Merge tag 'trace-v5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:
 "The biggest change for this release is in the histogram code:

   - Add "onchange(var)" histogram handler that executes a action when
     $var changes.

   - Add new "snapshot()" action for histogram handlers, that causes a
     snapshot of the ring buffer when triggered. ie.
     onchange(var).snapshot() will trigger a snapshot if var changes.

   - Add alternative for "trace()" action. Currently, to trigger a
     synthetic event, the name of that event is used as the handler
     name, which is inconsistent with the other actions.
     onchange(var).synthetic(param) where it can now be
     onchange(var).trace(synthetic, param). The older method will still
     be allowed, as long as the synthetic events do not overlap with
     other handler names.

   - The histogram documentation at testcases were updated for the new
     changes.

  Outside of the histogram code, we have:

   - Added a quicker way to enable set_ftrace_filter files, that will
     make it much quicker to bisect tracing a function that shouldn't be
     traced and crashes the kernel. (You can echo in numbers to
     set_ftrace_filter, and it will select the corresponding function
     that is in available_filter_functions).

   - Some better displaying of the tracing data (and more information
     was added).

  The rest are small fixes and more clean ups to the code"

* tag 'trace-v5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (37 commits)
  tracing: Use strncpy instead of memcpy when copying comm in trace.c
  tracing: Use strncpy instead of memcpy when copying comm for hist triggers
  tracing: Use strncpy instead of memcpy for string keys in hist triggers
  tracing: Use str_has_prefix() in synth_event_create()
  x86/ftrace: Fix warning and considate ftrace_jmp_replace() and ftrace_call_replace()
  tracing/perf: Use strndup_user() instead of buggy open-coded version
  doc: trace: Fix documentation for uprobe_profile
  tracing: Fix spelling mistake: "analagous" -> "analogous"
  tracing: Comment why cond_snapshot is checked outside of max_lock protection
  tracing: Add hist trigger action 'expected fail' test case
  tracing: Add alternative synthetic event trace action test case
  tracing: Add hist trigger onchange() handler test case
  tracing: Add hist trigger snapshot() action test case
  tracing: Add SPDX license GPL-2.0 license identifier to inter-event testcases
  tracing: Add alternative synthetic event trace action syntax
  tracing: Add hist trigger onchange() handler Documentation
  tracing: Add hist trigger onchange() handler
  tracing: Add hist trigger snapshot() action Documentation
  tracing: Add hist trigger snapshot() action
  tracing: Add conditional snapshot
  ...

Documentation/trace/ftrace.rst

@@ -233,6 +233,12 @@ of ftrace. Here is a list of some of the key files:
 	This interface also allows for commands to be used. See the
 	"Filter commands" section for more details.
 
+	As a speed up, since processing strings can't be quite expensive
+	and requires a check of all functions registered to tracing, instead
+	an index can be written into this file. A number (starting with "1")
+	written will instead select the same corresponding at the line position
+	of the "available_filter_functions" file.
+
   set_ftrace_notrace:
 
 	This has an effect opposite to that of
@@ -1396,6 +1402,57 @@ enabling function tracing, we incur an added overhead. This
 overhead may extend the latency times. But nevertheless, this
 trace has provided some very helpful debugging information.
 
+If we prefer function graph output instead of function, we can set
+display-graph option::
+ with echo 1 > options/display-graph
+
+  # tracer: irqsoff
+  #
+  # irqsoff latency trace v1.1.5 on 4.20.0-rc6+
+  # --------------------------------------------------------------------
+  # latency: 3751 us, #274/274, CPU#0 | (M:desktop VP:0, KP:0, SP:0 HP:0 #P:4)
+  #    -----------------
+  #    | task: bash-1507 (uid:0 nice:0 policy:0 rt_prio:0)
+  #    -----------------
+  #  => started at: free_debug_processing
+  #  => ended at:   return_to_handler
+  #
+  #
+  #                                       _-----=> irqs-off
+  #                                      / _----=> need-resched
+  #                                     | / _---=> hardirq/softirq
+  #                                     || / _--=> preempt-depth
+  #                                     ||| /
+  #   REL TIME      CPU  TASK/PID       ||||     DURATION                  FUNCTION CALLS
+  #      |          |     |    |        ||||      |   |                     |   |   |   |
+          0 us |   0)   bash-1507    |  d... |   0.000 us    |  _raw_spin_lock_irqsave();
+          0 us |   0)   bash-1507    |  d..1 |   0.378 us    |    do_raw_spin_trylock();
+          1 us |   0)   bash-1507    |  d..2 |               |    set_track() {
+          2 us |   0)   bash-1507    |  d..2 |               |      save_stack_trace() {
+          2 us |   0)   bash-1507    |  d..2 |               |        __save_stack_trace() {
+          3 us |   0)   bash-1507    |  d..2 |               |          __unwind_start() {
+          3 us |   0)   bash-1507    |  d..2 |               |            get_stack_info() {
+          3 us |   0)   bash-1507    |  d..2 |   0.351 us    |              in_task_stack();
+          4 us |   0)   bash-1507    |  d..2 |   1.107 us    |            }
+  [...]
+       3750 us |   0)   bash-1507    |  d..1 |   0.516 us    |      do_raw_spin_unlock();
+       3750 us |   0)   bash-1507    |  d..1 |   0.000 us    |  _raw_spin_unlock_irqrestore();
+       3764 us |   0)   bash-1507    |  d..1 |   0.000 us    |  tracer_hardirqs_on();
+      bash-1507    0d..1 3792us : <stack trace>
+   => free_debug_processing
+   => __slab_free
+   => kmem_cache_free
+   => vm_area_free
+   => remove_vma
+   => exit_mmap
+   => mmput
+   => flush_old_exec
+   => load_elf_binary
+   => search_binary_handler
+   => __do_execve_file.isra.32
+   => __x64_sys_execve
+   => do_syscall_64
+   => entry_SYSCALL_64_after_hwframe
 
