diff options
Diffstat (limited to 'samples/tracepoints')
| -rw-r--r-- | samples/tracepoints/Makefile | 6 | ||||
| -rw-r--r-- | samples/tracepoints/tp-samples-trace.h | 11 | ||||
| -rw-r--r-- | samples/tracepoints/tracepoint-probe-sample.c | 57 | ||||
| -rw-r--r-- | samples/tracepoints/tracepoint-probe-sample2.c | 44 | ||||
| -rw-r--r-- | samples/tracepoints/tracepoint-sample.c | 56 |
5 files changed, 174 insertions, 0 deletions
diff --git a/samples/tracepoints/Makefile b/samples/tracepoints/Makefile new file mode 100644 index 00000000..36479ad9 --- /dev/null +++ b/samples/tracepoints/Makefile @@ -0,0 +1,6 @@ +# builds the tracepoint example kernel modules; +# then to use one (as root): insmod <module_name.ko> + +obj-$(CONFIG_SAMPLE_TRACEPOINTS) += tracepoint-sample.o +obj-$(CONFIG_SAMPLE_TRACEPOINTS) += tracepoint-probe-sample.o +obj-$(CONFIG_SAMPLE_TRACEPOINTS) += tracepoint-probe-sample2.o diff --git a/samples/tracepoints/tp-samples-trace.h b/samples/tracepoints/tp-samples-trace.h new file mode 100644 index 00000000..4d46be96 --- /dev/null +++ b/samples/tracepoints/tp-samples-trace.h @@ -0,0 +1,11 @@ +#ifndef _TP_SAMPLES_TRACE_H +#define _TP_SAMPLES_TRACE_H + +#include <linux/proc_fs.h> /* for struct inode and struct file */ +#include <linux/tracepoint.h> + +DECLARE_TRACE(subsys_event, + TP_PROTO(struct inode *inode, struct file *file), + TP_ARGS(inode, file)); +DECLARE_TRACE_NOARGS(subsys_eventb); +#endif diff --git a/samples/tracepoints/tracepoint-probe-sample.c b/samples/tracepoints/tracepoint-probe-sample.c new file mode 100644 index 00000000..744c0b96 --- /dev/null +++ b/samples/tracepoints/tracepoint-probe-sample.c @@ -0,0 +1,57 @@ +/* + * tracepoint-probe-sample.c + * + * sample tracepoint probes. + */ + +#include <linux/module.h> +#include <linux/file.h> +#include <linux/dcache.h> +#include "tp-samples-trace.h" + +/* + * Here the caller only guarantees locking for struct file and struct inode. + * Locking must therefore be done in the probe to use the dentry. + */ +static void probe_subsys_event(void *ignore, + struct inode *inode, struct file *file) +{ + path_get(&file->f_path); + dget(file->f_path.dentry); + printk(KERN_INFO "Event is encountered with filename %s\n", + file->f_path.dentry->d_name.name); + dput(file->f_path.dentry); + path_put(&file->f_path); +} + +static void probe_subsys_eventb(void *ignore) +{ + printk(KERN_INFO "Event B is encountered\n"); +} + +static int __init tp_sample_trace_init(void) +{ + int ret; + + ret = register_trace_subsys_event(probe_subsys_event, NULL); + WARN_ON(ret); + ret = register_trace_subsys_eventb(probe_subsys_eventb, NULL); + WARN_ON(ret); + + return 0; +} + +module_init(tp_sample_trace_init); + +static void __exit tp_sample_trace_exit(void) +{ + unregister_trace_subsys_eventb(probe_subsys_eventb, NULL); + unregister_trace_subsys_event(probe_subsys_event, NULL); + tracepoint_synchronize_unregister(); +} + +module_exit(tp_sample_trace_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Mathieu Desnoyers"); +MODULE_DESCRIPTION("Tracepoint Probes Samples"); diff --git a/samples/tracepoints/tracepoint-probe-sample2.c b/samples/tracepoints/tracepoint-probe-sample2.c new file mode 100644 index 00000000..9fcf990e --- /dev/null +++ b/samples/tracepoints/tracepoint-probe-sample2.c @@ -0,0 +1,44 @@ +/* + * tracepoint-probe-sample2.c + * + * 2nd sample tracepoint probes. + */ + +#include <linux/module.h> +#include <linux/fs.h> +#include "tp-samples-trace.h" + +/* + * Here the caller only guarantees locking for struct file and struct inode. + * Locking must therefore be done in the probe to use the dentry. + */ +static void probe_subsys_event(void *ignore, + struct inode *inode, struct file *file) +{ + printk(KERN_INFO "Event is encountered with inode number %lu\n", + inode->i_ino); +} + +static int __init tp_sample_trace_init(void) +{ + int ret; + + ret = register_trace_subsys_event(probe_subsys_event, NULL); + WARN_ON(ret); + + return 0; +} + +module_init(tp_sample_trace_init); + +static void __exit tp_sample_trace_exit(void) +{ + unregister_trace_subsys_event(probe_subsys_event, NULL); + tracepoint_synchronize_unregister(); +} + +module_exit(tp_sample_trace_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Mathieu Desnoyers"); +MODULE_DESCRIPTION("Tracepoint Probes Samples"); diff --git a/samples/tracepoints/tracepoint-sample.c b/samples/tracepoints/tracepoint-sample.c new file mode 100644 index 00000000..26fab33f --- /dev/null +++ b/samples/tracepoints/tracepoint-sample.c @@ -0,0 +1,56 @@ +/* tracepoint-sample.c + * + * Executes a tracepoint when /proc/tracepoint-sample is opened. + * + * (C) Copyright 2007 Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> + * + * This file is released under the GPLv2. + * See the file COPYING for more details. + */ + +#include <linux/module.h> +#include <linux/sched.h> +#include <linux/proc_fs.h> +#include "tp-samples-trace.h" + +DEFINE_TRACE(subsys_event); +DEFINE_TRACE(subsys_eventb); + +struct proc_dir_entry *pentry_sample; + +static int my_open(struct inode *inode, struct file *file) +{ + int i; + + trace_subsys_event(inode, file); + for (i = 0; i < 10; i++) + trace_subsys_eventb(); + return -EPERM; +} + +static const struct file_operations mark_ops = { + .open = my_open, +}; + +static int __init sample_init(void) +{ + printk(KERN_ALERT "sample init\n"); + pentry_sample = proc_create("tracepoint-sample", 0444, NULL, + &mark_ops); + if (!pentry_sample) + return -EPERM; + return 0; +} + +static void __exit sample_exit(void) +{ + printk(KERN_ALERT "sample exit\n"); + remove_proc_entry("tracepoint-sample", NULL); +} + +module_init(sample_init) +module_exit(sample_exit) + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Mathieu Desnoyers"); +MODULE_DESCRIPTION("Tracepoint sample"); |