#include <linux/list.h>
#include <linux/hash.h>
+#include <trace/events/sched.h>
+
#include <asm/ftrace.h>
+#include <asm/setup.h>
-#include "trace.h"
+#include "trace_output.h"
+#include "trace_stat.h"
#define FTRACE_WARN_ON(cond) \
do { \
/* Quick disabling of function tracer. */
int function_trace_stop;
+/* List for set_ftrace_pid's pids. */
+LIST_HEAD(ftrace_pids);
+struct ftrace_pid {
+ struct list_head list;
+ struct pid *pid;
+};
+
/*
* ftrace_disabled is set when an anomaly is discovered.
* ftrace_disabled is much stronger than ftrace_enabled.
static struct ftrace_ops ftrace_list_end __read_mostly =
{
- .func = ftrace_stub,
+ .func = ftrace_stub,
};
static struct ftrace_ops *ftrace_list __read_mostly = &ftrace_list_end;
ftrace_func_t __ftrace_trace_function __read_mostly = ftrace_stub;
ftrace_func_t ftrace_pid_function __read_mostly = ftrace_stub;
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+static int ftrace_set_func(unsigned long *array, int *idx, char *buffer);
+#endif
+
static void ftrace_list_func(unsigned long ip, unsigned long parent_ip)
{
struct ftrace_ops *op = ftrace_list;
else
func = ftrace_list_func;
- if (ftrace_pid_trace) {
+ if (!list_empty(&ftrace_pids)) {
set_ftrace_pid_function(func);
func = ftrace_pid_func;
}
if (ftrace_list->next == &ftrace_list_end) {
ftrace_func_t func = ftrace_list->func;
- if (ftrace_pid_trace) {
+ if (!list_empty(&ftrace_pids)) {
set_ftrace_pid_function(func);
func = ftrace_pid_func;
}
if (ftrace_trace_function == ftrace_stub)
return;
+#ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST
func = ftrace_trace_function;
+#else
+ func = __ftrace_trace_function;
+#endif
- if (ftrace_pid_trace) {
+ if (!list_empty(&ftrace_pids)) {
set_ftrace_pid_function(func);
func = ftrace_pid_func;
} else {
#endif
}
-/* set when tracing only a pid */
-struct pid *ftrace_pid_trace;
+#ifdef CONFIG_FUNCTION_PROFILER
+struct ftrace_profile {
+ struct hlist_node node;
+ unsigned long ip;
+ unsigned long counter;
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+ unsigned long long time;
+#endif
+};
+
+struct ftrace_profile_page {
+ struct ftrace_profile_page *next;
+ unsigned long index;
+ struct ftrace_profile records[];
+};
+
+struct ftrace_profile_stat {
+ atomic_t disabled;
+ struct hlist_head *hash;
+ struct ftrace_profile_page *pages;
+ struct ftrace_profile_page *start;
+ struct tracer_stat stat;
+};
+
+#define PROFILE_RECORDS_SIZE \
+ (PAGE_SIZE - offsetof(struct ftrace_profile_page, records))
+
+#define PROFILES_PER_PAGE \
+ (PROFILE_RECORDS_SIZE / sizeof(struct ftrace_profile))
+
+static int ftrace_profile_bits __read_mostly;
+static int ftrace_profile_enabled __read_mostly;
+
+/* ftrace_profile_lock - synchronize the enable and disable of the profiler */
+static DEFINE_MUTEX(ftrace_profile_lock);
+
+static DEFINE_PER_CPU(struct ftrace_profile_stat, ftrace_profile_stats);
+
+#define FTRACE_PROFILE_HASH_SIZE 1024 /* must be power of 2 */
+
+static void *
+function_stat_next(void *v, int idx)
+{
+ struct ftrace_profile *rec = v;
+ struct ftrace_profile_page *pg;
+
+ pg = (struct ftrace_profile_page *)((unsigned long)rec & PAGE_MASK);
+
+ again:
+ if (idx != 0)
+ rec++;
+
+ if ((void *)rec >= (void *)&pg->records[pg->index]) {
+ pg = pg->next;
+ if (!pg)
+ return NULL;
+ rec = &pg->records[0];
+ if (!rec->counter)
+ goto again;
+ }
+
+ return rec;
+}
+
+static void *function_stat_start(struct tracer_stat *trace)
+{
+ struct ftrace_profile_stat *stat =
+ container_of(trace, struct ftrace_profile_stat, stat);
+
+ if (!stat || !stat->start)
+ return NULL;
+
+ return function_stat_next(&stat->start->records[0], 0);
+}
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+/* function graph compares on total time */
+static int function_stat_cmp(void *p1, void *p2)
+{
+ struct ftrace_profile *a = p1;
+ struct ftrace_profile *b = p2;
+
+ if (a->time < b->time)
+ return -1;
+ if (a->time > b->time)
+ return 1;
+ else
+ return 0;
+}
+#else
+/* not function graph compares against hits */
+static int function_stat_cmp(void *p1, void *p2)
+{
+ struct ftrace_profile *a = p1;
+ struct ftrace_profile *b = p2;
+
+ if (a->counter < b->counter)
+ return -1;
+ if (a->counter > b->counter)
+ return 1;
+ else
+ return 0;
+}
+#endif
+
+static int function_stat_headers(struct seq_file *m)
+{