 preemptoff
 ----------
@@ -2784,6 +2841,38 @@ Produces::
 
 We can see that there's no more lock or preempt tracing.
 
+Selecting function filters via index
+------------------------------------
+
+Because processing of strings is expensive (the address of the function
+needs to be looked up before comparing to the string being passed in),
+an index can be used as well to enable functions. This is useful in the
+case of setting thousands of specific functions at a time. By passing
+in a list of numbers, no string processing will occur. Instead, the function
+at the specific location in the internal array (which corresponds to the
+functions in the "available_filter_functions" file), is selected.
+
+::
+
+  # echo 1 > set_ftrace_filter
+
+Will select the first function listed in "available_filter_functions"
+
+::
+
+  # head -1 available_filter_functions
+  trace_initcall_finish_cb
+
+  # cat set_ftrace_filter
+  trace_initcall_finish_cb
+
+  # head -50 available_filter_functions | tail -1
+  x86_pmu_commit_txn
+
+  # echo 1 50 > set_ftrace_filter
+  # cat set_ftrace_filter
+  trace_initcall_finish_cb
+  x86_pmu_commit_txn
 
 Dynamic ftrace with the function graph tracer
 ---------------------------------------------

Documentation/trace/uprobetracer.rst

@@ -73,10 +73,9 @@ For $comm, the default type is "string"; any other type is invalid.
 
 Event Profiling
 ---------------
-You can check the total number of probe hits and probe miss-hits via
-/sys/kernel/debug/tracing/uprobe_profile.
-The first column is event name, the second is the number of probe hits,
-the third is the number of probe miss-hits.
+You can check the total number of probe hits per event via
+/sys/kernel/debug/tracing/uprobe_profile. The first column is the filename,
+the second is the event name, the third is the number of probe hits.
 
 Usage examples
 --------------

arch/x86/kernel/ftrace.c

@@ -49,7 +49,7 @@ int ftrace_arch_code_modify_post_process(void)
 union ftrace_code_union {
 	char code[MCOUNT_INSN_SIZE];
 	struct {
-		unsigned char e8;
+		unsigned char op;
 		int offset;
 	} __attribute__((packed));
 };
@@ -59,20 +59,23 @@ static int ftrace_calc_offset(long ip, long addr)
 	return (int)(addr - ip);
 }
 
-static unsigned char *ftrace_call_replace(unsigned long ip, unsigned long addr)
+static unsigned char *
+ftrace_text_replace(unsigned char op, unsigned long ip, unsigned long addr)
 {
 	static union ftrace_code_union calc;
 
-	calc.e8		= 0xe8;
+	calc.op		= op;
 	calc.offset	= ftrace_calc_offset(ip + MCOUNT_INSN_SIZE, addr);
 
-	/*
-	 * No locking needed, this must be called via kstop_machine
-	 * which in essence is like running on a uniprocessor machine.
-	 */
 	return calc.code;
 }
 
+static unsigned char *
+ftrace_call_replace(unsigned long ip, unsigned long addr)
+{
+	return ftrace_text_replace(0xe8, ip, addr);
+}
+
 static inline int
 within(unsigned long addr, unsigned long start, unsigned long end)
 {
@@ -665,22 +668,6 @@ int __init ftrace_dyn_arch_init(void)
 	return 0;
 }
 
-#if defined(CONFIG_X86_64) || defined(CONFIG_FUNCTION_GRAPH_TRACER)
-static unsigned char *ftrace_jmp_replace(unsigned long ip, unsigned long addr)
-{
-	static union ftrace_code_union calc;
-
-	/* Jmp not a call (ignore the .e8) */
-	calc.e8		= 0xe9;
-	calc.offset	= ftrace_calc_offset(ip + MCOUNT_INSN_SIZE, addr);
-
-	/*
-	 * ftrace external locks synchronize the access to the static variable.
-	 */
-	return calc.code;
-}
-#endif
-
 /* Currently only x86_64 supports dynamic trampolines */
 #ifdef CONFIG_X86_64
 
@@ -892,8 +879,8 @@ static void *addr_from_call(void *ptr)
 		return NULL;
 
 	/* Make sure this is a call */
-	if (WARN_ON_ONCE(calc.e8 != 0xe8)) {
-		pr_warn("Expected e8, got %x\n", calc.e8);
+	if (WARN_ON_ONCE(calc.op != 0xe8)) {
+		pr_warn("Expected e8, got %x\n", calc.op);
 		return NULL;
 	}
 
