Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Fix error output of boot instance creation failure

   Currently if a boot instance creation fails, instead of printing out
   the name of the instance that failed, it prints "(null)". That is
   because it prints "cur_str" that had already been processed by
   strsep(). Print the saved name instead.

   While at it, print the error code of the failure.

 - Fix use-after-free for same named historgrams

   Histograms can be named so that they can be used in multiple events.
   But if the named histogram has a variable attached, the second event
   that uses the named histogram which duplicates it and needs to free
   the original after duplication leaves the old variable in place and
   still visible. If another histogram uses than variable, it will use
   the stale one which will try to reference the freed duplicate
   histogram and crash the kernel.

   Free the duplicate variables along with the duplicated histogram
   data.

 - Check return value of kthread_run() in event self test

   The events self tests uses a kthread for testing but does not check
   if it succeeded in creating a kthread. If the kthread creation were
   to fail, the code will still try to call kthread_stop() on the error
   returned.

 - Fix race between reading trace_pipe and updating subbuffer size

   If a user is reading the trace_pipe file at the same time they update
   the ring buffer sub-buffer size, can cause the trace_pipe read to
   read stale data. Add trace_access_lock() around updating the ring
   buffer sub-buffer size.

 - Fix eventfs_inode on failure path in creation of the events directory

   In the creation of the "events" directory, if after allocating the
   eventfs_inode a failure is detected, it calls cleanup_ei() which
   calls free_ei(). The free_ei() will test if eventfs_inode being freed
   has no children. It is a bug if it does. But on the failure case of
   the creation of the "events" directory, the children lists have not
   yet been initialized and the free will trigger a warning because
   list_empty() on an uninitialized list returns false.

   Move the initialization into init_ei() where it makes more sense and
   makes sure that a created eventfs_inode has its lists initialized
   upon creation.

 - Check return value of kthread_run() in ftrace direct sample code

   The sample code that shows how to use the ftrace direct calls does
   not test the return of kthread_run() to see if it succeeds. Return a
   failure if the kthread_run() doesn't succeed.

 - Clear user events state on fork in case of alloc failure

   On fork, the child gets a pointer to the parent's user events state.
   It makes a copy of it then updates the child's pointer to it. But if
   the allocation fails, the duplication function leaves the child with
   a pointer to its parent's descriptor. When the child cleans up its
   data, it will free the parent's descriptor while the parent is still
   using it.

   In the duplication function, set the child's user_event_mm to NULL
   before testing if the allocation succeeded, and when it exits it will
   not free the parent's descriptor.

 - Fix retry exhaustion in simple ring buffer reader swap

   simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
   post-decrements it only after a failed link replacement. On the final
   attempt, a successful replacement leaves retry at zero, while a
   failed replacement leaves it at -1.

   But the check for success expects the retry value to be non-zero and
   exits with an error on zero. This is the opposite result. Fix it.

 - Fail nicely when the remote swap_reader_page() returns an error

   Currently, if the swap_reader_page() of a remote buffer fails, it
   triggers a WARN_ON_ONCE() and continues normally. Instead, have it
   exit with an error and a pr_warn() print instead of a full WARNING.

* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Stop remote reader update when page swap fails
  tracing: Fix retry exhaustion in simple ring buffer reader swap
  tracing/user_events: Clear copied tracing state before fork duplication
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
  eventfs: Initialize ei->children and ei->list in init_ei()
  tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
  tracing: Fix crash passing ERR_PTR to kthread_stop()
  tracing: Fix use-after-free with same-name named triggers
  tracing: Fix logged instance name on creation failure