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+ seq_printf(m, " Function "
+ "Hit Time Avg\n"
+ " -------- "
+ "--- ---- ---\n");
+#else
+ seq_printf(m, " Function Hit\n"
+ " -------- ---\n");
+#endif
+ return 0;
+}
+
+static int function_stat_show(struct seq_file *m, void *v)
+{
+ struct ftrace_profile *rec = v;
+ char str[KSYM_SYMBOL_LEN];
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+ static DEFINE_MUTEX(mutex);
+ static struct trace_seq s;
+ unsigned long long avg;
+#endif
+
+ kallsyms_lookup(rec->ip, NULL, NULL, NULL, str);
+ seq_printf(m, " %-30.30s %10lu", str, rec->counter);
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+ seq_printf(m, " ");
+ avg = rec->time;
+ do_div(avg, rec->counter);
+
+ mutex_lock(&mutex);
+ trace_seq_init(&s);
+ trace_print_graph_duration(rec->time, &s);
+ trace_seq_puts(&s, " ");
+ trace_print_graph_duration(avg, &s);
+ trace_print_seq(m, &s);
+ mutex_unlock(&mutex);
+#endif
+ seq_putc(m, '\n');
+
+ return 0;
+}
+
+static void ftrace_profile_reset(struct ftrace_profile_stat *stat)
+{
+ struct ftrace_profile_page *pg;
+
+ pg = stat->pages = stat->start;
+
+ while (pg) {
+ memset(pg->records, 0, PROFILE_RECORDS_SIZE);
+ pg->index = 0;
+ pg = pg->next;
+ }
+
+ memset(stat->hash, 0,
+ FTRACE_PROFILE_HASH_SIZE * sizeof(struct hlist_head));
+}
+
+int ftrace_profile_pages_init(struct ftrace_profile_stat *stat)
+{
+ struct ftrace_profile_page *pg;
+ int functions;
+ int pages;
+ int i;
+
+ /* If we already allocated, do nothing */
+ if (stat->pages)
+ return 0;
+
+ stat->pages = (void *)get_zeroed_page(GFP_KERNEL);
+ if (!stat->pages)
+ return -ENOMEM;
+
+#ifdef CONFIG_DYNAMIC_FTRACE
+ functions = ftrace_update_tot_cnt;
+#else
+ /*
+ * We do not know the number of functions that exist because
+ * dynamic tracing is what counts them. With past experience
+ * we have around 20K functions. That should be more than enough.
+ * It is highly unlikely we will execute every function in
+ * the kernel.
+ */
+ functions = 20000;
+#endif
+
+ pg = stat->start = stat->pages;
+
+ pages = DIV_ROUND_UP(functions, PROFILES_PER_PAGE);
+
+ for (i = 0; i < pages; i++) {
+ pg->next = (void *)get_zeroed_page(GFP_KERNEL);
+ if (!pg->next)
+ goto out_free;
+ pg = pg->next;
+ }
+
+ return 0;
+
+ out_free:
+ pg = stat->start;
+ while (pg) {
+ unsigned long tmp = (unsigned long)pg;
+
+ pg = pg->next;
+ free_page(tmp);
+ }
+
+ free_page((unsigned long)stat->pages);
+ stat->pages = NULL;
+ stat->start = NULL;
+
+ return -ENOMEM;
+}
+
+static int ftrace_profile_init_cpu(int cpu)
+{
+ struct ftrace_profile_stat *stat;
+ int size;
+
+ stat = &per_cpu(ftrace_profile_stats, cpu);
+
+ if (stat->hash) {
+ /* If the profile is already created, simply reset it */
+ ftrace_profile_reset(stat);
+ return 0;
+ }
+
+ /*
+ * We are profiling all functions, but usually only a few thousand
+ * functions are hit. We'll make a hash of 1024 items.
+ */
+ size = FTRACE_PROFILE_HASH_SIZE;
+
+ stat->hash = kzalloc(sizeof(struct hlist_head) * size, GFP_KERNEL);
+
+ if (!stat->hash)
+ return -ENOMEM;
+
+ if (!ftrace_profile_bits) {
+ size--;
+
+ for (; size; size >>= 1)
+ ftrace_profile_bits++;
+ }
+
+ /* Preallocate the function profiling pages */
+ if (ftrace_profile_pages_init(stat) < 0) {
+ kfree(stat->hash);
+ stat->hash = NULL;
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+static int ftrace_profile_init(void)
+{
+ int cpu;
+ int ret = 0;
+
+ for_each_online_cpu(cpu) {
+ ret = ftrace_profile_init_cpu(cpu);
+ if (ret)
+ break;
+ }
+
+ return ret;
+}
+
+/* interrupts must be disabled */
+static struct ftrace_profile *
+ftrace_find_profiled_func(struct ftrace_profile_stat *stat, unsigned long ip)
+{
+ struct ftrace_profile *rec;
+ struct hlist_head *hhd;
+ struct hlist_node *n;
+ unsigned long key;
+
+ key = hash_long(ip, ftrace_profile_bits);
+ hhd = &stat->hash[key];
+
+ if (hlist_empty(hhd))
+ return NULL;
+
+ hlist_for_each_entry_rcu(rec, n, hhd, node) {
+ if (rec->ip == ip)
+ return rec;
+ }
+
+ return NULL;
+}
+
+static void ftrace_add_profile(struct ftrace_profile_stat *stat,
+ struct ftrace_profile *rec)
+{
+ unsigned long key;
+
+ key = hash_long(rec->ip, ftrace_profile_bits);
+ hlist_add_head_rcu(&rec->node, &stat->hash[key]);
+}
+
+/*
+ * The memory is already allocated, this simply finds a new record to use.
