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-rw-r--r--samples/Kconfig9
-rw-r--r--samples/Makefile2
-rw-r--r--samples/firmware_class/firmware_sample_driver.c121
-rw-r--r--samples/firmware_class/firmware_sample_firmware_class.c204
-rw-r--r--samples/trace_events/Makefile14
-rw-r--r--samples/trace_events/trace-events-sample.c52
-rw-r--r--samples/trace_events/trace-events-sample.h134
7 files changed, 209 insertions, 327 deletions
diff --git a/samples/Kconfig b/samples/Kconfig
index 4b02f5a0e65..428b065ba69 100644
--- a/samples/Kconfig
+++ b/samples/Kconfig
@@ -19,8 +19,15 @@ config SAMPLE_TRACEPOINTS
help
This build tracepoints example modules.
+config SAMPLE_TRACE_EVENTS
+ tristate "Build trace_events examples -- loadable modules only"
+ depends on EVENT_TRACING && m
+ help
+ This build trace event example modules.
+
config SAMPLE_KOBJECT
- tristate "Build kobject examples"
+ tristate "Build kobject examples -- loadable modules only"
+ depends on m
help
This config option will allow you to build a number of
different kobject sample modules showing how to use kobjects,
diff --git a/samples/Makefile b/samples/Makefile
index 10eaca89fe1..13e4b470b53 100644
--- a/samples/Makefile
+++ b/samples/Makefile
@@ -1,3 +1,3 @@
# Makefile for Linux samples code
-obj-$(CONFIG_SAMPLES) += markers/ kobject/ kprobes/ tracepoints/
+obj-$(CONFIG_SAMPLES) += markers/ kobject/ kprobes/ tracepoints/ trace_events/
diff --git a/samples/firmware_class/firmware_sample_driver.c b/samples/firmware_class/firmware_sample_driver.c
deleted file mode 100644
index 219a2989660..00000000000
--- a/samples/firmware_class/firmware_sample_driver.c
+++ /dev/null
@@ -1,121 +0,0 @@
-/*
- * firmware_sample_driver.c -
- *
- * Copyright (c) 2003 Manuel Estrada Sainz
- *
- * Sample code on how to use request_firmware() from drivers.
- *
- */
-
-#include <linux/module.h>
-#include <linux/kernel.h>
-#include <linux/init.h>
-#include <linux/device.h>
-#include <linux/string.h>
-#include <linux/firmware.h>
-
-static struct device ghost_device = {
- .bus_id = "ghost0",
-};
-
-
-static void sample_firmware_load(char *firmware, int size)
-{
- u8 buf[size+1];
- memcpy(buf, firmware, size);
- buf[size] = '\0';
- printk(KERN_INFO "firmware_sample_driver: firmware: %s\n", buf);
-}
-
-static void sample_probe_default(void)
-{
- /* uses the default method to get the firmware */
- const struct firmware *fw_entry;
- int retval;
-
- printk(KERN_INFO "firmware_sample_driver: "
- "a ghost device got inserted :)\n");
-
- retval = request_firmware(&fw_entry, "sample_driver_fw", &ghost_device);
- if (retval) {
- printk(KERN_ERR
- "firmware_sample_driver: Firmware not available\n");
- return;
- }
-
- sample_firmware_load(fw_entry->data, fw_entry->size);
-
- release_firmware(fw_entry);
-
- /* finish setting up the device */
-}
-
-static void sample_probe_specific(void)
-{
- int retval;
- /* Uses some specific hotplug support to get the firmware from
- * userspace directly into the hardware, or via some sysfs file */
-
- /* NOTE: This currently doesn't work */
-
- printk(KERN_INFO "firmware_sample_driver: "
- "a ghost device got inserted :)\n");
-
- retval = request_firmware(NULL, "sample_driver_fw", &ghost_device);
- if (retval) {
- printk(KERN_ERR
- "firmware_sample_driver: Firmware load failed\n");
- return;
- }
-
- /* request_firmware blocks until userspace finished, so at
- * this point the firmware should be already in the device */
-
- /* finish setting up the device */
-}
-
