diff options
| -rw-r--r-- | kernel/trace/trace.h | 35 | ||||
| -rw-r--r-- | kernel/trace/trace_branch.c | 69 | ||||
| -rw-r--r-- | kernel/trace/trace_stat.c | 230 |
3 files changed, 217 insertions, 117 deletions
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 94ed45e93a8..b3f9ad1b4d8 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -335,6 +335,25 @@ struct tracer_flags { #define TRACER_OPT(s, b) .name = #s, .bit = b /* + * If you want to provide a stat file (one-shot statistics), fill + * an iterator with stat_start/stat_next and a stat_show callbacks. + * The others callbacks are optional. + */ +struct tracer_stat { + /* The name of your stat file */ + const char *name; + /* Iteration over statistic entries */ + void *(*stat_start)(void); + void *(*stat_next)(void *prev, int idx); + /* Compare two entries for sorting (optional) for stats */ + int (*stat_cmp)(void *p1, void *p2); + /* Print a stat entry */ + int (*stat_show)(struct seq_file *s, void *p); + /* Print the headers of your stat entries */ + int (*stat_headers)(struct seq_file *s); +}; + +/* * A specific tracer, represented by methods that operate on a trace array: */ struct tracer { @@ -361,21 +380,7 @@ struct tracer { struct tracer *next; int print_max; struct tracer_flags *flags; - - /* - * If you change one of the following on tracing runtime, recall - * init_tracer_stat() - */ - - /* Iteration over statistic entries */ - void *(*stat_start)(void); - void *(*stat_next)(void *prev, int idx); - /* Compare two entries for sorting (optional) for stats */ - int (*stat_cmp)(void *p1, void *p2); - /* Print a stat entry */ - int (*stat_show)(struct seq_file *s, void *p); - /* Print the headers of your stat entries */ - int (*stat_headers)(struct seq_file *s); + struct tracer_stat *stats; }; struct trace_seq { diff --git a/kernel/trace/trace_branch.c b/kernel/trace/trace_branch.c index 4785a3b9bc4..da5cf3e5581 100644 --- a/kernel/trace/trace_branch.c +++ b/kernel/trace/trace_branch.c @@ -306,19 +306,6 @@ static int annotated_branch_stat_cmp(void *p1, void *p2) } #ifdef CONFIG_PROFILE_ALL_BRANCHES -enum { - TRACE_BRANCH_OPT_ALL = 0x1 -}; - -static struct tracer_opt branch_opts[] = { - { TRACER_OPT(stat_all_branch, TRACE_BRANCH_OPT_ALL) }, - { } -}; - -static struct tracer_flags branch_flags = { - .val = 0, - .opts = branch_opts -}; extern unsigned long __start_branch_profile[]; extern unsigned long __stop_branch_profile[]; @@ -352,28 +339,36 @@ all_branch_stat_next(void *v, int idx) return p; } -static int branch_set_flag(u32 old_flags, u32 bit, int set) -{ - if (bit == TRACE_BRANCH_OPT_ALL) { - if (set) { - branch_trace.stat_headers = all_branch_stat_headers; - branch_trace.stat_start = all_branch_stat_start; - branch_trace.stat_next = all_branch_stat_next; - branch_trace.stat_cmp = NULL; - } else { - branch_trace.stat_headers = - annotated_branch_stat_headers; - branch_trace.stat_start = annotated_branch_stat_start; - branch_trace.stat_next = annotated_branch_stat_next; - branch_trace.stat_cmp = annotated_branch_stat_cmp; - } - init_tracer_stat(&branch_trace); - } - return 0; -} +static struct tracer_stat branch_stats[] = { + {.name = "annotated", + .stat_start = annotated_branch_stat_start, + .stat_next = annotated_branch_stat_next, + .stat_cmp = annotated_branch_stat_cmp, + .stat_headers = annotated_branch_stat_headers, + .stat_show = branch_stat_show}, + {.name = "all", + .stat_start = all_branch_stat_start, + .stat_next = all_branch_stat_next, + .stat_headers = all_branch_stat_headers, + .stat_show = branch_stat_show}, + + { } +}; +#else +static struct tracer_stat branch_stats[] = { + {.name = "annotated", + .stat_start = annotated_branch_stat_start, + .stat_next = annotated_branch_stat_next, + .stat_cmp = annotated_branch_stat_cmp, + .stat_headers = annotated_branch_stat_headers, + .stat_show = branch_stat_show}, + + { } +}; #endif /* CONFIG_PROFILE_ALL_BRANCHES */ + static struct tracer branch_trace __read_mostly = { .name = "branch", @@ -383,16 +378,8 @@ static struct tracer branch_trace __read_mostly = #ifdef CONFIG_FTRACE_SELFTEST .selftest = trace_selftest_startup_branch, #endif /* CONFIG_FTRACE_SELFTEST */ -#endif /* CONFIG_BRANCH_TRACER */ - .stat_start = annotated_branch_stat_start, - .stat_next = annotated_branch_stat_next, - .stat_show = branch_stat_show, - .stat_headers = annotated_branch_stat_headers, - .stat_cmp = annotated_branch_stat_cmp, -#ifdef CONFIG_PROFILE_ALL_BRANCHES - .flags = &branch_flags, - .set_flag = branch_set_flag, #endif + .stats = branch_stats }; __init static int init_branch_trace(void) diff --git a/kernel/trace/trace_stat.c b/kernel/trace/trace_stat.c index f110ce9ce7f..1515f9e7adf 100644 --- a/kernel/trace/trace_stat.c +++ b/kernel/trace/trace_stat.c @@ -21,37 +21,87 @@ struct trace_stat_list { void *stat; }; -static LIST_HEAD(stat_list); - -/* - * This is a copy of the current tracer to avoid racy - * and dangerous output while the current tracer is - * switched. - */ -static struct tracer current_tracer; +/* A stat session is the stats output in one file */ +struct tracer_stat_session { + struct tracer_stat *ts; + struct list_head stat_list; + struct mutex stat_mutex; +}; -/* - * Protect both the current tracer and the global - * stat list. - */ -static DEFINE_MUTEX(stat_list_mutex); +/* All of the sessions currently in use. Each stat file embeed one session */ +static struct tracer_stat_session **all_stat_sessions; +static int nb_sessions; +static struct dentry *stat_dir, **stat_files; -static void reset_stat_list(void) +static void reset_stat_session(struct tracer_stat_session *session) { struct trace_stat_list *node, *next; - list_for_each_entry_safe(node, next, &stat_list, list) + list_for_each_entry_safe(node, next, &session->stat_list, list) kfree(node); - INIT_LIST_HEAD(&stat_list); + INIT_LIST_HEAD(&session->stat_list); } -void init_tracer_stat(struct tracer *trace) +/* Called when a tracer is initialized */ +static int init_all_sessions(int nb, struct tracer_stat *ts) { - mutex_lock(&stat_list_mutex); - current_tracer = *trace; - mutex_unlock(&stat_list_mutex); + int i, j; + struct tracer_stat_session *session; + + nb_sessions = 0; + + if (all_stat_sessions) { + for (i = 0; i < nb_sessions; i++) { + session = all_stat_sessions[i]; + reset_stat_session(session); + mutex_destroy(&session->stat_mutex); + kfree(session); + } + } + all_stat_sessions = kmalloc(sizeof(struct tracer_stat_session *) * nb, + GFP_KERNEL); + if (!all_stat_sessions) + return -ENOMEM; + + for (i = 0; i < nb; i++) { + session = kmalloc(sizeof(struct tracer_stat_session) * nb, + GFP_KERNEL); + if (!session) + goto free_sessions; + + INIT_LIST_HEAD(&session->stat_list); + mutex_init(&session->stat_mutex); + session->ts = &ts[i]; + all_stat_sessions[i] = session; + } + nb_sessions = nb; + return 0; + +free_sessions: + + for (j = 0; j < i; j++) + kfree(all_stat_sessions[i]); + + kfree(all_stat_sessions); + all_stat_sessions = NULL; + + return -ENOMEM; +} + +static int basic_tracer_stat_checks(struct tracer_stat *ts) +{ + int i; + + if (!ts) + return 0; + + for (i = 0; ts[i].name; i++) { + if (!ts[i].stat_start || !ts[i].stat_next || !ts[i].stat_show) + return -EBUSY; + } + return i; } /* @@ -69,22 +119,19 @@ static int dummy_cmp(void *p1, void *p2) * All of these copies and sorting are required on all opening * since the stats could have changed between two file sessions. */ -static int stat_seq_init(void) +static int stat_seq_init(struct tracer_stat_session *session) { struct trace_stat_list *iter_entry, *new_entry; + struct tracer_stat *ts = session->ts; void *prev_stat; int ret = 0; int i; - mutex_lock(&stat_list_mutex); - reset_stat_list(); - - if (!current_tracer.stat_start || !current_tracer.stat_next || - !current_tracer.stat_show) - goto exit; + mutex_lock(&session->stat_mutex); + reset_stat_session(session); - if (!current_tracer.stat_cmp) - current_tracer.stat_cmp = dummy_cmp; + if (!ts->stat_cmp) + ts->stat_cmp = dummy_cmp; /* * The first entry. Actually this is the second, but the first @@ -97,9 +144,10 @@ static int stat_seq_init(void) } INIT_LIST_HEAD(&new_entry->list); - list_add(&new_entry->list, &stat_list); - new_entry->stat = current_tracer.stat_start(); + list_add(&new_entry->list, &session->stat_list); + + new_entry->stat = ts->stat_start(); prev_stat = new_entry->stat; /* @@ -114,15 +162,16 @@ static int stat_seq_init(void) } INIT_LIST_HEAD(&new_entry->list); - new_entry->stat = current_tracer.stat_next(prev_stat, i); + new_entry->stat = ts->stat_next(prev_stat, i); /* End of insertion */ if (!new_entry->stat) break; - list_for_each_entry(iter_entry, &stat_list, list) { + list_for_each_entry(iter_entry, &session->stat_list, list) { + /* Insertion with a descendent sorting */ - if (current_tracer.stat_cmp(new_entry->stat, + if (ts->stat_cmp(new_entry->stat, iter_entry->stat) > 0) { list_add_tail(&new_entry->list, @@ -131,7 +180,7 @@ static int stat_seq_init(void) /* The current smaller value */ } else if (list_is_last(&iter_entry->list, - &stat_list)) { + &session->stat_list)) { list_add(&new_entry->list, &iter_entry->list); break; } @@ -140,49 +189,49 @@ static int stat_seq_init(void) prev_stat = new_entry->stat; } exit: - mutex_unlock(&stat_list_mutex); + mutex_unlock(&session->stat_mutex); return ret; exit_free_list: - reset_stat_list(); - mutex_unlock(&stat_list_mutex); + reset_stat_session(session); + mutex_unlock(&session->stat_mutex); return ret; } static void *stat_seq_start(struct seq_file *s, loff_t *pos) { - struct list_head *l = (struct list_head *)s->private; + struct tracer_stat_session *session = s->private; /* Prevent from tracer switch or stat_list modification */ - mutex_lock(&stat_list_mutex); + mutex_lock(&session->stat_mutex); /* If we are in the beginning of the file, print the headers */ - if (!*pos && current_tracer.stat_headers) - current_tracer.stat_headers(s); + if (!