diff options
| -rw-r--r-- | kernel/trace/trace_ksym.c | 53 |
1 files changed, 35 insertions, 18 deletions
diff --git a/kernel/trace/trace_ksym.c b/kernel/trace/trace_ksym.c index cd5cb656c3d..2fde875ead4 100644 --- a/kernel/trace/trace_ksym.c +++ b/kernel/trace/trace_ksym.c @@ -163,8 +163,6 @@ static int parse_ksym_trace_str(char *input_string, char **ksymname, { int ret; - strstrip(input_string); - *ksymname = strsep(&input_string, ":"); *addr = kallsyms_lookup_name(*ksymname); @@ -262,6 +260,25 @@ static ssize_t ksym_trace_filter_read(struct file *filp, char __user *ubuf, return cnt; } +static void __ksym_trace_reset(void) +{ + struct trace_ksym *entry; + struct hlist_node *node, *node1; + + mutex_lock(&ksym_tracer_mutex); + hlist_for_each_entry_safe(entry, node, node1, &ksym_filter_head, + ksym_hlist) { + unregister_kernel_hw_breakpoint(entry->ksym_hbp); + ksym_filter_entry_count--; + hlist_del_rcu(&(entry->ksym_hlist)); + synchronize_rcu(); + kfree(entry->ksym_hbp->info.name); + kfree(entry->ksym_hbp); + kfree(entry); + } + mutex_unlock(&ksym_tracer_mutex); +} + static ssize_t ksym_trace_filter_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos) @@ -282,6 +299,21 @@ static ssize_t ksym_trace_filter_write(struct file *file, } input_string[count] = '\0'; + strstrip(input_string); + + /* + * Clear all breakpoints if: + * 1: echo > ksym_trace_filter + * 2: echo 0 > ksym_trace_filter + * 3: echo "*:---" > ksym_trace_filter + */ + if (!input_string[0] || !strcmp(input_string, "0") || + !strcmp(input_string, "*:---")) { + __ksym_trace_reset(); + kfree(input_string); + return count; + } + ret = op = parse_ksym_trace_str(input_string, &ksymname, &ksym_addr); if (ret < 0) { kfree(input_string); @@ -341,23 +373,8 @@ static const struct file_operations ksym_tracing_fops = { static void ksym_trace_reset(struct trace_array *tr) { - struct trace_ksym *entry; - struct hlist_node *node, *node1; - ksym_tracing_enabled = 0; - - mutex_lock(&ksym_tracer_mutex); - hlist_for_each_entry_safe(entry, node, node1, &ksym_filter_head, - ksym_hlist) { - unregister_kernel_hw_breakpoint(entry->ksym_hbp); - ksym_filter_entry_count--; - hlist_del_rcu(&(entry->ksym_hlist)); - synchronize_rcu(); - kfree(entry->ksym_hbp->info.name); - kfree(entry->ksym_hbp); - kfree(entry); - } - mutex_unlock(&ksym_tracer_mutex); + __ksym_trace_reset(); } static int ksym_trace_init(struct trace_array *tr) |