The one and only user of FTRACE_OPS_FL_PER_CPU is gone, remove the lot. Signed-off-by: Peter Zijlstra (Intel) --- include/linux/ftrace.h | 57 +------------------------------------------------ kernel/trace/ftrace.c | 55 +++++------------------------------------------ 2 files changed, 8 insertions(+), 104 deletions(-) --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -78,10 +78,7 @@ ftrace_func_t ftrace_ops_get_func(struct * ENABLED - set/unset when ftrace_ops is registered/unregistered * DYNAMIC - set when ftrace_ops is registered to denote dynamically * allocated ftrace_ops which need special care - * PER_CPU - set manualy by ftrace_ops user to denote the ftrace_ops - * could be controlled by following calls: - * ftrace_function_local_enable - * ftrace_function_local_disable + * * SAVE_REGS - The ftrace_ops wants regs saved at each function called * and passed to the callback. If this flag is set, but the * architecture does not support passing regs @@ -125,7 +122,7 @@ ftrace_func_t ftrace_ops_get_func(struct enum { FTRACE_OPS_FL_ENABLED = 1 << 0, FTRACE_OPS_FL_DYNAMIC = 1 << 1, - FTRACE_OPS_FL_PER_CPU = 1 << 2, + FTRACE_OPS_FL_SAVE_REGS = 1 << 3, FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED = 1 << 4, FTRACE_OPS_FL_RECURSION_SAFE = 1 << 5, @@ -172,7 +169,6 @@ struct ftrace_ops { unsigned long flags; void *private; ftrace_func_t saved_func; - int __percpu *disabled; #ifdef CONFIG_DYNAMIC_FTRACE struct ftrace_ops_hash local_hash; struct ftrace_ops_hash *func_hash; @@ -204,55 +200,6 @@ int register_ftrace_function(struct ftra int unregister_ftrace_function(struct ftrace_ops *ops); void clear_ftrace_function(void); -/** - * ftrace_function_local_enable - enable ftrace_ops on current cpu - * - * This function enables tracing on current cpu by decreasing - * the per cpu control variable. - * It must be called with preemption disabled and only on ftrace_ops - * registered with FTRACE_OPS_FL_PER_CPU. If called without preemption - * disabled, this_cpu_ptr will complain when CONFIG_DEBUG_PREEMPT is enabled. - */ -static inline void ftrace_function_local_enable(struct ftrace_ops *ops) -{ - if (WARN_ON_ONCE(!(ops->flags & FTRACE_OPS_FL_PER_CPU))) - return; - - (*this_cpu_ptr(ops->disabled))--; -} - -/** - * ftrace_function_local_disable - disable ftrace_ops on current cpu - * - * This function disables tracing on current cpu by increasing - * the per cpu control variable. - * It must be called with preemption disabled and only on ftrace_ops - * registered with FTRACE_OPS_FL_PER_CPU. If called without preemption - * disabled, this_cpu_ptr will complain when CONFIG_DEBUG_PREEMPT is enabled. - */ -static inline void ftrace_function_local_disable(struct ftrace_ops *ops) -{ - if (WARN_ON_ONCE(!(ops->flags & FTRACE_OPS_FL_PER_CPU))) - return; - - (*this_cpu_ptr(ops->disabled))++; -} - -/** - * ftrace_function_local_disabled - returns ftrace_ops disabled value - * on current cpu - * - * This function returns value of ftrace_ops::disabled on current cpu. - * It must be called with preemption disabled and only on ftrace_ops - * registered with FTRACE_OPS_FL_PER_CPU. If called without preemption - * disabled, this_cpu_ptr will complain when CONFIG_DEBUG_PREEMPT is enabled. - */ -static inline int ftrace_function_local_disabled(struct ftrace_ops *ops) -{ - WARN_ON_ONCE(!