perf c2c: Use stdio interface if slang is not supported

[ Upstream commit c404021 ]

If the slang lib is not installed on the system, perf c2c tool disables TUI
mode and roll back to use stdio mode;  but the flag 'c2c.use_stdio' is
missed to set true and thus it wrongly applies UI quirks in the function
ui_quirks().

This commit forces to use stdio interface if slang is not supported, and
it can avoid to apply the UI quirks and show the correct metric header.

Before:

=================================================
      Shared Cache Line Distribution Pareto
=================================================
  -------------------------------------------------------------------------------
      0        0        0       99        0        0        0      0xaaaac17d6000
  -------------------------------------------------------------------------------
    0.00%    0.00%    6.06%    0.00%    0.00%    0.00%   0x20   N/A       0      0xaaaac17c25ac         0         0        43       375    18469         2  [.] 0x00000000000025ac  memstress         memstress[25ac]   0
    0.00%    0.00%   93.94%    0.00%    0.00%    0.00%   0x29   N/A       0      0xaaaac17c3e88         0         0       173       180      135         2  [.] 0x0000000000003e88  memstress         memstress[3e88]   0

After:

=================================================
      Shared Cache Line Distribution Pareto
=================================================
  -------------------------------------------------------------------------------
      0        0        0       99        0        0        0      0xaaaac17d6000
  -------------------------------------------------------------------------------
           0.00%    0.00%    6.06%    0.00%    0.00%    0.00%                0x20   N/A       0      0xaaaac17c25ac         0         0        43       375    18469         2  [.] 0x00000000000025ac  memstress         memstress[25ac]   0
           0.00%    0.00%   93.94%    0.00%    0.00%    0.00%                0x29   N/A       0      0xaaaac17c3e88         0         0       173       180      135         2  [.] 0x0000000000003e88  memstress         memstress[3e88]   0

Fixes: 5a1a99c ("perf c2c report: Add main TUI browser")
Reported-by: Joe Mario <jmario@redhat.com>
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20220526145400.611249-1-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

tools/perf/builtin-c2c.c

@@ -2694,9 +2694,7 @@ static int perf_c2c__report(int argc, const char **argv)
 		   "the input file to process"),
 	OPT_INCR('N', "node-info", &c2c.node_info,
 		 "show extra node info in report (repeat for more info)"),
-#ifdef HAVE_SLANG_SUPPORT
 	OPT_BOOLEAN(0, "stdio", &c2c.use_stdio, "Use the stdio interface"),
-#endif
 	OPT_BOOLEAN(0, "stats", &c2c.stats_only,
 		    "Display only statistic tables (implies --stdio)"),
 	OPT_BOOLEAN(0, "full-symbols", &c2c.symbol_full,
@@ -2725,6 +2723,10 @@ static int perf_c2c__report(int argc, const char **argv)
 	if (argc)
 		usage_with_options(report_c2c_usage, options);
 
+#ifndef HAVE_SLANG_SUPPORT
+	c2c.use_stdio = true;
+#endif
+
 	if (c2c.stats_only)
 		c2c.use_stdio = true;