+ */
+static struct ftrace_profile *
+ftrace_profile_alloc(struct ftrace_profile_stat *stat, unsigned long ip)
+{
+ struct ftrace_profile *rec = NULL;
+
+ /* prevent recursion (from NMIs) */
+ if (atomic_inc_return(&stat->disabled) != 1)
+ goto out;
+
+ /*
+ * Try to find the function again since an NMI
+ * could have added it
+ */
+ rec = ftrace_find_profiled_func(stat, ip);
+ if (rec)
+ goto out;
+
+ if (stat->pages->index == PROFILES_PER_PAGE) {
+ if (!stat->pages->next)
+ goto out;
+ stat->pages = stat->pages->next;
+ }
+
+ rec = &stat->pages->records[stat->pages->index++];
+ rec->ip = ip;
+ ftrace_add_profile(stat, rec);
+
+ out:
+ atomic_dec(&stat->disabled);
+
+ return rec;
+}
+
+static void
+function_profile_call(unsigned long ip, unsigned long parent_ip)
+{
+ struct ftrace_profile_stat *stat;
+ struct ftrace_profile *rec;
+ unsigned long flags;
+
+ if (!ftrace_profile_enabled)
+ return;
+
+ local_irq_save(flags);
+
+ stat = &__get_cpu_var(ftrace_profile_stats);
+ if (!stat->hash || !ftrace_profile_enabled)
+ goto out;
+
+ rec = ftrace_find_profiled_func(stat, ip);
+ if (!rec) {
+ rec = ftrace_profile_alloc(stat, ip);
+ if (!rec)
+ goto out;
+ }
+
+ rec->counter++;
+ out:
+ local_irq_restore(flags);
+}
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+static int profile_graph_entry(struct ftrace_graph_ent *trace)
+{
+ function_profile_call(trace->func, 0);
+ return 1;
+}
+
+static void profile_graph_return(struct ftrace_graph_ret *trace)
+{
+ struct ftrace_profile_stat *stat;
+ unsigned long long calltime;
+ struct ftrace_profile *rec;
+ unsigned long flags;
+
+ local_irq_save(flags);
+ stat = &__get_cpu_var(ftrace_profile_stats);
+ if (!stat->hash || !ftrace_profile_enabled)
+ goto out;
+
+ calltime = trace->rettime - trace->calltime;
+
+ if (!(trace_flags & TRACE_ITER_GRAPH_TIME)) {
+ int index;
+
+ index = trace->depth;
+
+ /* Append this call time to the parent time to subtract */
+ if (index)
+ current->ret_stack[index - 1].subtime += calltime;
+
+ if (current->ret_stack[index].subtime < calltime)
+ calltime -= current->ret_stack[index].subtime;
+ else
+ calltime = 0;
+ }
+
+ rec = ftrace_find_profiled_func(stat, trace->func);
+ if (rec)
+ rec->time += calltime;
+
+ out:
+ local_irq_restore(flags);
+}
+
+static int register_ftrace_profiler(void)
+{
+ return register_ftrace_graph(&profile_graph_return,
+ &profile_graph_entry);
+}
+
+static void unregister_ftrace_profiler(void)
+{
+ unregister_ftrace_graph();
+}
+#else
+static struct ftrace_ops ftrace_profile_ops __read_mostly =
+{
+ .func = function_profile_call,
+};
+
+static int register_ftrace_profiler(void)
+{
+ return register_ftrace_function(&ftrace_profile_ops);
+}
+
+static void unregister_ftrace_profiler(void)
+{
+ unregister_ftrace_function(&ftrace_profile_ops);
+}
+#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
+
+static ssize_t
+ftrace_profile_write(struct file *filp, const char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ unsigned long val;
+ char buf[64]; /* big enough to hold a number */
+ int ret;
+
+ if (cnt >= sizeof(buf))
+ return -EINVAL;
+
+ if (copy_from_user(&buf, ubuf, cnt))
+ return -EFAULT;
+
+ buf[cnt] = 0;
+
+ ret = strict_strtoul(buf, 10, &val);
+ if (ret < 0)
+ return ret;
+
+ val = !!val;
+
+ mutex_lock(&ftrace_profile_lock);
+ if (ftrace_profile_enabled ^ val) {
+ if (val) {
+ ret = ftrace_profile_init();
+ if (ret < 0) {
+ cnt = ret;
+ goto out;
+ }
+
+ ret = register_ftrace_profiler();
+ if (ret < 0) {
+ cnt = ret;
+ goto out;
+ }
+ ftrace_profile_enabled = 1;
+ } else {
+ ftrace_profile_enabled = 0;
+ /*
+ * unregister_ftrace_profiler calls stop_machine
+ * so this acts like an synchronize_sched.