@@ -964,6 +951,11 @@ void arch_ftrace_trampoline_free(struct ftrace_ops *ops)
 #ifdef CONFIG_DYNAMIC_FTRACE
 extern void ftrace_graph_call(void);
 
+static unsigned char *ftrace_jmp_replace(unsigned long ip, unsigned long addr)
+{
+	return ftrace_text_replace(0xe9, ip, addr);
+}
+
 static int ftrace_mod_jmp(unsigned long ip, void *func)
 {
 	unsigned char *new;

include/linux/ring_buffer.h

@@ -187,8 +187,6 @@ void ring_buffer_set_clock(struct ring_buffer *buffer,
 void ring_buffer_set_time_stamp_abs(struct ring_buffer *buffer, bool abs);
 bool ring_buffer_time_stamp_abs(struct ring_buffer *buffer);
 
-size_t ring_buffer_page_len(void *page);
-
 size_t ring_buffer_nr_pages(struct ring_buffer *buffer, int cpu);
 size_t ring_buffer_nr_dirty_pages(struct ring_buffer *buffer, int cpu);
 

kernel/events/uprobes.c

@@ -53,7 +53,7 @@ static struct percpu_rw_semaphore dup_mmap_sem;
 
 struct uprobe {
 	struct rb_node		rb_node;	/* node in the rb tree */
-	atomic_t		ref;
+	refcount_t		ref;
 	struct rw_semaphore	register_rwsem;
 	struct rw_semaphore	consumer_rwsem;
 	struct list_head	pending_list;
@@ -547,13 +547,13 @@ set_orig_insn(struct arch_uprobe *auprobe, struct mm_struct *mm, unsigned long v
 
 static struct uprobe *get_uprobe(struct uprobe *uprobe)
 {
-	atomic_inc(&uprobe->ref);
+	refcount_inc(&uprobe->ref);
 	return uprobe;
 }
 
 static void put_uprobe(struct uprobe *uprobe)
 {
-	if (atomic_dec_and_test(&uprobe->ref)) {
+	if (refcount_dec_and_test(&uprobe->ref)) {
 		/*
 		 * If application munmap(exec_vma) before uprobe_unregister()
 		 * gets called, we don't get a chance to remove uprobe from
@@ -644,7 +644,7 @@ static struct uprobe *__insert_uprobe(struct uprobe *uprobe)
 	rb_link_node(&uprobe->rb_node, parent, p);
 	rb_insert_color(&uprobe->rb_node, &uprobes_tree);
 	/* get access + creation ref */
-	atomic_set(&uprobe->ref, 2);
+	refcount_set(&uprobe->ref, 2);
 
 	return u;
 }

kernel/trace/ftrace.c

@@ -3701,6 +3701,31 @@ enter_record(struct ftrace_hash *hash, struct dyn_ftrace *rec, int clear_filter)
 	return ret;
 }
 
+static int
+add_rec_by_index(struct ftrace_hash *hash, struct ftrace_glob *func_g,
+		 int clear_filter)
+{
+	long index = simple_strtoul(func_g->search, NULL, 0);
+	struct ftrace_page *pg;
+	struct dyn_ftrace *rec;
+
+	/* The index starts at 1 */
+	if (--index < 0)
+		return 0;
+
+	do_for_each_ftrace_rec(pg, rec) {
+		if (pg->index <= index) {
+			index -= pg->index;
+			/* this is a double loop, break goes to the next page */
+			break;
+		}
+		rec = &pg->records[index];
+		enter_record(hash, rec, clear_filter);
+		return 1;
+	} while_for_each_ftrace_rec();
+	return 0;
+}
+
 static int
 ftrace_match_record(struct dyn_ftrace *rec, struct ftrace_glob *func_g,
 		struct ftrace_glob *mod_g, int exclude_mod)
@@ -3769,6 +3794,11 @@ match_records(struct ftrace_hash *hash, char *func, int len, char *mod)
 	if (unlikely(ftrace_disabled))
 		goto out_unlock;
 
+	if (func_g.type == MATCH_INDEX) {
+		found = add_rec_by_index(hash, &func_g, clear_filter);
+		goto out_unlock;
+	}
+
 	do_for_each_ftrace_rec(pg, rec) {
 
 		if (rec->flags & FTRACE_FL_DISABLED)

kernel/trace/ring_buffer.c

@@ -353,20 +353,6 @@ static void rb_init_page(struct buffer_data_page *bpage)
 	local_set(&bpage->commit, 0);
 }
 
-/**
- * ring_buffer_page_len - the size of data on the page.
- * @page: The page to read
- *
- * Returns the amount of data on the page, including buffer page header.
- */
-size_t ring_buffer_page_len(void *page)
-{
-	struct buffer_data_page *bpage = page;
-
-	return (local_read(&bpage->commit) & ~RB_MISSED_FLAGS)
-		+ BUF_PAGE_HDR_SIZE;
-}
-
 /*
  * Also stolen from mm/slob.c. Thanks to Mathieu Desnoyers for pointing
  * this issue out.

