It's possible for CoreSight to trace PID in either CONTEXTIDR_EL1 or
CONTEXTIDR_EL2, the PID format info is used to distinguish the PID
is traced in which register.
This patch saves PID format into the metadata when record.
Signed-off-by: Leo Yan <[email protected]>
---
tools/perf/arch/arm/util/cs-etm.c | 21 +++++++++++++++++++++
tools/perf/util/cs-etm.c | 2 ++
tools/perf/util/cs-etm.h | 2 ++
3 files changed, 25 insertions(+)
diff --git a/tools/perf/arch/arm/util/cs-etm.c b/tools/perf/arch/arm/util/cs-etm.c
index fad7b6e13ccc..ee78df3b1b07 100644
--- a/tools/perf/arch/arm/util/cs-etm.c
+++ b/tools/perf/arch/arm/util/cs-etm.c
@@ -613,6 +613,7 @@ static void cs_etm_get_metadata(int cpu, u32 *offset,
struct cs_etm_recording *ptr =
container_of(itr, struct cs_etm_recording, itr);
struct perf_pmu *cs_etm_pmu = ptr->cs_etm_pmu;
+ u64 pid_fmt;
/* first see what kind of tracer this cpu is affined to */
if (cs_etm_is_etmv4(itr, cpu)) {
@@ -641,6 +642,16 @@ static void cs_etm_get_metadata(int cpu, u32 *offset,
metadata_etmv4_ro
[CS_ETMV4_TRCAUTHSTATUS]);
+ /*
+ * The PID format will be used when decode the trace data;
+ * based on it the decoder will make decision for setting
+ * sample's PID as context_id or VMID.
+ */
+ pid_fmt = perf_pmu__format_bits(&cs_etm_pmu->format, "pid");
+ if (!pid_fmt)
+ pid_fmt = 1ULL << ETM_OPT_CTXTID;
+ info->priv[*offset + CS_ETMV4_PID_FMT] = pid_fmt;
+
/* How much space was used */
increment = CS_ETMV4_PRIV_MAX;
} else {
@@ -658,6 +669,16 @@ static void cs_etm_get_metadata(int cpu, u32 *offset,
cs_etm_get_ro(cs_etm_pmu, cpu,
metadata_etmv3_ro[CS_ETM_ETMIDR]);
+ /*
+ * The PID format will be used when decode the trace data;
+ * based on it the decoder will make decision for setting
+ * sample's PID as context_id or VMID.
+ */
+ pid_fmt = perf_pmu__format_bits(&cs_etm_pmu->format, "pid");
+ if (!pid_fmt)
+ pid_fmt = 1ULL << ETM_OPT_CTXTID;
+ info->priv[*offset + CS_ETM_PID_FMT] = pid_fmt;
+
/* How much space was used */
increment = CS_ETM_PRIV_MAX;
}
diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c
index 5e284725dceb..763085db29ae 100644
--- a/tools/perf/util/cs-etm.c
+++ b/tools/perf/util/cs-etm.c
@@ -2447,6 +2447,7 @@ static const char * const cs_etm_priv_fmts[] = {
[CS_ETM_ETMTRACEIDR] = " ETMTRACEIDR %llx\n",
[CS_ETM_ETMCCER] = " ETMCCER %llx\n",
[CS_ETM_ETMIDR] = " ETMIDR %llx\n",
+ [CS_ETM_PID_FMT] = " PID Format %llx\n",
};
static const char * const cs_etmv4_priv_fmts[] = {
@@ -2459,6 +2460,7 @@ static const char * const cs_etmv4_priv_fmts[] = {
[CS_ETMV4_TRCIDR2] = " TRCIDR2 %llx\n",
[CS_ETMV4_TRCIDR8] = " TRCIDR8 %llx\n",
[CS_ETMV4_TRCAUTHSTATUS] = " TRCAUTHSTATUS %llx\n",
+ [CS_ETMV4_PID_FMT] = " PID Format %llx\n",
};
static void cs_etm__print_auxtrace_info(__u64 *val, int num)
diff --git a/tools/perf/util/cs-etm.h b/tools/perf/util/cs-etm.h
index 4ad925d6d799..8cbbea6100a1 100644
--- a/tools/perf/util/cs-etm.h
+++ b/tools/perf/util/cs-etm.h
@@ -38,6 +38,7 @@ enum {
/* RO, taken from sysFS */
CS_ETM_ETMCCER,
CS_ETM_ETMIDR,
+ CS_ETM_PID_FMT,
CS_ETM_PRIV_MAX,
};
@@ -52,6 +53,7 @@ enum {
CS_ETMV4_TRCIDR2,
CS_ETMV4_TRCIDR8,
CS_ETMV4_TRCAUTHSTATUS,
+ CS_ETMV4_PID_FMT,
CS_ETMV4_PRIV_MAX,
};
--
2.25.1
Hi Leo,
On 1/9/21 7:44 AM, Leo Yan wrote:
> It's possible for CoreSight to trace PID in either CONTEXTIDR_EL1 or
> CONTEXTIDR_EL2, the PID format info is used to distinguish the PID
> is traced in which register.
>
> This patch saves PID format into the metadata when record.
