[PATCH v4] perf: cs-etm: update ETM metadata format
Mike Leach
mike.leach at linaro.org
Wed Jan 27 14:33:52 EST 2021
Hi Mathieu,
On Wed, 27 Jan 2021 at 18:32, Mathieu Poirier
<mathieu.poirier at linaro.org> wrote:
>
> On Wed, Jan 27, 2021 at 05:53:50PM +0000, Mike Leach wrote:
> > The current fixed metadata version format (version 0), means that adding
> > metadata parameter items renders files from a previous version of perf
> > unreadable. Per CPU parameters appear in a fixed order, but there is no
> > field to indicate the number of ETM parameters per CPU.
> >
> > This patch updates the per CPU parameter blocks to include a NR_PARAMs
> > value which indicates the number of parameters in the block.
> >
> > The header version is incremented to 1. Fixed ordering is retained,
> > new ETM parameters are added to the end of the list.
> >
> > The reader code is updated to be able to read current version 0 files,
> > For version 1, the reader will read the number of parameters in the
> > per CPU block. This allows the reader to process older or newer files
> > that may have different numbers of parameters than in use at the
> > time perf was built.
>
> Thanks for the re-spin, I will look at it later this week. One question I had
> is if this patch is needed to support the ETE extension Anshuman is working on?
>
It will be once the ETE metadata is defined,, The registers required
to correctly set up the decoder differ than for ETMv4.
Regards
Mike
> >
> > Changes since v3
> > 1. Fixed index bug (Leo)
> >
> > Changes since v2
> > 1. Add error path print to improve --dump logging
> > 2. Replace some hardcoded values with enum consts (Mathieu).
> >
> > Changes since v1 (from Review by Leo):
> > 1. Split printing routine into sub functions per version
> > 2. Renamed NR_PARAMs to NR_TRC_PARAMs to emphasise use as count of trace
> > related parameters, not total block parameter.
> > 3. Misc other fixes.
> >
> > Signed-off-by: Mike Leach <mike.leach at linaro.org>
> > ---
> > tools/perf/arch/arm/util/cs-etm.c | 7 +-
> > tools/perf/util/cs-etm.c | 235 ++++++++++++++++++++++++------
> > tools/perf/util/cs-etm.h | 30 +++-
> > 3 files changed, 223 insertions(+), 49 deletions(-)
> >
> > diff --git a/tools/perf/arch/arm/util/cs-etm.c b/tools/perf/arch/arm/util/cs-etm.c
> > index bd446aba64f7..b0470f2a955a 100644
> > --- a/tools/perf/arch/arm/util/cs-etm.c
> > +++ b/tools/perf/arch/arm/util/cs-etm.c
> > @@ -572,7 +572,7 @@ static void cs_etm_get_metadata(int cpu, u32 *offset,
> > struct auxtrace_record *itr,
> > struct perf_record_auxtrace_info *info)
> > {
> > - u32 increment;
> > + u32 increment, nr_trc_params;
> > u64 magic;
> > struct cs_etm_recording *ptr =
> > container_of(itr, struct cs_etm_recording, itr);
> > @@ -607,6 +607,7 @@ static void cs_etm_get_metadata(int cpu, u32 *offset,
> >
> > /* How much space was used */
> > increment = CS_ETMV4_PRIV_MAX;
> > + nr_trc_params = CS_ETMV4_PRIV_MAX - CS_ETMV4_TRCCONFIGR;
> > } else {
> > magic = __perf_cs_etmv3_magic;
> > /* Get configuration register */
> > @@ -624,11 +625,13 @@ static void cs_etm_get_metadata(int cpu, u32 *offset,
> >
> > /* How much space was used */