+ */
+ unregister_ftrace_profiler();
+ }
+ }
+ out:
+ mutex_unlock(&ftrace_profile_lock);
+
+ *ppos += cnt;
+
+ return cnt;
+}
+
+static ssize_t
+ftrace_profile_read(struct file *filp, char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ char buf[64]; /* big enough to hold a number */
+ int r;
+
+ r = sprintf(buf, "%u\n", ftrace_profile_enabled);
+ return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
+}
+
+static const struct file_operations ftrace_profile_fops = {
+ .open = tracing_open_generic,
+ .read = ftrace_profile_read,
+ .write = ftrace_profile_write,
+};
+
+/* used to initialize the real stat files */
+static struct tracer_stat function_stats __initdata = {
+ .name = "functions",
+ .stat_start = function_stat_start,
+ .stat_next = function_stat_next,
+ .stat_cmp = function_stat_cmp,
+ .stat_headers = function_stat_headers,
+ .stat_show = function_stat_show
+};
+
+static __init void ftrace_profile_debugfs(struct dentry *d_tracer)
+{
+ struct ftrace_profile_stat *stat;
+ struct dentry *entry;
+ char *name;
+ int ret;
+ int cpu;
+
+ for_each_possible_cpu(cpu) {
+ stat = &per_cpu(ftrace_profile_stats, cpu);
+
+ /* allocate enough for function name + cpu number */
+ name = kmalloc(32, GFP_KERNEL);
+ if (!name) {
+ /*
+ * The files created are permanent, if something happens
+ * we still do not free memory.
+ */
+ WARN(1,
+ "Could not allocate stat file for cpu %d\n",
+ cpu);
+ return;
+ }
+ stat->stat = function_stats;
+ snprintf(name, 32, "function%d", cpu);
+ stat->stat.name = name;
+ ret = register_stat_tracer(&stat->stat);
+ if (ret) {
+ WARN(1,
+ "Could not register function stat for cpu %d\n",
+ cpu);
+ kfree(name);
+ return;
+ }
+ }
+
+ entry = debugfs_create_file("function_profile_enabled", 0644,
+ d_tracer, NULL, &ftrace_profile_fops);
+ if (!entry)
+ pr_warning("Could not create debugfs "
+ "'function_profile_enabled' entry\n");
+}
+
+#else /* CONFIG_FUNCTION_PROFILER */
+static __init void ftrace_profile_debugfs(struct dentry *d_tracer)
+{
+}
+#endif /* CONFIG_FUNCTION_PROFILER */
+
static struct pid * const ftrace_swapper_pid = &init_struct_pid;
#ifdef CONFIG_DYNAMIC_FTRACE
struct rcu_head rcu;
};
-
enum {
FTRACE_ENABLE_CALLS = (1 << 0),
FTRACE_DISABLE_CALLS = (1 << 1),
static void ftrace_free_rec(struct dyn_ftrace *rec)
{
- rec->ip = (unsigned long)ftrace_free_records;
+ rec->freelist = ftrace_free_records;
ftrace_free_records = rec;
rec->flags |= FTRACE_FL_FREE;
}
-void ftrace_release(void *start, unsigned long size)
-{
- struct dyn_ftrace *rec;
- struct ftrace_page *pg;
- unsigned long s = (unsigned long)start;
- unsigned long e = s + size;
-
- if (ftrace_disabled || !start)
- return;
-
- mutex_lock(&ftrace_lock);
- do_for_each_ftrace_rec(pg, rec) {
- if ((rec->ip >= s) && (rec->ip < e) &&
- !(rec->flags & FTRACE_FL_FREE))
- ftrace_free_rec(rec);
- } while_for_each_ftrace_rec();
- mutex_unlock(&ftrace_lock);
-}
-
static struct dyn_ftrace *ftrace_alloc_dyn_node(unsigned long ip)
{
struct dyn_ftrace *rec;
return NULL;
}
- ftrace_free_records = (void *)rec->ip;
+ ftrace_free_records = rec->freelist;
memset(rec, 0, sizeof(*rec));
return rec;
}
return NULL;
rec->ip = ip;
- rec->flags = (unsigned long)ftrace_new_addrs;
+ rec->newlist = ftrace_new_addrs;
ftrace_new_addrs = rec;
return rec;
__ftrace_replace_code(struct dyn_ftrace *rec, int enable)
{
unsigned long ftrace_addr;
- unsigned long ip, fl;
+ unsigned long flag = 0UL;
ftrace_addr = (unsigned long)FTRACE_ADDR;
- ip = rec->ip;
-
/*
- * If this record is not to be traced and
- * it is not enabled then do nothing.
+ * If this record is not to be traced or we want to disable it,
+ * then disable it.
*
- * If this record is not to be traced and
- * it is enabled then disable it.
+ * If we want to enable it and filtering is off, then enable it.