-static void sample_probe_async_cont(const struct firmware *fw, void *context)
-{
- if (!fw) {
- printk(KERN_ERR
- "firmware_sample_driver: firmware load failed\n");
- return;
- }
-
- printk(KERN_INFO "firmware_sample_driver: device pointer \"%s\"\n",
- (char *)context);
- sample_firmware_load(fw->data, fw->size);
-}
-
-static void sample_probe_async(void)
-{
- /* Let's say that I can't sleep */
- int error;
- error = request_firmware_nowait(THIS_MODULE, FW_ACTION_NOHOTPLUG,
- "sample_driver_fw", &ghost_device,
- "my device pointer",
- sample_probe_async_cont);
- if (error)
- printk(KERN_ERR "firmware_sample_driver:"
- " request_firmware_nowait failed\n");
-}
-
-static int __init sample_init(void)
-{
- device_initialize(&ghost_device);
- /* since there is no real hardware insertion I just call the
- * sample probe functions here */
- sample_probe_specific();
- sample_probe_default();
- sample_probe_async();
- return 0;
-}
-
-static void __exit sample_exit(void)
-{
-}
-
-module_init(sample_init);
-module_exit(sample_exit);
-
-MODULE_LICENSE("GPL");
diff --git a/samples/firmware_class/firmware_sample_firmware_class.c b/samples/firmware_class/firmware_sample_firmware_class.c
deleted file mode 100644
index e6cf7a43a29..00000000000
--- a/samples/firmware_class/firmware_sample_firmware_class.c
+++ /dev/null
@@ -1,204 +0,0 @@
-/*
- * firmware_sample_firmware_class.c -
- *
- * Copyright (c) 2003 Manuel Estrada Sainz
- *
- * NOTE: This is just a probe of concept, if you think that your driver would
- * be well served by this mechanism please contact me first.
- *
- * DON'T USE THIS CODE AS IS
- *
- */
-
-#include <linux/device.h>
-#include <linux/module.h>
-#include <linux/init.h>
-#include <linux/timer.h>
-#include <linux/slab.h>
-#include <linux/string.h>
-#include <linux/firmware.h>
-
-
-MODULE_AUTHOR("Manuel Estrada Sainz");
-MODULE_DESCRIPTION("Hackish sample for using firmware class directly");
-MODULE_LICENSE("GPL");
-
-static inline struct class_device *to_class_dev(struct kobject *obj)
-{
- return container_of(obj, struct class_device, kobj);
-}
-
-static inline
-struct class_device_attribute *to_class_dev_attr(struct attribute *_attr)
-{
- return container_of(_attr, struct class_device_attribute, attr);
-}
-
-struct firmware_priv {
- char fw_id[FIRMWARE_NAME_MAX];
- s32 loading:2;
- u32 abort:1;
-};
-
-static ssize_t firmware_loading_show(struct class_device *class_dev, char *buf)
-{
- struct firmware_priv *fw_priv = class_get_devdata(class_dev);
- return sprintf(buf, "%d\n", fw_priv->loading);
-}
-
-static ssize_t firmware_loading_store(struct class_device *class_dev,
- const char *buf, size_t count)
-{
- struct firmware_priv *fw_priv = class_get_devdata(class_dev);
- int prev_loading = fw_priv->loading;
-
- fw_priv->loading = simple_strtol(buf, NULL, 10);
-
- switch (fw_priv->loading) {
- case -1:
- /* abort load an panic */
- break;
- case 1:
- /* setup load */
- break;
- case 0:
- if (prev_loading == 1) {
- /* finish load and get the device back to working
- * state */
- }
- break;
- }
-
- return count;
-}
-static CLASS_DEVICE_ATTR(loading, 0644,
- firmware_loading_show, firmware_loading_store);
-
-static ssize_t firmware_data_read(struct kobject *kobj,
- struct bin_attribute *bin_attr,
- char *buffer, loff_t offset, size_t count)
-{
- struct class_device *class_dev = to_class_dev(kobj);
- struct firmware_priv *fw_priv = class_get_devdata(class_dev);
-
- /* read from the devices firmware memory */
-
- return count;
-}
-static ssize_t firmware_data_write(struct kobject *kobj,
