/* * trace context switch * * Copyright (C) 2007 Steven Rostedt * */ #include #include #include #include #include #include "trace.h" static int sched_ref; static DEFINE_MUTEX(sched_register_mutex); static void probe_sched_switch(void *ignore, bool preempt, struct task_struct *prev, struct task_struct *next) { if (unlikely(!sched_ref)) return; tracing_record_cmdline(prev); tracing_record_cmdline(next); } static void probe_sched_wakeup(void *ignore, struct task_struct *wakee) { if (unlikely(!sched_ref)) return; tracing_record_cmdline(current); } static int tracing_sched_register(void) { int ret; ret = register_trace_sched_wakeup(probe_sched_wakeup, NULL); if (ret) { pr_info("wakeup trace: Couldn't activate tracepoint" " probe to kernel_sched_wakeup\n"); return ret; } ret = register_trace_sched_wakeup_new(probe_sched_wakeup, NULL); if (ret) { pr_info("wakeup trace: Couldn't activate tracepoint" " probe to kernel_sched_wakeup_new\n"); goto fail_deprobe; } ret = register_trace_sched_switch(probe_sched_switch, NULL); if (ret) { pr_info("sched trace: Couldn't activate tracepoint" " probe to kernel_sched_switch\n"); goto fail_deprobe_wake_new; } return ret; fail_deprobe_wake_new: unregister_trace_sched_wakeup_new(probe_sched_wakeup, NULL); fail_deprobe: unregister_trace_sched_wakeup(probe_sched_wakeup, NULL); return ret; } static void tracing_sched_unregister(void) { unregister_trace_sched_switch(probe_sched_switch, NULL); unregister_trace_sched_wakeup_new(probe_sched_wakeup, NULL); unregister_trace_sched_wakeup(probe_sched_wakeup, NULL); } static void tracing_start_sched_switch(void) { mutex_lock(&sched_register_mutex); if (!(sched_ref++)) tracing_sched_register(); mutex_unlock(&sched_register_mutex); } static void tracing_stop_sched_switch(void) { mutex_lock(&sched_register_mutex); if (!(--sched_ref)) tracing_sched_unregister(); mutex_unlock(&sched_register_mutex); } void tracing_start_cmdline_record(void) { tracing_start_sched_switch(); } void tracing_stop_cmdline_record(void) { tracing_stop_sched_switch(); } v/gateway_common.c?h=nds-private-remove&id=0becc0ae5b42828785b589f686725ff5bc3b9b25'>diff
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authorThomas Gleixner <tglx@linutronix.de>2017-01-31 09:37:34 +0100
committerThomas Gleixner <tglx@linutronix.de>2017-01-31 21:47:58 +0100
commit0becc0ae5b42828785b589f686725ff5bc3b9b25 (patch)
treebe6d0e1f37c38ed0a7dd5da2d4b1e93f0fb43101 /net/batman-adv/gateway_common.c
parent24c2503255d35c269b67162c397a1a1c1e02f6ce (diff)
x86/mce: Make timer handling more robust
Erik reported that on a preproduction hardware a CMCI storm triggers the BUG_ON in add_timer_on(). The reason is that the per CPU MCE timer is started by the CMCI logic before the MCE CPU hotplug callback starts the timer with add_timer_on(). So the timer is already queued which triggers the BUG. Using add_timer_on() is pretty pointless in this code because the timer is strictlty per CPU, initialized as pinned and all operations which arm the timer happen on the CPU to which the timer belongs. Simplify the whole machinery by using mod_timer() instead of add_timer_on() which avoids the problem because mod_timer() can handle already queued timers. Use __start_timer() everywhere so the earliest armed expiry time is preserved. Reported-by: Erik Veijola <erik.veijola@intel.com> Tested-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@alien8.de> Cc: Tony Luck <tony.luck@intel.com> Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1701310936080.3457@nanos Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'net/batman-adv/gateway_common.c')