Re: [PATCH 1/7] New test case gdb.trace/signal.exp

Pedro Alves
2016-04-11T14:04:06Z

On 04/11/2016 09:40 AM, Yao Qi wrote:

> +# Record the hit times of each tracepoint in this array.
> +array set tracepoint_hits { }
> +
> +set test "tfind 0"
> +gdb_test_multiple $test $test {

Why do we need this separate "tfind 0" step? I'd think the
"tfind" loop below would be sufficient?

> + -re "Found trace frame 0, tracepoint ($decimal).*\r\n$gdb_prompt $" {
> +
> + set idx [expr $expect_out(1,string)]
> +
> + if {[info exists tracepoint_hits($idx)]} {
> + incr tracepoint_hits($idx)
> + } else {
> + set tracepoint_hits($idx) 1
> + }
> + }
> +}
> +
> +set loop 1
> +while { $loop } {
> + set test "tfind"
> + gdb_test_multiple $test $test {
> + -re "Found trace frame $decimal, tracepoint ($decimal).*\r\n$gdb_prompt $" {
> + set idx [expr $expect_out(1,string)]
> +
> + if {[info exists tracepoint_hits($idx)]} {
> + incr tracepoint_hits($idx)
> + } else {
> + set tracepoint_hits($idx) 1
> + }
> + }
> + -re "Target failed to find requested trace frame\..*\r\n$gdb_prompt $" {
> + set loop 0
> + }
> + }

If this gdb_test_multiple FAILs or times out, the loop
will continue, over and over, forever. So we need to reverse
the logic -- assume no looping, unless the "Found trace ..." regex matched.

I'd also suggest to preinitialize the array elements to 0, avoiding
the "info exists" calls in "Step 3", here:

> +# Step 3, check the number of collections on each tracepoint.
> +
> +for { set i $tpnum } { $i < [expr $tpnum + 2] } { incr i } {
> + if {[info exists tracepoint_hits($i)]} {
> + gdb_assert { $tracepoint_hits($i) == $iterations } \
> + "tracepoint $i hit $iterations times"
> + } else {
> + fail "can't find tracepoint $i hit"

Also, here I think it's nicer if PASS/FAIL messages are the same,
for test result diffing.

Thus, something like:

for { set i $tpnum } { $i < [expr $tpnum + 2] } { incr i } {
set tracepoint_hits($idx) 0
}

while { 1 } {
set test "tfind"
set idx 0
gdb_test_multiple $test $test {
-re "Found trace frame $decimal, tracepoint ($decimal).*\r\n$gdb_prompt $" {
set idx [expr $expect_out(1,string)]
incr tracepoint_hits($idx)
}
}
if {$idx == 0} {
break
}
}

# Step 3, check the number of collections on each tracepoint.
for { set i $tpnum } { $i < [expr $tpnum + 2] } { incr i } {
gdb_assert { $tracepoint_hits($i) == $iterations } \
"tracepoint $i hit $iterations times"
}

Otherwise looks good to me.

Thanks,
Pedro Alves