- struct bin_attribute *bin_attr,
- char *buffer, loff_t offset, size_t count)
-{
- struct class_device *class_dev = to_class_dev(kobj);
- struct firmware_priv *fw_priv = class_get_devdata(class_dev);
-
- /* write to the devices firmware memory */
-
- return count;
-}
-static struct bin_attribute firmware_attr_data = {
- .attr = {.name = "data", .mode = 0644},
- .size = 0,
- .read = firmware_data_read,
- .write = firmware_data_write,
-};
-static int fw_setup_class_device(struct class_device *class_dev,
- const char *fw_name,
- struct device *device)
-{
- int retval;
- struct firmware_priv *fw_priv;
-
- fw_priv = kzalloc(sizeof(struct firmware_priv), GFP_KERNEL);
- if (!fw_priv) {
- retval = -ENOMEM;
- goto out;
- }
-
- memset(class_dev, 0, sizeof(*class_dev));
-
- strncpy(fw_priv->fw_id, fw_name, FIRMWARE_NAME_MAX);
- fw_priv->fw_id[FIRMWARE_NAME_MAX-1] = '\0';
-
- strncpy(class_dev->class_id, device->bus_id, BUS_ID_SIZE);
- class_dev->class_id[BUS_ID_SIZE-1] = '\0';
- class_dev->dev = device;
-
- class_dev->class = &firmware_class;
- class_set_devdata(class_dev, fw_priv);
- retval = class_device_register(class_dev);
- if (retval) {
- printk(KERN_ERR "%s: class_device_register failed\n",
- __func__);
- goto error_free_fw_priv;
- }
-
- retval = sysfs_create_bin_file(&class_dev->kobj, &firmware_attr_data);
- if (retval) {
- printk(KERN_ERR "%s: sysfs_create_bin_file failed\n",
- __func__);
- goto error_unreg_class_dev;
- }
-
- retval = class_device_create_file(class_dev,
- &class_device_attr_loading);
- if (retval) {
- printk(KERN_ERR "%s: class_device_create_file failed\n",
- __func__);
- goto error_remove_data;
- }
-
- goto out;
-
-error_remove_data:
- sysfs_remove_bin_file(&class_dev->kobj, &firmware_attr_data);
-error_unreg_class_dev:
- class_device_unregister(class_dev);
-error_free_fw_priv:
- kfree(fw_priv);
-out:
- return retval;
-}
-static void fw_remove_class_device(struct class_device *class_dev)
-{
- struct firmware_priv *fw_priv = class_get_devdata(class_dev);
-
- class_device_remove_file(class_dev, &class_device_attr_loading);
- sysfs_remove_bin_file(&class_dev->kobj, &firmware_attr_data);
- class_device_unregister(class_dev);
-}
-
-static struct class_device *class_dev;
-
-static struct device my_device = {
- .bus_id = "my_dev0",
-};
-
-static int __init firmware_sample_init(void)
-{
- int error;
-
- device_initialize(&my_device);
- class_dev = kmalloc(sizeof(struct class_device), GFP_KERNEL);
- if (!class_dev)
- return -ENOMEM;
-
- error = fw_setup_class_device(class_dev, "my_firmware_image",
- &my_device);
- if (error) {
- kfree(class_dev);
- return error;
- }
- return 0;
-
-}
-static void __exit firmware_sample_exit(void)
-{
- struct firmware_priv *fw_priv = class_get_devdata(class_dev);
- fw_remove_class_device(class_dev);
- kfree(fw_priv);
- kfree(class_dev);
-}
-
-module_init(firmware_sample_init);
-module_exit(firmware_sample_exit);
diff --git a/samples/trace_events/Makefile b/samples/trace_events/Makefile
new file mode 100644
index 00000000000..0f8d92120c4
--- /dev/null
+++ b/samples/trace_events/Makefile
@@ -0,0 +1,14 @@
+# builds the trace events example kernel modules;
+# then to use one (as root): insmod <module_name.ko>
+
+# If you include a trace header outside of include/trace/events
+# then the file that does the #define CREATE_TRACE_POINTS must
+# have that tracer file in its main search path. This is because
+# define_trace.h will include it, and must be able to find it from
+# the include/trace directory.