kernel/trace/trace.h

@@ -194,6 +194,51 @@ struct trace_pid_list {
 	unsigned long			*pids;
 };
 
+typedef bool (*cond_update_fn_t)(struct trace_array *tr, void *cond_data);
+
+/**
+ * struct cond_snapshot - conditional snapshot data and callback
+ *
+ * The cond_snapshot structure encapsulates a callback function and
+ * data associated with the snapshot for a given tracing instance.
+ *
+ * When a snapshot is taken conditionally, by invoking
+ * tracing_snapshot_cond(tr, cond_data), the cond_data passed in is
+ * passed in turn to the cond_snapshot.update() function.  That data
+ * can be compared by the update() implementation with the cond_data
+ * contained wihin the struct cond_snapshot instance associated with
+ * the trace_array.  Because the tr->max_lock is held throughout the
+ * update() call, the update() function can directly retrieve the
+ * cond_snapshot and cond_data associated with the per-instance
+ * snapshot associated with the trace_array.
+ *
+ * The cond_snapshot.update() implementation can save data to be
+ * associated with the snapshot if it decides to, and returns 'true'
+ * in that case, or it returns 'false' if the conditional snapshot
+ * shouldn't be taken.
+ *
+ * The cond_snapshot instance is created and associated with the
+ * user-defined cond_data by tracing_cond_snapshot_enable().
+ * Likewise, the cond_snapshot instance is destroyed and is no longer
+ * associated with the trace instance by
+ * tracing_cond_snapshot_disable().
+ *
+ * The method below is required.
+ *
+ * @update: When a conditional snapshot is invoked, the update()
+ *	callback function is invoked with the tr->max_lock held.  The
+ *	update() implementation signals whether or not to actually
+ *	take the snapshot, by returning 'true' if so, 'false' if no
+ *	snapshot should be taken.  Because the max_lock is held for
+ *	the duration of update(), the implementation is safe to
+ *	directly retrieven and save any implementation data it needs
+ *	to in association with the snapshot.
+ */
+struct cond_snapshot {
+	void				*cond_data;
+	cond_update_fn_t		update;
+};
+
 /*
  * The trace array - an array of per-CPU trace arrays. This is the
  * highest level data structure that individual tracers deal with.
@@ -277,6 +322,9 @@ struct trace_array {
 #endif
 	int			time_stamp_abs_ref;
 	struct list_head	hist_vars;
+#ifdef CONFIG_TRACER_SNAPSHOT
+	struct cond_snapshot	*cond_snapshot;
+#endif
 };
 
 enum {
@@ -727,7 +775,8 @@ int trace_pid_write(struct trace_pid_list *filtered_pids,
 		    const char __user *ubuf, size_t cnt);
 
 #ifdef CONFIG_TRACER_MAX_TRACE
-void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
+void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu,
+		   void *cond_data);
 void update_max_tr_single(struct trace_array *tr,
 			  struct task_struct *tsk, int cpu);
 #endif /* CONFIG_TRACER_MAX_TRACE */
@@ -855,10 +904,11 @@ static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash)
 #define TRACE_GRAPH_PRINT_PROC          0x8
 #define TRACE_GRAPH_PRINT_DURATION      0x10
 #define TRACE_GRAPH_PRINT_ABS_TIME      0x20
-#define TRACE_GRAPH_PRINT_IRQS          0x40
-#define TRACE_GRAPH_PRINT_TAIL          0x80
-#define TRACE_GRAPH_SLEEP_TIME		0x100
-#define TRACE_GRAPH_GRAPH_TIME		0x200
+#define TRACE_GRAPH_PRINT_REL_TIME      0x40
+#define TRACE_GRAPH_PRINT_IRQS          0x80
+#define TRACE_GRAPH_PRINT_TAIL          0x100
+#define TRACE_GRAPH_SLEEP_TIME          0x200
+#define TRACE_GRAPH_GRAPH_TIME          0x400
 #define TRACE_GRAPH_PRINT_FILL_SHIFT	28
 #define TRACE_GRAPH_PRINT_FILL_MASK	(0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT)
 
@@ -1458,6 +1508,7 @@ enum regex_type {
 	MATCH_MIDDLE_ONLY,
 	MATCH_END_ONLY,
 	MATCH_GLOB,
+	MATCH_INDEX,
 };
 
 struct regex {
@@ -1808,6 +1859,11 @@ static inline bool event_command_needs_rec(struct event_command *cmd_ops)
 extern int trace_event_enable_disable(struct trace_event_file *file,
 				      int enable, int soft_disable);
 extern int tracing_alloc_snapshot(void);
+extern void tracing_snapshot_cond(struct trace_array *tr, void *cond_data);
+extern int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data, cond_update_fn_t update);
+
+extern int tracing_snapshot_cond_disable(struct trace_array *tr);
+extern void *tracing_cond_snapshot_data(struct trace_array *tr);
 
 extern const char *__start___trace_bprintk_fmt[];
 extern const char *__stop___trace_bprintk_fmt[];

kernel/trace/trace_entries.h

@@ -65,7 +65,8 @@ FTRACE_ENTRY_REG(function, ftrace_entry,
 		__field(	unsigned long,	parent_ip	)
 	),
 
