Re: [PATCH 01/11] perf intel-pt: Add new packets for PEBS via PT

Arnaldo Carvalho de Melo
2019-06-12T12:41:47Z

Em Wed, Jun 12, 2019 at 08:58:00AM +0300, Adrian Hunter escreveu:
> On 12/06/19 3:09 AM, Arnaldo Carvalho de Melo wrote:
> > Em Mon, Jun 10, 2019 at 10:27:53AM +0300, Adrian Hunter escreveu:
> >> Add 3 new packets to supports PEBS via PT, namely Block Begin Packet (BBP),
> >> Block Item Packet (BIP) and Block End Packet (BEP). PEBS data is encoded
> >> into multiple BIP packets that come between BBP and BEP. The BEP packet
> >> might be associated with a FUP packet. That is indicated by using a
> >> separate packet type (INTEL_PT_BEP_IP) similar to other packets types with
> >> the _IP suffix.
> >>
> >> Refer to the Intel SDM for more information about PEBS via PT.
> >
> > In these cases would be nice to provide an URL and page number, for
> > convenience.
>
> Intel SDM:
>
> https://software.intel.com/en-us/articles/intel-sdm
>
> May 2019 version: Vol. 3B 18.5.5.2 PEBS output to Intel® Processor Trace

Thanks! I'll add to that cset.

What about the kernel bits?

- Arnaldo

> >
> > - Arnaldo
> >
> >> Decoding of BIP packets conflicts with single-byte TNT packets. Since BIP
> >> packets only occur in the context of a block (i.e. between BBP and BEP),
> >> that context must be recorded and passed to the packet decoder.
> >>
> >> Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
> >> ---
> >> .../util/intel-pt-decoder/intel-pt-decoder.c | 38 ++++-
> >> .../intel-pt-decoder/intel-pt-pkt-decoder.c | 140 +++++++++++++++++-
> >> .../intel-pt-decoder/intel-pt-pkt-decoder.h | 21 ++-
> >> tools/perf/util/intel-pt.c | 3 +-
> >> 4 files changed, 193 insertions(+), 9 deletions(-)
> >>
> >> 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 9eb778f9c911..44218f9cf16a 100644
> >> --- a/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c
> >> +++ b/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c
> >> @@ -140,6 +140,7 @@ struct intel_pt_decoder {
> >> int mtc_shift;
> >> struct intel_pt_stack stack;
> >> enum intel_pt_pkt_state pkt_state;
> >> + enum intel_pt_pkt_ctx pkt_ctx;
> >> struct intel_pt_pkt packet;
> >> struct intel_pt_pkt tnt;
> >> int pkt_step;
> >> @@ -558,7 +559,7 @@ static int intel_pt_get_split_packet(struct intel_pt_decoder *decoder)
> >> memcpy(buf + len, decoder->buf, n);
> >> len += n;
> >>
> >> - ret = intel_pt_get_packet(buf, len, &decoder->packet);
> >> + ret = intel_pt_get_packet(buf, len, &decoder->packet, &decoder->pkt_ctx);
> >> if (ret < (int)old_len) {
> >> decoder->next_buf = decoder->buf;
> >> decoder->next_len = decoder->len;
> >> @@ -593,6 +594,7 @@ static int intel_pt_pkt_lookahead(struct intel_pt_decoder *decoder,
> >> {
> >> struct intel_pt_pkt_info pkt_info;
> >> const unsigned char *buf = decoder->buf;
> >> + enum intel_pt_pkt_ctx pkt_ctx = decoder->pkt_ctx;
> >> size_t len = decoder->len;
> >> int ret;
> >>
> >> @@ -611,7 +613,8 @@ static int intel_pt_pkt_lookahead(struct intel_pt_decoder *decoder,
> >> if (!len)
> >> return INTEL_PT_NEED_MORE_BYTES;
> >>