> > increment = CS_ETM_PRIV_MAX;
> > + nr_trc_params = CS_ETM_PRIV_MAX - CS_ETM_ETMCR;
> > }
> >
> > /* Build generic header portion */
> > info->priv[*offset + CS_ETM_MAGIC] = magic;
> > info->priv[*offset + CS_ETM_CPU] = cpu;
> > + info->priv[*offset + CS_ETM_NR_TRC_PARAMS] = nr_trc_params;
> > /* Where the next CPU entry should start from */
> > *offset += increment;
> > }
> > @@ -674,7 +677,7 @@ static int cs_etm_info_fill(struct auxtrace_record *itr,
> >
> > /* First fill out the session header */
> > info->type = PERF_AUXTRACE_CS_ETM;
> > - info->priv[CS_HEADER_VERSION_0] = 0;
> > + info->priv[CS_HEADER_VERSION] = CS_HEADER_CURRENT_VERSION;
> > info->priv[CS_PMU_TYPE_CPUS] = type << 32;
> > info->priv[CS_PMU_TYPE_CPUS] |= nr_cpu;
> > info->priv[CS_ETM_SNAPSHOT] = ptr->snapshot_mode;
> > diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c
> > index a2a369e2fbb6..f9af3fe0ed83 100644
> > --- a/tools/perf/util/cs-etm.c
> > +++ b/tools/perf/util/cs-etm.c
> > @@ -2435,7 +2435,7 @@ static bool cs_etm__is_timeless_decoding(struct cs_etm_auxtrace *etm)
> > }
> >
> > static const char * const cs_etm_global_header_fmts[] = {
> > - [CS_HEADER_VERSION_0] = " Header version %llx\n",
> > + [CS_HEADER_VERSION] = " Header version %llx\n",
> > [CS_PMU_TYPE_CPUS] = " PMU type/num cpus %llx\n",
> > [CS_ETM_SNAPSHOT] = " Snapshot %llx\n",
> > };
> > @@ -2443,6 +2443,7 @@ static const char * const cs_etm_global_header_fmts[] = {
> > static const char * const cs_etm_priv_fmts[] = {
> > [CS_ETM_MAGIC] = " Magic number %llx\n",
> > [CS_ETM_CPU] = " CPU %lld\n",
> > + [CS_ETM_NR_TRC_PARAMS] = " NR_TRC_PARAMS %llx\n",
> > [CS_ETM_ETMCR] = " ETMCR %llx\n",
> > [CS_ETM_ETMTRACEIDR] = " ETMTRACEIDR %llx\n",
> > [CS_ETM_ETMCCER] = " ETMCCER %llx\n",
> > @@ -2452,6 +2453,7 @@ static const char * const cs_etm_priv_fmts[] = {
> > static const char * const cs_etmv4_priv_fmts[] = {
> > [CS_ETM_MAGIC] = " Magic number %llx\n",
> > [CS_ETM_CPU] = " CPU %lld\n",
> > + [CS_ETM_NR_TRC_PARAMS] = " NR_TRC_PARAMS %llx\n",
> > [CS_ETMV4_TRCCONFIGR] = " TRCCONFIGR %llx\n",
> > [CS_ETMV4_TRCTRACEIDR] = " TRCTRACEIDR %llx\n",
> > [CS_ETMV4_TRCIDR0] = " TRCIDR0 %llx\n",
> > @@ -2461,26 +2463,167 @@ static const char * const cs_etmv4_priv_fmts[] = {
> > [CS_ETMV4_TRCAUTHSTATUS] = " TRCAUTHSTATUS %llx\n",
> > };
> >
> > -static void cs_etm__print_auxtrace_info(__u64 *val, int num)
> > +static const char * const param_unk_fmt =
> > + " Unknown parameter [%d] %llx\n";
> > +static const char * const magic_unk_fmt =
> > + " Magic number Unknown %llx\n";
> > +
> > +static int cs_etm__print_cpu_metadata_v0(__u64 *val, int *offset)
> > {
> > - int i, j, cpu = 0;
> > + int i = *offset, j, nr_params = 0, fmt_offset;
> > + __u64 magic;
> >
> > - for (i = 0; i < CS_HEADER_VERSION_0_MAX; i++)
> > - fprintf(stdout, cs_etm_global_header_fmts[i], val[i]);
> > + /* check magic value */
> > + magic = val[i + CS_ETM_MAGIC];
> > + if ((magic != __perf_cs_etmv3_magic) &&
> > + (magic != __perf_cs_etmv4_magic)) {
> > + /* failure - note bad magic value */
> > + fprintf(stdout, magic_unk_fmt, magic);
> > + return -EINVAL;
> > + }
> > +
> > + /* print common header block */
