diff options
| -rw-r--r-- | kernel/trace/trace.h | 15 | ||||
| -rw-r--r-- | kernel/trace/trace_events.c | 86 | ||||
| -rw-r--r-- | kernel/trace/trace_events_filter.c | 80 |
3 files changed, 175 insertions, 6 deletions
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index d9eb39e4bb38..f267723c3c52 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -804,6 +804,18 @@ struct ftrace_event_call { #endif }; +struct event_subsystem { + struct list_head list; + const char *name; + struct dentry *entry; + struct filter_pred **preds; +}; + +#define events_for_each(event) \ + for (event = __start_ftrace_events; \ + (unsigned long)event < (unsigned long)__stop_ftrace_events; \ + event++) + #define MAX_FILTER_PRED 8 struct filter_pred; @@ -832,6 +844,9 @@ extern int filter_add_pred(struct ftrace_event_call *call, struct filter_pred *pred); extern void filter_free_preds(struct ftrace_event_call *call); extern int filter_match_preds(struct ftrace_event_call *call, void *rec); +extern void filter_free_subsystem_preds(struct event_subsystem *system); +extern int filter_add_subsystem_pred(struct event_subsystem *system, + struct filter_pred *pred); void event_trace_printk(unsigned long ip, const char *fmt, ...); extern struct ftrace_event_call __start_ftrace_events[]; diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index 97470c48956e..97d4daaddd9a 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -524,6 +524,71 @@ event_filter_write(struct file *filp, const char __user *ubuf, size_t cnt, return cnt; } +static ssize_t +subsystem_filter_read(struct file *filp, char __user *ubuf, size_t cnt, + loff_t *ppos) +{ + struct event_subsystem *system = filp->private_data; + struct trace_seq *s; + int r; + + if (*ppos) + return 0; + + s = kmalloc(sizeof(*s), GFP_KERNEL); + if (!s) + return -ENOMEM; + + trace_seq_init(s); + + r = filter_print_preds(system->preds, s->buffer); + r = simple_read_from_buffer(ubuf, cnt, ppos, s->buffer, r); + + kfree(s); + + return r; +} + +static ssize_t +subsystem_filter_write(struct file *filp, const char __user *ubuf, size_t cnt, + loff_t *ppos) +{ + struct event_subsystem *system = filp->private_data; + char buf[64], *pbuf = buf; + struct filter_pred *pred; + int err; + + if (cnt >= sizeof(buf)) + return -EINVAL; + + if (copy_from_user(&buf, ubuf, cnt)) + return -EFAULT; + + pred = kzalloc(sizeof(*pred), GFP_KERNEL); + if (!pred) + return -ENOMEM; + + err = filter_parse(&pbuf, pred); + if (err < 0) { + filter_free_pred(pred); + return err; + } + + if (pred->clear) { + filter_free_subsystem_preds(system); + return cnt; + } + + if (filter_add_subsystem_pred(system, pred)) { + filter_free_pred(pred); + return -EINVAL; + } + + *ppos += cnt; + + return cnt; +} + static const struct seq_operations show_event_seq_ops = { .start = t_start, .next = t_next, @@ -575,6 +640,12 @@ static const struct file_operations ftrace_event_filter_fops = { .write = event_filter_write, }; +static const struct file_operations ftrace_subsystem_filter_fops = { + .open = tracing_open_generic, + .read = subsystem_filter_read, + .write = subsystem_filter_write, +}; + static struct dentry *event_trace_events_dir(void) { static struct dentry *d_tracer; @@ -595,18 +666,13 @@ 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; + struct dentry *entry; /* First see if we did not already create this dir */ list_for_each_entry(system, &event_subsystems, list) { @@ -633,6 +699,14 @@ event_subsystem_dir(const char *name, struct dentry *d_events) system->name = name; list_add(&system->list, &event_subsystems); + system->preds = NULL; + + entry = debugfs_create_file("filter", 0444, system->entry, system, + &ftrace_subsystem_filter_fops); + if (!entry) + pr_warning("Could not create debugfs " + "'%s/filter' entry\n", name); + return system->entry; } diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c index 8e8c5fa25be9..1ab20cee0e4c 100644 --- a/kernel/trace/trace_events_filter.c +++ b/kernel/trace/trace_events_filter.c @@ -181,6 +181,27 @@ void filter_free_preds(struct ftrace_event_call *call) } } +void filter_free_subsystem_preds(struct event_subsystem *system) +{ + struct ftrace_event_call *call = __start_ftrace_events; + int i; + + if (system->preds) { + for (i = 0; i < MAX_FILTER_PRED; i++) + filter_free_pred(system->preds[i]); + kfree(system->preds); + system->preds = NULL; + } + + events_for_each(call) { + if (!call->name || !call->regfunc) + continue; + + if (!strcmp(call->system, system->name)) + filter_free_preds(call); + } +} + static int __filter_add_pred(struct ftrace_event_call *call, struct filter_pred *pred) { @@ -250,6 +271,65 @@ int filter_add_pred(struct ftrace_event_call *call, struct filter_pred *pred) return __filter_add_pred(call, pred); } +static struct filter_pred *copy_pred(struct filter_pred *pred) +{ + struct filter_pred *new_pred = kmalloc(sizeof(*pred), GFP_KERNEL); + if (!new_pred) + return NULL; + + memcpy(new_pred, pred, sizeof(*pred)); + if (pred->str_val) { + new_pred->str_val = kstrdup(pred->str_val, GFP_KERNEL); + new_pred->field_name = kstrdup(pred->field_name, GFP_KERNEL); + if (!new_pred->str_val) { + kfree(new_pred); + return NULL; + } + } + + return new_pred; +} + +int filter_add_subsystem_pred(struct event_subsystem *system, + struct filter_pred *pred) +{ + struct ftrace_event_call *call = __start_ftrace_events; + struct filter_pred *event_pred; + int i; + + if (system->preds && !pred->compound) + filter_free_subsystem_preds(system); + + if (!system->preds) { + system->preds = kzalloc(MAX_FILTER_PRED * sizeof(pred), + GFP_KERNEL); + if (!system->preds) + return -ENOMEM; + } + + for (i = 0; i < MAX_FILTER_PRED; i++) { + if (!system->preds[i]) { + system->preds[i] = pred; + break; + } + if (i == MAX_FILTER_PRED - 1) + return -EINVAL; + } + + events_for_each(call) { + if (!call->name || !call->regfunc) + continue; + + if (!strcmp(call->system, system->name)) { + event_pred = copy_pred(pred); + if (event_pred) + filter_add_pred(call, event_pred); + } + } + + return 0; +} + int filter_parse(char **pbuf, struct filter_pred *pred) { char *tmp, *tok, *val_str = NULL; |