1 files changed, 264 insertions, 30 deletions

diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 3bcb9df93342..1d07f800a9ce 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -10,7 +10,9 @@
 #include <linux/module.h>
 #include <linux/ctype.h>
 
-#include "trace_events.h"
+#include "trace.h"
+
+#define TRACE_SYSTEM "TRACE_SYSTEM"
 
 #define events_for_each(event)                                          \
         for (event = __start_ftrace_events;                             \
@@ -42,35 +44,87 @@ static void ftrace_clear_events(void)
         }
 }
 
+static void ftrace_event_enable_disable(struct ftrace_event_call *call,
+                                        int enable)
+{
+
+        switch (enable) {
+        case 0:
+                if (call->enabled) {
+                        call->enabled = 0;
+                        call->unregfunc();
+                }
+                if (call->raw_enabled) {
+                        call->raw_enabled = 0;
+                        call->raw_unreg();
+                }
+                break;
+        case 1:
+                if (!call->enabled &&
+                    (call->type & TRACE_EVENT_TYPE_PRINTF)) {
+                        call->enabled = 1;
+                        call->regfunc();
+                }
+                if (!call->raw_enabled &&
+                    (call->type & TRACE_EVENT_TYPE_RAW)) {
+                        call->raw_enabled = 1;
+                        call->raw_reg();
+                }
+                break;
+        }
+}
+
 static int ftrace_set_clr_event(char *buf, int set)
 {
         struct ftrace_event_call *call = __start_ftrace_events;
-
+        char *event = NULL, *sub = NULL, *match;
+        int ret = -EINVAL;
+
+        /*
+         * The buf format can be <subsystem>:<event-name>
+         *  *:<event-name> means any event by that name.
+         *  :<event-name> is the same.
+         *
+         *  <subsystem>:* means all events in that subsystem
+         *  <subsystem>: means the same.
+         *
+         *  <name> (no ':') means all events in a subsystem with
+         *  the name <name> or any event that matches <name>
+         */
+
+        match = strsep(&buf, ":");
+        if (buf) {
+                sub = match;
+                event = buf;
+                match = NULL;
+
+                if (!strlen(sub) || strcmp(sub, "*") == 0)
+                        sub = NULL;
+                if (!strlen(event) || strcmp(event, "*") == 0)
+                        event = NULL;
+        }
 
         events_for_each(call) {
 
                 if (!call->name)
                         continue;
 
-                if (strcmp(buf, call->name) != 0)
+                if (match &&
+                    strcmp(match, call->name) != 0 &&
+                    strcmp(match, call->system) != 0)
                         continue;
 
-                if (set) {
-                        /* Already set? */
-                        if (call->enabled)
-                                return 0;
-                        call->enabled = 1;
-                        call->regfunc();
-                } else {
-                        /* Already cleared? */
-                        if (!call->enabled)
-                                return 0;
-                        call->enabled = 0;
-                        call->unregfunc();
-                }
-                return 0;
+                if (sub && strcmp(sub, call->system) != 0)
+                        continue;
+
+                if (event && strcmp(event, call->name) != 0)
+                        continue;
+
+                ftrace_event_enable_disable(call, set);
+
+                ret = 0;
         }
-        return -EINVAL;
+        return ret;
 }
 
 /* 128 should be much more than enough */
@@ -200,6 +254,8 @@ static int t_show(struct seq_file *m, void *v)
 {
         struct ftrace_event_call *call = v;
 
+        if (strcmp(call->system, TRACE_SYSTEM) != 0)
+                seq_printf(m, "%s:", call->system);
         seq_printf(m, "%s\n", call->name);
 
         return 0;
@@ -236,7 +292,7 @@ event_enable_read(struct file *filp, char __user *ubuf, size_t cnt,
         struct ftrace_event_call *call = filp->private_data;
         char *buf;
 
-        if (call->enabled)
+        if (call->enabled || call->raw_enabled)
                 buf = "1\n";
         else
                 buf = "0\n";
@@ -267,18 +323,8 @@ event_enable_write(struct file *filp, const char __user *ubuf, size_t cnt,
 
         switch (val) {
         case 0:
-                if (!call->enabled)
-                        break;
-
-                call->enabled = 0;
-                call->unregfunc();
-                break;
         case 1:
-                if (call->enabled)
-                        break;
-
-                call->enabled = 1;
-                call->regfunc();
+                ftrace_event_enable_disable(call, val);
                 break;
 
         default:
@@ -290,6 +336,107 @@ event_enable_write(struct file *filp, const char __user *ubuf, size_t cnt,
         return cnt;
 }
 