The patch looks good to me. One minor suggestion below
>
> Signed-off-by: Leo Yan <[email protected]>
> ---
> tools/perf/arch/arm/util/cs-etm.c | 21 +++++++++++++++++++++
> tools/perf/util/cs-etm.c | 2 ++
> tools/perf/util/cs-etm.h | 2 ++
> 3 files changed, 25 insertions(+)
>
> diff --git a/tools/perf/arch/arm/util/cs-etm.c b/tools/perf/arch/arm/util/cs-etm.c
> index fad7b6e13ccc..ee78df3b1b07 100644
> --- a/tools/perf/arch/arm/util/cs-etm.c
> +++ b/tools/perf/arch/arm/util/cs-etm.c
> @@ -613,6 +613,7 @@ static void cs_etm_get_metadata(int cpu, u32 *offset,
> struct cs_etm_recording *ptr =
> container_of(itr, struct cs_etm_recording, itr);
> struct perf_pmu *cs_etm_pmu = ptr->cs_etm_pmu;
> + u64 pid_fmt;
>
> /* first see what kind of tracer this cpu is affined to */
> if (cs_etm_is_etmv4(itr, cpu)) {
> @@ -641,6 +642,16 @@ static void cs_etm_get_metadata(int cpu, u32 *offset,
> metadata_etmv4_ro
> [CS_ETMV4_TRCAUTHSTATUS]);
>
> + /*
> + * The PID format will be used when decode the trace data;
> + * based on it the decoder will make decision for setting
> + * sample's PID as context_id or VMID.
> + */
> + pid_fmt = perf_pmu__format_bits(&cs_etm_pmu->format, "pid");
> + if (!pid_fmt)
> + pid_fmt = 1ULL << ETM_OPT_CTXTID;
> + info->priv[*offset + CS_ETMV4_PID_FMT] = pid_fmt;
> +
Given we do this same step twice here in this function and also in patch 2.
I am wondering if this could be made into a small helper function ?
static u64 cs_etm_pmu_format_pid(cs_etm_pm)
{
pid_fmt = perf_pmu__format_bits(&cs_etm_pmu->format, "pid");
/*
* An older kernel doesn't expose this, so fall back to using
* CTXTID.
*/
if (!pid_fmt)
pid_fmt = 1ULL << ETM_OPT_CTXTID;
return pid_fmt;
}
Suzuki
On Mon, Jan 11, 2021 at 09:45:12AM +0000, Suzuki Kuruppassery Poulose wrote:
> Hi Leo,
>
> On 1/9/21 7:44 AM, Leo Yan wrote:
> > It's possible for CoreSight to trace PID in either CONTEXTIDR_EL1 or
> > CONTEXTIDR_EL2, the PID format info is used to distinguish the PID
> > is traced in which register.
> >
> > This patch saves PID format into the metadata when record.
>
> The patch looks good to me. One minor suggestion below
>
> >
> > Signed-off-by: Leo Yan <[email protected]>
> > ---
> > tools/perf/arch/arm/util/cs-etm.c | 21 +++++++++++++++++++++
> > tools/perf/util/cs-etm.c | 2 ++
> > tools/perf/util/cs-etm.h | 2 ++
> > 3 files changed, 25 insertions(+)
> >
> > diff --git a/tools/perf/arch/arm/util/cs-etm.c b/tools/perf/arch/arm/util/cs-etm.c
> > index fad7b6e13ccc..ee78df3b1b07 100644
> > --- a/tools/perf/arch/arm/util/cs-etm.c
> > +++ b/tools/perf/arch/arm/util/cs-etm.c
> > @@ -613,6 +613,7 @@ static void cs_etm_get_metadata(int cpu, u32 *offset,
> > struct cs_etm_recording *ptr =
> > container_of(itr, struct cs_etm_recording, itr);
> > struct perf_pmu *cs_etm_pmu = ptr->cs_etm_pmu;
> > + u64 pid_fmt;
> > /* first see what kind of tracer this cpu is affined to */
> > if (cs_etm_is_etmv4(itr, cpu)) {
> > @@ -641,6 +642,16 @@ static void cs_etm_get_metadata(int cpu, u32 *offset,
> > metadata_etmv4_ro
> > [CS_ETMV4_TRCAUTHSTATUS]);
> > + /*
> > + * The PID format will be used when decode the trace data;
> > + * based on it the decoder will make decision for setting
> > + * sample's PID as context_id or VMID.
> > + */
> > + pid_fmt = perf_pmu__format_bits(&cs_etm_pmu->format, "pid");
> > + if (!pid_fmt)
> > + pid_fmt = 1ULL << ETM_OPT_CTXTID;
> > + info->priv[*offset + CS_ETMV4_PID_FMT] = pid_fmt;
> > +
>
> Given we do this same step twice here in this function and also in patch 2.
> I am wondering if this could be made into a small helper function ?
>
> static u64 cs_etm_pmu_format_pid(cs_etm_pm)
> {
> pid_fmt = perf_pmu__format_bits(&cs_etm_pmu->format, "pid");
> /*
> * An older kernel doesn't expose this, so fall back to using
> * CTXTID.
> */
> if (!pid_fmt)
> pid_fmt = 1ULL << ETM_OPT_CTXTID;
> return pid_fmt;
> }
Agreed; will follow up this suggestion.
Thanks,
Leo