> > + fprintf(stdout, cs_etm_priv_fmts[CS_ETM_MAGIC], val[i++]);
> > + fprintf(stdout, cs_etm_priv_fmts[CS_ETM_CPU], val[i++]);
> > +
> > + if (magic == __perf_cs_etmv3_magic) {
> > + nr_params = CS_ETM_NR_TRC_PARAMS_V0;
> > + fmt_offset = CS_ETM_ETMCR;
> > + /* after common block, offset format index past NR_PARAMS */
> > + for (j = fmt_offset; j < nr_params + fmt_offset; j++, i++)
> > + fprintf(stdout, cs_etm_priv_fmts[j], val[i]);
> > + } else if (magic == __perf_cs_etmv4_magic) {
> > + nr_params = CS_ETMV4_NR_TRC_PARAMS_V0;
> > + fmt_offset = CS_ETMV4_TRCCONFIGR;
> > + /* after common block, offset format index past NR_PARAMS */
> > + for (j = fmt_offset; j < nr_params + fmt_offset; j++, i++)
> > + fprintf(stdout, cs_etmv4_priv_fmts[j], val[i]);
> > + }
> > + *offset = i;
> > + return 0;
> > +}
> > +
> > +static int cs_etm__print_cpu_metadata_v1(__u64 *val, int *offset)
> > +{
> > + int i = *offset, j, total_params = 0;
> > + __u64 magic;
> > +
> > + magic = val[i + CS_ETM_MAGIC];
> > + /* total params to print is NR_PARAMS + common block size for v1 */
> > + total_params = val[i + CS_ETM_NR_TRC_PARAMS] + CS_ETM_COMMON_BLK_MAX_V1;
> >
> > - for (i = CS_HEADER_VERSION_0_MAX; cpu < num; cpu++) {
> > - if (val[i] == __perf_cs_etmv3_magic)
> > - for (j = 0; j < CS_ETM_PRIV_MAX; j++, i++)
> > + if (magic == __perf_cs_etmv3_magic) {
> > + for (j = 0; j < total_params; j++, i++) {
> > + /* if newer record - could be excess params */
> > + if (j >= CS_ETM_PRIV_MAX)
> > + fprintf(stdout, param_unk_fmt, j, val[i]);
> > + else
> > fprintf(stdout, cs_etm_priv_fmts[j], val[i]);
> > - else if (val[i] == __perf_cs_etmv4_magic)
> > - for (j = 0; j < CS_ETMV4_PRIV_MAX; j++, i++)
> > + }
> > + } else if (magic == __perf_cs_etmv4_magic) {
> > + for (j = 0; j < total_params; j++, i++) {
> > + /* if newer record - could be excess params */
> > + if (j >= CS_ETMV4_PRIV_MAX)
> > + fprintf(stdout, param_unk_fmt, j, val[i]);
> > + else
> > fprintf(stdout, cs_etmv4_priv_fmts[j], val[i]);
> > - else
> > - /* failure.. return */
> > + }
> > + } else {
> > + /* failure - note bad magic value and error out */
> > + fprintf(stdout, magic_unk_fmt, magic);
> > + return -EINVAL;
> > + }
> > + *offset = i;
> > + return 0;
> > +}
> > +
> > +static void cs_etm__print_auxtrace_info(__u64 *val, int num)
> > +{
> > + int i, cpu = 0, version, err;
> > +
> > + /* bail out early on bad header version */
> > + version = val[0];
> > + if (version > CS_HEADER_CURRENT_VERSION) {
> > + /* failure.. return */
> > + fprintf(stdout, " Unknown Header Version = %x, ", version);
> > + fprintf(stdout, "Version supported <= %x\n", CS_HEADER_CURRENT_VERSION);
> > + return;
> > + }
> > +
> > + for (i = 0; i < CS_HEADER_VERSION_MAX; i++)
> > + fprintf(stdout, cs_etm_global_header_fmts[i], val[i]);
> > +
> > + for (i = CS_HEADER_VERSION_MAX; cpu < num; cpu++) {
> > + if (version == 0)
> > + err = cs_etm__print_cpu_metadata_v0(val, &i);
> > + else if (version == 1)
> > + err = cs_etm__print_cpu_metadata_v1(val, &i);
> > + if (err)
> > return;
> > }
> > }
> >
> > +/*
> > + * Read a single cpu parameter block from the auxtrace_info priv block.