*pos && session->ts->stat_headers) + session->ts->stat_headers(s); - return seq_list_start(l, *pos); + return seq_list_start(&session->stat_list, *pos); } static void *stat_seq_next(struct seq_file *s, void *p, loff_t *pos) { - struct list_head *l = (struct list_head *)s->private; + struct tracer_stat_session *session = s->private; - return seq_list_next(p, l, pos); + return seq_list_next(p, &session->stat_list, pos); } -static void stat_seq_stop(struct seq_file *m, void *p) +static void stat_seq_stop(struct seq_file *s, void *p) { - mutex_unlock(&stat_list_mutex); + struct tracer_stat_session *session = s->private; + mutex_unlock(&session->stat_mutex); } static int stat_seq_show(struct seq_file *s, void *v) { - struct trace_stat_list *entry; - - entry = list_entry(v, struct trace_stat_list, list); + struct tracer_stat_session *session = s->private; + struct trace_stat_list *l = list_entry(v, struct trace_stat_list, list); - return current_tracer.stat_show(s, entry->stat); + return session->ts->stat_show(s, l->stat); } static const struct seq_operations trace_stat_seq_ops = { @@ -192,15 +241,18 @@ static const struct seq_operations trace_stat_seq_ops = { .show = stat_seq_show }; +/* The session stat is refilled and resorted at each stat file opening */ static int tracing_stat_open(struct inode *inode, struct file *file) { int ret; + struct tracer_stat_session *session = inode->i_private; + ret = seq_open(file, &trace_stat_seq_ops); if (!ret) { struct seq_file *m = file->private_data; - m->private = &stat_list; - ret = stat_seq_init(); + m->private = session; + ret = stat_seq_init(session); } return ret; @@ -212,9 +264,12 @@ static int tracing_stat_open(struct inode *inode, struct file *file) */ static int tracing_stat_release(struct inode *i, struct file *f) { - mutex_lock(&stat_list_mutex); - reset_stat_list(); - mutex_unlock(&stat_list_mutex); + struct tracer_stat_session *session = i->i_private; + + mutex_lock(&session->stat_mutex); + reset_stat_session(session); + mutex_unlock(&session->stat_mutex); + return 0; } @@ -225,17 +280,70 @@ static const struct file_operations tracing_stat_fops = { .release = tracing_stat_release }; + +static void destroy_trace_stat_files(void) +{ + int i; + + if (stat_files) { + for (i = 0; i < nb_sessions; i++) + debugfs_remove(stat_files[i]); + kfree(stat_files); + stat_files = NULL; + } +} + +static void init_trace_stat_files(void) +{ + int i; + + if (!stat_dir || !nb_sessions) + return; + + stat_files = kmalloc(sizeof(struct dentry *) * nb_sessions, GFP_KERNEL); + + if (!stat_files) { + pr_warning("trace stat: not enough memory\n"); + return; + } + + for (i = 0; i < nb_sessions; i++) { + struct tracer_stat_session *session = all_stat_sessions[i]; + stat_files[i] = debugfs_create_file(session->ts->name, 0644, + stat_dir, + session, &tracing_stat_fops); + if (!stat_files[i]) + pr_warning("cannot create %s entry\n", + session->ts->name); + } +} + +void init_tracer_stat(struct tracer *trace) +{ + int nb = basic_tracer_stat_checks(trace->stats); + + destroy_trace_stat_files(); + + if (nb < 0) { + pr_warning("stat tracing: missing stat callback on %s\n", + trace->name); + return; + } + if (!nb) + return; + + init_all_sessions(nb, trace->stats); + init_trace_stat_files(); +} + static int __init tracing_stat_init(void) { struct dentry *d_tracing; - struct dentry *entry; d_tracing = tracing_init_dentry(); - entry = debugfs_create_file("trace_stat", 0444, d_tracing, - NULL, - &tracing_stat_fops); - if (!entry) + stat_dir = debugfs_create_dir("trace_stat", d_tracing); + if (!stat_dir) pr_warning("Could not create debugfs " "'trace_stat' entry\n"); return 0; |