[PATCH 05/25] perf intel-pt: Add decoder support for PEBS via PT

Arnaldo Carvalho de Melo
2019-06-21T17:39:41Z

From: Adrian Hunter <adrian.hunter@intel.com>

PEBS data is encoded in Block Item Packets (BIP). Populate a new structure
intel_pt_blk_items with the values and, upon a Block End Packet (BEP),
report them as a new Intel PT sample type INTEL_PT_BLK_ITEMS.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/20190610072803.10456-4-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
.../util/intel-pt-decoder/intel-pt-decoder.c | 78 +++++++++-
.../util/intel-pt-decoder/intel-pt-decoder.h | 137 ++++++++++++++++++
2 files changed, 214 insertions(+), 1 deletion(-)

diff --git a/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c b/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c
index 2f7791d4034f..f8b71bf2bb4c 100644
--- a/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c
+++ b/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c
@@ -134,6 +134,9 @@ struct intel_pt_decoder {
struct intel_pt_stack stack;
enum intel_pt_pkt_state pkt_state;
enum intel_pt_pkt_ctx pkt_ctx;
+ enum intel_pt_pkt_ctx prev_pkt_ctx;
+ enum intel_pt_blk_type blk_type;
+ int blk_type_pos;
struct intel_pt_pkt packet;
struct intel_pt_pkt tnt;
int pkt_step;
@@ -167,6 +170,7 @@ struct intel_pt_decoder {
bool set_fup_mwait;
bool set_fup_pwre;
bool set_fup_exstop;
+ bool set_fup_bep;
bool sample_cyc;
unsigned int fup_tx_flags;
unsigned int tx_flags;
@@ -560,6 +564,7 @@ static int intel_pt_get_split_packet(struct intel_pt_decoder *decoder)
memcpy(buf + len, decoder->buf, n);
len += n;

+ decoder->prev_pkt_ctx = decoder->pkt_ctx;
ret = intel_pt_get_packet(buf, len, &decoder->packet, &decoder->pkt_ctx);
if (ret < (int)old_len) {
decoder->next_buf = decoder->buf;
@@ -885,6 +890,7 @@ static int intel_pt_get_next_packet(struct intel_pt_decoder *decoder)
return ret;
}

+ decoder->prev_pkt_ctx = decoder->pkt_ctx;
ret = intel_pt_get_packet(decoder->buf, decoder->len,
&decoder->packet, &decoder->pkt_ctx);
if (ret == INTEL_PT_NEED_MORE_BYTES && BITS_PER_LONG == 32 &&
@@ -1124,6 +1130,14 @@ static bool intel_pt_fup_event(struct intel_pt_decoder *decoder)
decoder->state.to_ip = 0;
ret = true;
}
+ if (decoder->set_fup_bep) {
+ decoder->set_fup_bep = false;
+ decoder->state.type |= INTEL_PT_BLK_ITEMS;
+ decoder->state.type &= ~INTEL_PT_BRANCH;
+ decoder->state.from_ip = decoder->ip;
+ decoder->state.to_ip = 0;
+ ret = true;
+ }
return ret;
}

@@ -1609,6 +1623,46 @@ static void intel_pt_calc_cyc_timestamp(struct intel_pt_decoder *decoder)
intel_pt_log_to("Setting timestamp", decoder->timestamp);
}

+static void intel_pt_bbp(struct intel_pt_decoder *decoder)
+{
+ if (decoder->prev_pkt_ctx == INTEL_PT_NO_CTX) {
+ memset(decoder->state.items.mask, 0, sizeof(decoder->state.items.mask));
+ decoder->state.items.is_32_bit = false;
+ }
+ decoder->blk_type = decoder->packet.payload;
+ decoder->blk_type_pos = intel_pt_blk_type_pos(decoder->blk_type);
+ if (decoder->blk_type == INTEL_PT_GP_REGS)
+ decoder->state.items.is_32_bit = decoder->packet.count;
+ if (decoder->blk_type_pos < 0) {
+ intel_pt_log("WARNING: Unknown block type %u\n",
+ decoder->blk_type);
+ } else if (decoder->state.items.mask[decoder->blk_type_pos]) {
+ intel_pt_log("WARNING: Duplicate block type %u\n",
+ decoder->blk_type);
+ }
+}
+
+static void intel_pt_bip(struct intel_pt_decoder *decoder)
+{
+ uint32_t id = decoder->packet.count;
+ uint32_t bit = 1 << id;
+ int pos = decoder->blk_type_pos;
+
+ if (pos < 0 || id >= INTEL_PT_BLK_ITEM_ID_CNT) {
+ intel_pt_log("WARNING: Unknown block item %u type %d\n",
+ id, decoder->blk_type);
+ return;
+ }
+
+ if (decoder->state.items.mask[pos] & bit) {
+ intel_pt_log("WARNING: Duplicate block item %u type %d\n",
+ id, decoder->blk_type);
+ }
+
+ decoder->state.items.mask[pos] |= bit;
+ decoder->state.items.val[pos][id] = decoder->packet.payload;
+}
+
/* Walk PSB+ packets when already in sync. */
static int intel_pt_walk_psbend(struct intel_pt_decoder *decoder)
{
@@ -2063,10 +2117,31 @@ static int intel_pt_walk_trace(struct intel_pt_decoder *decoder)
return 0;

