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-rw-r--r--kernel/trace/Kconfig9
-rw-r--r--kernel/trace/ftrace.c19
-rw-r--r--kernel/trace/ftrace_internal.h8
-rw-r--r--kernel/trace/ring_buffer_benchmark.c2
-rw-r--r--kernel/trace/trace.c30
-rw-r--r--kernel/trace/trace_events.c6
-rw-r--r--kernel/trace/trace_functions_graph.c17
-rw-r--r--kernel/trace/trace_probe.c3
-rw-r--r--kernel/trace/trace_sched_wakeup.c3
9 files changed, 57 insertions, 40 deletions
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index 98da8998c25c..e08527f50d2a 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -146,7 +146,7 @@ config FUNCTION_TRACER
select GENERIC_TRACER
select CONTEXT_SWITCH_TRACER
select GLOB
- select TASKS_RCU if PREEMPT
+ select TASKS_RCU if PREEMPTION
help
Enable the kernel to trace every kernel function. This is done
by using a compiler feature to insert a small, 5-byte No-Operation
@@ -179,7 +179,7 @@ config TRACE_PREEMPT_TOGGLE
config PREEMPTIRQ_EVENTS
bool "Enable trace events for preempt and irq disable/enable"
select TRACE_IRQFLAGS
- select TRACE_PREEMPT_TOGGLE if PREEMPT
+ select TRACE_PREEMPT_TOGGLE if PREEMPTION
select GENERIC_TRACER
default n
help
@@ -214,7 +214,7 @@ config PREEMPT_TRACER
bool "Preemption-off Latency Tracer"
default n
depends on !ARCH_USES_GETTIMEOFFSET
- depends on PREEMPT
+ depends on PREEMPTION
select GENERIC_TRACER
select TRACER_MAX_TRACE
select RING_BUFFER_ALLOW_SWAP
@@ -520,7 +520,8 @@ config BPF_EVENTS
bool
default y
help
- This allows the user to attach BPF programs to kprobe events.
+ This allows the user to attach BPF programs to kprobe, uprobe, and
+ tracepoint events.
config DYNAMIC_EVENTS
def_bool n
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index eca34503f178..356b848c697a 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -2814,7 +2814,7 @@ int ftrace_shutdown(struct ftrace_ops *ops, int command)
* synchornize_rcu_tasks() will wait for those tasks to
* execute and either schedule voluntarily or enter user space.
*/
- if (IS_ENABLED(CONFIG_PREEMPT))
+ if (IS_ENABLED(CONFIG_PREEMPTION))
synchronize_rcu_tasks();
free_ops:
@@ -3095,6 +3095,14 @@ t_probe_next(struct seq_file *m, loff_t *pos)
hnd = &iter->probe_entry->hlist;
hash = iter->probe->ops.func_hash->filter_hash;
+
+ /*
+ * A probe being registered may temporarily have an empty hash
+ * and it's at the end of the func_probes list.
+ */
+ if (!hash || hash == EMPTY_HASH)
+ return NULL;
+
size = 1 << hash->size_bits;
retry:
@@ -4320,12 +4328,21 @@ register_ftrace_function_probe(char *glob, struct trace_array *tr,
mutex_unlock(&ftrace_lock);
+ /*
+ * Note, there's a small window here that the func_hash->filter_hash
+ * may be NULL or empty. Need to be carefule when reading the loop.
+ */
mutex_lock(&probe->ops.func_hash->regex_lock);
orig_hash = &probe->ops.func_hash->filter_hash;
old_hash = *orig_hash;
hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, old_hash);
+ if (!hash) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
ret = ftrace_match_records(hash, glob, strlen(glob));
/* Nothing found? */
diff --git a/kernel/trace/ftrace_internal.h b/kernel/trace/ftrace_internal.h
index 0515a2096f90..0456e0a3dab1 100644
--- a/kernel/trace/ftrace_internal.h
+++ b/kernel/trace/ftrace_internal.h
@@ -6,22 +6,22 @@
/*
* Traverse the ftrace_global_list, invoking all entries. The reason that we
- * can use rcu_dereference_raw_notrace() is that elements removed from this list
+ * can use rcu_dereference_raw_check() 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_notrace() calls are needed to handle
+ * mechanism. The rcu_dereference_raw_check() calls are needed to handle
* concurrent insertions into the ftrace_global_list.