6 files changed, 635 insertions, 0 deletions

diff --git a/tools/perf/ui/tui/Build b/tools/perf/ui/tui/Build
new file mode 100644
index 000000000..2ac058ad1
--- /dev/null
+++ b/tools/perf/ui/tui/Build
@@ -0,0 +1,4 @@
+perf-ui-y += setup.o
+perf-ui-y += util.o
+perf-ui-y += helpline.o
+perf-ui-y += progress.o
diff --git a/tools/perf/ui/tui/helpline.c b/tools/perf/ui/tui/helpline.c
new file mode 100644
index 000000000..b39451314
--- /dev/null
+++ b/tools/perf/ui/tui/helpline.c
@@ -0,0 +1,62 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+
+#include "../helpline.h"
+#include "../ui.h"
+#include "../libslang.h"
+
+char ui_helpline__last_msg[1024];
+bool tui_helpline__set;
+
+static void tui_helpline__pop(void)
+{
+}
+
+static void tui_helpline__push(const char *msg)
+{
+	const size_t sz = sizeof(ui_helpline__current);
+
+	SLsmg_gotorc(SLtt_Screen_Rows - 1, 0);
+	SLsmg_set_color(0);
+	SLsmg_write_nstring(msg, SLtt_Screen_Cols);
+	SLsmg_refresh();
+	strlcpy(ui_helpline__current, msg, sz);
+}
+
+static int tui_helpline__show(const char *format, va_list ap)
+{
+	int ret;
+	static int backlog;
+
+	mutex_lock(&ui__lock);
+	ret = vscnprintf(ui_helpline__last_msg + backlog,
+			sizeof(ui_helpline__last_msg) - backlog, format, ap);
+	backlog += ret;
+
+	tui_helpline__set = true;
+
+	if (ui_helpline__last_msg[backlog - 1] == '\n') {
+		ui_helpline__puts(ui_helpline__last_msg);
+		SLsmg_refresh();
+		backlog = 0;
+	}
+	mutex_unlock(&ui__lock);
+
+	return ret;
+}
+
+struct ui_helpline tui_helpline_fns = {
+	.pop	= tui_helpline__pop,
+	.push	= tui_helpline__push,
+	.show	= tui_helpline__show,
+};
+
+void ui_helpline__init(void)
+{
+	helpline_fns = &tui_helpline_fns;
+	ui_helpline__puts(" ");
+}
diff --git a/tools/perf/ui/tui/progress.c b/tools/perf/ui/tui/progress.c
new file mode 100644
index 000000000..71b6c8d94
--- /dev/null
+++ b/tools/perf/ui/tui/progress.c
@@ -0,0 +1,87 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/kernel.h>
+#include "../progress.h"
+#include "../libslang.h"
+#include "../ui.h"
+#include "tui.h"
+#include "units.h"
+#include "../browser.h"
+
+static void __tui_progress__init(struct ui_progress *p)
+{
+	p->next = p->step = p->total / (SLtt_Screen_Cols - 2) ?: 1;
+}
+
+static int get_title(struct ui_progress *p, char *buf, size_t size)
+{
+	char buf_cur[20];
+	char buf_tot[20];
+	int ret;
+
+	ret  = unit_number__scnprintf(buf_cur, sizeof(buf_cur), p->curr);
+	ret += unit_number__scnprintf(buf_tot, sizeof(buf_tot), p->total);
+
+	return ret + scnprintf(buf, size, "%s [%s/%s]",
+			       p->title, buf_cur, buf_tot);
+}
+
+static void tui_progress__update(struct ui_progress *p)
+{
+	char buf[100], *title = (char *) p->title;
+	int bar, y;
+	/*
+	 * FIXME: We should have a per UI backend way of showing progress,
+	 * stdio will just show a percentage as NN%, etc.
+	 */
+	if (use_browser <= 0)
+		return;
+
+	if (p->total == 0)
+		return;
