From a21ee6055c30ce68c4e201c6496f0ed2a1936230 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Mon, 25 May 2020 12:22:41 +0200 Subject: lockdep: Change hardirq{s_enabled,_context} to per-cpu variables Currently all IRQ-tracking state is in task_struct, this means that task_struct needs to be defined before we use it. Especially for lockdep_assert_irq*() this can lead to header-hell. Move the hardirq state into per-cpu variables to avoid the task_struct dependency. Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Ingo Molnar Link: https://lkml.kernel.org/r/20200623083721.512673481@infradead.org --- include/linux/irqflags.h | 19 ++++++++++++------- include/linux/lockdep.h | 34 ++++++++++++++++++---------------- include/linux/sched.h | 2 -- 3 files changed, 30 insertions(+), 25 deletions(-) (limited to 'include/linux') diff --git a/include/linux/irqflags.h b/include/linux/irqflags.h index 6384d2813ded..255444fe4609 100644 --- a/include/linux/irqflags.h +++ b/include/linux/irqflags.h @@ -14,6 +14,7 @@ #include #include +#include /* Currently lockdep_softirqs_on/off is used only by lockdep */ #ifdef CONFIG_PROVE_LOCKING @@ -31,18 +32,22 @@ #endif #ifdef CONFIG_TRACE_IRQFLAGS + +DECLARE_PER_CPU(int, hardirqs_enabled); +DECLARE_PER_CPU(int, hardirq_context); + extern void trace_hardirqs_on_prepare(void); extern void trace_hardirqs_off_finish(void); extern void trace_hardirqs_on(void); extern void trace_hardirqs_off(void); -# define lockdep_hardirq_context(p) ((p)->hardirq_context) +# define lockdep_hardirq_context(p) (this_cpu_read(hardirq_context)) # define lockdep_softirq_context(p) ((p)->softirq_context) -# define lockdep_hardirqs_enabled(p) ((p)->hardirqs_enabled) +# define lockdep_hardirqs_enabled(p) (this_cpu_read(hardirqs_enabled)) # define lockdep_softirqs_enabled(p) ((p)->softirqs_enabled) -# define lockdep_hardirq_enter() \ -do { \ - if (!current->hardirq_context++) \ - current->hardirq_threaded = 0; \ +# define lockdep_hardirq_enter() \ +do { \ + if (this_cpu_inc_return(hardirq_context) == 1) \ + current->hardirq_threaded = 0; \ } while (0) # define lockdep_hardirq_threaded() \ do { \ @@ -50,7 +55,7 @@ do { \ } while (0) # define lockdep_hardirq_exit() \ do { \ - current->hardirq_context--; \ + this_cpu_dec(hardirq_context); \ } while (0) # define lockdep_softirq_enter() \ do { \ diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h index 3b73cf84f77d..be6cb17a8879 100644 --- a/include/linux/lockdep.h +++ b/include/linux/lockdep.h @@ -11,6 +11,7 @@ #define __LINUX_LOCKDEP_H #include +#include struct task_struct; @@ -529,28 +530,29 @@ do { \ lock_release(&(lock)->dep_map, _THIS_IP_); \ } while (0) -#define lockdep_assert_irqs_enabled() do { \ - WARN_ONCE(debug_locks && !current->lockdep_recursion && \ - !current->hardirqs_enabled, \ - "IRQs not enabled as expected\n"); \ - } while (0) +DECLARE_PER_CPU(int, hardirqs_enabled); +DECLARE_PER_CPU(int, hardirq_context); -#define lockdep_assert_irqs_disabled() do { \ - WARN_ONCE(debug_locks && !current->lockdep_recursion && \ - current->hardirqs_enabled, \ - "IRQs not disabled as expected\n"); \ - } while (0) +#define lockdep_assert_irqs_enabled() \ +do { \ + WARN_ON_ONCE(debug_locks && !this_cpu_read(hardirqs_enabled)); \ +} while (0) -#define lockdep_assert_in_irq() do { \ - WARN_ONCE(debug_locks && !current->lockdep_recursion && \ - !current->hardirq_context, \ - "Not in hardirq as expected\n"); \ - } while (0) +#define lockdep_assert_irqs_disabled() \ +do { \ + WARN_ON_ONCE(debug_locks && this_cpu_read(hardirqs_enabled)); \ +} while (0) + +#define lockdep_assert_in_irq() \ +do { \ + WARN_ON_ONCE(debug_locks && !this_cpu_read(hardirq_context)); \ +} while (0) #else # define might_lock(lock) do { } while (0) # define might_lock_read(lock) do { } while (0) # define might_lock_nested(lock, subclass) do { } while (0) + # define lockdep_assert_irqs_enabled() do { } while (0) # define lockdep_assert_irqs_disabled() do { } while (0) # define lockdep_assert_in_irq() do { } while (0) @@ -560,7 +562,7 @@ do { \ # define lockdep_assert_RT_in_threaded_ctx() do { \ WARN_ONCE(debug_locks && !current->lockdep_recursion && \ - current->hardirq_context && \ + lockdep_hardirq_context(current) && \ !(current->hardirq_threaded || current->irq_config), \ "Not in threaded context on PREEMPT_RT as expected\n"); \ } while (0) diff --git a/include/linux/sched.h b/include/linux/sched.h index 692e327d7455..3903a9500926 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -990,8 +990,6 @@ struct task_struct { unsigned long hardirq_disable_ip; unsigned int hardirq_enable_event; unsigned int hardirq_disable_event; - int hardirqs_enabled; - int hardirq_context; u64 hardirq_chain_key; unsigned long softirq_disable_ip; unsigned long softirq_enable_ip; -- cgit v1.2.3