[GIT PULL] tracing: Updates for 4.14
From: Steven Rostedt
Date: Fri Sep 08 2017 - 10:09:25 EST
Linus,
Nothing new in development for this release. These are mostly
fixes that were found during development of changes for the next merge
window and fixes that were sent to me late in the last cycle.
Please pull the latest trace-v4.14 tree, which can be found at:
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace.git
trace-v4.14
Tag SHA1: b980ff9ed13dcb0cb71c49950e654778de6dba82
Head SHA1: 170b3b1050e28d1ba0700e262f0899ffa4fccc52
Baohong Liu (1):
tracing: Apply trace_clock changes to instance max buffer
Chunyu Hu (1):
tracing: Fix clear of RECORDED_TGID flag when disabling trace event
Steven Rostedt (VMware) (5):
tracing: Only have rmmod clear buffers that its events were active in
ftrace: Zero out ftrace hashes when a module is removed
ftrace: Fix selftest goto location on error
ftrace: Fix memleak when unregistering dynamic ops when tracing disabled
tracing: Add barrier to trace_printk() buffer nesting modification
Zev Weiss (1):
ftrace: Fix debug preempt config name in stack_tracer_{en,dis}able
----
include/linux/ftrace.h | 4 +--
include/linux/trace_events.h | 8 ++---
kernel/trace/ftrace.c | 68 ++++++++++++++++++++++++++++++++++++++-----
kernel/trace/trace.c | 13 +++++++--
kernel/trace/trace.h | 1 +
kernel/trace/trace_events.c | 17 +++++------
kernel/trace/trace_selftest.c | 2 +-
7 files changed, 87 insertions(+), 26 deletions(-)
---------------------------
diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h
index 6383115e9d2c..2e028854bac7 100644
--- a/include/linux/ftrace.h
+++ b/include/linux/ftrace.h
@@ -307,7 +307,7 @@ DECLARE_PER_CPU(int, disable_stack_tracer);
static inline void stack_tracer_disable(void)
{
/* Preemption or interupts must be disabled */
- if (IS_ENABLED(CONFIG_PREEMPT_DEBUG))
+ if (IS_ENABLED(CONFIG_DEBUG_PREEMPT))
WARN_ON_ONCE(!preempt_count() || !irqs_disabled());
this_cpu_inc(disable_stack_tracer);
}
@@ -320,7 +320,7 @@ static inline void stack_tracer_disable(void)
*/
static inline void stack_tracer_enable(void)
{
- if (IS_ENABLED(CONFIG_PREEMPT_DEBUG))
+ if (IS_ENABLED(CONFIG_DEBUG_PREEMPT))
WARN_ON_ONCE(!preempt_count() || !irqs_disabled());
this_cpu_dec(disable_stack_tracer);
}
diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h
index 536c80ff7ad9..3702b9cb5dc8 100644
--- a/include/linux/trace_events.h
+++ b/include/linux/trace_events.h
@@ -217,7 +217,6 @@ enum {
TRACE_EVENT_FL_CAP_ANY_BIT,
TRACE_EVENT_FL_NO_SET_FILTER_BIT,
TRACE_EVENT_FL_IGNORE_ENABLE_BIT,
- TRACE_EVENT_FL_WAS_ENABLED_BIT,
TRACE_EVENT_FL_TRACEPOINT_BIT,
TRACE_EVENT_FL_KPROBE_BIT,
TRACE_EVENT_FL_UPROBE_BIT,
@@ -229,9 +228,6 @@ enum {
* CAP_ANY - Any user can enable for perf
* NO_SET_FILTER - Set when filter has error and is to be ignored
* IGNORE_ENABLE - For trace internal events, do not enable with debugfs file
- * WAS_ENABLED - Set and stays set when an event was ever enabled
- * (used for module unloading, if a module event is enabled,
- * it is best to clear the buffers that used it).
