[PATCH RT 6/8] sched: Better debug output for might sleep
From: Thomas Gleixner
might sleep can tell us where interrupts have been disabled, but we
have no idea what disabled preemption. Add some debug infrastructure.
Cc: stable...@vger.kernel.org
Signed-off-by: Thomas Gleixner
Signed-off-by: Steven Rostedt
---
include/linux/sched.h |4
kernel/sched.c| 23 +--
2 files changed, 25 insertions(+), 2 deletions(-)
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 03498cc..12317b6 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1612,6 +1612,10 @@ struct task_struct {
int kmap_idx;
pte_t kmap_pte[KM_TYPE_NR];
#endif
+
+#ifdef CONFIG_DEBUG_PREEMPT
+ unsigned long preempt_disable_ip;
+#endif
};
#ifdef CONFIG_PREEMPT_RT_FULL
diff --git a/kernel/sched.c b/kernel/sched.c
index 87654e6..cdf9484 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -4487,8 +4487,13 @@ void __kprobes add_preempt_count(int val)
DEBUG_LOCKS_WARN_ON((preempt_count() & PREEMPT_MASK) >=
PREEMPT_MASK - 10);
#endif
- if (preempt_count() == val)
- trace_preempt_off(CALLER_ADDR0, get_parent_ip(CALLER_ADDR1));
+ if (preempt_count() == val) {
+ unsigned long ip = get_parent_ip(CALLER_ADDR1);
+#ifdef CONFIG_DEBUG_PREEMPT
+ current->preempt_disable_ip = ip;
+#endif
+ trace_preempt_off(CALLER_ADDR0, ip);
+ }
}
EXPORT_SYMBOL(add_preempt_count);
@@ -4530,6 +4535,13 @@ static noinline void __schedule_bug(struct task_struct
*prev)
print_modules();
if (irqs_disabled())
print_irqtrace_events(prev);
+#ifdef DEBUG_PREEMPT
+ if (in_atomic_preempt_off()) {
+ pr_err("Preemption disabled at:");
+ print_ip_sym(current->preempt_disable_ip);
+ pr_cont("\n");
+ }
+#endif
if (regs)
show_regs(regs);
@@ -8912,6 +8924,13 @@ void __might_sleep(const char *file, int line, int
preempt_offset)
debug_show_held_locks(current);
if (irqs_disabled())
print_irqtrace_events(current);
+#ifdef DEBUG_PREEMPT
+ if (!preempt_count_equals(preempt_offset)) {
+ pr_err("Preemption disabled at:");
+ print_ip_sym(current->preempt_disable_ip);
+ pr_cont("\n");
+ }
+#endif
dump_stack();
}
EXPORT_SYMBOL(__might_sleep);
--
1.7.10.4
--
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[PATCH RT 6/8] sched: Better debug output for might sleep
From: Thomas Gleixner t...@linutronix.de
might sleep can tell us where interrupts have been disabled, but we
have no idea what disabled preemption. Add some debug infrastructure.
Cc: stable...@vger.kernel.org
Signed-off-by: Thomas Gleixner t...@linutronix.de
Signed-off-by: Steven Rostedt rost...@goodmis.org
---
include/linux/sched.h |4
kernel/sched.c| 23 +--
2 files changed, 25 insertions(+), 2 deletions(-)
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 03498cc..12317b6 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1612,6 +1612,10 @@ struct task_struct {
int kmap_idx;
pte_t kmap_pte[KM_TYPE_NR];
#endif
+
+#ifdef CONFIG_DEBUG_PREEMPT
+ unsigned long preempt_disable_ip;
+#endif
};
#ifdef CONFIG_PREEMPT_RT_FULL
diff --git a/kernel/sched.c b/kernel/sched.c
index 87654e6..cdf9484 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -4487,8 +4487,13 @@ void __kprobes add_preempt_count(int val)
DEBUG_LOCKS_WARN_ON((preempt_count() PREEMPT_MASK) =
PREEMPT_MASK - 10);
#endif
- if (preempt_count() == val)
- trace_preempt_off(CALLER_ADDR0, get_parent_ip(CALLER_ADDR1));
+ if (preempt_count() == val) {
+ unsigned long ip = get_parent_ip(CALLER_ADDR1);
+#ifdef CONFIG_DEBUG_PREEMPT
+ current-preempt_disable_ip = ip;
+#endif
+ trace_preempt_off(CALLER_ADDR0, ip);
+ }
}
EXPORT_SYMBOL(add_preempt_count);
@@ -4530,6 +4535,13 @@ static noinline void __schedule_bug(struct task_struct
*prev)
print_modules();
if (irqs_disabled())
print_irqtrace_events(prev);
+#ifdef DEBUG_PREEMPT
+ if (in_atomic_preempt_off()) {
+ pr_err(Preemption disabled at:);
+ print_ip_sym(current-preempt_disable_ip);
+ pr_cont(\n);
+ }
+#endif
if (regs)
show_regs(regs);
@@ -8912,6 +8924,13 @@ void __might_sleep(const char *file, int line, int
preempt_offset)
debug_show_held_locks(current);
if (irqs_disabled())
print_irqtrace_events(current);
+#ifdef DEBUG_PREEMPT
+ if (!preempt_count_equals(preempt_offset)) {
+ pr_err(Preemption disabled at:);
+ print_ip_sym(current-preempt_disable_ip);
+ pr_cont(\n);
+ }
+#endif
dump_stack();
}
EXPORT_SYMBOL(__might_sleep);
--
1.7.10.4
--
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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/
[PATCH RT 6/8] sched: Better debug output for might sleep
From: Thomas Gleixner
might sleep can tell us where interrupts have been disabled, but we
have no idea what disabled preemption. Add some debug infrastructure.