*
+ * If we want to enable it and filtering is on, enable it only if
+ * it's filtered
*/
- if (rec->flags & FTRACE_FL_NOTRACE) {
- if (rec->flags & FTRACE_FL_ENABLED)
- rec->flags &= ~FTRACE_FL_ENABLED;
- else
- return 0;
-
- } else if (ftrace_filtered && enable) {
- /*
- * Filtering is on:
- */
-
- fl = rec->flags & (FTRACE_FL_FILTER | FTRACE_FL_ENABLED);
-
- /* Record is filtered and enabled, do nothing */
- if (fl == (FTRACE_FL_FILTER | FTRACE_FL_ENABLED))
- return 0;
-
- /* Record is not filtered or enabled, do nothing */
- if (!fl)
- return 0;
-
- /* Record is not filtered but enabled, disable it */
- if (fl == FTRACE_FL_ENABLED)
- rec->flags &= ~FTRACE_FL_ENABLED;
- else
- /* Otherwise record is filtered but not enabled, enable it */
- rec->flags |= FTRACE_FL_ENABLED;
- } else {
- /* Disable or not filtered */
-
- if (enable) {
- /* if record is enabled, do nothing */
- if (rec->flags & FTRACE_FL_ENABLED)
- return 0;
-
- rec->flags |= FTRACE_FL_ENABLED;
-
- } else {
+ if (enable && !(rec->flags & FTRACE_FL_NOTRACE)) {
+ if (!ftrace_filtered || (rec->flags & FTRACE_FL_FILTER))
+ flag = FTRACE_FL_ENABLED;
+ }
- /* if record is not enabled, do nothing */
- if (!(rec->flags & FTRACE_FL_ENABLED))
- return 0;
+ /* If the state of this record hasn't changed, then do nothing */
+ if ((rec->flags & FTRACE_FL_ENABLED) == flag)
+ return 0;
- rec->flags &= ~FTRACE_FL_ENABLED;
- }
+ if (flag) {
+ rec->flags |= FTRACE_FL_ENABLED;
+ return ftrace_make_call(rec, ftrace_addr);
}
- if (rec->flags & FTRACE_FL_ENABLED)
- return ftrace_make_call(rec, ftrace_addr);
- else
- return ftrace_make_nop(NULL, rec, ftrace_addr);
+ rec->flags &= ~FTRACE_FL_ENABLED;
+ return ftrace_make_nop(NULL, rec, ftrace_addr);
}
static void ftrace_replace_code(int enable)
*/
if (rec->flags & FTRACE_FL_FREE ||
rec->flags & FTRACE_FL_FAILED ||
- rec->flags & FTRACE_FL_CONVERTED)
+ !(rec->flags & FTRACE_FL_CONVERTED))
continue;
/* ignore updates to this record's mcount site */
failed = __ftrace_replace_code(rec, enable);
if (failed) {
rec->flags |= FTRACE_FL_FAILED;
- if ((system_state == SYSTEM_BOOTING) ||
- !core_kernel_text(rec->ip)) {
- ftrace_free_rec(rec);
- } else {
- ftrace_bug(failed, rec->ip);
- /* Stop processing */
- return;
- }
+ ftrace_bug(failed, rec->ip);
+ /* Stop processing */
+ return;
}
} while_for_each_ftrace_rec();
}
return;
ftrace_start_up--;
+ /*
+ * Just warn in case of unbalance, no need to kill ftrace, it's not
+ * critical but the ftrace_call callers may be never nopped again after
+ * further ftrace uses.
+ */
+ WARN_ON_ONCE(ftrace_start_up < 0);
+
if (!ftrace_start_up)
command |= FTRACE_DISABLE_CALLS;
return -1;
p = ftrace_new_addrs;
- ftrace_new_addrs = (struct dyn_ftrace *)p->flags;
+ ftrace_new_addrs = p->newlist;
p->flags = 0L;
- /* convert record (i.e, patch mcount-call with NOP) */
- if (ftrace_code_disable(mod, p)) {
- p->flags |= FTRACE_FL_CONVERTED;
- ftrace_update_cnt++;
- } else
+ /*
+ * Do the initial record convertion from mcount jump
+ * to the NOP instructions.
+ */
+ if (!ftrace_code_disable(mod, p)) {
ftrace_free_rec(p);
+ continue;
+ }
+
+ p->flags |= FTRACE_FL_CONVERTED;
+ ftrace_update_cnt++;
+
+ /*
+ * If the tracing is enabled, go ahead and enable the record.
+ *
+ * The reason not to enable the record immediatelly is the
+ * inherent check of ftrace_make_nop/ftrace_make_call for
+ * correct previous instructions. Making first the NOP
+ * conversion puts the module to the correct state, thus
+ * passing the ftrace_make_call check.
+ */
+ if (ftrace_start_up) {
+ int failed = __ftrace_replace_code(p, 1);
+ if (failed) {
+ ftrace_bug(failed, p->ip);
+ ftrace_free_rec(p);
+ }
+ }
}
stop = ftrace_now(raw_smp_processor_id());
enum {
FTRACE_ITER_FILTER = (1 << 0),
- FTRACE_ITER_CONT = (1 << 1),
- FTRACE_ITER_NOTRACE = (1 << 2),
- FTRACE_ITER_FAILURES = (1 << 3),
- FTRACE_ITER_PRINTALL = (1 << 4),
