file)
+ return i;
+ }
+
+ return -1;
+}
+
+/*
+ * Disable trace_probe
+ * if the file is NULL, disable "perf" handler, or disable "trace" handler.
+ */
+static int
+disable_trace_probe(struct trace_probe *tp, struct ftrace_event_file *file)
{
- tp->flags &= ~flag;
+ int ret = 0;
+
+ mutex_lock(&probe_enable_lock);
+
+ if (file) {
+ struct ftrace_event_file **new, **old = tp->files;
+ int n = trace_probe_nr_files(tp);
+ int i, j;
+
+ if (n == 0 || trace_probe_file_index(tp, file) < 0) {
+ ret = -EINVAL;
+ goto out_unlock;
+ }
+
+ if (n == 1) { /* Remove the last file */
+ tp->flags &= ~TP_FLAG_TRACE;
+ new = NULL;
+ } else {
+ new = kzalloc(n * sizeof(struct ftrace_event_file *),
+ GFP_KERNEL);
+ if (!new) {
+ ret = -ENOMEM;
+ goto out_unlock;
+ }
+
+ /* This copy & check loop copies the NULL stopper too */
+ for (i = 0, j = 0; j < n && i < n + 1; i++)
+ if (old[i] != file)
+ new[j++] = old[i];
+ }
+
+ rcu_assign_pointer(tp->files, new);
+
+ /* Make sure the probe is done with old files */
+ synchronize_sched();
+ kfree(old);
+ } else
+ tp->flags &= ~TP_FLAG_PROFILE;
+
if (!trace_probe_is_enabled(tp) && trace_probe_is_registered(tp)) {
if (trace_probe_is_return(tp))
disable_kretprobe(&tp->rp);
else
disable_kprobe(&tp->rp.kp);
}
+
+ out_unlock:
+ mutex_unlock(&probe_enable_lock);
+
+ return ret;
}
/* Internal register function - just handle k*probes and flags */
@@ -723,9 +832,10 @@ static __kprobes void store_trace_args(int ent_size, struct trace_probe *tp,
}
/* Kprobe handler */
-static __kprobes void kprobe_trace_func(struct kprobe *kp, struct pt_regs *regs)
+static __kprobes void
+__kprobe_trace_func(struct trace_probe *tp, struct pt_regs *regs,
+ struct ftrace_event_file *ftrace_file)
{
- struct trace_probe *tp = container_of(kp, struct trace_probe, rp.kp);
struct kprobe_trace_entry_head *entry;
struct ring_buffer_event *event;
struct ring_buffer *buffer;
@@ -733,7 +843,10 @@ static __kprobes void kprobe_trace_func(struct kprobe *kp, struct pt_regs *regs)
unsigned long irq_flags;
struct ftrace_event_call *call = &tp->call;
- tp->nhit++;
+ WARN_ON(call != ftrace_file->event_call);
+
+ if (test_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &ftrace_file->flags))
+ return;
local_save_flags(irq_flags);
pc = preempt_count();
@@ -741,13 +854,14 @@ static __kprobes void kprobe_trace_func(struct kprobe *kp, struct pt_regs *regs)
dsize = __get_data_size(tp, regs);
size = sizeof(*entry) + tp->size + dsize;
- event = trace_current_buffer_lock_reserve(&buffer, call->event.type,
- size, irq_flags, pc);
+ event = trace_event_buffer_lock_reserve(&buffer, ftrace_file,
+ call->event.type,
+ size, irq_flags, pc);
if (!event)
return;
entry = ring_buffer_event_data(event);
- entry->ip = (unsigned long)kp->addr;
+ entry->ip = (unsigned long)tp->rp.kp.addr;
store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize);
if (!filter_current_check_discard(buffer, call, entry, event))
@@ -755,11 +869,24 @@ static __kprobes void kprobe_trace_func(struct kprobe *kp, struct pt_regs *regs)
irq_flags, pc, regs);
}
+static __kprobes void
+kprobe_trace_func(struct trace_probe *tp, struct pt_regs *regs)
+{
+ struct ftrace_event_file **file = tp->files;
+
+ /* Note: preempt is already disabled around the kprobe handler */
+ while (*file) {
+ __kprobe_trace_func(tp, regs, *file);
+ file++;
+ }
+}
+
/* Kretprobe handler */
-static __kprobes void kretprobe_trace_func(struct kretprobe_instance *ri,
- struct pt_regs *regs)
+static __kprobes void
+__kretprobe_trace_func(struct trace_probe *tp, struct kretprobe_instance *ri,
+ struct pt_regs *regs,
+ struct ftrace_event_file *ftrace_file)
{
- struct trace_probe *tp = container_of(ri->rp, struct trace_probe, rp);
struct kretprobe_trace_entry_head *entry;
struct ring_buffer_event *event;
struct ring_buffer *buffer;
@@ -767,14 +894,20 @@ static __kprobes void kretprobe_trace_func(struct kretprobe_instance *ri,
