diff options
Diffstat (limited to 'kernel/trace/trace.c')
| -rw-r--r-- | kernel/trace/trace.c | 93 |
1 files changed, 87 insertions, 6 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 5653c6b07ba..4ee6f037522 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -43,6 +43,20 @@ unsigned long __read_mostly tracing_max_latency = (cycle_t)ULONG_MAX; unsigned long __read_mostly tracing_thresh; +/* For tracers that don't implement custom flags */ +static struct tracer_opt dummy_tracer_opt[] = { + { } +}; + +static struct tracer_flags dummy_tracer_flags = { + .val = 0, + .opts = dummy_tracer_opt +}; + +static int dummy_set_flag(u32 old_flags, u32 bit, int set) +{ + return 0; +} /* * Kill all tracing for good (never come back). @@ -537,6 +551,14 @@ int register_tracer(struct tracer *type) } } + if (!type->set_flag) + type->set_flag = &dummy_set_flag; + if (!type->flags) + type->flags = &dummy_tracer_flags; + else + if (!type->flags->opts) + type->flags->opts = dummy_tracer_opt; + #ifdef CONFIG_FTRACE_STARTUP_TEST if (type->selftest) { struct tracer *saved_tracer = current_trace; @@ -840,6 +862,7 @@ static void __trace_function_return(struct trace_array *tr, entry->parent_ip = trace->ret; entry->rettime = trace->rettime; entry->calltime = trace->calltime; + entry->overrun = trace->overrun; ring_buffer_unlock_commit(global_trace.buffer, event, irq_flags); } #endif @@ -2436,10 +2459,13 @@ static ssize_t tracing_trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos) { + int i; char *buf; int r = 0; int len = 0; - int i; + u32 tracer_flags = current_trace->flags->val; + struct tracer_opt *trace_opts = current_trace->flags->opts; + /* calulate max size */ for (i = 0; trace_options[i]; i++) { @@ -2447,6 +2473,15 @@ tracing_trace_options_read(struct file *filp, char __user *ubuf, len += 3; /* "no" and space */ } + /* + * Increase the size with names of options specific + * of the current tracer. + */ + for (i = 0; trace_opts[i].name; i++) { + len += strlen(trace_opts[i].name); + len += 3; /* "no" and space */ + } + /* +2 for \n and \0 */ buf = kmalloc(len + 2, GFP_KERNEL); if (!buf) @@ -2459,6 +2494,15 @@ tracing_trace_options_read(struct file *filp, char __user *ubuf, r += sprintf(buf + r, "no%s ", trace_options[i]); } + for (i = 0; trace_opts[i].name; i++) { + if (tracer_flags & trace_opts[i].bit) + r += sprintf(buf + r, "%s ", + trace_opts[i].name); + else + r += sprintf(buf + r, "no%s ", + trace_opts[i].name); + } + r += sprintf(buf + r, "\n"); WARN_ON(r >= len + 2); @@ -2469,6 +2513,40 @@ tracing_trace_options_read(struct file *filp, char __user *ubuf, return r; } +/* Try to assign a tracer specific option */ +static int set_tracer_option(struct tracer *trace, char *cmp, int neg) +{ + struct tracer_flags *trace_flags = trace->flags; + struct tracer_opt *opts = NULL; + int ret = 0, i = 0; + int len; + + for (i = 0; trace_flags->opts[i].name; i++) { + opts = &trace_flags->opts[i]; + len = strlen(opts->name); + + if (strncmp(cmp, opts->name, len) == 0) { + ret = trace->set_flag(trace_flags->val, + opts->bit, !neg); + break; + } + } + /* Not found */ + if (!trace_flags->opts[i].name) + return -EINVAL; + + /* Refused to handle */ + if (ret) + return ret; + + if (neg) + trace_flags->val &= ~opts->bit; + else + trace_flags->val |= opts->bit; + + return 0; +} + static ssize_t tracing_trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, loff_t *ppos) @@ -2476,6 +2554,7 @@ tracing_trace_options_write(struct file *filp, const char __user *ubuf, char buf[64]; char *cmp = buf; int neg = 0; + int ret; int i; if (cnt >= sizeof(buf)) @@ -2502,11 +2581,13 @@ tracing_trace_options_write(struct file *filp, const char __user *ubuf, break; } } - /* - * If no option could be set, return an error: - */ - if (!trace_options[i]) - return -EINVAL; + + /* If no option could be set, test the specific tracer options */ + if (!trace_options[i]) { + ret = set_tracer_option(current_trace, cmp, neg); + if (ret) + return ret; + } filp->f_pos += cnt; |