(ops->flags & FTRACE_OPS_FL_PER_CPU)); - return *this_cpu_ptr(ops->disabled); -} - extern void ftrace_stub(unsigned long a0, unsigned long a1, struct ftrace_ops *op, struct pt_regs *regs); --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -203,30 +203,6 @@ void clear_ftrace_function(void) ftrace_trace_function = ftrace_stub; } -static void per_cpu_ops_disable_all(struct ftrace_ops *ops) -{ - int cpu; - - for_each_possible_cpu(cpu) - *per_cpu_ptr(ops->disabled, cpu) = 1; -} - -static int per_cpu_ops_alloc(struct ftrace_ops *ops) -{ - int __percpu *disabled; - - if (WARN_ON_ONCE(!(ops->flags & FTRACE_OPS_FL_PER_CPU))) - return -EINVAL; - - disabled = alloc_percpu(int); - if (!disabled) - return -ENOMEM; - - ops->disabled = disabled; - per_cpu_ops_disable_all(ops); - return 0; -} - static void ftrace_sync(struct work_struct *work) { /* @@ -262,8 +238,8 @@ static ftrace_func_t ftrace_ops_get_list * If this is a dynamic, RCU, or per CPU ops, or we force list func, * then it needs to call the list anyway. */ - if (ops->flags & (FTRACE_OPS_FL_DYNAMIC | FTRACE_OPS_FL_PER_CPU | - FTRACE_OPS_FL_RCU) || FTRACE_FORCE_LIST_FUNC) + if (ops->flags & (FTRACE_OPS_FL_DYNAMIC | FTRACE_OPS_FL_RCU) || + FTRACE_FORCE_LIST_FUNC) return ftrace_ops_list_func; return ftrace_ops_get_func(ops); @@ -422,11 +398,6 @@ static int __register_ftrace_function(st if (!core_kernel_data((unsigned long)ops)) ops->flags |= FTRACE_OPS_FL_DYNAMIC; - if (ops->flags & FTRACE_OPS_FL_PER_CPU) { - if (per_cpu_ops_alloc(ops)) - return -ENOMEM; - } - add_ftrace_ops(&ftrace_ops_list, ops); /* Always save the function, and reset at unregistering */ @@ -2727,11 +2698,6 @@ void __weak arch_ftrace_trampoline_free( { } -static void per_cpu_ops_free(struct ftrace_ops *ops) -{ - free_percpu(ops->disabled); -} - static void ftrace_startup_enable(int command) { if (saved_ftrace_func != ftrace_trace_function) { @@ -2833,7 +2799,7 @@ static int ftrace_shutdown(struct ftrace * not currently active, we can just free them * without synchronizing all CPUs. */ - if (ops->flags & (FTRACE_OPS_FL_DYNAMIC | FTRACE_OPS_FL_PER_CPU)) + if (ops->flags & FTRACE_OPS_FL_DYNAMIC) goto free_ops; return 0; @@ -2880,7 +2846,7 @@ static int ftrace_shutdown(struct ftrace * The same goes for freeing the per_cpu data of the per_cpu * ops. */ - if (ops->flags & (FTRACE_OPS_FL_DYNAMIC | FTRACE_OPS_FL_PER_CPU)) { + if (ops->flags & (FTRACE_OPS_FL_DYNAMIC)) { /* * We need to do a hard force of sched synchronization. * This is because we use preempt_disable() to do RCU, but @@ -2903,9 +2869,6 @@ static int ftrace_shutdown(struct ftrace free_ops: arch_ftrace_trampoline_free(ops); - - if (ops->flags & FTRACE_OPS_FL_PER_CPU) - per_cpu_ops_free(ops); } return 0; @@ -6066,10 +6029,7 @@ __ftrace_ops_list_func(unsigned long ip, * If any of the above fails then the op->func() is not executed. */ if ((!(op->flags & FTRACE_OPS_FL_RCU) || rcu_is_watching()) && - (!(op->flags & FTRACE_OPS_FL_PER_CPU) || - !ftrace_function_local_disabled(op)) && ftrace_ops_test(op, ip, regs)) { - if (FTRACE_WARN_ON(!op->func)) { pr_warn("op=%p %pS\n", op, op); goto out; @@ -6127,10 +6087,7 @@ static void ftrace_ops_assist_func(unsig preempt_disable_notrace(); - if (!(op->flags & FTRACE_OPS_FL_PER_CPU) || - !ftrace_function_local_disabled(op)) { - op->func(ip, parent_ip, op, regs); - } + op->func(ip, parent_ip, op, regs); preempt_enable_notrace(); trace_clear_recursion(bit); @@ -6154,7 +6111,7 @@ ftrace_func_t ftrace_ops_get_func(struct * or does per cpu logic, then we need to call the assist handler. */ if (!(ops->flags & FTRACE_OPS_FL_RECURSION_SAFE) || - ops->flags & (FTRACE_OPS_FL_RCU | FTRACE_OPS_FL_PER_CPU)) + ops->flags & FTRACE_OPS_FL_RCU) return ftrace_ops_assist_func; return ops->func;