Re: [RFC][PATCH] bootconfig/tracing/ktest: Add ktest examples of testing bootconfig

[Steven Rostedt]

On Thu, 17 Jun 2021 11:59:21 +0900
Masami Hiramatsu <mhiramat@xxxxxxxxxx> wrote:

> > +++ b/tools/testing/ktest/examples/bootconfigs/ftrace.bconf

I'm trying to get this file to work. But I may just drop it completely.


> > @@ -0,0 +1,82 @@
> > +#!/bin/sh  
> 
> This shebang is for the syntax hilighting. Please remove it.
> 
> > +
> > +ftrace {
> > +	options = "sym-addr", "context-info"
> > +	buffer_size = 1MB
> > +}
> > +
> > +ftrace.event {
> > +	# Sample1: Make a histogram for initcall functions
> > +	synthetic.initcall_latency {
> > +                fields = "unsigned long func", "u64 lat"
> > +		hist {
> > +			keys = func.sym, lat
> > +			vals = lat
> > +			sort = lat
> > +		}  
> 
> These event.<GROUP>.<EVENT>.hist block is an experimental syntax (plan A),
> and not implemented yet.
> 
> > +	}
> > +	initcall.initcall_start.hist {
> > +		keys = func
> > +		var.ts0 = common_timestamp.usecs
> > +	}
> > +	initcall.initcall_finish.hist {
> > +		keys = func
> > +		var.lat = common_timestamp.usecs - $ts0
> > +		onmatch {
> > +			event = initcall.initcall_start
> > +			action = "initcall_latency(func, $lat)"
> > +		}
> > +	}  
> 
> So please drop this Sample1.
> 
> > +
> > +	# Sample2: kmalloc() tracing in read(2) syscall
> > +	syscalls.sys_enter_read.enable_event {
> > +		event = kmem.kmalloc
> > +		count = 1
> > +	}
> > +	syscalls.sys_exit_read.disable_event {
> > +		event = kmem.kmalloc
> > +	}
> > +
> > +	# Sample3: Stacktrace at the event
> > +	kmem.kmalloc.stacktrace {
> > +		count = 5
> > +		filter = 'bytes_req >= 65536'
> > +	}
> > +
> > +	# Sample4: Take a snapshot
> > +	block.block_unplug.snapshot {
> > +		count = 1
> > +		filter = nr_rq > 1
> > +	}
> > +
> > +	# Sample5: Trace-on/off
> > +	block.block_plug.traceon {
> > +		filter = nr_rq > 1
> > +	}
> > +	block.block_unplug.traceoff {
> > +		filter = nr_rq > 1
> > +	}

None of the above samples do anything.

I'll see if tracing.bconf does anything with the changes.

-- Steve

> > +
> > +        # Sample6: onmax
> > +	sched.sched_waking {
> > +		enable
> > +		hist {
> > +			keys = pid
> > +			ts1 = common_timestamp.usecs
> > +			filter = 'comm == "cyclictest"'
> > +		}
> > +	}