> > + *
> > + * For version 1 there is a per cpu nr_params entry. If we are handling
> > + * version 1 file, then there may be less, the same, or more params
> > + * indicated by this value than the compile time number we understand.
> > + *
> > + * For a version 0 info block, there are a fixed number, and we need to
> > + * fill out the nr_param value in the metadata we create.
> > + */
> > +static u64 *cs_etm__create_meta_blk(u64 *buff_in, int *buff_in_offset,
> > + int out_blk_size, int nr_params_v0)
> > +{
> > + u64 *metadata = NULL;
> > + int hdr_version;
> > + int nr_in_params, nr_out_params, nr_cmn_params;
> > + int i, k;
> > +
> > + metadata = zalloc(sizeof(*metadata) * out_blk_size);
> > + if (!metadata)
> > + return NULL;
> > +
> > + /* read block current index & version */
> > + i = *buff_in_offset;
> > + hdr_version = buff_in[CS_HEADER_VERSION];
> > +
> > + if (!hdr_version) {
> > + /* read version 0 info block into a version 1 metadata block */
> > + nr_in_params = nr_params_v0;
> > + metadata[CS_ETM_MAGIC] = buff_in[i + CS_ETM_MAGIC];
> > + metadata[CS_ETM_CPU] = buff_in[i + CS_ETM_CPU];
> > + metadata[CS_ETM_NR_TRC_PARAMS] = nr_in_params;
> > + /* remaining block params at offset +1 from source */
> > + for (k = CS_ETM_ETMCR - 1; k < nr_in_params; k++)
> > + metadata[k+1] = buff_in[i + k];
> > + /* version 0 has 2 common params */
> > + nr_cmn_params = 2;
> > + } else {
> > + /* read version 1 info block - input and output nr_params may differ */
> > + /* version 1 has 3 common params */
> > + nr_cmn_params = 3;
> > + nr_in_params = buff_in[i + CS_ETM_NR_TRC_PARAMS];
> > +
> > + /* if input has more params than output - skip excess */
> > + nr_out_params = nr_in_params + nr_cmn_params;
> > + if (nr_out_params > out_blk_size)
> > + nr_out_params = out_blk_size;
> > +
> > + for (k = CS_ETM_MAGIC; k < nr_out_params; k++)
> > + metadata[k] = buff_in[i + k];
> > +
> > + /* record the actual nr params we copied */
> > + metadata[CS_ETM_NR_TRC_PARAMS] = nr_out_params - nr_cmn_params;
> > + }
> > +
> > + /* adjust in offset by number of in params used */
> > + i += nr_in_params + nr_cmn_params;
> > + *buff_in_offset = i;
> > + return metadata;
> > +}
> > +
> > int cs_etm__process_auxtrace_info(union perf_event *event,
> > struct perf_session *session)
> > {
> > @@ -2492,11 +2635,12 @@ int cs_etm__process_auxtrace_info(union perf_event *event,
> > int info_header_size;
> > int total_size = auxtrace_info->header.size;
> > int priv_size = 0;
> > - int num_cpu;
> > - int err = 0, idx = -1;
> > - int i, j, k;
> > + int num_cpu, trcidr_idx;
> > + int err = 0;
> > + int i, j;
> > u64 *ptr, *hdr = NULL;
> > u64 **metadata = NULL;
> > + u64 hdr_version;
> >
> > /*
> > * sizeof(auxtrace_info_event::type) +
> > @@ -2512,16 +2656,21 @@ int cs_etm__process_auxtrace_info(union perf_event *event,
> > /* First the global part */
> > ptr = (u64 *) auxtrace_info->priv;
> >
> > - /* Look for version '0' of the header */
> > - if (ptr[0] != 0)
> > + /* Look for version of the header */
