This is the mail archive of the
gdb-patches@sourceware.org
mailing list for the GDB project.
Re: [PATCH 1/2] watchpoint-reuse-slot.exp: skip some tests on targets have different wp and bp registers
- From: Yao Qi <qiyaoltc at gmail dot com>
- To: Pedro Alves <palves at redhat dot com>
- Cc: Yao Qi <qiyaoltc at gmail dot com>, gdb-patches at sourceware dot org
- Date: Mon, 16 Mar 2015 14:01:22 +0000
- Subject: Re: [PATCH 1/2] watchpoint-reuse-slot.exp: skip some tests on targets have different wp and bp registers
- Authentication-results: sourceware.org; auth=none
- References: <1426257692-30461-1-git-send-email-qiyaoltc at gmail dot com> <5506CDF2 dot 4090400 at redhat dot com>
Pedro Alves <palves@redhat.com> writes:
> Hmm, is this just to save test time? If so, I'd prefer not skipping,
> as it may always catch other bugs, in the target backends or
> the kernel.
No, watchpoint-reuse-slot.exp sets some HW breakpoint/watchpoint on some
address doesn't meet the alignment requirements by kernel, kernel
will reject the ptrace (PTRACE_SETHBPREGS) call, and some fails are
caused, for example:
(gdb) PASS: gdb.base/watchpoint-reuse-slot.exp: always-inserted off: watch x hbreak: : width 1, iter 0: base + 0: delete $bpnum
hbreak *(buf.byte + 0 + 1)^M
Hardware assisted breakpoint 80 at 0x410a61^M
(gdb) PASS: gdb.base/watchpoint-reuse-slot.exp: always-inserted off: watch x hbreak: : width 1, iter 0: base + 1: hbreak *(buf.byte + 0 + 1)
stepi^M
Warning:^M
Cannot insert hardware breakpoint 80.^M
Could not insert hardware breakpoints:^M
You may have requested too many hardware breakpoints/watchpoints.^M
^M
(gdb) FAIL: gdb.base/watchpoint-reuse-slot.exp: always-inserted off: watch x hbreak: : width 1, iter 0: base + 1: stepi advanced
hbreak *(buf.byte + 0 + 1)^M
Hardware assisted breakpoint 440 at 0x410a61^M
Warning:^M
Cannot insert hardware breakpoint 440.^M
Could not insert hardware breakpoints:^M
You may have requested too many hardware breakpoints/watchpoints.^M
^M
(gdb) FAIL: gdb.base/watchpoint-reuse-slot.exp: always-inserted on: watch x hbreak: : width 1, iter 0: base + 1: hbreak *(buf.byte + 0 + 1)
Do you suggest that we don't skip these tests even requested
breakpoint/watchpoint don't go in the same slot (debugging register)? so
that the test can cover more. If the requested address of HW
breakpoint/watchpoint doesn't meet the arch/kernel requirements, we can
skip it, is it OK?
The inner loop of test has two parts, "base + 0" and "base + 1",
append prefix "$cmd1 x $cmd2: "
with_test_prefix "$prefix: width $width, iter $x" {
with_test_prefix "base + 0" {
watch_command $cmd1 $x 0 $width
stepi
gdb_test_no_output "delete \$bpnum"
}
with_test_prefix "base + 1" {
watch_command $cmd2 $x 1 $width
stepi
gdb_test_no_output "delete \$bpnum"
}
}
if we skip "base + 1" part, do we skip "base + 0" too? if not, prefix in
test summary "$cmd1 x $cmd2: " doesn't reflect the fact.
>
> Despite the test's file name, the test doesn't actually create two
> breakpoints/watchpoints at the same time, as mentioned at the top
> of the file.
Yes, only one breakpoint/watchpoint is inserted at a time.
--
Yao (éå)