mirror of https://gitee.com/openkylin/linux.git
14a866c567
Impact: new ftrace_graph_stop function While developing more features of function graph, I hit a bug that caused the WARN_ON to trigger in the prepare_ftrace_return function. Well, it was hard for me to find out that was happening because the bug would not print, it would just cause a hard lockup or reboot. The reason is that it is not safe to call printk from this function. Looking further, I also found that it calls unregister_ftrace_graph, which grabs a mutex and calls kstop machine. This would definitely lock the box up if it were to trigger. This patch adds a fast and safe ftrace_graph_stop() which will stop the function tracer. Then it is safe to call the WARN ON. Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> |
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| .. | ||
| Kconfig | ||
| Makefile | ||
| ftrace.c | ||
| ring_buffer.c | ||
| trace.c | ||
| trace.h | ||
| trace_boot.c | ||
| trace_branch.c | ||
| trace_bts.c | ||
| trace_functions.c | ||
| trace_functions_graph.c | ||
| trace_irqsoff.c | ||
| trace_mmiotrace.c | ||
| trace_nop.c | ||
| trace_power.c | ||
| trace_sched_switch.c | ||
| trace_sched_wakeup.c | ||
| trace_selftest.c | ||
| trace_selftest_dynamic.c | ||
| trace_stack.c | ||
| trace_sysprof.c | ||