> > + hdr_version = ptr[0];
> > + if (hdr_version > CS_HEADER_CURRENT_VERSION) {
> > + /* print routine will print an error on bad version */
> > + if (dump_trace)
> > + cs_etm__print_auxtrace_info(auxtrace_info->priv, 0);
> > return -EINVAL;
> > + }
> >
> > - hdr = zalloc(sizeof(*hdr) * CS_HEADER_VERSION_0_MAX);
> > + hdr = zalloc(sizeof(*hdr) * CS_HEADER_VERSION_MAX);
> > if (!hdr)
> > return -ENOMEM;
> >
> > /* Extract header information - see cs-etm.h for format */
> > - for (i = 0; i < CS_HEADER_VERSION_0_MAX; i++)
> > + for (i = 0; i < CS_HEADER_VERSION_MAX; i++)
> > hdr[i] = ptr[i];
> > num_cpu = hdr[CS_PMU_TYPE_CPUS] & 0xffffffff;
> > pmu_type = (unsigned int) ((hdr[CS_PMU_TYPE_CPUS] >> 32) &
> > @@ -2552,35 +2701,31 @@ int cs_etm__process_auxtrace_info(union perf_event *event,
> > */
> > for (j = 0; j < num_cpu; j++) {
> > if (ptr[i] == __perf_cs_etmv3_magic) {
> > - metadata[j] = zalloc(sizeof(*metadata[j]) *
> > - CS_ETM_PRIV_MAX);
> > - if (!metadata[j]) {
> > - err = -ENOMEM;
> > - goto err_free_metadata;
> > - }
> > - for (k = 0; k < CS_ETM_PRIV_MAX; k++)
> > - metadata[j][k] = ptr[i + k];
> > + metadata[j] =
> > + cs_etm__create_meta_blk(ptr, &i,
> > + CS_ETM_PRIV_MAX,
> > + CS_ETM_NR_TRC_PARAMS_V0);
> >
> > /* The traceID is our handle */
> > - idx = metadata[j][CS_ETM_ETMTRACEIDR];
> > - i += CS_ETM_PRIV_MAX;
> > + trcidr_idx = CS_ETM_ETMTRACEIDR;
> > +
> > } else if (ptr[i] == __perf_cs_etmv4_magic) {
> > - metadata[j] = zalloc(sizeof(*metadata[j]) *
> > - CS_ETMV4_PRIV_MAX);
> > - if (!metadata[j]) {
> > - err = -ENOMEM;
> > - goto err_free_metadata;
> > - }
> > - for (k = 0; k < CS_ETMV4_PRIV_MAX; k++)
> > - metadata[j][k] = ptr[i + k];
> > + metadata[j] =
> > + cs_etm__create_meta_blk(ptr, &i,
> > + CS_ETMV4_PRIV_MAX,
> > + CS_ETMV4_NR_TRC_PARAMS_V0);
> >
> > /* The traceID is our handle */
> > - idx = metadata[j][CS_ETMV4_TRCTRACEIDR];
> > - i += CS_ETMV4_PRIV_MAX;
> > + trcidr_idx = CS_ETMV4_TRCTRACEIDR;
> > + }
> > +
> > + if (!metadata[j]) {
> > + err = -ENOMEM;
> > + goto err_free_metadata;
> > }
> >
> > /* Get an RB node for this CPU */
> > - inode = intlist__findnew(traceid_list, idx);
> > + inode = intlist__findnew(traceid_list, metadata[j][trcidr_idx]);
> >
> > /* Something went wrong, no need to continue */
> > if (!inode) {
> > @@ -2601,7 +2746,7 @@ int cs_etm__process_auxtrace_info(union perf_event *event,
> > }
> >
> > /*
> > - * Each of CS_HEADER_VERSION_0_MAX, CS_ETM_PRIV_MAX and
> > + * Each of CS_HEADER_VERSION_MAX, CS_ETM_PRIV_MAX and
> > * CS_ETMV4_PRIV_MAX mark how many double words are in the
> > * global metadata, and each cpu's metadata respectively.
> > * The following tests if the correct number of double words was
> > @@ -2703,6 +2848,12 @@ int cs_etm__process_auxtrace_info(union perf_event *event,
> > intlist__delete(traceid_list);
> > err_free_hdr:
> > zfree(&hdr);
> > -
> > + /*
> > + * At this point, as a minimum we have valid header. Dump the rest of
> > + * the info section - the print routines will error out on structural
> > + * issues.