* TRACEPOINT - Event is a tracepoint
* KPROBE - Event is a kprobe
* UPROBE - Event is a uprobe
@@ -241,7 +237,6 @@ enum {
TRACE_EVENT_FL_CAP_ANY = (1 << TRACE_EVENT_FL_CAP_ANY_BIT),
TRACE_EVENT_FL_NO_SET_FILTER = (1 << TRACE_EVENT_FL_NO_SET_FILTER_BIT),
TRACE_EVENT_FL_IGNORE_ENABLE = (1 << TRACE_EVENT_FL_IGNORE_ENABLE_BIT),
- TRACE_EVENT_FL_WAS_ENABLED = (1 << TRACE_EVENT_FL_WAS_ENABLED_BIT),
TRACE_EVENT_FL_TRACEPOINT = (1 << TRACE_EVENT_FL_TRACEPOINT_BIT),
TRACE_EVENT_FL_KPROBE = (1 << TRACE_EVENT_FL_KPROBE_BIT),
TRACE_EVENT_FL_UPROBE = (1 << TRACE_EVENT_FL_UPROBE_BIT),
@@ -306,6 +301,7 @@ enum {
EVENT_FILE_FL_TRIGGER_MODE_BIT,
EVENT_FILE_FL_TRIGGER_COND_BIT,
EVENT_FILE_FL_PID_FILTER_BIT,
+ EVENT_FILE_FL_WAS_ENABLED_BIT,
};
/*
@@ -321,6 +317,7 @@ enum {
* TRIGGER_MODE - When set, invoke the triggers associated with the event
* TRIGGER_COND - When set, one or more triggers has an associated filter
* PID_FILTER - When set, the event is filtered based on pid
+ * WAS_ENABLED - Set when enabled to know to clear trace on module removal
*/
enum {
EVENT_FILE_FL_ENABLED = (1 << EVENT_FILE_FL_ENABLED_BIT),
@@ -333,6 +330,7 @@ enum {
EVENT_FILE_FL_TRIGGER_MODE = (1 << EVENT_FILE_FL_TRIGGER_MODE_BIT),
EVENT_FILE_FL_TRIGGER_COND = (1 << EVENT_FILE_FL_TRIGGER_COND_BIT),
EVENT_FILE_FL_PID_FILTER = (1 << EVENT_FILE_FL_PID_FILTER_BIT),
+ EVENT_FILE_FL_WAS_ENABLED = (1 << EVENT_FILE_FL_WAS_ENABLED_BIT),
};
struct trace_event_file {
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 96cea88fa00f..6abfafd7f173 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -2828,13 +2828,14 @@ static int ftrace_shutdown(struct ftrace_ops *ops, int command)
if (!command || !ftrace_enabled) {
/*
- * If these are per_cpu ops, they still need their
- * per_cpu field freed. Since, function tracing is
+ * If these are dynamic or per_cpu ops, they still
+ * need their data freed. Since, function tracing is
* not currently active, we can just free them
* without synchronizing all CPUs.
*/
- if (ops->flags & FTRACE_OPS_FL_PER_CPU)
- per_cpu_ops_free(ops);
+ if (ops->flags & (FTRACE_OPS_FL_DYNAMIC | FTRACE_OPS_FL_PER_CPU))
+ goto free_ops;
+
return 0;
}
@@ -2900,6 +2901,7 @@ static int ftrace_shutdown(struct ftrace_ops *ops, int command)
if (IS_ENABLED(CONFIG_PREEMPT))
synchronize_rcu_tasks();
+ free_ops:
arch_ftrace_trampoline_free(ops);
if (ops->flags & FTRACE_OPS_FL_PER_CPU)
@@ -5690,10 +5692,51 @@ static int referenced_filters(struct dyn_ftrace *rec)
return cnt;
}
+static void
+clear_mod_from_hash(struct ftrace_page *pg, struct ftrace_hash *hash)
+{
+ struct ftrace_func_entry *entry;
+ struct dyn_ftrace *rec;
+ int i;
+
+ if (ftrace_hash_empty(hash))
+ return;
+
+ for (i = 0; i < pg->index; i++) {
+ rec = &pg->records[i];
+ entry = __ftrace_lookup_ip(hash, rec->ip);
+ /*
+ * Do not allow this rec to match again.
+ * Yeah, it may waste some memory, but will be removed
+ * if/when the hash is modified again.
+ */
+ if (entry)
+ entry->ip = 0;
+ }
+}
+
+/* Clear any records from hashs */
+static void clear_mod_from_hashes(struct ftrace_page *pg)
+{
+ struct trace_array *tr;
+
+ mutex_lock(&trace_types_lock);
+ list_for_each_entry(tr, &ftrace_trace_arrays, list) {
+ if (!tr->ops || !tr->ops->func_hash)
+ continue;
+ mutex_lock(&tr->ops->func_hash->regex_lock);
+ clear_mod_from_hash(pg, tr->ops->func_hash->filter_hash);
+ clear_mod_from_hash(pg, tr->ops->func_hash->notrace_hash);
+ mutex_unlock(&tr->ops->func_hash->regex_lock);
+ }
+ mutex_unlock(&trace_types_lock);
+}
+
void ftrace_release_mod(struct module *mod)
{
struct dyn_ftrace *rec;
struct ftrace_page **last_pg;
+ struct ftrace_page *tmp_page = NULL;
struct ftrace_page *pg;
int order;
@@ -5723,14 +5766,25 @@ void ftrace_release_mod(struct module *mod)
ftrace_update_tot_cnt -= pg->index;
*last_pg = pg->next;
- order = get_count_order(pg->size / ENTRIES_PER_PAGE);
- free_pages((unsigned long)pg->records, order);
- kfree(pg);
+
+ pg->next = tmp_page;
+ tmp_page = pg;
} else
last_pg = &pg->next;
}
out_unlock:
mutex_unlock(&ftrace_lock);
+
+ for (pg = tmp_page; pg; pg = tmp_page) {
+
+ /* Needs to be called outside of ftrace_lock */
+ clear_mod_from_hashes(pg);
