Messages in this thread | | | Date | Mon, 1 Jul 2013 21:45:55 +0200 | From | Oleg Nesterov <> | Subject | Re: [PATCH v2 3/4] tracing/kprobes: Don't pass addr=ip to perf_trace_buf_submit() |
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On 07/01, Steven Rostedt wrote: > > On Thu, 2013-06-20 at 19:38 +0200, Oleg Nesterov wrote: > > kprobe_perf_func() and kretprobe_perf_func() pass addr=ip to > > perf_trace_buf_submit() for no reason. > > > > This sets perf_sample_data->addr for PERF_SAMPLE_ADDR, we already > > have perf_sample_data->ip initialized if PERF_SAMPLE_IP. > > This change log is confusing. I have no idea what this is trying to fix. > Can you explain what is the issue here and what this change fixes.
Sorry for confusion, this fixes nothing.
Just there is no reason to pass "addr = kp.addr", we report it in entry.
Note also that kprobes is the last user perf_trace_buf_submit(addr != 0), perhaps we can kill this arg and __perf_addr().
See also 32520b2c6 "Don't pass addr=ip to perf_trace_buf_submit()".
> Thanks, > > -- Steve > > > > > Signed-off-by: Oleg Nesterov <oleg@redhat.com> > > --- > > kernel/trace/trace_kprobe.c | 6 ++---- > > 1 files changed, 2 insertions(+), 4 deletions(-) > > > > diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c > > index 3432652..141c682 100644 > > --- a/kernel/trace/trace_kprobe.c > > +++ b/kernel/trace/trace_kprobe.c > > @@ -1163,8 +1163,7 @@ kprobe_perf_func(struct trace_probe *tp, struct pt_regs *regs) > > entry->ip = (unsigned long)tp->rp.kp.addr; > > memset(&entry[1], 0, dsize); > > store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize); > > - perf_trace_buf_submit(entry, size, rctx, > > - entry->ip, 1, regs, head, NULL); > > + perf_trace_buf_submit(entry, size, rctx, 0, 1, regs, head, NULL); > > } > > > > /* Kretprobe profile handler */ > > @@ -1197,8 +1196,7 @@ kretprobe_perf_func(struct trace_probe *tp, struct kretprobe_instance *ri, > > entry->func = (unsigned long)tp->rp.kp.addr; > > entry->ret_ip = (unsigned long)ri->ret_addr; > > store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize); > > - perf_trace_buf_submit(entry, size, rctx, > > - entry->ret_ip, 1, regs, head, NULL); > > + perf_trace_buf_submit(entry, size, rctx, 0, 1, regs, head, NULL); > > } > > #endif /* CONFIG_PERF_EVENTS */ > > > >
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