> >> - ret = intel_pt_get_packet(buf, len, &pkt_info.packet);
> >> + ret = intel_pt_get_packet(buf, len, &pkt_info.packet,
> >> + &pkt_ctx);
> >> if (!ret)
> >> return INTEL_PT_NEED_MORE_BYTES;
> >> if (ret < 0)
> >> @@ -686,6 +689,10 @@ static int intel_pt_calc_cyc_cb(struct intel_pt_pkt_info *pkt_info)
> >> case INTEL_PT_MNT:
> >> case INTEL_PT_PTWRITE:
> >> case INTEL_PT_PTWRITE_IP:
> >> + case INTEL_PT_BBP:
> >> + case INTEL_PT_BIP:
> >> + case INTEL_PT_BEP:
> >> + case INTEL_PT_BEP_IP:
> >> return 0;
> >>
> >> case INTEL_PT_MTC:
> >> @@ -878,7 +885,7 @@ static int intel_pt_get_next_packet(struct intel_pt_decoder *decoder)
> >> }
> >>
> >> ret = intel_pt_get_packet(decoder->buf, decoder->len,
> >> - &decoder->packet);
> >> + &decoder->packet, &decoder->pkt_ctx);
> >> if (ret == INTEL_PT_NEED_MORE_BYTES && BITS_PER_LONG == 32 &&
> >> decoder->len < INTEL_PT_PKT_MAX_SZ && !decoder->next_buf) {
> >> ret = intel_pt_get_split_packet(decoder);
> >> @@ -1624,6 +1631,10 @@ static int intel_pt_walk_psbend(struct intel_pt_decoder *decoder)
> >> case INTEL_PT_MWAIT:
> >> case INTEL_PT_PWRE:
> >> case INTEL_PT_PWRX:
> >> + case INTEL_PT_BBP:
> >> + case INTEL_PT_BIP:
> >> + case INTEL_PT_BEP:
> >> + case INTEL_PT_BEP_IP:
> >> decoder->have_tma = false;
> >> intel_pt_log("ERROR: Unexpected packet\n");
> >> err = -EAGAIN;
> >> @@ -1717,6 +1728,10 @@ static int intel_pt_walk_fup_tip(struct intel_pt_decoder *decoder)
> >> case INTEL_PT_MWAIT:
> >> case INTEL_PT_PWRE:
> >> case INTEL_PT_PWRX:
> >> + case INTEL_PT_BBP:
> >> + case INTEL_PT_BIP:
> >> + case INTEL_PT_BEP:
> >> + case INTEL_PT_BEP_IP:
> >> intel_pt_log("ERROR: Missing TIP after FUP\n");
> >> decoder->pkt_state = INTEL_PT_STATE_ERR3;
> >> decoder->pkt_step = 0;
> >> @@ -2038,6 +2053,12 @@ static int intel_pt_walk_trace(struct intel_pt_decoder *decoder)
> >> decoder->state.pwrx_payload = decoder->packet.payload;
> >> return 0;
> >>
> >> + case INTEL_PT_BBP:
> >> + case INTEL_PT_BIP:
> >> + case INTEL_PT_BEP:
> >> + case INTEL_PT_BEP_IP:
> >> + break;
> >> +
> >> default:
> >> return intel_pt_bug(decoder);
> >> }
> >> @@ -2076,6 +2097,10 @@ static int intel_pt_walk_psb(struct intel_pt_decoder *decoder)
> >> case INTEL_PT_MWAIT:
> >> case INTEL_PT_PWRE:
> >> case INTEL_PT_PWRX:
> >> + case INTEL_PT_BBP:
> >> + case INTEL_PT_BIP:
> >> + case INTEL_PT_BEP:
> >> + case INTEL_PT_BEP_IP:
> >> intel_pt_log("ERROR: Unexpected packet\n");
> >> err = -ENOENT;
> >> goto out;
> >> @@ -2282,6 +2307,10 @@ static int intel_pt_walk_to_ip(struct intel_pt_decoder *decoder)
> >> case INTEL_PT_MWAIT:
> >> case INTEL_PT_PWRE:
> >> case INTEL_PT_PWRX:
> >> + case INTEL_PT_BBP:
> >> + case INTEL_PT_BIP:
> >> + case INTEL_PT_BEP:
> >> + case INTEL_PT_BEP_IP:
> >> default:
> >> break;
> >> }
> >> @@ -2632,11 +2661,12 @@ static unsigned char *intel_pt_last_psb(unsigned char *buf, size_t len)
> >> static bool intel_pt_next_tsc(unsigned char *buf, size_t len, uint64_t *tsc,
> >> size_t *rem)
> >> {
> >> + enum intel_pt_pkt_ctx ctx = INTEL_PT_NO_CTX;
> >> struct intel_pt_pkt packet;
> >> int ret;