+
+	if (p->size) {
+		get_title(p, buf, sizeof(buf));
+		title = buf;
+	}
+
+	ui__refresh_dimensions(false);
+	mutex_lock(&ui__lock);
+	y = SLtt_Screen_Rows / 2 - 2;
+	SLsmg_set_color(0);
+	SLsmg_draw_box(y, 0, 3, SLtt_Screen_Cols);
+	SLsmg_gotorc(y++, 1);
+	SLsmg_write_string(title);
+	SLsmg_fill_region(y, 1, 1, SLtt_Screen_Cols - 2, ' ');
+	SLsmg_set_color(HE_COLORSET_SELECTED);
+	bar = ((SLtt_Screen_Cols - 2) * p->curr) / p->total;
+	SLsmg_fill_region(y, 1, 1, bar, ' ');
+	SLsmg_refresh();
+	mutex_unlock(&ui__lock);
+}
+
+static void tui_progress__finish(void)
+{
+	int y;
+
+	if (use_browser <= 0)
+		return;
+
+	ui__refresh_dimensions(false);
+	mutex_lock(&ui__lock);
+	y = SLtt_Screen_Rows / 2 - 2;
+	SLsmg_set_color(0);
+	SLsmg_fill_region(y, 0, 3, SLtt_Screen_Cols, ' ');
+	SLsmg_refresh();
+	mutex_unlock(&ui__lock);
+}
+
+static struct ui_progress_ops tui_progress__ops = {
+	.init   = __tui_progress__init,
+	.update = tui_progress__update,
+	.finish = tui_progress__finish,
+};
+
+void tui_progress__init(void)
+{
+	ui_progress__ops = &tui_progress__ops;
+}
diff --git a/tools/perf/ui/tui/setup.c b/tools/perf/ui/tui/setup.c
new file mode 100644
index 000000000..022534eed
--- /dev/null
+++ b/tools/perf/ui/tui/setup.c
@@ -0,0 +1,201 @@
+#include <errno.h>
+#include <signal.h>
+#include <stdbool.h>
+#include <stdlib.h>
+#include <termios.h>
+#include <unistd.h>
+#include <linux/kernel.h>
+#ifdef HAVE_BACKTRACE_SUPPORT
+#include <execinfo.h>
+#endif
+
+#include "../../util/color.h"
+#include "../../util/debug.h"
+#include "../browser.h"
+#include "../helpline.h"
+#include "../ui.h"
+#include "../util.h"
+#include "../libslang.h"
+#include "../keysyms.h"
+#include "tui.h"
+
+static volatile int ui__need_resize;
+
+extern struct perf_error_ops perf_tui_eops;
+extern bool tui_helpline__set;
+
+extern void hist_browser__init_hpp(void);
+
+void ui__refresh_dimensions(bool force)
+{
+	if (force || ui__need_resize) {
+		ui__need_resize = 0;
+		mutex_lock(&ui__lock);
+		SLtt_get_screen_size();
+		SLsmg_reinit_smg();
+		mutex_unlock(&ui__lock);
+	}
+}
+
+static void ui__sigwinch(int sig __maybe_unused)
+{
+	ui__need_resize = 1;
+}
+
+static void ui__setup_sigwinch(void)
+{
+	static bool done;
+
+	if (done)
+		return;
+
+	done = true;
+	pthread__unblock_sigwinch();
+	signal(SIGWINCH, ui__sigwinch);
+}
+
+int ui__getch(int delay_secs)
+{
+	struct timeval timeout, *ptimeout = delay_secs ? &timeout : NULL;
+	fd_set read_set;
+	int err, key;
+
+	ui__setup_sigwinch();
+
+	FD_ZERO(&read_set);
+	FD_SET(0, &read_set);
+
+	if (delay_secs) {
+		timeout.tv_sec = delay_secs;
+		timeout.tv_usec = 0;
+	}
+
+        err = select(1, &read_set, NULL, NULL, ptimeout);
+
+	if (err == 0)
+		return K_TIMER;
+
+	if (err == -1) {
+		if (errno == EINTR)
+			return K_RESIZE;
+		return K_ERROR;
+	}
+
+	key = SLang_getkey();
+	if (key != K_ESC)
+		return key;
+
+	FD_ZERO(&read_set);
