Commit a3f895be authored by Arnaldo Carvalho de Melo's avatar Arnaldo Carvalho de Melo
Browse files

perf annotate browser: Initial loop detection 



Simple algorithm, just look for the next backward jump that points to
before the cursor.

Then draw an arrow connecting the jump to its target.

Do this as you move the cursor, entering/exiting possible loops.

Ex (graph chars replaced to avoid mail encoding woes):

avc_has_perm_flags
    0.00 |         nopl   0x0(%rax)
    5.36 |+-> 68:  mov    (%rax),%rax
    5.15 ||        test   %rax,%rax
    0.00 ||      v je     130
    2.96 ||   74:  cmp    -0x20(%rax),%ebx
   47.38 ||        lea    -0x20(%rax),%rcx
    0.28 ||      ^ jne    68
    3.16 ||        cmp    -0x18(%rax),%dx
    0.00 |+------^ jne    68
    4.92 |         cmp    0x4(%rcx),%r13d
    0.00 |       v jne    68
    1.15 |         test   %rcx,%rcx
    0.00 |       v je     130

Suggested-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-5gairf6or7dazlx3ocxwvftm@git.kernel.org


Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent 59d038d5

tools/perf/ui/browser.c

+39 −0
Original line number Diff line number Diff line
@@ -600,6 +600,45 @@ void ui_browser__write_graph(struct ui_browser *browser __used, int graph) 
	SLsmg_set_char_set(0);

}



void __ui_browser__line_arrow_up(struct ui_browser *browser, unsigned int column,

				 u64 start, u64 end, int start_width)

{

	unsigned int row, end_row;



	SLsmg_set_char_set(1);



	if (start < browser->top_idx + browser->height) {

		row = start - browser->top_idx;

		ui_browser__gotorc(browser, row, column);

		SLsmg_write_char(SLSMG_LLCORN_CHAR);

		ui_browser__gotorc(browser, row, column + 1);

		SLsmg_draw_hline(start_width);



		if (row-- == 0)

			goto out;

	} else

		row = browser->height - 1;



	if (end > browser->top_idx)

		end_row = end - browser->top_idx;

	else

		end_row = 0;



	ui_browser__gotorc(browser, end_row, column);

	SLsmg_draw_vline(row - end_row + 1);



	ui_browser__gotorc(browser, end_row, column);

	if (end >= browser->top_idx) {

		SLsmg_write_char(SLSMG_ULCORN_CHAR);

		ui_browser__gotorc(browser, end_row, column + 1);

		SLsmg_write_char(SLSMG_HLINE_CHAR);

		ui_browser__gotorc(browser, end_row, column + 2);

		SLsmg_write_char(SLSMG_RARROW_CHAR);

	}

out:

	SLsmg_set_char_set(0);

}



void ui_browser__init(void)

{

	int i = 0;

tools/perf/ui/browser.h

+2 −0
Original line number Diff line number Diff line
@@ -38,6 +38,8 @@ void ui_browser__reset_index(struct ui_browser *self); 


void ui_browser__gotorc(struct ui_browser *self, int y, int x);

void ui_browser__write_graph(struct ui_browser *browser, int graph);

void __ui_browser__line_arrow_up(struct ui_browser *browser, unsigned int column,

				 u64 start, u64 end, int start_width);

void __ui_browser__show_title(struct ui_browser *browser, const char *title);

void ui_browser__show_title(struct ui_browser *browser, const char *title);

int ui_browser__show(struct ui_browser *self, const char *title,

tools/perf/ui/browsers/annotate.c

+57 −4
Original line number Diff line number Diff line
@@ -141,6 +141,59 @@ static void annotate_browser__write(struct ui_browser *self, void *entry, int ro 
		ab->selection = dl;

}



static void annotate_browser__draw_current_loop(struct ui_browser *browser)

{

	struct annotate_browser *ab = container_of(browser, struct annotate_browser, b);

	struct map_symbol *ms = browser->priv;

	struct symbol *sym = ms->sym;

	struct annotation *notes = symbol__annotation(sym);

	struct disasm_line *cursor = ab->selection, *pos = cursor, *target;

	struct browser_disasm_line *bcursor = disasm_line__browser(cursor),

				   *btarget, *bpos;

	unsigned int from, to, start_width = 2;



	list_for_each_entry_from(pos, &notes->src->source, node) {

		if (!pos->ins || !ins__is_jump(pos->ins))

			continue;



		target = ab->offsets[pos->ops.target];

		if (!target)

			continue;



		btarget = disasm_line__browser(target);

		if (btarget->idx <= bcursor->idx)

			goto found;

	}



	return;



found:

	bpos = disasm_line__browser(pos);

	if (ab->hide_src_code) {

		from = bpos->idx_asm;

		to = btarget->idx_asm;

	} else {

		from = (u64)bpos->idx;

		to = (u64)btarget->idx;

	}



	ui_browser__set_color(browser, HE_COLORSET_CODE);



	if (!bpos->jump_target)

		start_width += ab->offset_width + 1;



	__ui_browser__line_arrow_up(browser, 10, from, to, start_width);

}



static unsigned int annotate_browser__refresh(struct ui_browser *browser)

{

	int ret = ui_browser__list_head_refresh(browser);



	annotate_browser__draw_current_loop(browser);



	return ret;

}



static double disasm_line__calc_percent(struct disasm_line *dl, struct symbol *sym, int evidx)

{

	double percent = 0.0;
@@ -666,7 +719,7 @@ int symbol__tui_annotate(struct symbol *sym, struct map *map, int evidx, 
	};

	struct annotate_browser browser = {

		.b = {

			.refresh = ui_browser__list_head_refresh,

			.refresh = annotate_browser__refresh,

			.seek	 = ui_browser__list_head_seek,

			.write	 = annotate_browser__write,

			.filter  = disasm_line__filter,

CRA Git | Maintained and supported by SUSTech CRA and CCSE