case INTEL_PT_BBP:
+ intel_pt_bbp(decoder);
+ break;
+
case INTEL_PT_BIP:
+ intel_pt_bip(decoder);
+ break;
+
case INTEL_PT_BEP:
+ decoder->state.type = INTEL_PT_BLK_ITEMS;
+ decoder->state.from_ip = decoder->ip;
+ decoder->state.to_ip = 0;
+ return 0;
+
case INTEL_PT_BEP_IP:
- break;
+ err = intel_pt_get_next_packet(decoder);
+ if (err)
+ return err;
+ if (decoder->packet.type == INTEL_PT_FUP) {
+ decoder->set_fup_bep = true;
+ no_tip = true;
+ } else {
+ intel_pt_log_at("ERROR: Missing FUP after BEP",
+ decoder->pos);
+ }
+ goto next;

default:
return intel_pt_bug(decoder);
@@ -2335,6 +2410,7 @@ static int intel_pt_sync_ip(struct intel_pt_decoder *decoder)
decoder->set_fup_mwait = false;
decoder->set_fup_pwre = false;
decoder->set_fup_exstop = false;
+ decoder->set_fup_bep = false;

if (!decoder->branch_enable) {
decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
diff --git a/tools/perf/util/intel-pt-decoder/intel-pt-decoder.h b/tools/perf/util/intel-pt-decoder/intel-pt-decoder.h
index 754efa8b501f..9957f2ccdca8 100644
--- a/tools/perf/util/intel-pt-decoder/intel-pt-decoder.h
+++ b/tools/perf/util/intel-pt-decoder/intel-pt-decoder.h
@@ -30,6 +30,7 @@ enum intel_pt_sample_type {
INTEL_PT_CBR_CHG = 1 << 8,
INTEL_PT_TRACE_BEGIN = 1 << 9,
INTEL_PT_TRACE_END = 1 << 10,
+ INTEL_PT_BLK_ITEMS = 1 << 11,
};

enum intel_pt_period_type {
@@ -61,6 +62,141 @@ enum intel_pt_param_flags {
INTEL_PT_FUP_WITH_NLIP = 1 << 0,
};

