Merge tag 'trace-v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:

 - kprobes: Restructured stack unwinder to show properly on x86 when a
   stack dump happens from a kretprobe callback.

 - Fix to bootconfig parsing

 - Have tracefs allow owner and group permissions by default (only
   denying others). There's been pressure to allow non root to tracefs
   in a controlled fashion, and using groups is probably the safest.

 - Bootconfig memory managament updates.

 - Bootconfig clean up to have the tools directory be less dependent on
   changes in the kernel tree.

 - Allow perf to be traced by function tracer.

 - Rewrite of function graph tracer to be a callback from the function
   tracer instead of having its own trampoline (this change will happen
   on an arch by arch basis, and currently only x86_64 implements it).

 - Allow multiple direct trampolines (bpf hooks to functions) be batched
   together in one synchronization.

 - Allow histogram triggers to add variables that can perform
   calculations against the event's fields.

 - Use the linker to determine architecture callbacks from the ftrace
   trampoline to allow for proper parameter prototypes and prevent
   warnings from the compiler.

 - Extend histogram triggers to key off of variables.

 - Have trace recursion use bit magic to determine preempt context over
   if branches.

 - Have trace recursion disable preemption as all use cases do anyway.

 - Added testing for verification of tracing utilities.

 - Various small clean ups and fixes.

* tag 'trace-v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (101 commits)
  tracing/histogram: Fix semicolon.cocci warnings
  tracing/histogram: Fix documentation inline emphasis warning
  tracing: Increase PERF_MAX_TRACE_SIZE to handle Sentinel1 and docker together
  tracing: Show size of requested perf buffer
  bootconfig: Initialize ret in xbc_parse_tree()
  ftrace: do CPU checking after preemption disabled
  ftrace: disable preemption when recursion locked
  tracing/histogram: Document expression arithmetic and constants
  tracing/histogram: Optimize division by a power of 2
  tracing/histogram: Covert expr to const if both operands are constants
  tracing/histogram: Simplify handling of .sym-offset in expressions
  tracing: Fix operator precedence for hist triggers expression
  tracing: Add division and multiplication support for hist triggers
  tracing: Add support for creating hist trigger variables from literal
  selftests/ftrace: Stop tracing while reading the trace file by default
  MAINTAINERS: Update KPROBES and TRACING entries
  test_kprobes: Move it from kernel/ to lib/
  docs, kprobes: Remove invalid URL and add new reference
  samples/kretprobes: Fix return value if register_kretprobe() failed
  lib/bootconfig: Fix the xbc_get_info kerneldoc
  ...

1 files changed, 64 insertions, 87 deletions

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index bc677cd64224..c88bbfe75d1d 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -512,12 +512,6 @@ int call_filter_check_discard(struct trace_event_call *call, void *rec,
 	return 0;
 }
 
-void trace_free_pid_list(struct trace_pid_list *pid_list)
-{
-	vfree(pid_list->pids);
-	kfree(pid_list);
-}
-
 /**
  * trace_find_filtered_pid - check if a pid exists in a filtered_pid list
  * @filtered_pids: The list of pids to check
@@ -528,14 +522,7 @@ void trace_free_pid_list(struct trace_pid_list *pid_list)
 bool
 trace_find_filtered_pid(struct trace_pid_list *filtered_pids, pid_t search_pid)
 {
-	/*
-	 * If pid_max changed after filtered_pids was created, we
-	 * by default ignore all pids greater than the previous pid_max.
-	 */
-	if (search_pid >= filtered_pids->pid_max)
-		return false;
-
-	return test_bit(search_pid, filtered_pids->pids);
+	return trace_pid_list_is_set(filtered_pids, search_pid);
 }
 
 /**
@@ -592,15 +579,11 @@ void trace_filter_add_remove_task(struct trace_pid_list *pid_list,
 			return;
 	}
 
-	/* Sorry, but we don't support pid_max changing after setting */
-	if (task->pid >= pid_list->pid_max)
-		return;
-
 	/* "self" is set for forks, and NULL for exits */
 	if (self)
-		set_bit(task->pid, pid_list->pids);
+		trace_pid_list_set(pid_list, task->pid);
 	else
-		clear_bit(task->pid, pid_list->pids);
+		trace_pid_list_clear(pid_list, task->pid);
 }
 
 /**
@@ -617,18 +600,19 @@ void trace_filter_add_remove_task(struct trace_pid_list *pid_list,
  */
 void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos)
 {
-	unsigned long pid = (unsigned long)v;
+	long pid = (unsigned long)v;
+	unsigned int next;
 
 	(*pos)++;
 
