On 2/4/21 4:00 AM, Leo Yan wrote:
On Tue, Feb 02, 2021 at 11:29:47PM +0000, Suzuki Kuruppassery Poulose wrote:
On 2/2/21 4:38 PM, Leo Yan wrote:
From: Suzuki K Poulose suzuki.poulose@arm.com
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.
Cc: Mike Leach mike.leach@linaro.org Cc: Mathieu Poirier mathieu.poirier@linaro.org Cc: Al Grant al.grant@arm.com Co-developed-by: Leo Yan leo.yan@linaro.org Signed-off-by: Suzuki K Poulose suzuki.poulose@arm.com Signed-off-by: Leo Yan leo.yan@linaro.org
.../perf/util/cs-etm-decoder/cs-etm-decoder.c | 32 ++++++++++++++++--- 1 file changed, 28 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..fb2a163ff74e 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 +492,36 @@ 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;
- u64 pid_fmt;
- int ret;
- /* Ignore PE_CONTEXT packets that don't have a valid contextID */
- if (!elem->context.ctxt_id_valid)
- ret = cs_etm__get_pid_fmt(trace_chan_id, &pid_fmt);
- if (ret)
Is this something we can cache in this function ? e.g, static u64 pid_fmt;
if (!pid_pfmt) ret = cs_etm__get_pid_fmt(trace_chan_id, &pid_fmt);
As all the ETMs will be running at the same exception level.
Sorry that I let you repeated your comments again.
To be honest, I considered this after read your comment in the previous series, but I thought it's possible that multiple CPUs have different PID format, especially for big.LITTLE arch. After read your suggestion again, I think my concern is not valid, even for big.LITTLE, all CPUs should run on the same kernel exception level.
So will follow up your suggestion to cache "pid_fmt".
No problem.
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) | BIT(ETM_OPT_CTXTID):
I would rather fix the cs_etm__get_pid_fmt() to return either of these as commented. i.e, ETM_OPT_CTXTID or ETM_OPT_CTXTID2. Thus we don't need the this case.
I explained why I set both bits for ETM_OPT_CTXTID and ETM_OPT_CTXTID2 in the patch 05/07. Could you take a look for it?
I have responded to the comment in the patch.
With the above two addressed:
Reviewed-by: Suzuki K Poulose suzuki.poulose@arm.com
Thanks Suzuki