+static ssize_t
+event_type_read(struct file *filp, char __user *ubuf, size_t cnt,
+                loff_t *ppos)
+{
+        struct ftrace_event_call *call = filp->private_data;
+        char buf[16];
+        int r = 0;
+
+        if (call->type & TRACE_EVENT_TYPE_PRINTF)
+                r += sprintf(buf, "printf\n");
+
+        if (call->type & TRACE_EVENT_TYPE_RAW)
+                r += sprintf(buf+r, "raw\n");
+
+        return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
+}
+
+static ssize_t
+event_type_write(struct file *filp, const char __user *ubuf, size_t cnt,
+                 loff_t *ppos)
+{
+        struct ftrace_event_call *call = filp->private_data;
+        char buf[64];
+
+        /*
+         * If there's only one type, we can't change it.
+         * And currently we always have printf type, and we
+         * may or may not have raw type.
+         *
+         * This is a redundant check, the file should be read
+         * only if this is the case anyway.
+         */
+
+        if (!call->raw_init)
+                return -EPERM;
+
+        if (cnt >= sizeof(buf))
+                return -EINVAL;
+
+        if (copy_from_user(&buf, ubuf, cnt))
+                return -EFAULT;
+
+        buf[cnt] = 0;
+
+        if (!strncmp(buf, "printf", 6) &&
+            (!buf[6] || isspace(buf[6]))) {
+
+                call->type = TRACE_EVENT_TYPE_PRINTF;
+
+                /*
+                 * If raw enabled, the disable it and enable
+                 * printf type.
+                 */
+                if (call->raw_enabled) {
+                        call->raw_enabled = 0;
+                        call->raw_unreg();
+
+                        call->enabled = 1;
+                        call->regfunc();
+                }
+
+        } else if (!strncmp(buf, "raw", 3) &&
+            (!buf[3] || isspace(buf[3]))) {
+
+                call->type = TRACE_EVENT_TYPE_RAW;
+
+                /*
+                 * If printf enabled, the disable it and enable
+                 * raw type.
+                 */
+                if (call->enabled) {
+                        call->enabled = 0;
+                        call->unregfunc();
+
+                        call->raw_enabled = 1;
+                        call->raw_reg();
+                }
+        } else
+                return -EINVAL;
+
+        *ppos += cnt;
+
+        return cnt;
+}
+
+static ssize_t
+event_available_types_read(struct file *filp, char __user *ubuf, size_t cnt,
+                           loff_t *ppos)
+{
+        struct ftrace_event_call *call = filp->private_data;
+        char buf[16];
+        int r = 0;
+
+        r += sprintf(buf, "printf\n");
+
+        if (call->raw_init)
+                r += sprintf(buf+r, "raw\n");
+
+        return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
+}
+
 static const struct seq_operations show_event_seq_ops = {
         .start = t_start,
         .next = t_next,
@@ -325,6 +472,17 @@ static const struct file_operations ftrace_enable_fops = {
         .write = event_enable_write,
 };
 
+static const struct file_operations ftrace_type_fops = {
+        .open = tracing_open_generic,
+        .read = event_type_read,
+        .write = event_type_write,
+};
+
+static const struct file_operations ftrace_available_types_fops = {
+        .open = tracing_open_generic,
+        .read = event_available_types_read,
+};
+
 static struct dentry *event_trace_events_dir(void)
 {
         static struct dentry *d_tracer;
@@ -345,10 +503,71 @@ static struct dentry *event_trace_events_dir(void)
         return d_events;
 }
 
+struct event_subsystem {
+        struct list_head        list;
+        const char              *name;
+        struct dentry           *entry;
+};
+
+static LIST_HEAD(event_subsystems);
+
+static struct dentry *
+event_subsystem_dir(const char *name, struct dentry *d_events)
+{
+        struct event_subsystem *system;
+
+        /* First see if we did not already create this dir */
+        list_for_each_entry(system, &event_subsystems, list) {
+                if (strcmp(system->name, name) == 0)
+                        return system->entry;
+        }
+
+        /* need to create new entry */
+        system = kmalloc(sizeof(*system), GFP_KERNEL);
+        if (!system) {
+                pr_warning("No memory to create event subsystem %s\n",
+                           name);
+                return d_events;
+        }
+
+        system->entry = debugfs_create_dir(name, d_events);
+        if (!system->entry) {
+                pr_warning("Could not create event subsystem %s\n",
+                           name);
+                kfree(system);
+                return d_events;
+        }
+
+        system->name = name;
+        list_add(&system->list, &event_subsystems);
+
+        return system->entry;
+}
+
 static int
 event_create_dir(struct ftrace_event_call *call, struct dentry *d_events)
 {
         struct dentry *entry;
+        int ret;
+
+        /*
+         * If the trace point header did not define TRACE_SYSTEM
+         * then the system would be called "TRACE_SYSTEM".
+         */
+        if (strcmp(call->system, "TRACE_SYSTEM") != 0)
+                d_events = event_subsystem_dir(call->system, d_events);
+
+        if (call->raw_init) {
+                ret = call->raw_init();
+                if (ret < 0) {
+                        pr_warning("Could not initialize trace point"
+                                   " events/%s\n", call->name);
+                        return ret;
+                }
+        }
+
+        /* default the output to printf */
+        call->type = TRACE_EVENT_TYPE_PRINTF;
 
         call->dir = debugfs_create_dir(call->name, d_events);
         if (!call->dir) {
@@ -363,6 +582,21 @@ event_create_dir(struct ftrace_event_call *call, struct dentry *d_events)
                 pr_warning("Could not create debugfs "
                            "'%s/enable' entry\n", call->name);
 
+        /* Only let type be writable, if we can change it */
+        entry = debugfs_create_file("type",
+                                    call->raw_init ? 0644 : 0444,
+                                    call->dir, call,
+                                    &ftrace_type_fops);
+        if (!entry)
+                pr_warning("Could not create debugfs "
+                           "'%s/type' entry\n", call->name);
+
+        entry = debugfs_create_file("available_types", 0444, call->dir, call,
+                                    &ftrace_available_types_fops);
+        if (!entry)
+                pr_warning("Could not create debugfs "
+                           "'%s/type' available_types\n", call->name);
+
         return 0;
 }