Cc: stable...@vger.kernel.org
Signed-off-by: Thomas Gleixner
Signed-off-by: Steven Rostedt
---
include/linux/sched.h |4
kernel/sched/core.c | 23 +--
2 files changed, 25 insertions(+), 2 deletions(-)
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 6f342d8..f291347 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1655,6 +1655,10 @@ struct task_struct {
int kmap_idx;
pte_t kmap_pte[KM_TYPE_NR];
#endif
+
+#ifdef CONFIG_DEBUG_PREEMPT
+ unsigned long preempt_disable_ip;
+#endif
};
#ifdef CONFIG_PREEMPT_RT_FULL
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 66d4dea..263fd96 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -3215,8 +3215,13 @@ void __kprobes add_preempt_count(int val)
DEBUG_LOCKS_WARN_ON((preempt_count() & PREEMPT_MASK) >=
PREEMPT_MASK - 10);
#endif
- if (preempt_count() == val)
- trace_preempt_off(CALLER_ADDR0, get_parent_ip(CALLER_ADDR1));
+ if (preempt_count() == val) {
+ unsigned long ip = get_parent_ip(CALLER_ADDR1);
+#ifdef CONFIG_DEBUG_PREEMPT
+ current->preempt_disable_ip = ip;
+#endif
+ trace_preempt_off(CALLER_ADDR0, ip);
+ }
}
EXPORT_SYMBOL(add_preempt_count);
@@ -3259,6 +3264,13 @@ static noinline void __schedule_bug(struct task_struct
*prev)
print_modules();
if (irqs_disabled())
print_irqtrace_events(prev);
+#ifdef DEBUG_PREEMPT
+ if (in_atomic_preempt_off()) {
+ pr_err("Preemption disabled at:");
+ print_ip_sym(current->preempt_disable_ip);
+ pr_cont("\n");
+ }
+#endif
dump_stack();
}
@@ -7479,6 +7491,13 @@ void __might_sleep(const char *file, int line, int
preempt_offset)
debug_show_held_locks(current);
if (irqs_disabled())
print_irqtrace_events(current);
+#ifdef DEBUG_PREEMPT
+ if (!preempt_count_equals(preempt_offset)) {
+ pr_err("Preemption disabled at:");
+ print_ip_sym(current->preempt_disable_ip);
+ pr_cont("\n");
+ }
+#endif
dump_stack();
}
EXPORT_SYMBOL(__might_sleep);
--
1.7.10.4
--
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/
[PATCH RT 6/8] sched: Better debug output for might sleep
From: Thomas Gleixner t...@linutronix.de
might sleep can tell us where interrupts have been disabled, but we
have no idea what disabled preemption. Add some debug infrastructure.
Cc: stable...@vger.kernel.org
Signed-off-by: Thomas Gleixner t...@linutronix.de
Signed-off-by: Steven Rostedt rost...@goodmis.org
---
include/linux/sched.h |4
kernel/sched/core.c | 23 +--
2 files changed, 25 insertions(+), 2 deletions(-)
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 6f342d8..f291347 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1655,6 +1655,10 @@ struct task_struct {
int kmap_idx;
pte_t kmap_pte[KM_TYPE_NR];
#endif
+
+#ifdef CONFIG_DEBUG_PREEMPT
+ unsigned long preempt_disable_ip;
+#endif
};
#ifdef CONFIG_PREEMPT_RT_FULL
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 66d4dea..263fd96 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -3215,8 +3215,13 @@ void __kprobes add_preempt_count(int val)
DEBUG_LOCKS_WARN_ON((preempt_count() PREEMPT_MASK) =
PREEMPT_MASK - 10);
#endif
- if (preempt_count() == val)
- trace_preempt_off(CALLER_ADDR0, get_parent_ip(CALLER_ADDR1));
+ if (preempt_count() == val) {
+ unsigned long ip = get_parent_ip(CALLER_ADDR1);
+#ifdef CONFIG_DEBUG_PREEMPT
+ current-preempt_disable_ip = ip;
+#endif
+ trace_preempt_off(CALLER_ADDR0, ip);
+ }
}
EXPORT_SYMBOL(add_preempt_count);
@@ -3259,6 +3264,13 @@ static noinline void __schedule_bug(struct task_struct
*prev)
print_modules();
if (irqs_disabled())
print_irqtrace_events(prev);
+#ifdef DEBUG_PREEMPT
+ if (in_atomic_preempt_off()) {
+ pr_err(Preemption disabled at:);
+ print_ip_sym(current-preempt_disable_ip);
+ pr_cont(\n);
+ }
+#endif
dump_stack();
}
@@ -7479,6 +7491,13 @@ void __might_sleep(const char *file, int line, int
preempt_offset)
debug_show_held_locks(current);
if (irqs_disabled())
print_irqtrace_events(current);
+#ifdef DEBUG_PREEMPT
+ if (!preempt_count_equals(preempt_offset)) {
+ pr_err(Preemption disabled at:);
+ print_ip_sym(current-preempt_disable_ip);
+ pr_cont(\n);
+ }
+#endif
dump_stack();
}
EXPORT_SYMBOL(__might_sleep);
--
1.7.10.4
--
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/
