Hi Stephen, I hope you are the correct person for this question. https://lkml.org/lkml/2016/2/27/192 -- Sanketh Nalli College of Letters and Sciences University of Wisconsin - Madison
________________________________________ From: SANKETH NALLI Sent: Saturday, February 27, 2016 2:30 PM To: [email protected] Subject: tracing: Allow mmio tracer to display trace_printk() and other events Hi, I am trying to print trace markers from inside the kernel using the mmio-tracer's mmiotrace_printk routine but it doesn't get printed. Looking back, i found this thread and applied the said patch but that didn't work either. https://lkml.org/lkml/2010/5/4/465 Thereafter, I followed the code path starting at mmiotrace_printk which lead to __trace_array_vprintk and in there, tbuffer = get_trace_buf(); if (!tbuffer) { /* pr_info("invalid buffer.\n"); */ len = 0; goto out; } tbuffer turns out to be null which is why the call to mmiotrace_printk returns without printing my marker. Has this been fixed or looked into ? Any help would be much appreciated. Thanks. -- Sanketh Nalli College of Letters and Sciences University of Wisconsin - Madison