+#
+# Here trace-events-sample.c does the CREATE_TRACE_POINTS.
+#
+CFLAGS_trace-events-sample.o := -I$(src)
+
+obj-$(CONFIG_SAMPLE_TRACE_EVENTS) += trace-events-sample.o
diff --git a/samples/trace_events/trace-events-sample.c b/samples/trace_events/trace-events-sample.c
new file mode 100644
index 00000000000..aabc4e97091
--- /dev/null
+++ b/samples/trace_events/trace-events-sample.c
@@ -0,0 +1,52 @@
+#include <linux/module.h>
+#include <linux/kthread.h>
+
+/*
+ * Any file that uses trace points, must include the header.
+ * But only one file, must include the header by defining
+ * CREATE_TRACE_POINTS first. This will make the C code that
+ * creates the handles for the trace points.
+ */
+#define CREATE_TRACE_POINTS
+#include "trace-events-sample.h"
+
+
+static void simple_thread_func(int cnt)
+{
+ set_current_state(TASK_INTERRUPTIBLE);
+ schedule_timeout(HZ);
+ trace_foo_bar("hello", cnt);
+}
+
+static int simple_thread(void *arg)
+{
+ int cnt = 0;
+
+ while (!kthread_should_stop())
+ simple_thread_func(cnt++);
+
+ return 0;
+}
+
+static struct task_struct *simple_tsk;
+
+static int __init trace_event_init(void)
+{
+ simple_tsk = kthread_run(simple_thread, NULL, "event-sample");
+ if (IS_ERR(simple_tsk))
+ return -1;
+
+ return 0;
+}
+
+static void __exit trace_event_exit(void)
+{
+ kthread_stop(simple_tsk);
+}
+
+module_init(trace_event_init);
+module_exit(trace_event_exit);
+
+MODULE_AUTHOR("Steven Rostedt");
+MODULE_DESCRIPTION("trace-events-sample");
+MODULE_LICENSE("GPL");
diff --git a/samples/trace_events/trace-events-sample.h b/samples/trace_events/trace-events-sample.h
new file mode 100644
index 00000000000..9977a756fb3
--- /dev/null
+++ b/samples/trace_events/trace-events-sample.h
@@ -0,0 +1,134 @@
+/*
+ * Notice that this file is not protected like a normal header.
+ * We also must allow for rereading of this file. The
+ *
+ * || defined(TRACE_HEADER_MULTI_READ)
+ *
+ * serves this purpose.
+ */
+#if !defined(_TRACE_EVENT_SAMPLE_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_EVENT_SAMPLE_H
+
+/*
+ * All trace headers should include tracepoint.h, until we finally
+ * make it into a standard header.
+ */
+#include <linux/tracepoint.h>
+
+/*
+ * If TRACE_SYSTEM is defined, that will be the directory created
+ * in the ftrace directory under /debugfs/tracing/events/<system>
+ *
+ * The define_trace.h below will also look for a file name of
+ * TRACE_SYSTEM.h where TRACE_SYSTEM is what is defined here.