- FTRACE_ITER_HASH = (1 << 5),
+ FTRACE_ITER_NOTRACE = (1 << 1),
+ FTRACE_ITER_FAILURES = (1 << 2),
+ FTRACE_ITER_PRINTALL = (1 << 3),
+ FTRACE_ITER_HASH = (1 << 4),
};
#define FTRACE_BUFF_MAX (KSYM_SYMBOL_LEN+4) /* room for wildcards */
int hidx;
int idx;
unsigned flags;
- unsigned char buffer[FTRACE_BUFF_MAX+1];
- unsigned buffer_idx;
- unsigned filtered;
+ struct trace_parser parser;
};
static void *
{
struct ftrace_iterator *iter = m->private;
void *p = NULL;
+ loff_t l;
+
+ if (!(iter->flags & FTRACE_ITER_HASH))
+ *pos = 0;
iter->flags |= FTRACE_ITER_HASH;
- return t_hash_next(m, p, pos);
+ iter->hidx = 0;
+ for (l = 0; l <= *pos; ) {
+ p = t_hash_next(m, p, &l);
+ if (!p)
+ break;
+ }
+ return p;
}
static int t_hash_show(struct seq_file *m, void *v)
{
struct ftrace_func_probe *rec;
struct hlist_node *hnd = v;
- char str[KSYM_SYMBOL_LEN];
rec = hlist_entry(hnd, struct ftrace_func_probe, node);
if (rec->ops->print)
return rec->ops->print(m, rec->ip, rec->ops, rec->data);
- kallsyms_lookup(rec->ip, NULL, NULL, NULL, str);
- seq_printf(m, "%s:", str);
-
- kallsyms_lookup((unsigned long)rec->ops->func, NULL, NULL, NULL, str);
- seq_printf(m, "%s", str);
+ seq_printf(m, "%ps:%ps", (void *)rec->ip, (void *)rec->ops->func);
if (rec->data)
seq_printf(m, ":%p", rec->data);
iter->pg = iter->pg->next;
iter->idx = 0;
goto retry;
- } else {
- iter->idx = -1;
}
} else {
rec = &iter->pg->records[iter->idx++];
{
struct ftrace_iterator *iter = m->private;
void *p = NULL;
+ loff_t l;
mutex_lock(&ftrace_lock);
/*
if (*pos > 0)
return t_hash_start(m, pos);
iter->flags |= FTRACE_ITER_PRINTALL;
- (*pos)++;
return iter;
}
if (iter->flags & FTRACE_ITER_HASH)
return t_hash_start(m, pos);
- if (*pos > 0) {
- if (iter->idx < 0)
- return p;
- (*pos)--;
- iter->idx--;
+ iter->pg = ftrace_pages_start;
+ iter->idx = 0;
+ for (l = 0; l <= *pos; ) {
+ p = t_next(m, p, &l);
+ if (!p)
+ break;
}
- p = t_next(m, p, pos);
-
- if (!p)
+ if (!p && iter->flags & FTRACE_ITER_FILTER)
return t_hash_start(m, pos);
return p;
{
struct ftrace_iterator *iter = m->private;
struct dyn_ftrace *rec = v;
- char str[KSYM_SYMBOL_LEN];
if (iter->flags & FTRACE_ITER_HASH)
return t_hash_show(m, v);
if (!rec)
return 0;
- kallsyms_lookup(rec->ip, NULL, NULL, NULL, str);
-
- seq_printf(m, "%s\n", str);
+ seq_printf(m, "%ps\n", (void *)rec->ip);
return 0;
}
-static struct seq_operations show_ftrace_seq_ops = {
+static const struct seq_operations show_ftrace_seq_ops = {
.start = t_start,
.next = t_next,
.stop = t_stop,
return ret;
}
-int ftrace_avail_release(struct inode *inode, struct file *file)
-{
- struct seq_file *m = (struct seq_file *)file->private_data;
- struct ftrace_iterator *iter = m->private;
-
- seq_release(inode, file);
- kfree(iter);
-
- return 0;
-}
-
static int
ftrace_failures_open(struct inode *inode, struct file *file)
{
if (!iter)
return -ENOMEM;
+ if (trace_parser_get_init(&iter->parser, FTRACE_BUFF_MAX)) {
+ kfree(iter);
+ return -ENOMEM;
+ }
+
mutex_lock(&ftrace_regex_lock);
if ((file->f_mode & FMODE_WRITE) &&
- !(file->f_flags & O_APPEND))
+ (file->f_flags & O_TRUNC))
ftrace_filter_reset(enable);
if (file->f_mode & FMODE_READ) {
if (!ret) {
struct seq_file *m = file->private_data;
m->private = iter;
- } else
+ } else {
+ trace_parser_put(&iter->parser);
kfree(iter);
+ }
} else
file->private_data = iter;
mutex_unlock(&ftrace_regex_lock);
return ret;
}
-enum {
- MATCH_FULL,
- MATCH_FRONT_ONLY,
- MATCH_MIDDLE_ONLY,
- MATCH_END_ONLY,
-};
-
-/*
- * (static function - no need for kernel doc)
- *
- * Pass in a buffer containing a glob and this function will
- * set search to point to the search part of the buffer and
- * return the type of search it is (see enum above).
- * This does modify buff.
- *
- * Returns enum type.
- * search returns the pointer to use for comparison.
- * not returns 1 if buff started with a '!'
- * 0 otherwise.
