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authorLinus Torvalds <torvalds@linux-foundation.org>2016-12-15 13:49:34 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2016-12-15 13:49:34 -0800
commit179a7ba6806805bd4cd7a5e4574b83353c5615ad (patch)
tree58855a59ba3bd66f947c3f9781cd44a7329c7d75 /drivers/hwtracing/stm
parent5e176d6973bdac04d9f298ca384c39f08eb084cb (diff)
parent3dbb16b87b57bb1088044ad2a0432e4769075002 (diff)
Merge tag 'trace-v4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing updates from Steven Rostedt: "This release has a few updates: - STM can hook into the function tracer - Function filtering now supports more advance glob matching - Ftrace selftests updates and added tests - Softirq tag in traces now show only softirqs - ARM nop added to non traced locations at compile time - New trace_marker_raw file that allows for binary input - Optimizations to the ring buffer - Removal of kmap in trace_marker - Wakeup and irqsoff tracers now adhere to the set_graph_notrace file - Other various fixes and clean ups" * tag 'trace-v4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (42 commits) selftests: ftrace: Shift down default message verbosity kprobes/trace: Fix kprobe selftest for newer gcc tracing/kprobes: Add a helper method to return number of probe hits tracing/rb: Init the CPU mask on allocation tracing: Use SOFTIRQ_OFFSET for softirq dectection for more accurate results tracing/fgraph: Have wakeup and irqsoff tracers ignore graph functions too fgraph: Handle a case where a tracer ignores set_graph_notrace tracing: Replace kmap with copy_from_user() in trace_marker writing ftrace/x86_32: Set ftrace_stub to weak to prevent gcc from using short jumps to it tracing: Allow benchmark to be enabled at early_initcall() tracing: Have system enable return error if one of the events fail tracing: Do not start benchmark on boot up tracing: Have the reg function allow to fail ring-buffer: Force rb_end_commit() and rb_set_commit_to_write() inline ring-buffer: Froce rb_update_write_stamp() to be inlined ring-buffer: Force inline of hotpath helper functions tracing: Make __buffer_unlock_commit() always_inline tracing: Make tracepoint_printk a static_key ring-buffer: Always inline rb_event_data() ring-buffer: Make rb_reserve_next_event() always inlined ...
Diffstat (limited to 'drivers/hwtracing/stm')
-rw-r--r--drivers/hwtracing/stm/Kconfig11
-rw-r--r--drivers/hwtracing/stm/Makefile2
-rw-r--r--drivers/hwtracing/stm/core.c7
-rw-r--r--drivers/hwtracing/stm/dummy_stm.c2
-rw-r--r--drivers/hwtracing/stm/ftrace.c87
5 files changed, 105 insertions, 4 deletions
diff --git a/drivers/hwtracing/stm/Kconfig b/drivers/hwtracing/stm/Kconfig
index 847a39b35307..723e2d90083d 100644
--- a/drivers/hwtracing/stm/Kconfig
+++ b/drivers/hwtracing/stm/Kconfig
@@ -39,4 +39,15 @@ config STM_SOURCE_HEARTBEAT
If you want to send heartbeat messages over STM devices,
say Y.
+config STM_SOURCE_FTRACE
+ tristate "Copy the output from kernel Ftrace to STM engine"
+ depends on FUNCTION_TRACER
+ help
+ This option can be used to copy the output from kernel Ftrace
+ to STM engine. Enabling this option will introduce a slight
+ timing effect.
+
+ If you want to send kernel Ftrace messages over STM devices,
+ say Y.