 	/* pid already is +1 of the actual previous bit */
-	pid = find_next_bit(pid_list->pids, pid_list->pid_max, pid);
+	if (trace_pid_list_next(pid_list, pid, &next) < 0)
+		return NULL;
 
-	/* Return pid + 1 to allow zero to be represented */
-	if (pid < pid_list->pid_max)
-		return (void *)(pid + 1);
+	pid = next;
 
-	return NULL;
+	/* Return pid + 1 to allow zero to be represented */
+	return (void *)(pid + 1);
 }
 
 /**
@@ -645,12 +629,14 @@ void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos)
 void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos)
 {
 	unsigned long pid;
+	unsigned int first;
 	loff_t l = 0;
 
-	pid = find_first_bit(pid_list->pids, pid_list->pid_max);
-	if (pid >= pid_list->pid_max)
+	if (trace_pid_list_first(pid_list, &first) < 0)
 		return NULL;
 
+	pid = first;
+
 	/* Return pid + 1 so that zero can be the exit value */
 	for (pid++; pid && l < *pos;
 	     pid = (unsigned long)trace_pid_next(pid_list, (void *)pid, &l))
@@ -686,7 +672,7 @@ int trace_pid_write(struct trace_pid_list *filtered_pids,
 	unsigned long val;
 	int nr_pids = 0;
 	ssize_t read = 0;
-	ssize_t ret = 0;
+	ssize_t ret;
 	loff_t pos;
 	pid_t pid;
 
@@ -699,34 +685,23 @@ int trace_pid_write(struct trace_pid_list *filtered_pids,
 	 * the user. If the operation fails, then the current list is
 	 * not modified.
 	 */
-	pid_list = kmalloc(sizeof(*pid_list), GFP_KERNEL);
+	pid_list = trace_pid_list_alloc();
 	if (!pid_list) {
 		trace_parser_put(&parser);
 		return -ENOMEM;
 	}
 
-	pid_list->pid_max = READ_ONCE(pid_max);
-
-	/* Only truncating will shrink pid_max */
-	if (filtered_pids && filtered_pids->pid_max > pid_list->pid_max)
-		pid_list->pid_max = filtered_pids->pid_max;
-
-	pid_list->pids = vzalloc((pid_list->pid_max + 7) >> 3);
-	if (!pid_list->pids) {
-		trace_parser_put(&parser);
-		kfree(pid_list);
-		return -ENOMEM;
-	}
-
 	if (filtered_pids) {
 		/* copy the current bits to the new max */
-		for_each_set_bit(pid, filtered_pids->pids,
-				 filtered_pids->pid_max) {
-			set_bit(pid, pid_list->pids);
+		ret = trace_pid_list_first(filtered_pids, &pid);
+		while (!ret) {
+			trace_pid_list_set(pid_list, pid);
+			ret = trace_pid_list_next(filtered_pids, pid + 1, &pid);
 			nr_pids++;
 		}
 	}
 
+	ret = 0;
 	while (cnt > 0) {
 
 		pos = 0;
@@ -742,12 +717,13 @@ int trace_pid_write(struct trace_pid_list *filtered_pids,
 		ret = -EINVAL;
 		if (kstrtoul(parser.buffer, 0, &val))
 			break;
-		if (val >= pid_list->pid_max)
-			break;
 
 		pid = (pid_t)val;
 
-		set_bit(pid, pid_list->pids);
+		if (trace_pid_list_set(pid_list, pid) < 0) {
+			ret = -1;
+			break;
+		}
 		nr_pids++;
 
 		trace_parser_clear(&parser);
@@ -756,13 +732,13 @@ int trace_pid_write(struct trace_pid_list *filtered_pids,
 	trace_parser_put(&parser);
 
 	if (ret < 0) {
-		trace_free_pid_list(pid_list);
+		trace_pid_list_free(pid_list);
 		return ret;
 	}
 
 	if (!nr_pids) {
 		/* Cleared the list of pids */
-		trace_free_pid_list(pid_list);
+		trace_pid_list_free(pid_list);
 		read = ret;
 		pid_list = NULL;
 	}
@@ -1714,7 +1690,8 @@ static void trace_create_maxlat_file(struct trace_array *tr,
 {
 	INIT_WORK(&tr->fsnotify_work, latency_fsnotify_workfn);
 	init_irq_work(&tr->fsnotify_irqwork, latency_fsnotify_workfn_irq);
-	tr->d_max_latency = trace_create_file("tracing_max_latency", 0644,
+	tr->d_max_latency = trace_create_file("tracing_max_latency",
+					      TRACE_MODE_WRITE,
 					      d_tracer, &tr->max_latency,
 					      &tracing_max_lat_fops);
 }
@@ -1748,8 +1725,8 @@ void latency_fsnotify(struct trace_array *tr)
 	|| defined(CONFIG_OSNOISE_TRACER)
 
