| From 8e1488a46dcf73b1f1916d95421e303dbf773fb4 Mon Sep 17 00:00:00 2001 |
| From: Suzuki K Poulose <suzuki.poulose@arm.com> |
| Date: Wed, 24 Feb 2021 09:48:35 -0700 |
| Subject: [PATCH 5/5] perf cs-etm: Detect pid in VMID for kernel running at EL2 |
| |
| The PID of the task could be traced as VMID when the kernel is running |
| at EL2. Teach the decoder to look for VMID when the CONTEXTIDR (Arm32) |
| or CONTEXTIDR_EL1 (Arm64) is invalid but we have a valid VMID. |
| |
| Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> |
| Co-developed-by: Leo Yan <leo.yan@linaro.org> |
| Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org> |
| Cc: Al Grant <al.grant@arm.com> |
| Cc: Mike Leach <mike.leach@linaro.org> |
| Link: https://lore.kernel.org/r/20210213113220.292229-6-leo.yan@linaro.org |
| Link: https://lore.kernel.org/r/20210224164835.3497311-7-mathieu.poirier@linaro.org |
| Signed-off-by: Leo Yan <leo.yan@linaro.org> |
| Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
| --- |
| .../perf/util/cs-etm-decoder/cs-etm-decoder.c | 38 +++++++++++++++++-- |
| 1 file changed, 34 insertions(+), 4 deletions(-) |
| |
| diff --git a/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c b/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c |
| index 3f4bc4050477..4052c9ce6e2f 100644 |
| --- a/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c |
| +++ b/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c |
| @@ -6,6 +6,7 @@ |
| * Author: Mathieu Poirier <mathieu.poirier@linaro.org> |
| */ |
| |
| +#include <linux/coresight-pmu.h> |
| #include <linux/err.h> |
| #include <linux/list.h> |
| #include <linux/zalloc.h> |
| @@ -491,13 +492,42 @@ cs_etm_decoder__set_tid(struct cs_etm_queue *etmq, |
| const ocsd_generic_trace_elem *elem, |
| const uint8_t trace_chan_id) |
| { |
| - pid_t tid; |
| + pid_t tid = -1; |
| + static u64 pid_fmt; |
| + int ret; |
| |
| - /* Ignore PE_CONTEXT packets that don't have a valid contextID */ |
| - if (!elem->context.ctxt_id_valid) |
| + /* |
| + * As all the ETMs run at the same exception level, the system should |
| + * have the same PID format crossing CPUs. So cache the PID format |
| + * and reuse it for sequential decoding. |
| + */ |
| + if (!pid_fmt) { |
| + ret = cs_etm__get_pid_fmt(trace_chan_id, &pid_fmt); |
| + if (ret) |
| + return OCSD_RESP_FATAL_SYS_ERR; |
| + } |
| + |
| + /* |
| + * Process the PE_CONTEXT packets if we have a valid contextID or VMID. |
| + * If the kernel is running at EL2, the PID is traced in CONTEXTIDR_EL2 |
| + * as VMID, Bit ETM_OPT_CTXTID2 is set in this case. |
| + */ |
| + switch (pid_fmt) { |
| + case BIT(ETM_OPT_CTXTID): |
| + if (elem->context.ctxt_id_valid) |
| + tid = elem->context.context_id; |
| + break; |
| + case BIT(ETM_OPT_CTXTID2): |
| + if (elem->context.vmid_valid) |
| + tid = elem->context.vmid; |
| + break; |
| + default: |
| + break; |
| + } |
| + |
| + if (tid == -1) |
| return OCSD_RESP_CONT; |
| |
| - tid = elem->context.context_id; |
| if (cs_etm__etmq_set_tid(etmq, tid, trace_chan_id)) |
| return OCSD_RESP_FATAL_SYS_ERR; |
| |
| -- |
| 2.32.0.rc1.229.g3e70b5a671-goog |
| |