+	FD_SET(0, &read_set);
+	timeout.tv_sec = 0;
+	timeout.tv_usec = 20;
+        err = select(1, &read_set, NULL, NULL, &timeout);
+	if (err == 0)
+		return K_ESC;
+
+	SLang_ungetkey(key);
+	return SLkp_getkey();
+}
+
+#ifdef HAVE_BACKTRACE_SUPPORT
+static void ui__signal_backtrace(int sig)
+{
+	void *stackdump[32];
+	size_t size;
+
+	ui__exit(false);
+	psignal(sig, "perf");
+
+	printf("-------- backtrace --------\n");
+	size = backtrace(stackdump, ARRAY_SIZE(stackdump));
+	__dump_stack(stdout, stackdump, size);
+
+	exit(0);
+}
+#else
+# define ui__signal_backtrace  ui__signal
+#endif
+
+static void ui__signal(int sig)
+{
+	ui__exit(false);
+	psignal(sig, "perf");
+	exit(0);
+}
+
+static void ui__sigcont(int sig)
+{
+	static struct termios tty;
+
+	if (sig == SIGTSTP) {
+		while (tcgetattr(SLang_TT_Read_FD, &tty) == -1 && errno == EINTR)
+			;
+		while (write(SLang_TT_Read_FD, PERF_COLOR_RESET, sizeof(PERF_COLOR_RESET) - 1) == -1 && errno == EINTR)
+			;
+		raise(SIGSTOP);
+	} else {
+		while (tcsetattr(SLang_TT_Read_FD, TCSADRAIN, &tty) == -1 && errno == EINTR)
+			;
+		raise(SIGWINCH);
+	}
+}
+
+int ui__init(void)
+{
+	int err;
+
+	SLutf8_enable(-1);
+	SLtt_get_terminfo();
+	SLtt_get_screen_size();
+
+	err = SLsmg_init_smg();
+	if (err < 0)
+		goto out;
+	err = SLang_init_tty(-1, 0, 0);
+	if (err < 0)
+		goto out;
+	SLtty_set_suspend_state(true);
+
+	err = SLkp_init();
+	if (err < 0) {
+		pr_err("TUI initialization failed.\n");
+		goto out;
+	}
+
+	SLkp_define_keysym("^(kB)", SL_KEY_UNTAB);
+
+	signal(SIGSEGV, ui__signal_backtrace);
+	signal(SIGFPE, ui__signal_backtrace);
+	signal(SIGINT, ui__signal);
+	signal(SIGQUIT, ui__signal);
+	signal(SIGTERM, ui__signal);
+	signal(SIGTSTP, ui__sigcont);
+	signal(SIGCONT, ui__sigcont);
+
+	perf_error__register(&perf_tui_eops);
+
+	ui_helpline__init();
+	ui_browser__init();
+	tui_progress__init();
+
+	hist_browser__init_hpp();
+out:
+	return err;
+}
+
+void ui__exit(bool wait_for_ok)
+{
+	if (wait_for_ok && tui_helpline__set)
+		ui__question_window("Fatal Error",
+				    ui_helpline__last_msg,
+				    "Press any key...", 0);
+
+	SLtt_set_cursor_visibility(1);
+	if (mutex_trylock(&ui__lock)) {
+		SLsmg_refresh();
+		SLsmg_reset_smg();
+		mutex_unlock(&ui__lock);
+	}
+	SLang_reset_tty();
+	perf_error__unregister(&perf_tui_eops);
+}
diff --git a/tools/perf/ui/tui/tui.h b/tools/perf/ui/tui/tui.h
new file mode 100644
index 000000000..8de06f634
--- /dev/null
+++ b/tools/perf/ui/tui/tui.h
@@ -0,0 +1,7 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _PERF_TUI_H_
+#define _PERF_TUI_H_ 1
+
+void tui_progress__init(void);
+
+#endif /* _PERF_TUI_H_ */
diff --git a/tools/perf/ui/tui/util.c b/tools/perf/ui/tui/util.c
new file mode 100644
index 000000000..e4d322ce0
--- /dev/null
+++ b/tools/perf/ui/tui/util.c
@@ -0,0 +1,274 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <signal.h>
+#include <stdbool.h>
