Re: [PATCH] perf test: Switch basic bpf filtering test to use syscall tracepoint

From: Arnaldo Carvalho de Melo
Date: Mon Jan 30 2023 - 09:10:06 EST


Em Mon, Jan 30, 2023 at 02:28:49PM +0530, kajoljain escreveu:
>
>
> On 1/23/23 14:02, Naveen N. Rao wrote:
> > BPF filtering tests can sometime fail. Running the test in verbose mode
> > shows the following:
> > $ sudo perf test 42
> > 42: BPF filter :
> > 42.1: Basic BPF filtering : FAILED!
> > 42.2: BPF pinning : Skip
> > 42.3: BPF prologue generation : Skip
> > $ perf --version
> > perf version 4.18.0-425.3.1.el8.ppc64le
> > $ sudo perf test -v 42
> > 42: BPF filter :
> > 42.1: Basic BPF filtering :
> > --- start ---
> > test child forked, pid 711060
> > ...
> > bpf: config 'func=do_epoll_wait' is ok
> > Looking at the vmlinux_path (8 entries long)
> > Using /usr/lib/debug/lib/modules/4.18.0-425.3.1.el8.ppc64le/vmlinux for symbols
> > Open Debuginfo file: /usr/lib/debug/.build-id/81/56f5a07f92ccb62c5600ba0e4aacfb5f3a7534.debug
> > Try to find probe point from debuginfo.
> > Matched function: do_epoll_wait [4ef8cb0]
> > found inline addr: 0xc00000000061dbe4
> > Probe point found: __se_compat_sys_epoll_pwait+196
> > found inline addr: 0xc00000000061d9f4
> > Probe point found: __se_sys_epoll_pwait+196
> > found inline addr: 0xc00000000061d824
> > Probe point found: __se_sys_epoll_wait+36
> > Found 3 probe_trace_events.
> > Opening /sys/kernel/tracing//kprobe_events write=1
> > ...
> > BPF filter result incorrect, expected 56, got 56 samples
> > test child finished with -1
> > ---- end ----
> > BPF filter subtest 1: FAILED!
>
> Patch looks good to me.
>
> Reviewed-by: Kajol Jain<kjain@xxxxxxxxxxxxx>

Thanks, added to that cset, as it is still just on tmp.perf/core.

- Arnaldo