linux-kernel - [PATCH v2 05/17] trace: energy_model: Add trace event for EM runtime modifications

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20230512095743.3393563-6-lukasz.luba@arm.com>
Date:   Fri, 12 May 2023 10:57:31 +0100
From:   Lukasz Luba <lukasz.luba@....com>
To:     linux-kernel@...r.kernel.org, linux-pm@...r.kernel.org,
        rafael@...nel.org
Cc:     lukasz.luba@....com, dietmar.eggemann@....com, rui.zhang@...el.com,
        amit.kucheria@...durent.com, amit.kachhap@...il.com,
        daniel.lezcano@...aro.org, viresh.kumar@...aro.org,
        len.brown@...el.com, pavel@....cz, Pierre.Gondois@....com,
        ionela.voinescu@....com, rostedt@...dmis.org, mhiramat@...nel.org
Subject: [PATCH v2 05/17] trace: energy_model: Add trace event for EM runtime modifications

The Energy Model (EM) supports runtime modifications. Track the changes
in order to do post-processing analysis. Don't use arrays in the trace
event, since they are not properly supported by the tools. Instead use
simple "unroll" with emitting the trace event for each EM array entry
with proper ID information. The older debugging mechanism which was
the simple debugfs which dumping the EM content won't be sufficient for
the modifiable EM purpose. This trace event mechanism would address the
needs.

Signed-off-by: Lukasz Luba <lukasz.luba@....com>
---
 include/trace/events/energy_model.h | 46 +++++++++++++++++++++++++++++
 kernel/power/energy_model.c         |  3 ++
 2 files changed, 49 insertions(+)
 create mode 100644 include/trace/events/energy_model.h

diff --git a/include/trace/events/energy_model.h b/include/trace/events/energy_model.h
new file mode 100644
index 000000000000..f70babeb5dde
--- /dev/null
+++ b/include/trace/events/energy_model.h
@@ -0,0 +1,46 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM energy_model
+
+#if !defined(_TRACE_ENERGY_MODEL_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_ENERGY_MODEL_H
+
+#include <linux/tracepoint.h>
+
+TRACE_EVENT(em_perf_state,
+	TP_PROTO(const char *dev_name, int nr_perf_states, int state,
+		 unsigned long ps_frequency, unsigned long ps_power,
+		 unsigned long ps_cost, unsigned long ps_flags),
+
+	TP_ARGS(dev_name, nr_perf_states, state, ps_frequency, ps_power, ps_cost,
+		ps_flags),
+
+	TP_STRUCT__entry(
+		__string(name, dev_name)
+		__field(int, num_states)
+		__field(int, state)
+		__field(unsigned long, frequency)
+		__field(unsigned long, power)
+		__field(unsigned long, cost)
+		__field(unsigned long, flags)
+	),
+
+	TP_fast_assign(
+		__assign_str(name, dev_name);
+		__entry->num_states = nr_perf_states;
+		__entry->state = state;
+		__entry->frequency = ps_frequency;
+		__entry->power = ps_power;
+		__entry->cost = ps_cost;
+		__entry->flags = ps_flags;
+	),
+
+	TP_printk("dev_name=%s nr_perf_states=%d state=%d frequency=%lu power=%lu cost=%lu flags=%lu",
+		__get_str(name), __entry->num_states, __entry->state,
+		__entry->frequency, __entry->power, __entry->cost,
+		__entry->flags)
+);
+#endif /* _TRACE_ENERGY_MODEL_H */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>
diff --git a/kernel/power/energy_model.c b/kernel/power/energy_model.c
index fd1066dcf38b..61d349fec545 100644
--- a/kernel/power/energy_model.c
+++ b/kernel/power/energy_model.c
@@ -17,6 +17,9 @@
 #include <linux/sched/topology.h>
 #include <linux/slab.h>
 
+#define CREATE_TRACE_POINTS
+#include <trace/events/energy_model.h>
+
 /*
  * Mutex serializing the registrations of performance domains and letting
  * callbacks defined by drivers sleep.
-- 
2.25.1