+#include <string.h>
+#include <stdlib.h>
+#include <sys/ttydefaults.h>
+
+#include "../browser.h"
+#include "../keysyms.h"
+#include "../helpline.h"
+#include "../ui.h"
+#include "../util.h"
+#include "../libslang.h"
+
+static void ui_browser__argv_write(struct ui_browser *browser,
+				   void *entry, int row)
+{
+	char **arg = entry;
+	bool current_entry = ui_browser__is_current_entry(browser, row);
+
+	ui_browser__set_color(browser, current_entry ? HE_COLORSET_SELECTED :
+						       HE_COLORSET_NORMAL);
+	ui_browser__write_nstring(browser, *arg, browser->width);
+}
+
+static int popup_menu__run(struct ui_browser *menu, int *keyp)
+{
+	int key;
+
+	if (ui_browser__show(menu, " ", "ESC: exit, ENTER|->: Select option") < 0)
+		return -1;
+
+	while (1) {
+		key = ui_browser__run(menu, 0);
+
+		switch (key) {
+		case K_RIGHT:
+		case K_ENTER:
+			key = menu->index;
+			break;
+		case K_LEFT:
+		case K_ESC:
+		case 'q':
+		case CTRL('c'):
+			key = -1;
+			break;
+		default:
+			if (keyp) {
+				*keyp = key;
+				key = menu->nr_entries;
+				break;
+			}
+			continue;
+		}
+
+		break;
+	}
+
+	ui_browser__hide(menu);
+	return key;
+}
+
+int ui__popup_menu(int argc, char * const argv[], int *keyp)
+{
+	struct ui_browser menu = {
+		.entries    = (void *)argv,
+		.refresh    = ui_browser__argv_refresh,
+		.seek	    = ui_browser__argv_seek,
+		.write	    = ui_browser__argv_write,
+		.nr_entries = argc,
+	};
+	return popup_menu__run(&menu, keyp);
+}
+
+int ui_browser__input_window(const char *title, const char *text, char *input,
+			     const char *exit_msg, int delay_secs)
+{
+	int x, y, len, key;
+	int max_len = 60, nr_lines = 0;
+	static char buf[50];
+	const char *t;
+
+	t = text;
+	while (1) {
+		const char *sep = strchr(t, '\n');
+
+		if (sep == NULL)
+			sep = strchr(t, '\0');
+		len = sep - t;
+		if (max_len < len)
+			max_len = len;
+		++nr_lines;
+		if (*sep == '\0')
+			break;
+		t = sep + 1;
+	}
+
+	mutex_lock(&ui__lock);
+
+	max_len += 2;
+	nr_lines += 8;
+	y = SLtt_Screen_Rows / 2 - nr_lines / 2;
+	x = SLtt_Screen_Cols / 2 - max_len / 2;
+
+	SLsmg_set_color(0);
+	SLsmg_draw_box(y, x++, nr_lines, max_len);
+	if (title) {
+		SLsmg_gotorc(y, x + 1);
+		SLsmg_write_string(title);
+	}
+	SLsmg_gotorc(++y, x);
+	nr_lines -= 7;
+	max_len -= 2;
+	SLsmg_write_wrapped_string((unsigned char *)text, y, x,
+				   nr_lines, max_len, 1);
+	y += nr_lines;
+	len = 5;
+	while (len--) {
+		SLsmg_gotorc(y + len - 1, x);
+		SLsmg_write_nstring(" ", max_len);
+	}
+	SLsmg_draw_box(y++, x + 1, 3, max_len - 2);
+
+	SLsmg_gotorc(y + 3, x);
+	SLsmg_write_nstring(exit_msg, max_len);
+	SLsmg_refresh();
+
+	mutex_unlock(&ui__lock);
+
+	x += 2;
+	len = 0;
+	key = ui__getch(delay_secs);
+	while (key != K_TIMER && key != K_ENTER && key != K_ESC) {
+		mutex_lock(&ui__lock);
+
+		if (key == K_BKSPC) {
+			if (len == 0) {
+				mutex_unlock(&ui__lock);
+				goto next_key;
+			}