-	F_printk(" %lx <-- %lx", __entry->ip, __entry->parent_ip),
+	F_printk(" %ps <-- %ps",
+		 (void *)__entry->ip, (void *)__entry->parent_ip),
 
 	FILTER_TRACE_FN,
 
@@ -83,7 +84,7 @@ FTRACE_ENTRY_PACKED(funcgraph_entry, ftrace_graph_ent_entry,
 		__field_desc(	int,		graph_ent,	depth		)
 	),
 
-	F_printk("--> %lx (%d)", __entry->func, __entry->depth),
+	F_printk("--> %ps (%d)", (void *)__entry->func, __entry->depth),
 
 	FILTER_OTHER
 );
@@ -102,8 +103,8 @@ FTRACE_ENTRY_PACKED(funcgraph_exit, ftrace_graph_ret_entry,
 		__field_desc(	int,		ret,		depth	)
 	),
 
-	F_printk("<-- %lx (%d) (start: %llx  end: %llx) over: %d",
-		 __entry->func, __entry->depth,
+	F_printk("<-- %ps (%d) (start: %llx  end: %llx) over: %d",
+		 (void *)__entry->func, __entry->depth,
 		 __entry->calltime, __entry->rettime,
 		 __entry->depth),
 
@@ -167,12 +168,6 @@ FTRACE_ENTRY_DUP(wakeup, ctx_switch_entry,
 
 #define FTRACE_STACK_ENTRIES	8
 
-#ifndef CONFIG_64BIT
-# define IP_FMT "%08lx"
-#else
-# define IP_FMT "%016lx"
-#endif
-
 FTRACE_ENTRY(kernel_stack, stack_entry,
 
 	TRACE_STACK,
@@ -182,12 +177,13 @@ FTRACE_ENTRY(kernel_stack, stack_entry,
 		__dynamic_array(unsigned long,	caller	)
 	),
 
-	F_printk("\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n"
-		 "\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n"
-		 "\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n",
-		 __entry->caller[0], __entry->caller[1], __entry->caller[2],
-		 __entry->caller[3], __entry->caller[4], __entry->caller[5],
-		 __entry->caller[6], __entry->caller[7]),
+	F_printk("\t=> %ps\n\t=> %ps\n\t=> %ps\n"
+		 "\t=> %ps\n\t=> %ps\n\t=> %ps\n"
+		 "\t=> %ps\n\t=> %ps\n",
+		 (void *)__entry->caller[0], (void *)__entry->caller[1],
+		 (void *)__entry->caller[2], (void *)__entry->caller[3],
+		 (void *)__entry->caller[4], (void *)__entry->caller[5],
+		 (void *)__entry->caller[6], (void *)__entry->caller[7]),
 
 	FILTER_OTHER
 );
@@ -201,12 +197,13 @@ FTRACE_ENTRY(user_stack, userstack_entry,
 		__array(	unsigned long,	caller, FTRACE_STACK_ENTRIES	)
 	),
 
-	F_printk("\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n"
-		 "\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n"
-		 "\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n",
-		 __entry->caller[0], __entry->caller[1], __entry->caller[2],
-		 __entry->caller[3], __entry->caller[4], __entry->caller[5],
-		 __entry->caller[6], __entry->caller[7]),
+	F_printk("\t=> %ps\n\t=> %ps\n\t=> %ps\n"
+		 "\t=> %ps\n\t=> %ps\n\t=> %ps\n"
+		 "\t=> %ps\n\t=> %ps\n",
+		 (void *)__entry->caller[0], (void *)__entry->caller[1],
+		 (void *)__entry->caller[2], (void *)__entry->caller[3],
+		 (void *)__entry->caller[4], (void *)__entry->caller[5],
+		 (void *)__entry->caller[6], (void *)__entry->caller[7]),
 
 	FILTER_OTHER
 );

kernel/trace/trace_event_perf.c

@@ -299,15 +299,13 @@ int perf_uprobe_init(struct perf_event *p_event,
 
 	if (!p_event->attr.uprobe_path)
 		return -EINVAL;
-	path = kzalloc(PATH_MAX, GFP_KERNEL);
-	if (!path)
-		return -ENOMEM;
-	ret = strncpy_from_user(
-		path, u64_to_user_ptr(p_event->attr.uprobe_path), PATH_MAX);
-	if (ret == PATH_MAX)
-		return -E2BIG;
-	if (ret < 0)
-		goto out;
+
+	path = strndup_user(u64_to_user_ptr(p_event->attr.uprobe_path),
+			    PATH_MAX);
+	if (IS_ERR(path)) {
+		ret = PTR_ERR(path);
+		return (ret == -EINVAL) ? -E2BIG : ret;
+	}
 	if (path[0] == '\0') {
 		ret = -EINVAL;
 		goto out;

kernel/trace/trace_events_filter.c

@@ -491,10 +491,12 @@ predicate_parse(const char *str, int nr_parens, int nr_preds,
 				break;
 			case '&':
 			case '|':
+				/* accepting only "&&" or "||" */
 				if (next[1] == next[0]) {
 					ptr++;
 					break;
 				}
+				/* fall through */
 			default:
 				parse_error(pe, FILT_ERR_TOO_MANY_PREDS,
 					    next - str);
@@ -823,6 +825,9 @@ enum regex_type filter_parse_regex(char *buff, int len, char **search, int *not)
 