+
endif
diff --git a/drivers/hwtracing/stm/Makefile b/drivers/hwtracing/stm/Makefile
index a9ce3d487e57..3abd84ce13d4 100644
--- a/drivers/hwtracing/stm/Makefile
+++ b/drivers/hwtracing/stm/Makefile
@@ -6,6 +6,8 @@ obj-$(CONFIG_STM_DUMMY) += dummy_stm.o
obj-$(CONFIG_STM_SOURCE_CONSOLE) += stm_console.o
obj-$(CONFIG_STM_SOURCE_HEARTBEAT) += stm_heartbeat.o
+obj-$(CONFIG_STM_SOURCE_FTRACE) += stm_ftrace.o
stm_console-y := console.o
stm_heartbeat-y := heartbeat.o
+stm_ftrace-y := ftrace.o
diff --git a/drivers/hwtracing/stm/core.c b/drivers/hwtracing/stm/core.c
index a6ea387b5b00..0e731143f6a4 100644
--- a/drivers/hwtracing/stm/core.c
+++ b/drivers/hwtracing/stm/core.c
@@ -427,7 +427,7 @@ static int stm_file_assign(struct stm_file *stmf, char *id, unsigned int width)
return ret;
}
-static ssize_t stm_write(struct stm_data *data, unsigned int master,
+static ssize_t notrace stm_write(struct stm_data *data, unsigned int master,
unsigned int channel, const char *buf, size_t count)
{
unsigned int flags = STP_PACKET_TIMESTAMPED;
@@ -1123,8 +1123,9 @@ void stm_source_unregister_device(struct stm_source_data *data)
}
EXPORT_SYMBOL_GPL(stm_source_unregister_device);
-int stm_source_write(struct stm_source_data *data, unsigned int chan,
- const char *buf, size_t count)
+int notrace stm_source_write(struct stm_source_data *data,
+ unsigned int chan,
+ const char *buf, size_t count)
{
struct stm_source_device *src = data->src;
struct stm_device *stm;
diff --git a/drivers/hwtracing/stm/dummy_stm.c b/drivers/hwtracing/stm/dummy_stm.c
index a86612d989f9..c5f94ca31c4d 100644
--- a/drivers/hwtracing/stm/dummy_stm.c
+++ b/drivers/hwtracing/stm/dummy_stm.c
@@ -21,7 +21,7 @@
#include <linux/slab.h>
#include <linux/stm.h>
-static ssize_t
+static ssize_t notrace
dummy_stm_packet(struct stm_data *stm_data, unsigned int master,
unsigned int channel, unsigned int packet, unsigned int flags,
unsigned int size, const unsigned char *payload)
diff --git a/drivers/hwtracing/stm/ftrace.c b/drivers/hwtracing/stm/ftrace.c
new file mode 100644
index 000000000000..bd126a7c6da2
--- /dev/null
+++ b/drivers/hwtracing/stm/ftrace.c
@@ -0,0 +1,87 @@
+/*
+ * Simple kernel driver to link kernel Ftrace and an STM device
+ * Copyright (c) 2016, Linaro Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * STM Ftrace will be registered as a trace_export.
+ */
+
+#include <linux/module.h>
+#include <linux/stm.h>
+#include <linux/trace.h>
+
+#define STM_FTRACE_NR_CHANNELS 1
+#define STM_FTRACE_CHAN 0
+
+static int stm_ftrace_link(struct stm_source_data *data);
+static void stm_ftrace_unlink(struct stm_source_data *data);
+
+static struct stm_ftrace {
+ struct stm_source_data data;
+ struct trace_export ftrace;
+} stm_ftrace = {
+ .data = {
+ .name = "ftrace",
+ .nr_chans = STM_FTRACE_NR_CHANNELS,
+ .link = stm_ftrace_link,
+ .unlink = stm_ftrace_unlink,
+ },
+};
+
+/**
+ * stm_ftrace_write() - write data to STM via 'stm_ftrace' source
+ * @buf: buffer containing the data packet
+ * @len: length of the data packet
+ */
+static void notrace
+stm_ftrace_write(const void *buf, unsigned int len)
+{
+ stm_source_write(&stm_ftrace.data, STM_FTRACE_CHAN, buf, len);
+}
+
+static int stm_ftrace_link(struct stm_source_data *data)
+{
+ struct stm_ftrace *sf = container_of(data, struct stm_ftrace, data);
+
+ sf->ftrace.write = stm_ftrace_write;
+
+ return register_ftrace_export(&sf->ftrace);
+}
+
+static void stm_ftrace_unlink(struct stm_source_data *data)
+{
+ struct stm_ftrace *sf = container_of(data, struct stm_ftrace, data);
+
+ unregister_ftrace_export(&sf->ftrace);
+}
+
+static int __init stm_ftrace_init(void)
+{
+ int ret;
+
+ ret = stm_source_register_device(NULL, &stm_ftrace.data);
+ if (ret)
+ pr_err("Failed to register stm_source - ftrace.\n");
+
+ return ret;
+}
+
+static void __exit stm_ftrace_exit(void)
+{
+ stm_source_unregister_device(&stm_ftrace.data);
+}
+
+module_init(stm_ftrace_init);
+module_exit(stm_ftrace_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("stm_ftrace driver");
+MODULE_AUTHOR("Chunyan Zhang <zhang.chunyan@linaro.org>");