+ * In this case, it would look for sample.h
+ *
+ * If the header name will be different than the system name
+ * (as in this case), then you can override the header name that
+ * define_trace.h will look up by defining TRACE_INCLUDE_FILE
+ *
+ * This file is called trace-events-sample.h but we want the system
+ * to be called "sample". Therefore we must define the name of this
+ * file:
+ *
+ * #define TRACE_INCLUDE_FILE trace-events-sample
+ *
+ * As we do an the bottom of this file.
+ */
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM sample
+
+/*
+ * The TRACE_EVENT macro is broken up into 5 parts.
+ *
+ * name: name of the trace point. This is also how to enable the tracepoint.
+ * A function called trace_foo_bar() will be created.
+ *
+ * proto: the prototype of the function trace_foo_bar()
+ * Here it is trace_foo_bar(char *foo, int bar).
+ *
+ * args: must match the arguments in the prototype.
+ * Here it is simply "foo, bar".
+ *
+ * struct: This defines the way the data will be stored in the ring buffer.
+ * There are currently two types of elements. __field and __array.
+ * a __field is broken up into (type, name). Where type can be any
+ * type but an array.
+ * For an array. there are three fields. (type, name, size). The
+ * type of elements in the array, the name of the field and the size
+ * of the array.
+ *
+ * __array( char, foo, 10) is the same as saying char foo[10].
+ *
+ * fast_assign: This is a C like function that is used to store the items
+ * into the ring buffer.
+ *
+ * printk: This is a way to print out the data in pretty print. This is
+ * useful if the system crashes and you are logging via a serial line,
+ * the data can be printed to the console using this "printk" method.
+ *
+ * Note, that for both the assign and the printk, __entry is the handler
+ * to the data structure in the ring buffer, and is defined by the
+ * TP_STRUCT__entry.
+ */
+TRACE_EVENT(foo_bar,
+
+ TP_PROTO(char *foo, int bar),
+
+ TP_ARGS(foo, bar),
+
+ TP_STRUCT__entry(
+ __array( char, foo, 10 )
+ __field( int, bar )
+ ),
+
+ TP_fast_assign(
+ strncpy(__entry->foo, foo, 10);
+ __entry->bar = bar;
+ ),
+
+ TP_printk("foo %s %d", __entry->foo, __entry->bar)
+);
+#endif
+
+/***** NOTICE! The #if protection ends here. *****/
+
+
+/*
+ * There are several ways I could have done this. If I left out the
+ * TRACE_INCLUDE_PATH, then it would default to the kernel source
+ * include/trace/events directory.
+ *
+ * I could specify a path from the define_trace.h file back to this
+ * file.
+ *
+ * #define TRACE_INCLUDE_PATH ../../samples/trace_events
+ *
+ * But the safest and easiest way to simply make it use the directory
+ * that the file is in is to add in the Makefile:
+ *
+ * CFLAGS_trace-events-sample.o := -I$(src)
+ *
+ * This will make sure the current path is part of the include
+ * structure for our file so that define_trace.h can find it.
+ *
+ * I could have made only the top level directory the include:
+ *
+ * CFLAGS_trace-events-sample.o := -I$(PWD)
+ *
+ * And then let the path to this directory be the TRACE_INCLUDE_PATH:
+ *
+ * #define TRACE_INCLUDE_PATH samples/trace_events
+ *
+ * But then if something defines "samples" or "trace_events" as a macro
+ * then we could risk that being converted too, and give us an unexpected
+ * result.
+ */
+#undef TRACE_INCLUDE_PATH
+#undef TRACE_INCLUDE_FILE
+#define TRACE_INCLUDE_PATH .
+/*
+ * TRACE_INCLUDE_FILE is not needed if the filename and TRACE_SYSTEM are equal
+ */
+#define TRACE_INCLUDE_FILE trace-events-sample
+#include <trace/define_trace.h>