diff options
author | Sebastian Andrzej Siewior <bigeasy@linutronix.de> | 2016-02-11 22:06:28 +0100 |
---|---|---|
committer | Steven Rostedt <rostedt@goodmis.org> | 2016-11-16 14:23:19 -0500 |
commit | 5a3f1e62b69875a8ea656a2c5a59ddee54d468ae (patch) | |
tree | 0c25609837f39ff5f25614da302e05537d7f4bda | |
parent | 691e9c50c66c4576435a39524a2e4e30b760a598 (diff) | |
download | linux-rt-5a3f1e62b69875a8ea656a2c5a59ddee54d468ae.tar.gz |
kernel: sched: Fix preempt_disable_ip recodring for preempt_disable()
preempt_disable() invokes preempt_count_add() which saves the caller in
current->preempt_disable_ip. It uses CALLER_ADDR1 which does not look for its
caller but for the parent of the caller. Which means we get the correct caller
for something like spin_lock() unless the architectures inlines those
invocations. It is always wrong for preempt_disable() or local_bh_disable().
This patch makes the function get_parent_ip() which tries CALLER_ADDR0,1,2 if
the former is a locking function. This seems to record the preempt_disable()
caller properly for preempt_disable() itself as well as for get_cpu_var() or
local_bh_disable().
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
-rw-r--r-- | include/linux/ftrace.h | 12 | ||||
-rw-r--r-- | include/linux/sched.h | 2 | ||||
-rw-r--r-- | kernel/sched/core.c | 14 | ||||
-rw-r--r-- | kernel/softirq.c | 2 |
4 files changed, 15 insertions, 15 deletions
diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index bfbcd439e2c6..93bce698fb86 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -476,6 +476,18 @@ static inline void __ftrace_enabled_restore(int enabled) # endif #endif /* ifndef HAVE_ARCH_CALLER_ADDR */ +static inline unsigned long get_lock_parent_ip(void) +{ + unsigned long addr = CALLER_ADDR0; + + if (!in_lock_functions(addr)) + return addr; + addr = CALLER_ADDR1; + if (!in_lock_functions(addr)) + return addr; + return CALLER_ADDR2; +} + #ifdef CONFIG_IRQSOFF_TRACER extern void time_hardirqs_on(unsigned long a0, unsigned long a1); extern void time_hardirqs_off(unsigned long a0, unsigned long a1); diff --git a/include/linux/sched.h b/include/linux/sched.h index daf469059630..029575fb9bc8 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -148,8 +148,6 @@ extern unsigned long this_cpu_load(void); extern void calc_global_load(unsigned long ticks); extern void update_cpu_load_nohz(void); -extern unsigned long get_parent_ip(unsigned long addr); - struct seq_file; struct cfs_rq; struct task_group; diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 9c9ff71587ea..9114bf5bd0ab 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -3241,16 +3241,6 @@ void scheduler_tick(void) #endif } -notrace unsigned long get_parent_ip(unsigned long addr) -{ - if (in_lock_functions(addr)) { - addr = CALLER_ADDR2; - if (in_lock_functions(addr)) - addr = CALLER_ADDR3; - } - return addr; -} - #if defined(CONFIG_PREEMPT) && (defined(CONFIG_DEBUG_PREEMPT) || \ defined(CONFIG_PREEMPT_TRACER)) @@ -3272,7 +3262,7 @@ void __kprobes add_preempt_count(int val) PREEMPT_MASK - 10); #endif if (preempt_count() == val) { - unsigned long ip = get_parent_ip(CALLER_ADDR1); + unsigned long ip = get_lock_parent_ip(); #ifdef CONFIG_DEBUG_PREEMPT current->preempt_disable_ip = ip; #endif @@ -3298,7 +3288,7 @@ void __kprobes sub_preempt_count(int val) #endif if (preempt_count() == val) - trace_preempt_on(CALLER_ADDR0, get_parent_ip(CALLER_ADDR1)); + trace_preempt_on(CALLER_ADDR0, get_lock_parent_ip()); preempt_count() -= val; } EXPORT_SYMBOL(sub_preempt_count); diff --git a/kernel/softirq.c b/kernel/softirq.c index d2c870a826da..2cdd5102331b 100644 --- a/kernel/softirq.c +++ b/kernel/softirq.c @@ -207,7 +207,7 @@ static void __local_bh_disable(unsigned long ip, unsigned int cnt) raw_local_irq_restore(flags); if (preempt_count() == cnt) - trace_preempt_off(CALLER_ADDR0, get_parent_ip(CALLER_ADDR1)); + trace_preempt_off(CALLER_ADDR0, get_lock_parent_ip()); } #else /* !CONFIG_TRACE_IRQFLAGS */ static inline void __local_bh_disable(unsigned long ip, unsigned int cnt) |