[PATCH 4.9 09/25] perf intel-pt: Use __fallthrough

[Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>

commit 7ea6856d6f5629d742edc23b8b76e6263371ef45 upstream.

To address new warnings emmited by gcc 7, e.g.::

    CC       /tmp/build/perf/util/intel-pt-decoder/intel-pt-pkt-decoder.o
    CC       /tmp/build/perf/tests/parse-events.o
  util/intel-pt-decoder/intel-pt-pkt-decoder.c: In function 'intel_pt_pkt_desc':
  util/intel-pt-decoder/intel-pt-pkt-decoder.c:499:6: error: this statement may fall through [-Werror=implicit-fallthrough=]
     if (!(packet->count))
        ^
  util/intel-pt-decoder/intel-pt-pkt-decoder.c:501:2: note: here
    case INTEL_PT_CYC:
    ^~~~
    CC       /tmp/build/perf/util/intel-pt-decoder/intel-pt-decoder.o
  cc1: all warnings being treated as errors

Acked-by: Andi Kleen <ak@xxxxxxxxxxxxxxx>
Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Cc: David Ahern <dsahern@xxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Wang Nan <wangnan0@xxxxxxxxxx>
Link: http://lkml.kernel.org/n/tip-mf0hw789pu9x855us5l32c83@xxxxxxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 tools/perf/util/intel-pt-decoder/intel-pt-decoder.c     |    5 +++++
 tools/perf/util/intel-pt-decoder/intel-pt-pkt-decoder.c |    2 ++
 2 files changed, 7 insertions(+)

--- a/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c
+++ b/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c
@@ -22,6 +22,7 @@
 #include <errno.h>
 #include <stdint.h>
 #include <inttypes.h>
+#include <linux/compiler.h>
 
 #include "../cache.h"
 #include "../util.h"
@@ -1744,6 +1745,7 @@ static int intel_pt_walk_psb(struct inte
 		switch (decoder->packet.type) {
 		case INTEL_PT_TIP_PGD:
 			decoder->continuous_period = false;
+			__fallthrough;
 		case INTEL_PT_TIP_PGE:
 		case INTEL_PT_TIP:
 			intel_pt_log("ERROR: Unexpected packet\n");
@@ -1797,6 +1799,8 @@ static int intel_pt_walk_psb(struct inte
 			decoder->pge = false;
 			decoder->continuous_period = false;
 			intel_pt_clear_tx_flags(decoder);
+			__fallthrough;
+
 		case INTEL_PT_TNT:
 			decoder->have_tma = false;
 			intel_pt_log("ERROR: Unexpected packet\n");
@@ -1837,6 +1841,7 @@ static int intel_pt_walk_to_ip(struct in
 		switch (decoder->packet.type) {
 		case INTEL_PT_TIP_PGD:
 			decoder->continuous_period = false;
+			__fallthrough;
 		case INTEL_PT_TIP_PGE:
 		case INTEL_PT_TIP:
 			decoder->pge = decoder->packet.type != INTEL_PT_TIP_PGD;
--- a/tools/perf/util/intel-pt-decoder/intel-pt-pkt-decoder.c
+++ b/tools/perf/util/intel-pt-decoder/intel-pt-pkt-decoder.c
@@ -17,6 +17,7 @@
 #include <string.h>
 #include <endian.h>
 #include <byteswap.h>
+#include <linux/compiler.h>
 
 #include "intel-pt-pkt-decoder.h"
 
@@ -498,6 +499,7 @@ int intel_pt_pkt_desc(const struct intel
 	case INTEL_PT_FUP:
 		if (!(packet->count))
 			return snprintf(buf, buf_len, "%s no ip", name);
+		__fallthrough;
 	case INTEL_PT_CYC:
 	case INTEL_PT_VMCS:
 	case INTEL_PT_MTC: