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07695fa04e
Impact: fix race condition in sched_switch tracer This patch fixes a race condition in the sched_switch tracer. If several tasks (IE: concurrent initcalls) are playing with tracing_start_cmdline_record() and tracing_stop_cmdline_record(), the following situation could happen: _ Task A and B are using the same tracepoint probe. Task A holds it. Task B is sleeping and doesn't hold it. _ Task A frees the sched tracer, then sched_ref is decremented to 0. _ Task A is preempted and hadn't yet unregistered its tracepoint probe, then B runs. _ B increments sched_ref, sees it's 1 and then guess it has to register its probe. But it has not been freed by task A. _ A lot of bad things can happen after that... Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> |
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| .. | ||
| ftrace.c | ||
| Kconfig | ||
| Makefile | ||
| ring_buffer.c | ||
| trace_boot.c | ||
| trace_functions.c | ||
| trace_irqsoff.c | ||
| trace_mmiotrace.c | ||
| trace_nop.c | ||
| trace_sched_switch.c | ||
| trace_sched_wakeup.c | ||
| trace_selftest_dynamic.c | ||
| trace_selftest.c | ||
| trace_stack.c | ||
| trace_sysprof.c | ||
| trace.c | ||
| trace.h | ||