- */
-static int
-ftrace_setup_glob(char *buff, int len, char **search, int *not)
-{
- int type = MATCH_FULL;
- int i;
-
- if (buff[0] == '!') {
- *not = 1;
- buff++;
- len--;
- } else
- *not = 0;
-
- *search = buff;
-
- for (i = 0; i < len; i++) {
- if (buff[i] == '*') {
- if (!i) {
- *search = buff + 1;
- type = MATCH_END_ONLY;
- } else {
- if (type == MATCH_END_ONLY)
- type = MATCH_MIDDLE_ONLY;
- else
- type = MATCH_FRONT_ONLY;
- buff[i] = 0;
- break;
- }
- }
- }
-
- return type;
-}
-
static int ftrace_match(char *str, char *regex, int len, int type)
{
int matched = 0;
int not;
flag = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE;
- type = ftrace_setup_glob(buff, len, &search, ¬);
+ type = filter_parse_regex(buff, len, &search, ¬);
search_len = strlen(search);
}
if (strlen(buff)) {
- type = ftrace_setup_glob(buff, strlen(buff), &search, ¬);
+ type = filter_parse_regex(buff, strlen(buff), &search, ¬);
search_len = strlen(search);
}
static struct ftrace_ops trace_probe_ops __read_mostly =
{
- .func = function_trace_probe_call,
+ .func = function_trace_probe_call,
};
static int ftrace_probe_registered;
int count = 0;
char *search;
- type = ftrace_setup_glob(glob, strlen(glob), &search, ¬);
+ type = filter_parse_regex(glob, strlen(glob), &search, ¬);
len = strlen(search);
/* we do not support '!' for function probes */
int i, len = 0;
char *search;
- if (glob && (strcmp(glob, "*") || !strlen(glob)))
+ if (glob && (strcmp(glob, "*") == 0 || !strlen(glob)))
glob = NULL;
- else {
+ else if (glob) {
int not;
- type = ftrace_setup_glob(glob, strlen(glob), &search, ¬);
+ type = filter_parse_regex(glob, strlen(glob), &search, ¬);
len = strlen(search);
/* we do not support '!' for function probes */
size_t cnt, loff_t *ppos, int enable)
{
struct ftrace_iterator *iter;
- char ch;
- size_t read = 0;
- ssize_t ret;
+ struct trace_parser *parser;
+ ssize_t ret, read;
- if (!cnt || cnt < 0)
+ if (!cnt)
return 0;
mutex_lock(&ftrace_regex_lock);
} else
iter = file->private_data;
- if (!*ppos) {
- iter->flags &= ~FTRACE_ITER_CONT;
- iter->buffer_idx = 0;
- }
-
- ret = get_user(ch, ubuf++);
- if (ret)
- goto out;
- read++;
- cnt--;
-
- if (!(iter->flags & ~FTRACE_ITER_CONT)) {
- /* skip white space */
- while (cnt && isspace(ch)) {
- ret = get_user(ch, ubuf++);
- if (ret)
- goto out;
- read++;
- cnt--;
- }
-
- if (isspace(ch)) {
- file->f_pos += read;
- ret = read;
- goto out;
- }
-
- iter->buffer_idx = 0;
- }
+ parser = &iter->parser;
+ read = trace_get_user(parser, ubuf, cnt, ppos);
- while (cnt && !isspace(ch)) {
- if (iter->buffer_idx < FTRACE_BUFF_MAX)
- iter->buffer[iter->buffer_idx++] = ch;
- else {
- ret = -EINVAL;
- goto out;
- }
- ret = get_user(ch, ubuf++);
+ if (read >= 0 && trace_parser_loaded(parser) &&
+ !trace_parser_cont(parser)) {
+ ret = ftrace_process_regex(parser->buffer,
+ parser->idx, enable);
if (ret)
goto out;
- read++;
- cnt--;
- }
- if (isspace(ch)) {
- iter->filtered++;
- iter->buffer[iter->buffer_idx] = 0;
- ret = ftrace_process_regex(iter->buffer,
- iter->buffer_idx, enable);
- if (ret)
- goto out;
- iter->buffer_idx = 0;
- } else
- iter->flags |= FTRACE_ITER_CONT;
-
-
- file->f_pos += read;
+ trace_parser_clear(parser);
+ }
ret = read;
- out:
- mutex_unlock(&ftrace_regex_lock);
+ mutex_unlock(&ftrace_regex_lock);
+out:
return ret;
}
ftrace_set_regex(buf, len, reset, 0);
}
+/*
+ * command line interface to allow users to set filters on boot up.
+ */
+#define FTRACE_FILTER_SIZE COMMAND_LINE_SIZE
+static char ftrace_notrace_buf[FTRACE_FILTER_SIZE] __initdata;
+static char ftrace_filter_buf[FTRACE_FILTER_SIZE] __initdata;
+static char ftrace_graph_buf[FTRACE_FILTER_SIZE] __initdata;
+
+static int __init set_ftrace_notrace(char *str)
+{
+ strncpy(ftrace_notrace_buf, str, FTRACE_FILTER_SIZE);
+ return 1;
+}
+__setup("ftrace_notrace=", set_ftrace_notrace);
+
+static int __init set_ftrace_filter(char *str)
+{
+ strncpy(ftrace_filter_buf, str, FTRACE_FILTER_SIZE);
+ return 1;
+}
+__setup("ftrace_filter=", set_ftrace_filter);
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+static int __init set_graph_function(char *str)
+{
+ strlcpy(ftrace_graph_buf, str, FTRACE_FILTER_SIZE);
+ return 1;
+}
+__setup("ftrace_graph_filter=", set_graph_function);
+
+static void __init set_ftrace_early_graph(char *buf)
+{
+ int ret;
+ char *func;
+
+ while (buf) {
+ func = strsep(&buf, ",");
+ /* we allow only one expression at a time */
+ ret = ftrace_set_func(ftrace_graph_funcs, &ftrace_graph_count,
+ func);
+ if (ret)
+ printk(KERN_DEBUG "ftrace: function %s not "
+ "traceable\n", func);
+ }
+}