+			SLsmg_gotorc(y, x + --len);
+			SLsmg_write_char(' ');
+		} else {
+			buf[len] = key;
+			SLsmg_gotorc(y, x + len++);
+			SLsmg_write_char(key);
+		}
+		SLsmg_refresh();
+
+		mutex_unlock(&ui__lock);
+
+		/* XXX more graceful overflow handling needed */
+		if (len == sizeof(buf) - 1) {
+			ui_helpline__push("maximum size of symbol name reached!");
+			key = K_ENTER;
+			break;
+		}
+next_key:
+		key = ui__getch(delay_secs);
+	}
+
+	buf[len] = '\0';
+	strncpy(input, buf, len+1);
+	return key;
+}
+
+void __ui__info_window(const char *title, const char *text, const char *exit_msg)
+{
+	int x, y;
+	int max_len = 0, nr_lines = 0;
+	const char *t;
+
+	t = text;
+	while (1) {
+		const char *sep = strchr(t, '\n');
+		int len;
+
+		if (sep == NULL)
+			sep = strchr(t, '\0');
+		len = sep - t;
+		if (max_len < len)
+			max_len = len;
+		++nr_lines;
+		if (*sep == '\0')
+			break;
+		t = sep + 1;
+	}
+
+	max_len += 2;
+	nr_lines += 2;
+	if (exit_msg)
+		nr_lines += 2;
+	y = SLtt_Screen_Rows / 2 - nr_lines / 2,
+	x = SLtt_Screen_Cols / 2 - max_len / 2;
+
+	SLsmg_set_color(0);
+	SLsmg_draw_box(y, x++, nr_lines, max_len);
+	if (title) {
+		SLsmg_gotorc(y, x + 1);
+		SLsmg_write_string(title);
+	}
+	SLsmg_gotorc(++y, x);
+	if (exit_msg)
+		nr_lines -= 2;
+	max_len -= 2;
+	SLsmg_write_wrapped_string((unsigned char *)text, y, x,
+				   nr_lines, max_len, 1);
+	if (exit_msg) {
+		SLsmg_gotorc(y + nr_lines - 2, x);
+		SLsmg_write_nstring(" ", max_len);
+		SLsmg_gotorc(y + nr_lines - 1, x);
+		SLsmg_write_nstring(exit_msg, max_len);
+	}
+}
+
+void ui__info_window(const char *title, const char *text)
+{
+	mutex_lock(&ui__lock);
+	__ui__info_window(title, text, NULL);
+	SLsmg_refresh();
+	mutex_unlock(&ui__lock);
+}
+
+int ui__question_window(const char *title, const char *text,
+			const char *exit_msg, int delay_secs)
+{
+	mutex_lock(&ui__lock);
+	__ui__info_window(title, text, exit_msg);
+	SLsmg_refresh();
+	mutex_unlock(&ui__lock);
+	return ui__getch(delay_secs);
+}
+
+int ui__help_window(const char *text)
+{
+	return ui__question_window("Help", text, "Press any key...", 0);
+}
+
+int ui__dialog_yesno(const char *msg)
+{
+	return ui__question_window(NULL, msg, "Enter: Yes, ESC: No", 0);
+}
+
+static int __ui__warning(const char *title, const char *format, va_list args)
+{
+	char *s;
+
+	if (vasprintf(&s, format, args) > 0) {
+		int key;
+
+		key = ui__question_window(title, s, "Press any key...", 0);
+		free(s);
+		return key;
+	}
+
+	fprintf(stderr, "%s\n", title);
+	vfprintf(stderr, format, args);
+	return K_ESC;
+}
+
+static int perf_tui__error(const char *format, va_list args)
+{
+	return __ui__warning("Error:", format, args);
+}
+
+static int perf_tui__warning(const char *format, va_list args)
+{
+	return __ui__warning("Warning:", format, args);
+}
+
+struct perf_error_ops perf_tui_eops = {
+	.error		= perf_tui__error,
+	.warning	= perf_tui__warning,
+};