Re: [PATCH 1/1] uprobes/tracing: Don't pass addr=ip to perf_trace_buf_submit()

From: Masami Hiramatsu
Date: Thu Apr 11 2013 - 06:19:14 EST


(2013/04/10 23:58), Oleg Nesterov wrote:
> uprobe_perf_print() passes 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.
>
> Signed-off-by: Oleg Nesterov <oleg@xxxxxxxxxx>

Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@xxxxxxxxxxx>

Thank you!

> ---
> kernel/trace/trace_uprobe.c | 8 +++-----
> 1 files changed, 3 insertions(+), 5 deletions(-)
>
> diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c
> index 2d08bea..37ccb72 100644
> --- a/kernel/trace/trace_uprobe.c
> +++ b/kernel/trace/trace_uprobe.c
> @@ -811,7 +811,6 @@ static void uprobe_perf_print(struct trace_uprobe *tu,
> struct ftrace_event_call *call = &tu->call;
> struct uprobe_trace_entry_head *entry;
> struct hlist_head *head;
> - unsigned long ip;
> void *data;
> int size, rctx, i;
>
> @@ -825,13 +824,12 @@ static void uprobe_perf_print(struct trace_uprobe *tu,
> if (!entry)
> goto out;
>
> - ip = instruction_pointer(regs);
> if (is_ret_probe(tu)) {
> entry->vaddr[0] = func;
> - entry->vaddr[1] = ip;
> + entry->vaddr[1] = instruction_pointer(regs);
> data = DATAOF_TRACE_ENTRY(entry, true);
> } else {
> - entry->vaddr[0] = ip;
> + entry->vaddr[0] = instruction_pointer(regs);
> data = DATAOF_TRACE_ENTRY(entry, false);
> }
>
> @@ -839,7 +837,7 @@ static void uprobe_perf_print(struct trace_uprobe *tu,
> call_fetch(&tu->args[i].fetch, regs, data + tu->args[i].offset);
>
> head = this_cpu_ptr(call->perf_events);
> - perf_trace_buf_submit(entry, size, rctx, ip, 1, regs, head, NULL);
> + perf_trace_buf_submit(entry, size, rctx, 0, 1, regs, head, NULL);
> out:
> preempt_enable();
> }
>


--
Masami HIRAMATSU
IT Management Research Dept. Linux Technology Center
Hitachi, Ltd., Yokohama Research Laboratory
E-mail: masami.hiramatsu.pt@xxxxxxxxxxx


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/