 #define trace_create_maxlat_file(tr, d_tracer)				\
-	trace_create_file("tracing_max_latency", 0644, d_tracer,	\
-			  &tr->max_latency, &tracing_max_lat_fops)
+	trace_create_file("tracing_max_latency", TRACE_MODE_WRITE,	\
+			  d_tracer, &tr->max_latency, &tracing_max_lat_fops)
 
 #else
 #define trace_create_maxlat_file(tr, d_tracer)	 do { } while (0)
@@ -6077,7 +6054,7 @@ trace_insert_eval_map_file(struct module *mod, struct trace_eval_map **start,
 
 static void trace_create_eval_file(struct dentry *d_tracer)
 {
-	trace_create_file("eval_map", 0444, d_tracer,
+	trace_create_file("eval_map", TRACE_MODE_READ, d_tracer,
 			  NULL, &tracing_eval_map_fops);
 }
 
@@ -8590,27 +8567,27 @@ tracing_init_tracefs_percpu(struct trace_array *tr, long cpu)
 	}
 
 	/* per cpu trace_pipe */
-	trace_create_cpu_file("trace_pipe", 0444, d_cpu,
+	trace_create_cpu_file("trace_pipe", TRACE_MODE_READ, d_cpu,
 				tr, cpu, &tracing_pipe_fops);
 
 	/* per cpu trace */
-	trace_create_cpu_file("trace", 0644, d_cpu,
+	trace_create_cpu_file("trace", TRACE_MODE_WRITE, d_cpu,
 				tr, cpu, &tracing_fops);
 
-	trace_create_cpu_file("trace_pipe_raw", 0444, d_cpu,
+	trace_create_cpu_file("trace_pipe_raw", TRACE_MODE_READ, d_cpu,
 				tr, cpu, &tracing_buffers_fops);
 
-	trace_create_cpu_file("stats", 0444, d_cpu,
+	trace_create_cpu_file("stats", TRACE_MODE_READ, d_cpu,
 				tr, cpu, &tracing_stats_fops);
 
-	trace_create_cpu_file("buffer_size_kb", 0444, d_cpu,
+	trace_create_cpu_file("buffer_size_kb", TRACE_MODE_READ, d_cpu,
 				tr, cpu, &tracing_entries_fops);
 
 #ifdef CONFIG_TRACER_SNAPSHOT
-	trace_create_cpu_file("snapshot", 0644, d_cpu,
+	trace_create_cpu_file("snapshot", TRACE_MODE_WRITE, d_cpu,
 				tr, cpu, &snapshot_fops);
 
-	trace_create_cpu_file("snapshot_raw", 0444, d_cpu,
+	trace_create_cpu_file("snapshot_raw", TRACE_MODE_READ, d_cpu,
 				tr, cpu, &snapshot_raw_fops);
 #endif
 }
@@ -8816,8 +8793,8 @@ create_trace_option_file(struct trace_array *tr,
 	topt->opt = opt;
 	topt->tr = tr;
 
-	topt->entry = trace_create_file(opt->name, 0644, t_options, topt,
-				    &trace_options_fops);
+	topt->entry = trace_create_file(opt->name, TRACE_MODE_WRITE,
+					t_options, topt, &trace_options_fops);
 
 }
 
@@ -8892,7 +8869,7 @@ create_trace_option_core_file(struct trace_array *tr,
 	if (!t_options)
 		return NULL;
 
-	return trace_create_file(option, 0644, t_options,
+	return trace_create_file(option, TRACE_MODE_WRITE, t_options,
 				 (void *)&tr->trace_flags_index[index],
 				 &trace_options_core_fops);
 }
@@ -9417,28 +9394,28 @@ init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer)
 	struct trace_event_file *file;
 	int cpu;
 
-	trace_create_file("available_tracers", 0444, d_tracer,
+	trace_create_file("available_tracers", TRACE_MODE_READ, d_tracer,
 			tr, &show_traces_fops);
 
-	trace_create_file("current_tracer", 0644, d_tracer,
+	trace_create_file("current_tracer", TRACE_MODE_WRITE, d_tracer,
 			tr, &set_tracer_fops);
 
-	trace_create_file("tracing_cpumask", 0644, d_tracer,
+	trace_create_file("tracing_cpumask", TRACE_MODE_WRITE, d_tracer,
 			  tr, &tracing_cpumask_fops);
 
-	trace_create_file("trace_options", 0644, d_tracer,
+	trace_create_file("trace_options", TRACE_MODE_WRITE, d_tracer,
 			  tr, &tracing_iter_fops);
 