> > + */
> > + if (dump_trace)
> > + cs_etm__print_auxtrace_info(auxtrace_info->priv, num_cpu);
> > return err;
> > }
> > diff --git a/tools/perf/util/cs-etm.h b/tools/perf/util/cs-etm.h
> > index 4ad925d6d799..e153d02df0de 100644
> > --- a/tools/perf/util/cs-etm.h
> > +++ b/tools/perf/util/cs-etm.h
> > @@ -17,23 +17,37 @@ struct perf_session;
> > */
> > enum {
> > /* Starting with 0x0 */
> > - CS_HEADER_VERSION_0,
> > + CS_HEADER_VERSION,
> > /* PMU->type (32 bit), total # of CPUs (32 bit) */
> > CS_PMU_TYPE_CPUS,
> > CS_ETM_SNAPSHOT,
> > - CS_HEADER_VERSION_0_MAX,
> > + CS_HEADER_VERSION_MAX,
> > };
> >
> > +/*
> > + * Update the version for new format.
> > + *
> > + * New version 1 format adds a param count to the per cpu metadata.
> > + * This allows easy adding of new metadata parameters.
> > + * Requires that new params always added after current ones.
> > + * Also allows client reader to handle file versions that are different by
> > + * checking the number of params in the file vs the number expected.
> > + */
> > +#define CS_HEADER_CURRENT_VERSION 1
> > +
> > /* Beginning of header common to both ETMv3 and V4 */
> > enum {
> > CS_ETM_MAGIC,
> > CS_ETM_CPU,
> > + /* Number of trace config params in following ETM specific block */
> > + CS_ETM_NR_TRC_PARAMS,
> > + CS_ETM_COMMON_BLK_MAX_V1,
> > };
> >
> > /* ETMv3/PTM metadata */
> > enum {
> > /* Dynamic, configurable parameters */
> > - CS_ETM_ETMCR = CS_ETM_CPU + 1,
> > + CS_ETM_ETMCR = CS_ETM_COMMON_BLK_MAX_V1,
> > CS_ETM_ETMTRACEIDR,
> > /* RO, taken from sysFS */
> > CS_ETM_ETMCCER,
> > @@ -41,10 +55,13 @@ enum {
> > CS_ETM_PRIV_MAX,
> > };
> >
> > +/* define fixed version 0 length - allow new format reader to read old files. */
> > +#define CS_ETM_NR_TRC_PARAMS_V0 (CS_ETM_ETMIDR - CS_ETM_ETMCR + 1)
> > +
> > /* ETMv4 metadata */
> > enum {
> > /* Dynamic, configurable parameters */
> > - CS_ETMV4_TRCCONFIGR = CS_ETM_CPU + 1,
> > + CS_ETMV4_TRCCONFIGR = CS_ETM_COMMON_BLK_MAX_V1,
> > CS_ETMV4_TRCTRACEIDR,
> > /* RO, taken from sysFS */
> > CS_ETMV4_TRCIDR0,
> > @@ -55,6 +72,9 @@ enum {
> > CS_ETMV4_PRIV_MAX,
> > };
> >
> > +/* define fixed version 0 length - allow new format reader to read old files. */
> > +#define CS_ETMV4_NR_TRC_PARAMS_V0 (CS_ETMV4_TRCAUTHSTATUS - CS_ETMV4_TRCCONFIGR + 1)
> > +
> > /*
> > * ETMv3 exception encoding number:
> > * See Embedded Trace Macrocell spcification (ARM IHI 0014Q)
> > @@ -162,7 +182,7 @@ struct cs_etm_packet_queue {
> >
> > #define BMVAL(val, lsb, msb) ((val & GENMASK(msb, lsb)) >> lsb)
> >
> > -#define CS_ETM_HEADER_SIZE (CS_HEADER_VERSION_0_MAX * sizeof(u64))
> > +#define CS_ETM_HEADER_SIZE (CS_HEADER_VERSION_MAX * sizeof(u64))
> >
> > #define __perf_cs_etmv3_magic 0x3030303030303030ULL
> > #define __perf_cs_etmv4_magic 0x4040404040404040ULL
> > --
> > 2.17.1
> >
--
Mike Leach
Principal Engineer, ARM Ltd.
Manchester Design Centre. UK
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