*
* Silly Alpha and silly pointer-speculation compiler optimizations!
*/
#define do_for_each_ftrace_op(op, list) \
- op = rcu_dereference_raw_notrace(list); \
+ op = rcu_dereference_raw_check(list); \
do
/*
* Optimized for just a single item in the list (as that is the normal case).
*/
#define while_for_each_ftrace_op(op) \
- while (likely(op = rcu_dereference_raw_notrace((op)->next)) && \
+ while (likely(op = rcu_dereference_raw_check((op)->next)) && \
unlikely((op) != &ftrace_list_end))
extern struct ftrace_ops __rcu *ftrace_ops_list;
diff --git a/kernel/trace/ring_buffer_benchmark.c b/kernel/trace/ring_buffer_benchmark.c
index 0564f6db0561..09b0b49f346e 100644
--- a/kernel/trace/ring_buffer_benchmark.c
+++ b/kernel/trace/ring_buffer_benchmark.c
@@ -267,7 +267,7 @@ static void ring_buffer_producer(void)
if (consumer && !(cnt % wakeup_interval))
wake_up_process(consumer);
-#ifndef CONFIG_PREEMPT
+#ifndef CONFIG_PREEMPTION
/*
* If we are a non preempt kernel, the 10 second run will
* stop everything while it runs. Instead, we will call
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 525a97fbbc60..947ba433865f 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -1567,9 +1567,9 @@ update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu,
/**
* update_max_tr_single - only copy one trace over, and reset the rest
- * @tr - tracer
- * @tsk - task with the latency
- * @cpu - the cpu of the buffer to copy.
+ * @tr: tracer
+ * @tsk: task with the latency
+ * @cpu: the cpu of the buffer to copy.
*
* Flip the trace of a single CPU buffer between the @tr and the max_tr.
*/
@@ -1767,7 +1767,7 @@ static void __init apply_trace_boot_options(void);
/**
* register_tracer - register a tracer with the ftrace system.
- * @type - the plugin for the tracer
+ * @type: the plugin for the tracer
*
* Register a new plugin tracer.
*/
@@ -2230,9 +2230,9 @@ static bool tracing_record_taskinfo_skip(int flags)
/**
* tracing_record_taskinfo - record the task info of a task
*
- * @task - task to record
- * @flags - TRACE_RECORD_CMDLINE for recording comm
- * - TRACE_RECORD_TGID for recording tgid
+ * @task: task to record
+ * @flags: TRACE_RECORD_CMDLINE for recording comm
+ * TRACE_RECORD_TGID for recording tgid
*/
void tracing_record_taskinfo(struct task_struct *task, int flags)
{
@@ -2258,10 +2258,10 @@ void tracing_record_taskinfo(struct task_struct *task, int flags)
/**
* tracing_record_taskinfo_sched_switch - record task info for sched_switch
*
- * @prev - previous task during sched_switch
- * @next - next task during sched_switch
- * @flags - TRACE_RECORD_CMDLINE for recording comm
- * TRACE_RECORD_TGID for recording tgid
+ * @prev: previous task during sched_switch
+ * @next: next task during sched_switch
+ * @flags: TRACE_RECORD_CMDLINE for recording comm
+ * TRACE_RECORD_TGID for recording tgid
*/
void tracing_record_taskinfo_sched_switch(struct task_struct *prev,
struct task_struct *next, int flags)
@@ -2642,10 +2642,10 @@ static void ftrace_exports(struct ring_buffer_event *event)
preempt_disable_notrace();
- export = rcu_dereference_raw_notrace(ftrace_exports_list);
+ export = rcu_dereference_raw_check(ftrace_exports_list);
while (export) {
trace_process_export(export, event);
- export = rcu_dereference_raw_notrace(export->next);
+ export = rcu_dereference_raw_check(export->next);
}
preempt_enable_notrace();
@@ -3072,7 +3072,9 @@ static void trace_printk_start_stop_comm(int enabled)