> >>
> >> while (len) {
> >> - ret = intel_pt_get_packet(buf, len, &packet);
> >> + ret = intel_pt_get_packet(buf, len, &packet, &ctx);
> >> if (ret <= 0)
> >> return false;
> >> if (packet.type == INTEL_PT_TSC) {
> >> diff --git a/tools/perf/util/intel-pt-decoder/intel-pt-pkt-decoder.c b/tools/perf/util/intel-pt-decoder/intel-pt-pkt-decoder.c
> >> index d426761a549d..2b2793b339c0 100644
> >> --- a/tools/perf/util/intel-pt-decoder/intel-pt-pkt-decoder.c
> >> +++ b/tools/perf/util/intel-pt-decoder/intel-pt-pkt-decoder.c
> >> @@ -71,6 +71,10 @@ static const char * const packet_name[] = {
> >> [INTEL_PT_MWAIT] = "MWAIT",
> >> [INTEL_PT_PWRE] = "PWRE",
> >> [INTEL_PT_PWRX] = "PWRX",
> >> + [INTEL_PT_BBP] = "BBP",
> >> + [INTEL_PT_BIP] = "BIP",
> >> + [INTEL_PT_BEP] = "BEP",
> >> + [INTEL_PT_BEP_IP] = "BEP",
> >> };
> >>
> >> const char *intel_pt_pkt_name(enum intel_pt_pkt_type type)
> >> @@ -289,6 +293,55 @@ static int intel_pt_get_pwrx(const unsigned char *buf, size_t len,
> >> return 7;
> >> }
> >>
> >> +static int intel_pt_get_bbp(const unsigned char *buf, size_t len,
> >> + struct intel_pt_pkt *packet)
> >> +{
> >> + if (len < 3)
> >> + return INTEL_PT_NEED_MORE_BYTES;
> >> + packet->type = INTEL_PT_BBP;
> >> + packet->count = buf[2] >> 7;
> >> + packet->payload = buf[2] & 0x1f;
> >> + return 3;
> >> +}
> >> +
> >> +static int intel_pt_get_bip_4(const unsigned char *buf, size_t len,
> >> + struct intel_pt_pkt *packet)
> >> +{
> >> + if (len < 5)
> >> + return INTEL_PT_NEED_MORE_BYTES;
> >> + packet->type = INTEL_PT_BIP;
> >> + packet->count = buf[0] >> 3;
> >> + memcpy_le64(&packet->payload, buf + 1, 4);
> >> + return 5;
> >> +}
> >> +
> >> +static int intel_pt_get_bip_8(const unsigned char *buf, size_t len,
> >> + struct intel_pt_pkt *packet)
> >> +{
> >> + if (len < 9)
> >> + return INTEL_PT_NEED_MORE_BYTES;
> >> + packet->type = INTEL_PT_BIP;
> >> + packet->count = buf[0] >> 3;
> >> + memcpy_le64(&packet->payload, buf + 1, 8);
> >> + return 9;
> >> +}
> >> +
> >> +static int intel_pt_get_bep(size_t len, struct intel_pt_pkt *packet)
> >> +{
> >> + if (len < 2)
> >> + return INTEL_PT_NEED_MORE_BYTES;
> >> + packet->type = INTEL_PT_BEP;
> >> + return 2;
> >> +}
> >> +
> >> +static int intel_pt_get_bep_ip(size_t len, struct intel_pt_pkt *packet)
> >> +{
> >> + if (len < 2)
> >> + return INTEL_PT_NEED_MORE_BYTES;
> >> + packet->type = INTEL_PT_BEP_IP;
> >> + return 2;
> >> +}
> >> +
> >> static int intel_pt_get_ext(const unsigned char *buf, size_t len,
> >> struct intel_pt_pkt *packet)
> >> {
> >> @@ -329,6 +382,12 @@ static int intel_pt_get_ext(const unsigned char *buf, size_t len,
> >> return intel_pt_get_pwre(buf, len, packet);
> >> case 0xA2: /* PWRX */
> >> return intel_pt_get_pwrx(buf, len, packet);
> >> + case 0x63: /* BBP */
> >> + return intel_pt_get_bbp(buf, len, packet);
> >> + case 0x33: /* BEP no IP */
> >> + return intel_pt_get_bep(len, packet);
> >> + case 0xb3: /* BEP with IP */
> >> + return intel_pt_get_bep_ip(len, packet);
> >> default:
> >> return INTEL_PT_BAD_PACKET;
> >> }