-	trace_create_file("trace", 0644, d_tracer,
+	trace_create_file("trace", TRACE_MODE_WRITE, d_tracer,
 			  tr, &tracing_fops);
 
-	trace_create_file("trace_pipe", 0444, d_tracer,
+	trace_create_file("trace_pipe", TRACE_MODE_READ, d_tracer,
 			  tr, &tracing_pipe_fops);
 
-	trace_create_file("buffer_size_kb", 0644, d_tracer,
+	trace_create_file("buffer_size_kb", TRACE_MODE_WRITE, d_tracer,
 			  tr, &tracing_entries_fops);
 
-	trace_create_file("buffer_total_size_kb", 0444, d_tracer,
+	trace_create_file("buffer_total_size_kb", TRACE_MODE_READ, d_tracer,
 			  tr, &tracing_total_entries_fops);
 
 	trace_create_file("free_buffer", 0200, d_tracer,
@@ -9449,25 +9426,25 @@ init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer)
 
 	file = __find_event_file(tr, "ftrace", "print");
 	if (file && file->dir)
-		trace_create_file("trigger", 0644, file->dir, file,
-				  &event_trigger_fops);
+		trace_create_file("trigger", TRACE_MODE_WRITE, file->dir,
+				  file, &event_trigger_fops);
 	tr->trace_marker_file = file;
 
 	trace_create_file("trace_marker_raw", 0220, d_tracer,
 			  tr, &tracing_mark_raw_fops);
 
-	trace_create_file("trace_clock", 0644, d_tracer, tr,
+	trace_create_file("trace_clock", TRACE_MODE_WRITE, d_tracer, tr,
 			  &trace_clock_fops);
 
-	trace_create_file("tracing_on", 0644, d_tracer,
+	trace_create_file("tracing_on", TRACE_MODE_WRITE, d_tracer,
 			  tr, &rb_simple_fops);
 
-	trace_create_file("timestamp_mode", 0444, d_tracer, tr,
+	trace_create_file("timestamp_mode", TRACE_MODE_READ, d_tracer, tr,
 			  &trace_time_stamp_mode_fops);
 
 	tr->buffer_percent = 50;
 
-	trace_create_file("buffer_percent", 0444, d_tracer,
+	trace_create_file("buffer_percent", TRACE_MODE_READ, d_tracer,
 			tr, &buffer_percent_fops);
 
 	create_trace_options_dir(tr);
@@ -9478,11 +9455,11 @@ init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer)
 		MEM_FAIL(1, "Could not allocate function filter files");
 
 #ifdef CONFIG_TRACER_SNAPSHOT
-	trace_create_file("snapshot", 0644, d_tracer,
+	trace_create_file("snapshot", TRACE_MODE_WRITE, d_tracer,
 			  tr, &snapshot_fops);
 #endif
 
-	trace_create_file("error_log", 0644, d_tracer,
+	trace_create_file("error_log", TRACE_MODE_WRITE, d_tracer,
 			  tr, &tracing_err_log_fops);
 
 	for_each_tracing_cpu(cpu)
@@ -9675,19 +9652,19 @@ static __init int tracer_init_tracefs(void)
 	init_tracer_tracefs(&global_trace, NULL);
 	ftrace_init_tracefs_toplevel(&global_trace, NULL);
 
-	trace_create_file("tracing_thresh", 0644, NULL,
+	trace_create_file("tracing_thresh", TRACE_MODE_WRITE, NULL,
 			&global_trace, &tracing_thresh_fops);
 
-	trace_create_file("README", 0444, NULL,
+	trace_create_file("README", TRACE_MODE_READ, NULL,
 			NULL, &tracing_readme_fops);
 
-	trace_create_file("saved_cmdlines", 0444, NULL,
+	trace_create_file("saved_cmdlines", TRACE_MODE_READ, NULL,
 			NULL, &tracing_saved_cmdlines_fops);
 
-	trace_create_file("saved_cmdlines_size", 0644, NULL,
+	trace_create_file("saved_cmdlines_size", TRACE_MODE_WRITE, NULL,
 			  NULL, &tracing_saved_cmdlines_size_fops);
 
-	trace_create_file("saved_tgids", 0444, NULL,
+	trace_create_file("saved_tgids", TRACE_MODE_READ, NULL,
 			NULL, &tracing_saved_tgids_fops);
 
 	trace_eval_init();
@@ -9699,7 +9676,7 @@ static __init int tracer_init_tracefs(void)
 #endif
 
 #ifdef CONFIG_DYNAMIC_FTRACE
-	trace_create_file("dyn_ftrace_total_info", 0444, NULL,
+	trace_create_file("dyn_ftrace_total_info", TRACE_MODE_READ, NULL,
 			NULL, &tracing_dyn_info_fops);
 #endif