+
+ order = get_count_order(pg->size / ENTRIES_PER_PAGE);
+ free_pages((unsigned long)pg->records, order);
+ tmp_page = pg->next;
+ kfree(pg);
+ }
}
void ftrace_module_enable(struct module *mod)
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 44004d8aa3b3..5360b7aec57a 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -1702,6 +1702,9 @@ void tracing_reset_all_online_cpus(void)
struct trace_array *tr;
list_for_each_entry(tr, &ftrace_trace_arrays, list) {
+ if (!tr->clear_trace)
+ continue;
+ tr->clear_trace = false;
tracing_reset_online_cpus(&tr->trace_buffer);
#ifdef CONFIG_TRACER_MAX_TRACE
tracing_reset_online_cpus(&tr->max_buffer);
@@ -2799,11 +2802,17 @@ static char *get_trace_buf(void)
if (!buffer || buffer->nesting >= 4)
return NULL;
- return &buffer->buffer[buffer->nesting++][0];
+ buffer->nesting++;
+
+ /* Interrupts must see nesting incremented before we use the buffer */
+ barrier();
+ return &buffer->buffer[buffer->nesting][0];
}
static void put_trace_buf(void)
{
+ /* Don't let the decrement of nesting leak before this */
+ barrier();
this_cpu_dec(trace_percpu_buffer->nesting);
}
@@ -6220,7 +6229,7 @@ static int tracing_set_clock(struct trace_array *tr, const char *clockstr)
tracing_reset_online_cpus(&tr->trace_buffer);
#ifdef CONFIG_TRACER_MAX_TRACE
- if (tr->flags & TRACE_ARRAY_FL_GLOBAL && tr->max_buffer.buffer)
+ if (tr->max_buffer.buffer)
ring_buffer_set_clock(tr->max_buffer.buffer, trace_clocks[i].func);
tracing_reset_online_cpus(&tr->max_buffer);
#endif
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 490ba229931d..fb5d54d0d1b3 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -245,6 +245,7 @@ struct trace_array {
int stop_count;
int clock_id;
int nr_topts;
+ bool clear_trace;
struct tracer *current_trace;
unsigned int trace_flags;
unsigned char trace_flags_index[TRACE_FLAGS_MAX_SIZE];
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 36132f9280e6..87468398b9ed 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -406,7 +406,7 @@ static int __ftrace_event_enable_disable(struct trace_event_file *file,
if (file->flags & EVENT_FILE_FL_RECORDED_TGID) {
tracing_stop_tgid_record();
- clear_bit(EVENT_FILE_FL_RECORDED_CMD_BIT, &file->flags);
+ clear_bit(EVENT_FILE_FL_RECORDED_TGID_BIT, &file->flags);
}
call->class->reg(call, TRACE_REG_UNREGISTER, file);
@@ -466,7 +466,7 @@ static int __ftrace_event_enable_disable(struct trace_event_file *file,
set_bit(EVENT_FILE_FL_ENABLED_BIT, &file->flags);
/* WAS_ENABLED gets set but never cleared. */
- call->flags |= TRACE_EVENT_FL_WAS_ENABLED;
+ set_bit(EVENT_FILE_FL_WAS_ENABLED_BIT, &file->flags);
}
break;
}
@@ -2058,6 +2058,10 @@ static void event_remove(struct trace_event_call *call)
do_for_each_event_file(tr, file) {
if (file->event_call != call)
continue;
+
+ if (file->flags & EVENT_FILE_FL_WAS_ENABLED)
+ tr->clear_trace = true;
+
ftrace_event_enable_disable(file, 0);
/*
* The do_for_each_event_file() is
@@ -2396,15 +2400,11 @@ static void trace_module_add_events(struct module *mod)
static void trace_module_remove_events(struct module *mod)
{
struct trace_event_call *call, *p;
- bool clear_trace = false;
down_write(&trace_event_sem);
list_for_each_entry_safe(call, p, &ftrace_events, list) {
- if (call->mod == mod) {
- if (call->flags & TRACE_EVENT_FL_WAS_ENABLED)
- clear_trace = true;
+ if (call->mod == mod)
__trace_remove_event_call(call);
- }
}
up_write(&trace_event_sem);
@@ -2416,8 +2416,7 @@ static void trace_module_remove_events(struct module *mod)
* over from this module may be passed to the new module events and
* unexpected results may occur.
*/
- if (clear_trace)
- tracing_reset_all_online_cpus();
+ tracing_reset_all_online_cpus();
}
static int trace_module_notify(struct notifier_block *self,
diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c
index cb917cebae29..b17ec642793b 100644
--- a/kernel/trace/trace_selftest.c
+++ b/kernel/trace/trace_selftest.c
@@ -273,7 +273,7 @@ static int trace_selftest_ops(struct trace_array *tr, int cnt)
goto out_free;
if (cnt > 1) {
if (trace_selftest_test_global_cnt == 0)
- goto out;
+ goto out_free;
}
if (trace_selftest_test_dyn_cnt == 0)
goto out_free;