From 52baf11922db7377b580dd5448a07f71c6a35611 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Sat, 14 Feb 2009 01:15:39 -0500 Subject: [PATCH] ftrace: convert ftrace_lock from a spinlock to mutex Impact: clean up The older versions of ftrace required doing the ftrace list search under atomic context. Now all the calls are in non-atomic context. There is no reason to keep the ftrace_lock as a spinlock. This patch converts it to a mutex. Signed-off-by: Steven Rostedt --- kernel/trace/ftrace.c | 51 ++++++++++++++++--------------------------- 1 file changed, 19 insertions(+), 32 deletions(-) diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 45a44c402566..4771732037ee 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -61,7 +61,7 @@ int function_trace_stop; */ static int ftrace_disabled __read_mostly; -static DEFINE_SPINLOCK(ftrace_lock); +static DEFINE_MUTEX(ftrace_lock); static DEFINE_MUTEX(ftrace_sysctl_lock); static DEFINE_MUTEX(ftrace_start_lock); @@ -134,8 +134,7 @@ static void ftrace_test_stop_func(unsigned long ip, unsigned long parent_ip) static int __register_ftrace_function(struct ftrace_ops *ops) { - /* should not be called from interrupt context */ - spin_lock(&ftrace_lock); + mutex_lock(&ftrace_lock); ops->next = ftrace_list; /* @@ -172,7 +171,7 @@ static int __register_ftrace_function(struct ftrace_ops *ops) #endif } - spin_unlock(&ftrace_lock); + mutex_unlock(&ftrace_lock); return 0; } @@ -182,8 +181,7 @@ static int __unregister_ftrace_function(struct ftrace_ops *ops) struct ftrace_ops **p; int ret = 0; - /* should not be called from interrupt context */ - spin_lock(&ftrace_lock); + mutex_lock(&ftrace_lock); /* * If we are removing the last function, then simply point @@ -224,7 +222,7 @@ static int __unregister_ftrace_function(struct ftrace_ops *ops) } out: - spin_unlock(&ftrace_lock); + mutex_unlock(&ftrace_lock); return ret; } @@ -233,8 +231,7 @@ static void ftrace_update_pid_func(void) { ftrace_func_t func; - /* should not be called from interrupt context */ - spin_lock(&ftrace_lock); + mutex_lock(&ftrace_lock); if (ftrace_trace_function == ftrace_stub) goto out; @@ -256,7 +253,7 @@ static void ftrace_update_pid_func(void) #endif out: - spin_unlock(&ftrace_lock); + mutex_unlock(&ftrace_lock); } #ifdef CONFIG_DYNAMIC_FTRACE @@ -358,15 +355,12 @@ void ftrace_release(void *start, unsigned long size) if (ftrace_disabled || !start) return; - /* should not be called from interrupt context */ - spin_lock(&ftrace_lock); - + mutex_lock(&ftrace_lock); do_for_each_ftrace_rec(pg, rec) { if ((rec->ip >= s) && (rec->ip < e)) ftrace_free_rec(rec); } while_for_each_ftrace_rec(); - - spin_unlock(&ftrace_lock); + mutex_unlock(&ftrace_lock); } static struct dyn_ftrace *ftrace_alloc_dyn_node(unsigned long ip) @@ -803,8 +797,7 @@ t_next(struct seq_file *m, void *v, loff_t *pos) if (iter->flags & FTRACE_ITER_PRINTALL) return NULL; - /* should not be called from interrupt context */ - spin_lock(&ftrace_lock); + mutex_lock(&ftrace_lock); retry: if (iter->idx >= iter->pg->index) { if (iter->pg->next) { @@ -833,7 +826,7 @@ t_next(struct seq_file *m, void *v, loff_t *pos) goto retry; } } - spin_unlock(&ftrace_lock); + mutex_unlock(&ftrace_lock); return rec; } @@ -962,8 +955,7 @@ static void ftrace_filter_reset(int enable) struct dyn_ftrace *rec; unsigned long type = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE; - /* should not be called from interrupt context */ - spin_lock(&ftrace_lock); + mutex_lock(&ftrace_lock); if (enable) ftrace_filtered = 0; do_for_each_ftrace_rec(pg, rec) { @@ -971,8 +963,7 @@ static void ftrace_filter_reset(int enable) continue; rec->flags &= ~type; } while_for_each_ftrace_rec(); - - spin_unlock(&ftrace_lock); + mutex_unlock(&ftrace_lock); } static int @@ -1151,8 +1142,7 @@ static void ftrace_match_records(char *buff, int len, int enable) search_len = strlen(search); - /* should not be called from interrupt context */ - spin_lock(&ftrace_lock); + mutex_lock(&ftrace_lock); do_for_each_ftrace_rec(pg, rec) { if (rec->flags & FTRACE_FL_FAILED) @@ -1171,7 +1161,7 @@ static void ftrace_match_records(char *buff, int len, int enable) if (enable && (rec->flags & FTRACE_FL_FILTER)) ftrace_filtered = 1; } while_for_each_ftrace_rec(); - spin_unlock(&ftrace_lock); + mutex_unlock(&ftrace_lock); } static int @@ -1218,8 +1208,7 @@ static void ftrace_match_module_records(char *buff, char *mod, int enable) search_len = strlen(search); } - /* should not be called from interrupt context */ - spin_lock(&ftrace_lock); + mutex_lock(&ftrace_lock); do_for_each_ftrace_rec(pg, rec) { if (rec->flags & FTRACE_FL_FAILED) @@ -1236,7 +1225,7 @@ static void ftrace_match_module_records(char *buff, char *mod, int enable) ftrace_filtered = 1; } while_for_each_ftrace_rec(); - spin_unlock(&ftrace_lock); + mutex_unlock(&ftrace_lock); } /* @@ -1676,9 +1665,7 @@ ftrace_set_func(unsigned long *array, int idx, char *buffer) if (ftrace_disabled) return -ENODEV; - /* should not be called from interrupt context */ - spin_lock(&ftrace_lock); - + mutex_lock(&ftrace_lock); do_for_each_ftrace_rec(pg, rec) { if (rec->flags & (FTRACE_FL_FAILED | FTRACE_FL_FREE)) @@ -1699,7 +1686,7 @@ ftrace_set_func(unsigned long *array, int idx, char *buffer) } } while_for_each_ftrace_rec(); out: - spin_unlock(&ftrace_lock); + mutex_unlock(&ftrace_lock); return found ? 0 : -EINVAL; } -- 2.39.5