On Wed, 5 Dec 2018 17:05:02 +0100
Jiri Olsa <jo...@kernel.org> wrote:
> diff --git a/arch/x86/entry/common.c b/arch/x86/entry/common.c
> index 3b2490b81918..e55cf9169a03 100644
> --- a/arch/x86/entry/common.c
> +++ b/arch/x86/entry/common.c
> @@ -60,6 +60,32 @@ static void do_audit_syscall_entry(struct pt_regs *regs,
> u32 arch)
> }
> }
>
> +static void trace_block_syscall(struct pt_regs *regs, bool enter)
> +{
> + current->perf_blocked = true;
> +
> + do {
> + schedule_timeout(100 * HZ);
> + current->perf_blocked_cnt = 0;
> +
> + if (enter) {
> + /* perf syscalls:* enter */
> + perf_trace_syscall_enter(regs);
> +
> + /* perf raw_syscalls:* enter */
> + perf_trace_sys_enter(&event_sys_enter, regs,
> regs->orig_ax);
> + } else {
> + /* perf syscalls:* enter */
> + perf_trace_syscall_exit(regs);
> +
> + /* perf raw_syscalls:* enter */
> + perf_trace_sys_exit(&event_sys_exit, regs, regs->ax);
> + }
> + } while (current->perf_blocked_cnt);
I was thinking, if the process reading the perf buffer dies, how do we
tell this task to continue on?
-- Steve
> +
> + current->perf_blocked = false;
> +}
> +
