Merge tag 'trace-v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:

 - Added option for per CPU threads to the hwlat tracer

 - Have hwlat tracer handle hotplug CPUs

 - New tracer: osnoise, that detects latency caused by interrupts,
   softirqs and scheduling of other tasks.

 - Added timerlat tracer that creates a thread and measures in detail
   what sources of latency it has for wake ups.

 - Removed the "success" field of the sched_wakeup trace event. This has
   been hardcoded as "1" since 2015, no tooling should be looking at it
   now. If one exists, we can revert this commit, fix that tool and try
   to remove it again in the future.

 - tgid mapping fixed to handle more than PID_MAX_DEFAULT pids/tgids.

 - New boot command line option "tp_printk_stop", as tp_printk causes
   trace events to write to console. When user space starts, this can
   easily live lock the system. Having a boot option to stop just after
   boot up is useful to prevent that from happening.

 - Have ftrace_dump_on_oops boot command line option take numbers that
   match the numbers shown in /proc/sys/kernel/ftrace_dump_on_oops.

 - Bootconfig clean ups, fixes and enhancements.

 - New ktest script that tests bootconfig options.

 - Add tracepoint_probe_register_may_exist() to register a tracepoint
   without triggering a WARN*() if it already exists. BPF has a path
   from user space that can do this. All other paths are considered a
   bug.

 - Small clean ups and fixes

* tag 'trace-v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (49 commits)
  tracing: Resize tgid_map to pid_max, not PID_MAX_DEFAULT
  tracing: Simplify & fix saved_tgids logic
  treewide: Add missing semicolons to __assign_str uses
  tracing: Change variable type as bool for clean-up
  trace/timerlat: Fix indentation on timerlat_main()
  trace/osnoise: Make 'noise' variable s64 in run_osnoise()
  tracepoint: Add tracepoint_probe_register_may_exist() for BPF tracing
  tracing: Fix spelling in osnoise tracer "interferences" -> "interference"
  Documentation: Fix a typo on trace/osnoise-tracer
  trace/osnoise: Fix return value on osnoise_init_hotplug_support
  trace/osnoise: Make interval u64 on osnoise_main
  trace/osnoise: Fix 'no previous prototype' warnings
  tracing: Have osnoise_main() add a quiescent state for task rcu
  seq_buf: Make trace_seq_putmem_hex() support data longer than 8
  seq_buf: Fix overflow in seq_buf_putmem_hex()
  trace/osnoise: Support hotplug operations
  trace/hwlat: Support hotplug operations
  trace/hwlat: Protect kdata->kthread with get/put_online_cpus
  trace: Add timerlat tracer
  trace: Add osnoise tracer
  ...

1 files changed, 29 insertions, 6 deletions

diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index d5d8c088a55d..a180abf76d4e 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -45,6 +45,8 @@ enum trace_type {
 	TRACE_BLK,
 	TRACE_BPUTS,
 	TRACE_HWLAT,
+	TRACE_OSNOISE,
+	TRACE_TIMERLAT,
 	TRACE_RAW_DATA,
 	TRACE_FUNC_REPEATS,
 
@@ -290,7 +292,8 @@ struct trace_array {
 	struct array_buffer	max_buffer;
 	bool			allocated_snapshot;
 #endif
-#if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER)
+#if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER) \
+	|| defined(CONFIG_OSNOISE_TRACER)
 	unsigned long		max_latency;
 #ifdef CONFIG_FSNOTIFY
 	struct dentry		*d_max_latency;
@@ -438,6 +441,8 @@ extern void __ftrace_bad_type(void);
 		IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT);	\
 		IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS);	\
 		IF_ASSIGN(var, ent, struct hwlat_entry, TRACE_HWLAT);	\
+		IF_ASSIGN(var, ent, struct osnoise_entry, TRACE_OSNOISE);\
+		IF_ASSIGN(var, ent, struct timerlat_entry, TRACE_TIMERLAT);\
 		IF_ASSIGN(var, ent, struct raw_data_entry, TRACE_RAW_DATA);\
 		IF_ASSIGN(var, ent, struct trace_mmiotrace_rw,		\
 			  TRACE_MMIO_RW);				\
@@ -668,15 +673,15 @@ void update_max_tr_single(struct trace_array *tr,
 			  struct task_struct *tsk, int cpu);
 #endif /* CONFIG_TRACER_MAX_TRACE */
 
-#if (defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER)) && \
-	defined(CONFIG_FSNOTIFY)
+#if (defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER) \
+	|| defined(CONFIG_OSNOISE_TRACER)) && defined(CONFIG_FSNOTIFY)
+#define LATENCY_FS_NOTIFY
+#endif
 
+#ifdef LATENCY_FS_NOTIFY
 void latency_fsnotify(struct trace_array *tr);
-
 #else
-
 static inline void latency_fsnotify(struct trace_array *tr) { }
-
 #endif
 
 #ifdef CONFIG_STACKTRACE
@@ -1945,4 +1950,22 @@ static inline bool is_good_name(const char *name)
 	return true;
 }
 
+/*
+ * This is a generic way to read and write a u64 value from a file in tracefs.
+ *
+ * The value is stored on the variable pointed by *val. The value needs
+ * to be at least *min and at most *max. The write is protected by an
+ * existing *lock.
+ */
+struct trace_min_max_param {
+	struct mutex	*lock;
+	u64		*val;
+	u64		*min;
+	u64		*max;
+};
+
+#define U64_STR_SIZE		24	/* 20 digits max */
+
+extern const struct file_operations trace_min_max_fops;
+
 #endif /* _LINUX_KERNEL_TRACE_H */