[PATCH v6 4/8] perf cs-etm: Add exception number in exception packet

[Leo Yan]

When an exception packet comes, it contains the information for
exception number; the exception number indicates the exception types,
so from it we can know if the exception is taken for interrupt,
system call or other traps, etc.

This patch simply adds a field in cs_etm_packet struct, it records
exception number for exception packet that will then be used to
properly identify exception types to the perf synthesize mechanic.

Signed-off-by: Leo Yan <leo....@linaro.org>
---
 .../perf/util/cs-etm-decoder/cs-etm-decoder.c | 20 +++++++++++++++----
 .../perf/util/cs-etm-decoder/cs-etm-decoder.h |  1 +
 2 files changed, 17 insertions(+), 4 deletions(-)

diff --git a/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c 
b/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c
index e98ee49a1527..294efa76c9e3 100644
--- a/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c
+++ b/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c
@@ -294,6 +294,7 @@ static void cs_etm_decoder__clear_buffer(struct 
cs_etm_decoder *decoder)
                decoder->packet_buffer[i].last_instr_subtype = 0;
                decoder->packet_buffer[i].last_instr_cond = 0;
                decoder->packet_buffer[i].flags = 0;
+               decoder->packet_buffer[i].exception_number = UINT32_MAX;
                decoder->packet_buffer[i].cpu = INT_MIN;
        }
 }
@@ -331,6 +332,7 @@ cs_etm_decoder__buffer_packet(struct cs_etm_decoder 
*decoder,
        decoder->packet_buffer[et].last_instr_subtype = 0;
        decoder->packet_buffer[et].last_instr_cond = 0;
        decoder->packet_buffer[et].flags = 0;
+       decoder->packet_buffer[et].exception_number = UINT32_MAX;
 
        if (decoder->packet_count == MAX_BUFFER - 1)
                return OCSD_RESP_WAIT;
@@ -406,10 +408,20 @@ cs_etm_decoder__buffer_discontinuity(struct 
cs_etm_decoder *decoder,
 
 static ocsd_datapath_resp_t
 cs_etm_decoder__buffer_exception(struct cs_etm_decoder *decoder,
+                                const ocsd_generic_trace_elem *elem,
                                 const uint8_t trace_chan_id)
-{
-       return cs_etm_decoder__buffer_packet(decoder, trace_chan_id,
-                                            CS_ETM_EXCEPTION);
+{      int ret = 0;
+       struct cs_etm_packet *packet;
+
+       ret = cs_etm_decoder__buffer_packet(decoder, trace_chan_id,
+                                           CS_ETM_EXCEPTION);
+       if (ret != OCSD_RESP_CONT && ret != OCSD_RESP_WAIT)
+               return ret;
+
+       packet = &decoder->packet_buffer[decoder->tail];
+       packet->exception_number = elem->exception_number;
+
+       return ret;
 }
 
 static ocsd_datapath_resp_t
@@ -443,7 +455,7 @@ static ocsd_datapath_resp_t 
cs_etm_decoder__gen_trace_elem_printer(
                                                    trace_chan_id);
                break;
        case OCSD_GEN_TRC_ELEM_EXCEPTION:
-               resp = cs_etm_decoder__buffer_exception(decoder,
+               resp = cs_etm_decoder__buffer_exception(decoder, elem,
                                                        trace_chan_id);
                break;
        case OCSD_GEN_TRC_ELEM_EXCEPTION_RET:
diff --git a/tools/perf/util/cs-etm-decoder/cs-etm-decoder.h 
b/tools/perf/util/cs-etm-decoder/cs-etm-decoder.h
index 23600e57a215..012b4728a46f 100644
--- a/tools/perf/util/cs-etm-decoder/cs-etm-decoder.h
+++ b/tools/perf/util/cs-etm-decoder/cs-etm-decoder.h
@@ -46,6 +46,7 @@ struct cs_etm_packet {
        u32 last_instr_type;
        u32 last_instr_subtype;
        u32 flags;
+       u32 exception_number;
        u8 last_instr_cond;
        u8 last_instr_taken_branch;
        u8 last_instr_size;
-- 
2.17.1