diff options
| -rw-r--r-- | kernel/trace/trace.h | 7 | ||||
| -rw-r--r-- | kernel/trace/trace_events.c | 199 |
2 files changed, 181 insertions, 25 deletions
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index aa1ab0c..f6fa0b9 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -726,6 +726,12 @@ static inline void trace_branch_disable(void) } #endif /* CONFIG_BRANCH_TRACER */ +/* trace event type bit fields, not numeric */ +enum { + TRACE_EVENT_TYPE_PRINTF = 1, + TRACE_EVENT_TYPE_RAW = 2, +}; + struct ftrace_event_call { char *name; char *system; @@ -736,6 +742,7 @@ struct ftrace_event_call { int id; struct dentry *raw_dir; int raw_enabled; + int type; int (*raw_init)(void); int (*raw_reg)(void); void (*raw_unreg)(void); diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index 77a5c02..1d07f80 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -44,6 +44,36 @@ 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; @@ -90,19 +120,8 @@ static int ftrace_set_clr_event(char *buf, int set) if (event && strcmp(event, call->name) != 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(); - } + ftrace_event_enable_disable(call, set); + ret = 0; } return ret; @@ -273,7 +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"; @@ -304,18 +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: @@ -327,6 +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, @@ -362,6 +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; @@ -427,6 +548,7 @@ 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 @@ -435,6 +557,18 @@ event_create_dir(struct ftrace_event_call *call, struct dentry *d_events) 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) { pr_warning("Could not create debugfs " @@ -448,6 +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; } |