unsigned long irq_flags;
struct ftrace_event_call *call = &tp->call;
+ WARN_ON(call != ftrace_file->event_call);
+
+ if (test_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &ftrace_file->flags))
+ return;
+
local_save_flags(irq_flags);
pc = preempt_count();
dsize = __get_data_size(tp, regs);
size = sizeof(*entry) + tp->size + dsize;
- event = trace_current_buffer_lock_reserve(&buffer, call->event.type,
- size, irq_flags, pc);
+ event = trace_event_buffer_lock_reserve(&buffer, ftrace_file,
+ call->event.type,
+ size, irq_flags, pc);
if (!event)
return;
@@ -788,6 +921,19 @@ static __kprobes void kretprobe_trace_func(struct kretprobe_instance *ri,
irq_flags, pc, regs);
}
+static __kprobes void
+kretprobe_trace_func(struct trace_probe *tp, struct kretprobe_instance *ri,
+ struct pt_regs *regs)
+{
+ struct ftrace_event_file **file = tp->files;
+
+ /* Note: preempt is already disabled around the kprobe handler */
+ while (*file) {
+ __kretprobe_trace_func(tp, ri, regs, *file);
+ file++;
+ }
+}
+
/* Event entry printers */
enum print_line_t
print_kprobe_event(struct trace_iterator *iter, int flags,
@@ -975,10 +1121,9 @@ static int set_print_fmt(struct trace_probe *tp)
#ifdef CONFIG_PERF_EVENTS
/* Kprobe profile handler */
-static __kprobes void kprobe_perf_func(struct kprobe *kp,
- struct pt_regs *regs)
+static __kprobes void
+kprobe_perf_func(struct trace_probe *tp, struct pt_regs *regs)
{
- struct trace_probe *tp = container_of(kp, struct trace_probe, rp.kp);
struct ftrace_event_call *call = &tp->call;
struct kprobe_trace_entry_head *entry;
struct hlist_head *head;
@@ -997,7 +1142,7 @@ static __kprobes void kprobe_perf_func(struct kprobe *kp,
if (!entry)
return;
- entry->ip = (unsigned long)kp->addr;
+ entry->ip = (unsigned long)tp->rp.kp.addr;
memset(&entry[1], 0, dsize);
store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize);
@@ -1007,10 +1152,10 @@ static __kprobes void kprobe_perf_func(struct kprobe *kp,
}
/* Kretprobe profile handler */
-static __kprobes void kretprobe_perf_func(struct kretprobe_instance *ri,
- struct pt_regs *regs)
+static __kprobes void
+kretprobe_perf_func(struct trace_probe *tp, struct kretprobe_instance *ri,
+ struct pt_regs *regs)
{
- struct trace_probe *tp = container_of(ri->rp, struct trace_probe, rp);
struct ftrace_event_call *call = &tp->call;
struct kretprobe_trace_entry_head *entry;
struct hlist_head *head;
@@ -1044,20 +1189,19 @@ int kprobe_register(struct ftrace_event_call *event,
enum trace_reg type, void *data)
{
struct trace_probe *tp = (struct trace_probe *)event->data;
+ struct ftrace_event_file *file = data;
switch (type) {
case TRACE_REG_REGISTER:
- return enable_trace_probe(tp, TP_FLAG_TRACE);
+ return enable_trace_probe(tp, file);
case TRACE_REG_UNREGISTER:
- disable_trace_probe(tp, TP_FLAG_TRACE);
- return 0;
+ return disable_trace_probe(tp, file);
#ifdef CONFIG_PERF_EVENTS
case TRACE_REG_PERF_REGISTER:
- return enable_trace_probe(tp, TP_FLAG_PROFILE);
+ return enable_trace_probe(tp, NULL);
case TRACE_REG_PERF_UNREGISTER:
- disable_trace_probe(tp, TP_FLAG_PROFILE);
- return 0;
+ return disable_trace_probe(tp, NULL);
case TRACE_REG_PERF_OPEN:
case TRACE_REG_PERF_CLOSE:
case TRACE_REG_PERF_ADD:
@@ -1073,11 +1217,13 @@ int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs)
{
struct trace_probe *tp = container_of(kp, struct trace_probe, rp.kp);
+ tp->nhit++;
+
if (tp->flags & TP_FLAG_TRACE)
- kprobe_trace_func(kp, regs);
+ kprobe_trace_func(tp, regs);
#ifdef CONFIG_PERF_EVENTS
if (tp->flags & TP_FLAG_PROFILE)
- kprobe_perf_func(kp, regs);
+ kprobe_perf_func(tp, regs);
#endif
return 0; /* We don't tweek kernel, so just return 0 */
}
@@ -1087,11 +1233,13 @@ int kretprobe_dispatcher(struct kretprobe_instance *ri, struct pt_regs *regs)
{
struct trace_probe *tp = container_of(ri->rp, struct trace_probe, rp);
