Re: [PATCH v3] perf: cs-etm: update ETM metadata format

Hi Mike,

On Tue, Jan 19, 2021 at 06:01:10PM +0000, Mike Leach wrote:

[...]

+/*

• • 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; k < nr_in_params; k++)
  

• 	metadata[k+1] = buff_in[i + k];
  

Here it misses to copy data into metadata[CS_ETM_ETMCR], you could see it starts to copy from offset 3 (k = CS_ETM_ETMCR) from buff_in, actually it's the item for CS_ETM_ETMTRACEIDR in the metadata v0.

So need to change the logic as below; please confirm if I misunderstand or not.

for (k = CS_ETM_ETMCR - 1; k < nr_in_params; k++) metadata[k+1] = buff_in[i + k];

Except this issue for ETMv3, I didn't find any other logic issue for ETMv4; I tested and confirmed the tool shows the consistent result for metadata v0 before and after applying this patch; and it handles metadata v1 correctly.

So after fixed the issue for ETMv3, the change looks good to me:

Reviewed-by: Leo Yan leo.yan@linaro.org Tested-by: Leo Yan leo.yan@linaro.org

Thanks!

• /* 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