Hi Oleg, On Mon, 4 Nov 2013 15:35:17 +0100, Oleg Nesterov wrote: > Hi Namhyung, > > On 11/04, Namhyung Kim wrote: >> >> >> >> >> + if (atomic_dec_and_test(&uprobe_buffer_ref)) { >> >> + free_percpu(uprobe_cpu_buffer); >> >> + uprobe_cpu_buffer = NULL; >> >> + } >> >> + >> >> WARN_ON(!uprobe_filter_is_empty(&tu->filter)); >> > >> > Do we really need atomic_t? probe_event_enable/disable is called under >> > event_mutex and we rely on this fact anyway. >> >> Looking at the code, it seems probe_event_enable/disable() is called >> without event_mutex when it called from sys_perf_event_open(). > > Where? > > __ftrace_set_clr_event(), perf_trace_init() or perf_trace_destroy() > hold event_mutex. We rely on this fact anyway.
Ah, you're right. My eyes simply missed it. ;-) Thanks, Namhyung -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/