[PATCH 4.14 101/218] perf jevents: Fix event syntax error caused by ExtSel

From: Greg Kroah-Hartman
Date: Mon Jun 13 2022 - 06:55:16 EST

From: Zhengjun Xing <zhengjun.xing@xxxxxxxxxxxxxxx>

[ Upstream commit f4df0dbbe62ee8e4405a57b27ccd54393971c773 ]

In the origin code, when "ExtSel" is 1, the eventcode will change to
"eventcode |= 1 << 21”. For event “UNC_Q_RxL_CREDITS_CONSUMED_VN0.DRS",
its "ExtSel" is "1", its eventcode will change from 0x1E to 0x20001E,
but in fact the eventcode should <=0x1FF, so this will cause the parse

# perf stat -e "UNC_Q_RxL_CREDITS_CONSUMED_VN0.DRS" -a sleep 0.1
event syntax error: '.._RxL_CREDITS_CONSUMED_VN0.DRS'
\___ value too big for format, maximum is 511

On the perf kernel side, the kernel assumes the valid bits are continuous.
It will adjust the 0x100 (bit 8 for perf tool) to bit 21 in HW.

DEFINE_UNCORE_FORMAT_ATTR(event_ext, event, "config:0-7,21");

So the perf tool follows the kernel side and just set bit8 other than bit21.

Fixes: fedb2b518239cbc0 ("perf jevents: Add support for parsing uncore json files")
Reviewed-by: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>
Signed-off-by: Xing Zhengjun <zhengjun.xing@xxxxxxxxxxxxxxx>
Acked-by: Ian Rogers <irogers@xxxxxxxxxx>
Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxx>
Cc: Andi Kleen <ak@xxxxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20220525140410.1706851-1-zhengjun.xing@xxxxxxxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
tools/perf/pmu-events/jevents.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/pmu-events/jevents.c b/tools/perf/pmu-events/jevents.c
index 8e487b2a37a6..dcfbbade657e 100644
--- a/tools/perf/pmu-events/jevents.c
+++ b/tools/perf/pmu-events/jevents.c
@@ -428,7 +428,7 @@ int json_events(const char *fn,
} else if (json_streq(map, field, "ExtSel")) {
char *code = NULL;
addfield(map, &code, "", "", val);
- eventcode |= strtoul(code, NULL, 0) << 21;
+ eventcode |= strtoul(code, NULL, 0) << 8;
} else if (json_streq(map, field, "EventName")) {
addfield(map, &name, "", "", val);