+ tp->nhit++;
+
if (tp->flags & TP_FLAG_TRACE)
- kretprobe_trace_func(ri, regs);
+ kretprobe_trace_func(tp, ri, regs);
#ifdef CONFIG_PERF_EVENTS
if (tp->flags & TP_FLAG_PROFILE)
- kretprobe_perf_func(ri, regs);
+ kretprobe_perf_func(tp, ri, regs);
#endif
return 0; /* We don't tweek kernel, so just return 0 */
}
@@ -1189,11 +1337,24 @@ static __used int kprobe_trace_selftest_target(int a1, int a2, int a3,
return a1 + a2 + a3 + a4 + a5 + a6;
}
+static struct ftrace_event_file *
+find_trace_probe_file(struct trace_probe *tp, struct trace_array *tr)
+{
+ struct ftrace_event_file *file;
+
+ list_for_each_entry(file, &tr->events, list)
+ if (file->event_call == &tp->call)
+ return file;
+
+ return NULL;
+}
+
static __init int kprobe_trace_self_tests_init(void)
{
int ret, warn = 0;
int (*target)(int, int, int, int, int, int);
struct trace_probe *tp;
+ struct ftrace_event_file *file;
target = kprobe_trace_selftest_target;
@@ -1203,31 +1364,43 @@ static __init int kprobe_trace_self_tests_init(void)
"$stack $stack0 +0($stack)",
create_trace_probe);
if (WARN_ON_ONCE(ret)) {
- pr_warning("error on probing function entry.\n");
+ pr_warn("error on probing function entry.\n");
warn++;
} else {
/* Enable trace point */
tp = find_trace_probe("testprobe", KPROBE_EVENT_SYSTEM);
if (WARN_ON_ONCE(tp == NULL)) {
- pr_warning("error on getting new probe.\n");
+ pr_warn("error on getting new probe.\n");
warn++;
- } else
- enable_trace_probe(tp, TP_FLAG_TRACE);
+ } else {
+ file = find_trace_probe_file(tp, top_trace_array());
+ if (WARN_ON_ONCE(file == NULL)) {
+ pr_warn("error on getting probe file.\n");
+ warn++;
+ } else
+ enable_trace_probe(tp, file);
+ }
}
ret = traceprobe_command("r:testprobe2 kprobe_trace_selftest_target "
"$retval", create_trace_probe);
if (WARN_ON_ONCE(ret)) {
- pr_warning("error on probing function return.\n");
+ pr_warn("error on probing function return.\n");
warn++;
} else {
/* Enable trace point */
tp = find_trace_probe("testprobe2", KPROBE_EVENT_SYSTEM);
if (WARN_ON_ONCE(tp == NULL)) {
- pr_warning("error on getting new probe.\n");
+ pr_warn("error on getting 2nd new probe.\n");
warn++;
- } else
- enable_trace_probe(tp, TP_FLAG_TRACE);
+ } else {
+ file = find_trace_probe_file(tp, top_trace_array());
+ if (WARN_ON_ONCE(file == NULL)) {
+ pr_warn("error on getting probe file.\n");
+ warn++;
+ } else
+ enable_trace_probe(tp, file);
+ }
}
if (warn)
@@ -1238,27 +1411,39 @@ static __init int kprobe_trace_self_tests_init(void)
/* Disable trace points before removing it */
tp = find_trace_probe("testprobe", KPROBE_EVENT_SYSTEM);
if (WARN_ON_ONCE(tp == NULL)) {
- pr_warning("error on getting test probe.\n");
+ pr_warn("error on getting test probe.\n");
warn++;
- } else
- disable_trace_probe(tp, TP_FLAG_TRACE);
+ } else {
+ file = find_trace_probe_file(tp, top_trace_array());
+ if (WARN_ON_ONCE(file == NULL)) {
+ pr_warn("error on getting probe file.\n");
+ warn++;
+ } else
+ disable_trace_probe(tp, file);
+ }
tp = find_trace_probe("testprobe2", KPROBE_EVENT_SYSTEM);
if (WARN_ON_ONCE(tp == NULL)) {
- pr_warning("error on getting 2nd test probe.\n");
+ pr_warn("error on getting 2nd test probe.\n");
warn++;
- } else
- disable_trace_probe(tp, TP_FLAG_TRACE);
+ } else {
+ file = find_trace_probe_file(tp, top_trace_array());
+ if (WARN_ON_ONCE(file == NULL)) {
+ pr_warn("error on getting probe file.\n");
+ warn++;
+ } else
+ disable_trace_probe(tp, file);
+ }
ret = traceprobe_command("-:testprobe", create_trace_probe);
if (WARN_ON_ONCE(ret)) {
- pr_warning("error on deleting a probe.\n");
+ pr_warn("error on deleting a probe.\n");
warn++;
}
ret = traceprobe_command("-:testprobe2", create_trace_probe);
if (WARN_ON_ONCE(ret)) {
- pr_warning("error on deleting a probe.\n");
+ pr_warn("error on deleting a probe.\n");
warn++;
}
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