+enum intel_pt_blk_type {
+ INTEL_PT_GP_REGS = 1,
+ INTEL_PT_PEBS_BASIC = 4,
+ INTEL_PT_PEBS_MEM = 5,
+ INTEL_PT_LBR_0 = 8,
+ INTEL_PT_LBR_1 = 9,
+ INTEL_PT_LBR_2 = 10,
+ INTEL_PT_XMM = 16,
+ INTEL_PT_BLK_TYPE_MAX
+};
+
+/*
+ * The block type numbers are not sequential but here they are given sequential
+ * positions to avoid wasting space for array placement.
+ */
+enum intel_pt_blk_type_pos {
+ INTEL_PT_GP_REGS_POS,
+ INTEL_PT_PEBS_BASIC_POS,
+ INTEL_PT_PEBS_MEM_POS,
+ INTEL_PT_LBR_0_POS,
+ INTEL_PT_LBR_1_POS,
+ INTEL_PT_LBR_2_POS,
+ INTEL_PT_XMM_POS,
+ INTEL_PT_BLK_TYPE_CNT
+};
+
+/* Get the array position for a block type */
+static inline int intel_pt_blk_type_pos(enum intel_pt_blk_type blk_type)
+{
+#define BLK_TYPE(bt) [INTEL_PT_##bt] = INTEL_PT_##bt##_POS + 1
+ const int map[INTEL_PT_BLK_TYPE_MAX] = {
+ BLK_TYPE(GP_REGS),
+ BLK_TYPE(PEBS_BASIC),
+ BLK_TYPE(PEBS_MEM),
+ BLK_TYPE(LBR_0),
+ BLK_TYPE(LBR_1),
+ BLK_TYPE(LBR_2),
+ BLK_TYPE(XMM),
+ };
+#undef BLK_TYPE
+
+ return blk_type < INTEL_PT_BLK_TYPE_MAX ? map[blk_type] - 1 : -1;
+}
+
+#define INTEL_PT_BLK_ITEM_ID_CNT 32
+
+/*
+ * Use unions so that the block items can be accessed by name or by array index.
+ * There is an array of 32-bit masks for each block type, which indicate which
+ * values are present. Then arrays of 32 64-bit values for each block type.
+ */
+struct intel_pt_blk_items {
+ union {
+ uint32_t mask[INTEL_PT_BLK_TYPE_CNT];
+ struct {
+ uint32_t has_rflags:1;
+ uint32_t has_rip:1;
+ uint32_t has_rax:1;
+ uint32_t has_rcx:1;
+ uint32_t has_rdx:1;
+ uint32_t has_rbx:1;
+ uint32_t has_rsp:1;
+ uint32_t has_rbp:1;
+ uint32_t has_rsi:1;
+ uint32_t has_rdi:1;
+ uint32_t has_r8:1;
+ uint32_t has_r9:1;
+ uint32_t has_r10:1;
+ uint32_t has_r11:1;
+ uint32_t has_r12:1;
+ uint32_t has_r13:1;
+ uint32_t has_r14:1;
+ uint32_t has_r15:1;
+ uint32_t has_unused_0:14;
+ uint32_t has_ip:1;
+ uint32_t has_applicable_counters:1;
+ uint32_t has_timestamp:1;
+ uint32_t has_unused_1:29;
+ uint32_t has_mem_access_address:1;
+ uint32_t has_mem_aux_info:1;
+ uint32_t has_mem_access_latency:1;
+ uint32_t has_tsx_aux_info:1;
+ uint32_t has_unused_2:28;
+ uint32_t has_lbr_0;
+ uint32_t has_lbr_1;
+ uint32_t has_lbr_2;
+ uint32_t has_xmm;
+ };
+ };
+ union {
+ uint64_t val[INTEL_PT_BLK_TYPE_CNT][INTEL_PT_BLK_ITEM_ID_CNT];
+ struct {
+ struct {
+ uint64_t rflags;
+ uint64_t rip;
+ uint64_t rax;
+ uint64_t rcx;
+ uint64_t rdx;
+ uint64_t rbx;
+ uint64_t rsp;
+ uint64_t rbp;
+ uint64_t rsi;
+ uint64_t rdi;
+ uint64_t r8;
+ uint64_t r9;
+ uint64_t r10;
+ uint64_t r11;
+ uint64_t r12;
+ uint64_t r13;
+ uint64_t r14;
+ uint64_t r15;
+ uint64_t unused_0[INTEL_PT_BLK_ITEM_ID_CNT - 18];
+ };
+ struct {
+ uint64_t ip;
+ uint64_t applicable_counters;
+ uint64_t timestamp;
+ uint64_t unused_1[INTEL_PT_BLK_ITEM_ID_CNT - 3];
+ };
+ struct {
+ uint64_t mem_access_address;
+ uint64_t mem_aux_info;
+ uint64_t mem_access_latency;
+ uint64_t tsx_aux_info;
+ uint64_t unused_2[INTEL_PT_BLK_ITEM_ID_CNT - 4];
+ };
+ uint64_t lbr_0[INTEL_PT_BLK_ITEM_ID_CNT];
+ uint64_t lbr_1[INTEL_PT_BLK_ITEM_ID_CNT];
+ uint64_t lbr_2[INTEL_PT_BLK_ITEM_ID_CNT];
+ uint64_t xmm[INTEL_PT_BLK_ITEM_ID_CNT];
+ };
+ };
+ bool is_32_bit;
+};
+
struct intel_pt_state {
enum intel_pt_sample_type type;
int err;
@@ -81,6 +217,7 @@ struct intel_pt_state {
enum intel_pt_insn_op insn_op;
int insn_len;
char insn[INTEL_PT_INSN_BUF_SZ];
+ struct intel_pt_blk_items items;
};

struct intel_pt_insn;
--
2.20.1