/**
* trace_vbprintk - write binary msg to tracing buffer
- *
+ * @ip: The address of the caller
+ * @fmt: The string format to write to the buffer
+ * @args: Arguments for @fmt
*/
int trace_vbprintk(unsigned long ip, const char *fmt, va_list args)
{
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index c7506bc81b75..b89cdfe20bc1 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -255,12 +255,12 @@ void *trace_event_buffer_reserve(struct trace_event_buffer *fbuffer,
local_save_flags(fbuffer->flags);
fbuffer->pc = preempt_count();
/*
- * If CONFIG_PREEMPT is enabled, then the tracepoint itself disables
+ * If CONFIG_PREEMPTION is enabled, then the tracepoint itself disables
* preemption (adding one to the preempt_count). Since we are
* interested in the preempt_count at the time the tracepoint was
* hit, we need to subtract one to offset the increment.
*/
- if (IS_ENABLED(CONFIG_PREEMPT))
+ if (IS_ENABLED(CONFIG_PREEMPTION))
fbuffer->pc--;
fbuffer->trace_file = trace_file;
@@ -787,7 +787,7 @@ static int __ftrace_set_clr_event(struct trace_array *tr, const char *match,
return ret;
}
-static int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set)
+int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set)
{
char *event = NULL, *sub = NULL, *match;
int ret;
diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
index 69ebf3c2f1b5..78af97163147 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -137,6 +137,13 @@ int trace_graph_entry(struct ftrace_graph_ent *trace)
if (trace_recursion_test(TRACE_GRAPH_NOTRACE_BIT))
return 0;
+ /*
+ * Do not trace a function if it's filtered by set_graph_notrace.
+ * Make the index of ret stack negative to indicate that it should
+ * ignore further functions. But it needs its own ret stack entry
+ * to recover the original index in order to continue tracing after
+ * returning from the function.
+ */
if (ftrace_graph_notrace_addr(trace->func)) {
trace_recursion_set(TRACE_GRAPH_NOTRACE_BIT);
/*
@@ -156,16 +163,6 @@ int trace_graph_entry(struct ftrace_graph_ent *trace)
return 0;
/*
- * Do not trace a function if it's filtered by set_graph_notrace.
- * Make the index of ret stack negative to indicate that it should
- * ignore further functions. But it needs its own ret stack entry
- * to recover the original index in order to continue tracing after
- * returning from the function.
- */
- if (ftrace_graph_notrace_addr(trace->func))
- return 1;
-
- /*
* Stop here if tracing_threshold is set. We only write function return
* events to the ring buffer.
*/
diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index dbef0d135075..fb6bfbc5bf86 100644
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c
@@ -895,7 +895,8 @@ void trace_probe_cleanup(struct trace_probe *tp)
for (i = 0; i < tp->nr_args; i++)
traceprobe_free_probe_arg(&tp->args[i]);
- kfree(call->class->system);
+ if (call->class)
+ kfree(call->class->system);
kfree(call->name);
kfree(call->print_fmt);
}
diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c
index 743b2b520d34..5e43b9664eca 100644
--- a/kernel/trace/trace_sched_wakeup.c
+++ b/kernel/trace/trace_sched_wakeup.c
@@ -579,8 +579,7 @@ probe_wakeup(void *ignore, struct task_struct *p)
else
tracing_dl = 0;
- wakeup_task = p;
- get_task_struct(wakeup_task);
+ wakeup_task = get_task_struct(p);
local_save_flags(flags);
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