 	*search = buff;
 
+	if (isdigit(buff[0]))
+		return MATCH_INDEX;
+
 	for (i = 0; i < len; i++) {
 		if (buff[i] == '*') {
 			if (!i) {
@@ -860,6 +865,8 @@ static void filter_build_regex(struct filter_pred *pred)
 	}
 
 	switch (type) {
+	/* MATCH_INDEX should not happen, but if it does, match full */
+	case MATCH_INDEX:
 	case MATCH_FULL:
 		r->match = regex_match_full;
 		break;

kernel/trace/trace_functions_graph.c

@@ -380,6 +380,7 @@ static void print_graph_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
 {
 	trace_seq_putc(s, ' ');
 	trace_print_lat_fmt(s, entry);
+	trace_seq_puts(s, " | ");
 }
 
 /* If the pid changed since the last trace, output this event */
@@ -500,6 +501,17 @@ static void print_graph_abs_time(u64 t, struct trace_seq *s)
 			 (unsigned long)t, usecs_rem);
 }
 
+static void
+print_graph_rel_time(struct trace_iterator *iter, struct trace_seq *s)
+{
+	unsigned long long usecs;
+
+	usecs = iter->ts - iter->trace_buffer->time_start;
+	do_div(usecs, NSEC_PER_USEC);
+
+	trace_seq_printf(s, "%9llu us |  ", usecs);
+}
+
 static void
 print_graph_irq(struct trace_iterator *iter, unsigned long addr,
 		enum trace_type type, int cpu, pid_t pid, u32 flags)
@@ -517,6 +529,10 @@ print_graph_irq(struct trace_iterator *iter, unsigned long addr,
 		if (flags & TRACE_GRAPH_PRINT_ABS_TIME)
 			print_graph_abs_time(iter->ts, s);
 
+		/* Relative time */
+		if (flags & TRACE_GRAPH_PRINT_REL_TIME)
+			print_graph_rel_time(iter, s);
+
 		/* Cpu */
 		if (flags & TRACE_GRAPH_PRINT_CPU)
 			print_graph_cpu(s, cpu);
@@ -725,6 +741,10 @@ print_graph_prologue(struct trace_iterator *iter, struct trace_seq *s,
 	if (flags & TRACE_GRAPH_PRINT_ABS_TIME)
 		print_graph_abs_time(iter->ts, s);
 
+	/* Relative time */
+	if (flags & TRACE_GRAPH_PRINT_REL_TIME)
+		print_graph_rel_time(iter, s);
+
 	/* Cpu */
 	if (flags & TRACE_GRAPH_PRINT_CPU)
 		print_graph_cpu(s, cpu);
@@ -1101,6 +1121,8 @@ static void print_lat_header(struct seq_file *s, u32 flags)
 
 	if (flags & TRACE_GRAPH_PRINT_ABS_TIME)
 		size += 16;
+	if (flags & TRACE_GRAPH_PRINT_REL_TIME)
+		size += 16;
 	if (flags & TRACE_GRAPH_PRINT_CPU)
 		size += 4;
 	if (flags & TRACE_GRAPH_PRINT_PROC)
@@ -1125,12 +1147,14 @@ static void __print_graph_headers_flags(struct trace_array *tr,
 	seq_putc(s, '#');
 	if (flags & TRACE_GRAPH_PRINT_ABS_TIME)
 		seq_puts(s, "     TIME       ");
+	if (flags & TRACE_GRAPH_PRINT_REL_TIME)
+		seq_puts(s, "   REL TIME     ");
 	if (flags & TRACE_GRAPH_PRINT_CPU)
 		seq_puts(s, " CPU");
 	if (flags & TRACE_GRAPH_PRINT_PROC)
 		seq_puts(s, "  TASK/PID       ");
 	if (lat)
-		seq_puts(s, "||||");
+		seq_puts(s, "||||   ");
 	if (flags & TRACE_GRAPH_PRINT_DURATION)
 		seq_puts(s, "  DURATION   ");
 	seq_puts(s, "               FUNCTION CALLS\n");
@@ -1139,12 +1163,14 @@ static void __print_graph_headers_flags(struct trace_array *tr,
 	seq_putc(s, '#');
 	if (flags & TRACE_GRAPH_PRINT_ABS_TIME)
 		seq_puts(s, "      |         ");
+	if (flags & TRACE_GRAPH_PRINT_REL_TIME)
+		seq_puts(s, "      |         ");
 	if (flags & TRACE_GRAPH_PRINT_CPU)
 		seq_puts(s, " |  ");
 	if (flags & TRACE_GRAPH_PRINT_PROC)
 		seq_puts(s, "   |    |        ");
 	if (lat)
-		seq_puts(s, "||||");
+		seq_puts(s, "||||   ");
 	if (flags & TRACE_GRAPH_PRINT_DURATION)
 		seq_puts(s, "   |   |      ");
 	seq_puts(s, "               |   |   |   |\n");

kernel/trace/trace_irqsoff.c

@@ -239,7 +239,7 @@ static void irqsoff_trace_close(struct trace_iterator *iter)
 
