Re: [PATCH] dynamic debug: allow printing to trace event

From: John Ogness
Date: Wed Jul 22 2020 - 09:52:28 EST


On 2020-07-21, Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:
>> diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c
>> index 321437bbf87d..9f6d8867af7c 100644
>> --- a/lib/dynamic_debug.c
>> +++ b/lib/dynamic_debug.c
[..]
>> +static void dynamic_printk(unsigned int flags, const char *fmt, ...)
>> +{
>> + if (flags & _DPRINTK_FLAGS_TRACE) {
>> + va_list args;
>> +
>> + va_start(args, fmt);
>> + /*
>> + * All callers include the KERN_DEBUG prefix to keep the
>> + * vprintk case simple; strip it out for tracing.
>> + */
>> + dynamic_trace(fmt + strlen(KERN_DEBUG), args);

Do we really need a separate tracing event for this? Why not just:

ftrace_vprintk(fmt + strlen(KERN_DEBUG), args);

John Ogness