> >> @@ -477,7 +536,8 @@ static int intel_pt_get_mtc(const unsigned char *buf, size_t len,
> >> }
> >>
> >> static int intel_pt_do_get_packet(const unsigned char *buf, size_t len,
> >> - struct intel_pt_pkt *packet)
> >> + struct intel_pt_pkt *packet,
> >> + enum intel_pt_pkt_ctx ctx)
> >> {
> >> unsigned int byte;
> >>
> >> @@ -487,6 +547,22 @@ static int intel_pt_do_get_packet(const unsigned char *buf, size_t len,
> >> return INTEL_PT_NEED_MORE_BYTES;
> >>
> >> byte = buf[0];
> >> +
> >> + switch (ctx) {
> >> + case INTEL_PT_NO_CTX:
> >> + break;
> >> + case INTEL_PT_BLK_4_CTX:
> >> + if ((byte & 0x7) == 4)
> >> + return intel_pt_get_bip_4(buf, len, packet);
> >> + break;
> >> + case INTEL_PT_BLK_8_CTX:
> >> + if ((byte & 0x7) == 4)
> >> + return intel_pt_get_bip_8(buf, len, packet);
> >> + break;
> >> + default:
> >> + break;
> >> + };
> >> +
> >> if (!(byte & BIT(0))) {
> >> if (byte == 0)
> >> return intel_pt_get_pad(packet);
> >> @@ -525,15 +601,65 @@ static int intel_pt_do_get_packet(const unsigned char *buf, size_t len,
> >> }
> >> }
> >>
> >> +void intel_pt_upd_pkt_ctx(const struct intel_pt_pkt *packet,
> >> + enum intel_pt_pkt_ctx *ctx)
> >> +{
> >> + switch (packet->type) {
> >> + case INTEL_PT_BAD:
> >> + case INTEL_PT_PAD:
> >> + case INTEL_PT_TSC:
> >> + case INTEL_PT_TMA:
> >> + case INTEL_PT_MTC:
> >> + case INTEL_PT_FUP:
> >> + case INTEL_PT_CYC:
> >> + case INTEL_PT_CBR:
> >> + case INTEL_PT_MNT:
> >> + case INTEL_PT_EXSTOP:
> >> + case INTEL_PT_EXSTOP_IP:
> >> + case INTEL_PT_PWRE:
> >> + case INTEL_PT_PWRX:
> >> + case INTEL_PT_BIP:
> >> + break;
> >> + case INTEL_PT_TNT:
> >> + case INTEL_PT_TIP:
> >> + case INTEL_PT_TIP_PGD:
> >> + case INTEL_PT_TIP_PGE:
> >> + case INTEL_PT_MODE_EXEC:
> >> + case INTEL_PT_MODE_TSX:
> >> + case INTEL_PT_PIP:
> >> + case INTEL_PT_OVF:
> >> + case INTEL_PT_VMCS:
> >> + case INTEL_PT_TRACESTOP:
> >> + case INTEL_PT_PSB:
> >> + case INTEL_PT_PSBEND:
> >> + case INTEL_PT_PTWRITE:
> >> + case INTEL_PT_PTWRITE_IP:
> >> + case INTEL_PT_MWAIT:
> >> + case INTEL_PT_BEP:
> >> + case INTEL_PT_BEP_IP:
> >> + *ctx = INTEL_PT_NO_CTX;
> >> + break;
> >> + case INTEL_PT_BBP:
> >> + if (packet->count)
> >> + *ctx = INTEL_PT_BLK_4_CTX;
> >> + else
> >> + *ctx = INTEL_PT_BLK_8_CTX;
> >> + break;
> >> + default:
> >> + break;
> >> + }
> >> +}
> >> +
> >> int intel_pt_get_packet(const unsigned char *buf, size_t len,
> >> - struct intel_pt_pkt *packet)
> >> + struct intel_pt_pkt *packet, enum intel_pt_pkt_ctx *ctx)
> >> {
> >> int ret;
> >>
> >> - ret = intel_pt_do_get_packet(buf, len, packet);
> >> + ret = intel_pt_do_get_packet(buf, len, packet, *ctx);
> >> if (ret > 0) {
> >> while (ret < 8 && len > (size_t)ret && !buf[ret])
> >> ret += 1;
> >> + intel_pt_upd_pkt_ctx(packet, ctx);
> >> }
> >> return ret;
> >> }
> >> @@ -611,8 +737,10 @@ int intel_pt_pkt_desc(const struct intel_pt_pkt *packet, char *buf,
> >> return snprintf(buf, buf_len, "%s 0x%llx IP:0", name, payload);
> >> case INTEL_PT_PTWRITE_IP:
> >> return snprintf(buf, buf_len, "%s 0x%llx IP:1", name, payload);
> >> + case INTEL_PT_BEP:
> >> case INTEL_PT_EXSTOP:
> >> return snprintf(buf, buf_len, "%s IP:0", name);
> >> + case INTEL_PT_BEP_IP:
> >> case INTEL_PT_EXSTOP_IP:
> >> return snprintf(buf, buf_len, "%s IP:1", name);
> >> case INTEL_PT_MWAIT:
> >> @@ -630,6 +758,12 @@ int intel_pt_pkt_desc(const struct intel_pt_pkt *packet, char *buf,
> >> (unsigned int)((payload >> 4) & 0xf),
> >> (unsigned int)(payload & 0xf),
> >> (unsigned int)((payload >> 8) & 0xf));
> >> + case INTEL_PT_BBP:
> >> + return snprintf(buf, buf_len, "%s SZ %s-byte Type 0x%llx",
> >> + name, packet->count ? "4" : "8", payload);
> >> + case INTEL_PT_BIP:
> >> + return snprintf(buf, buf_len, "%s ID 0x%02x Value 0x%llx",
> >> + name, packet->count, payload);
> >> default:
> >> break;
> >> }
> >> diff --git a/tools/perf/util/intel-pt-decoder/intel-pt-pkt-decoder.h b/tools/perf/util/intel-pt-decoder/intel-pt-pkt-decoder.h
> >> index 73ddc3a88d07..682b35282abc 100644
> >> --- a/tools/perf/util/intel-pt-decoder/intel-pt-pkt-decoder.h
> >> +++ b/tools/perf/util/intel-pt-decoder/intel-pt-pkt-decoder.h
> >> @@ -59,6 +59,10 @@ enum intel_pt_pkt_type {
> >> INTEL_PT_MWAIT,
> >> INTEL_PT_PWRE,
> >> INTEL_PT_PWRX,
> >> + INTEL_PT_BBP,
> >> + INTEL_PT_BIP,
> >> + INTEL_PT_BEP,
> >> + INTEL_PT_BEP_IP,
> >> };
> >>
> >> struct intel_pt_pkt {
> >> @@ -67,10 +71,25 @@ struct intel_pt_pkt {
> >> uint64_t payload;
> >> };
> >>
> >> +/*
> >> + * Decoding of BIP packets conflicts with single-byte TNT packets. Since BIP
> >> + * packets only occur in the context of a block (i.e. between BBP and BEP), that
> >> + * context must be recorded and passed to the packet decoder.
> >> + */
> >> +enum intel_pt_pkt_ctx {
> >> + INTEL_PT_NO_CTX, /* BIP packets are invalid */
> >> + INTEL_PT_BLK_4_CTX, /* 4-byte BIP packets */
> >> + INTEL_PT_BLK_8_CTX, /* 8-byte BIP packets */
> >> +};
> >> +
> >> const char *intel_pt_pkt_name(enum intel_pt_pkt_type);
> >>
> >> int intel_pt_get_packet(const unsigned char *buf, size_t len,
> >> - struct intel_pt_pkt *packet);
> >> + struct intel_pt_pkt *packet,
> >> + enum intel_pt_pkt_ctx *ctx);
> >> +
> >> +void intel_pt_upd_pkt_ctx(const struct intel_pt_pkt *packet,
> >> + enum intel_pt_pkt_ctx *ctx);
> >>
> >> int intel_pt_pkt_desc(const struct intel_pt_pkt *packet, char *buf, size_t len);
> >>
> >> diff --git a/tools/perf/util/intel-pt.c b/tools/perf/util/intel-pt.c
> >> index 3cff8fe2eaa0..f43d3ac2db8b 100644
> >> --- a/tools/perf/util/intel-pt.c
> >> +++ b/tools/perf/util/intel-pt.c
> >> @@ -174,13 +174,14 @@ static void intel_pt_dump(struct intel_pt *pt __maybe_unused,
> >> int ret, pkt_len, i;
> >> char desc[INTEL_PT_PKT_DESC_MAX];
> >> const char *color = PERF_COLOR_BLUE;
> >> + enum intel_pt_pkt_ctx ctx = INTEL_PT_NO_CTX;
> >>
> >> color_fprintf(stdout, color,
> >> ". ... Intel Processor Trace data: size %zu bytes\n",
> >> len);
> >>
> >> while (len) {
> >> - ret = intel_pt_get_packet(buf, len, &packet);
> >> + ret = intel_pt_get_packet(buf, len, &packet, &ctx);
> >> if (ret > 0)
> >> pkt_len = ret;
> >> else
> >> --
> >> 2.17.1
> >

--

- Arnaldo