 #define GRAPH_TRACER_FLAGS (TRACE_GRAPH_PRINT_CPU | \
 			    TRACE_GRAPH_PRINT_PROC | \
-			    TRACE_GRAPH_PRINT_ABS_TIME | \
+			    TRACE_GRAPH_PRINT_REL_TIME | \
 			    TRACE_GRAPH_PRINT_DURATION)
 
 static enum print_line_t irqsoff_print_line(struct trace_iterator *iter)

kernel/trace/trace_probe.c

@@ -300,6 +300,7 @@ parse_probe_arg(char *arg, const struct fetch_type *type,
 
 	case '+':	/* deref memory */
 		arg++;	/* Skip '+', because kstrtol() rejects it. */
+		/* fall through */
 	case '-':
 		tmp = strchr(arg, '(');
 		if (!tmp)

kernel/trace/trace_sched_wakeup.c

@@ -180,8 +180,11 @@ static void wakeup_trace_close(struct trace_iterator *iter)
 }
 
 #define GRAPH_TRACER_FLAGS (TRACE_GRAPH_PRINT_PROC | \
-			    TRACE_GRAPH_PRINT_ABS_TIME | \
-			    TRACE_GRAPH_PRINT_DURATION)
+			    TRACE_GRAPH_PRINT_CPU |  \
+			    TRACE_GRAPH_PRINT_REL_TIME | \
+			    TRACE_GRAPH_PRINT_DURATION | \
+			    TRACE_GRAPH_PRINT_OVERHEAD | \
+			    TRACE_GRAPH_PRINT_IRQS)
 
 static enum print_line_t wakeup_print_line(struct trace_iterator *iter)
 {
@@ -472,6 +475,7 @@ probe_wakeup_sched_switch(void *ignore, bool preempt,
 
 	__trace_function(wakeup_trace, CALLER_ADDR0, CALLER_ADDR1, flags, pc);
 	tracing_sched_switch_trace(wakeup_trace, prev, next, flags, pc);
+	__trace_stack(wakeup_trace, flags, 0, pc);
 
 	T0 = data->preempt_timestamp;
 	T1 = ftrace_now(cpu);
@@ -482,7 +486,7 @@ probe_wakeup_sched_switch(void *ignore, bool preempt,
 
 	if (likely(!is_tracing_stopped())) {
 		wakeup_trace->max_latency = delta;
-		update_max_tr(wakeup_trace, wakeup_task, wakeup_cpu);
+		update_max_tr(wakeup_trace, wakeup_task, wakeup_cpu, NULL);
 	}
 
 out_unlock:
@@ -583,6 +587,7 @@ probe_wakeup(void *ignore, struct task_struct *p)
 	data = per_cpu_ptr(wakeup_trace->trace_buffer.data, wakeup_cpu);
 	data->preempt_timestamp = ftrace_now(cpu);
 	tracing_sched_wakeup_trace(wakeup_trace, p, current, flags, pc);
+	__trace_stack(wakeup_trace, flags, 0, pc);
 
 	/*
 	 * We must be careful in using CALLER_ADDR2. But since wake_up

tools/testing/selftests/ftrace/test.d/trigger/inter-event/trigger-action-hist-xfail.tc

+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# description: event trigger - test inter-event histogram trigger expected fail actions
+
+fail() { #msg
+    echo $1
+    exit_fail
+}
+
+if [ ! -f set_event ]; then
+    echo "event tracing is not supported"
+    exit_unsupported
+fi
+
+if [ ! -f snapshot ]; then
+    echo "snapshot is not supported"
+    exit_unsupported
+fi
+
+grep -q "snapshot()" README || exit_unsupported # version issue
+
+echo "Test expected snapshot action failure"
+
+echo 'hist:keys=comm:onmatch(sched.sched_wakeup).snapshot()' >> /sys/kernel/debug/tracing/events/sched/sched_waking/trigger && exit_fail
+
+echo "Test expected save action failure"
+
+echo 'hist:keys=comm:onmatch(sched.sched_wakeup).save(comm,prio)' >> /sys/kernel/debug/tracing/events/sched/sched_waking/trigger && exit_fail
+
+exit_xfail

tools/testing/selftests/ftrace/test.d/trigger/inter-event/trigger-extended-error-support.tc

 #!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
 # description: event trigger - test extended error support
 
 

tools/testing/selftests/ftrace/test.d/trigger/inter-event/trigger-field-variable-support.tc

 #!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
 # description: event trigger - test field variable support
 
 fail() { #msg

tools/testing/selftests/ftrace/test.d/trigger/inter-event/trigger-inter-event-combined-hist.tc

 #!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
 # description: event trigger - test inter-event combined histogram trigger
 
 fail() { #msg

tools/testing/selftests/ftrace/test.d/trigger/inter-event/trigger-multi-actions-accept.tc

 #!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
 # description: event trigger - test multiple actions on hist trigger
 
 fail() { #msg

tools/testing/selftests/ftrace/test.d/trigger/inter-event/trigger-onchange-action-hist.tc

+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# description: event trigger - test inter-event histogram trigger onchange action
+
+fail() { #msg
+    echo $1
+    exit_fail
+}
+
+if [ ! -f set_event ]; then
+    echo "event tracing is not supported"
+    exit_unsupported
+fi
+
+grep -q "onchange(var)" README || exit_unsupported # version issue
+
+echo "Test onchange action"
+
+echo 'hist:keys=comm:newprio=prio:onchange($newprio).save(comm,prio) if comm=="ping"' >> /sys/kernel/debug/tracing/events/sched/sched_waking/trigger
+
+ping $LOCALHOST -c 3
+nice -n 1 ping $LOCALHOST -c 3
+
+if ! grep -q "changed:" events/sched/sched_waking/hist; then
+    fail "Failed to create onchange action inter-event histogram"
+fi
+
+exit 0

tools/testing/selftests/ftrace/test.d/trigger/inter-event/trigger-onmatch-action-hist.tc

 #!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
 # description: event trigger - test inter-event histogram trigger onmatch action
 
 fail() { #msg

tools/testing/selftests/ftrace/test.d/trigger/inter-event/trigger-onmatch-onmax-action-hist.tc

 #!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
 # description: event trigger - test inter-event histogram trigger onmatch-onmax action
 
 fail() { #msg

tools/testing/selftests/ftrace/test.d/trigger/inter-event/trigger-onmax-action-hist.tc

 #!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
 # description: event trigger - test inter-event histogram trigger onmax action
 
 fail() { #msg

tools/testing/selftests/ftrace/test.d/trigger/inter-event/trigger-snapshot-action-hist.tc

+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# description: event trigger - test inter-event histogram trigger snapshot action
+
+fail() { #msg
+    echo $1
+    exit_fail
+}
+
+if [ ! -f set_event ]; then
+    echo "event tracing is not supported"
+    exit_unsupported
+fi
+
+if [ ! -f snapshot ]; then
+    echo "snapshot is not supported"
+    exit_unsupported
+fi
+
+grep -q "onchange(var)" README || exit_unsupported # version issue
+
+grep -q "snapshot()" README || exit_unsupported # version issue
+
+echo "Test snapshot action"
+
+echo 1 > /sys/kernel/debug/tracing/events/sched/enable
+
+echo 'hist:keys=comm:newprio=prio:onchange($newprio).save(comm,prio):onchange($newprio).snapshot() if comm=="ping"' >> /sys/kernel/debug/tracing/events/sched/sched_waking/trigger
+
+ping $LOCALHOST -c 3
+nice -n 1 ping $LOCALHOST -c 3
+
+echo 0 > tracing_on
+
+if ! grep -q "changed:" events/sched/sched_waking/hist; then
+    fail "Failed to create onchange action inter-event histogram"
+fi
+
+if ! grep -q "comm=ping" snapshot; then
+    fail "Failed to create snapshot action inter-event histogram"
+fi
+
+exit 0

tools/testing/selftests/ftrace/test.d/trigger/inter-event/trigger-synthetic-event-createremove.tc

 #!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
 # description: event trigger - test synthetic event create remove
 
 fail() { #msg

tools/testing/selftests/ftrace/test.d/trigger/inter-event/trigger-trace-action-hist.tc

+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# description: event trigger - test inter-event histogram trigger trace action
+
+fail() { #msg
+    echo $1
+    exit_fail
+}
+
+if [ ! -f set_event ]; then
+    echo "event tracing is not supported"
+    exit_unsupported
+fi
+
+if [ ! -f synthetic_events ]; then
+    echo "synthetic event is not supported"
+    exit_unsupported
+fi
+
+grep -q "trace(<synthetic_event>" README || exit_unsupported # version issue
+
+echo "Test create synthetic event"
+
+echo 'wakeup_latency  u64 lat pid_t pid char comm[16]' > synthetic_events
+if [ ! -d events/synthetic/wakeup_latency ]; then
+    fail "Failed to create wakeup_latency synthetic event"
+fi
+
+echo "Test create histogram for synthetic event using trace action"
+echo "Test histogram variables,simple expression support and trace action"
+
+echo 'hist:keys=pid:ts0=common_timestamp.usecs if comm=="ping"' > events/sched/sched_wakeup/trigger
+echo 'hist:keys=next_pid:wakeup_lat=common_timestamp.usecs-$ts0:onmatch(sched.sched_wakeup).trace(wakeup_latency,$wakeup_lat,next_pid,next_comm) if next_comm=="ping"' > events/sched/sched_switch/trigger
+echo 'hist:keys=comm,pid,lat:wakeup_lat=lat:sort=lat' > events/synthetic/wakeup_latency/trigger
+
+ping $LOCALHOST -c 5
+
+if ! grep -q "ping" events/synthetic/wakeup_latency/hist; then
+    fail "Failed to create trace action inter-event histogram"
+fi
+
+exit 0