+#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
+
+static void __init set_ftrace_early_filter(char *buf, int enable)
+{
+ char *func;
+
+ while (buf) {
+ func = strsep(&buf, ",");
+ ftrace_set_regex(func, strlen(func), 0, enable);
+ }
+}
+
+static void __init set_ftrace_early_filters(void)
+{
+ if (ftrace_filter_buf[0])
+ set_ftrace_early_filter(ftrace_filter_buf, 1);
+ if (ftrace_notrace_buf[0])
+ set_ftrace_early_filter(ftrace_notrace_buf, 0);
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+ if (ftrace_graph_buf[0])
+ set_ftrace_early_graph(ftrace_graph_buf);
+#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
+}
+
static int
ftrace_regex_release(struct inode *inode, struct file *file, int enable)
{
struct seq_file *m = (struct seq_file *)file->private_data;
struct ftrace_iterator *iter;
+ struct trace_parser *parser;
mutex_lock(&ftrace_regex_lock);
if (file->f_mode & FMODE_READ) {
} else
iter = file->private_data;
- if (iter->buffer_idx) {
- iter->filtered++;
- iter->buffer[iter->buffer_idx] = 0;
- ftrace_match_records(iter->buffer, iter->buffer_idx, enable);
+ parser = &iter->parser;
+ if (trace_parser_loaded(parser)) {
+ parser->buffer[parser->idx] = 0;
+ ftrace_match_records(parser->buffer, parser->idx, enable);
}
mutex_lock(&ftrace_lock);
ftrace_run_update_code(FTRACE_ENABLE_CALLS);
mutex_unlock(&ftrace_lock);
+ trace_parser_put(parser);
kfree(iter);
+
mutex_unlock(&ftrace_regex_lock);
return 0;
}
.open = ftrace_avail_open,
.read = seq_read,
.llseek = seq_lseek,
- .release = ftrace_avail_release,
+ .release = seq_release_private,
};
static const struct file_operations ftrace_failures_fops = {
.open = ftrace_failures_open,
.read = seq_read,
.llseek = seq_lseek,
- .release = ftrace_avail_release,
+ .release = seq_release_private,
};
static const struct file_operations ftrace_filter_fops = {
unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS] __read_mostly;
static void *
-g_next(struct seq_file *m, void *v, loff_t *pos)
+__g_next(struct seq_file *m, loff_t *pos)
{
- unsigned long *array = m->private;
- int index = *pos;
-
- (*pos)++;
-
- if (index >= ftrace_graph_count)
+ if (*pos >= ftrace_graph_count)
return NULL;
+ return &ftrace_graph_funcs[*pos];
+}
- return &array[index];
+static void *
+g_next(struct seq_file *m, void *v, loff_t *pos)
+{
+ (*pos)++;
+ return __g_next(m, pos);
}
static void *g_start(struct seq_file *m, loff_t *pos)
{
- void *p = NULL;
-
mutex_lock(&graph_lock);
/* Nothing, tell g_show to print all functions are enabled */
if (!ftrace_graph_count && !*pos)
return (void *)1;
- p = g_next(m, p, pos);
-
- return p;
+ return __g_next(m, pos);
}
static void g_stop(struct seq_file *m, void *p)
static int g_show(struct seq_file *m, void *v)
{
unsigned long *ptr = v;
- char str[KSYM_SYMBOL_LEN];
if (!ptr)
return 0;
return 0;
}
- kallsyms_lookup(*ptr, NULL, NULL, NULL, str);
-
- seq_printf(m, "%s\n", str);
+ seq_printf(m, "%ps\n", (void *)*ptr);
return 0;
}
-static struct seq_operations ftrace_graph_seq_ops = {
+static const struct seq_operations ftrace_graph_seq_ops = {
.start = g_start,
.next = g_next,
.stop = g_stop,
mutex_lock(&graph_lock);
if ((file->f_mode & FMODE_WRITE) &&
- !(file->f_flags & O_APPEND)) {
+ (file->f_flags & O_TRUNC)) {
ftrace_graph_count = 0;
memset(ftrace_graph_funcs, 0, sizeof(ftrace_graph_funcs));
}
+ mutex_unlock(&graph_lock);
- if (file->f_mode & FMODE_READ) {
+ if (file->f_mode & FMODE_READ)
ret = seq_open(file, &ftrace_graph_seq_ops);
- if (!ret) {
- struct seq_file *m = file->private_data;
- m->private = ftrace_graph_funcs;
- }
- } else
- file->private_data = ftrace_graph_funcs;
- mutex_unlock(&graph_lock);
return ret;
}
static int
+ftrace_graph_release(struct inode *inode, struct file *file)
+{
+ if (file->f_mode & FMODE_READ)
+ seq_release(inode, file);
+ return 0;
+}
+
+static int
ftrace_set_func(unsigned long *array, int *idx, char *buffer)
{
struct dyn_ftrace *rec;
return -ENODEV;
/* decode regex */
- type = ftrace_setup_glob(buffer, strlen(buffer), &search, ¬);
+ type = filter_parse_regex(buffer, strlen(buffer), &search, ¬);
if (not)
return -EINVAL;
ftrace_graph_write(struct file *file, const char __user *ubuf,
size_t cnt, loff_t *ppos)
{
- unsigned char buffer[FTRACE_BUFF_MAX+1];
- unsigned long *array;
- size_t read = 0;
- ssize_t ret;
- int index = 0;
- char ch;
+ struct trace_parser parser;
+ ssize_t read, ret;
if (!cnt || cnt < 0)
return 0;
if (ftrace_graph_count >= FTRACE_GRAPH_MAX_FUNCS) {
ret = -EBUSY;
- goto out;
+ goto out_unlock;
}
- if (file->f_mode & FMODE_READ) {
- struct seq_file *m = file->private_data;
- array = m->private;
- } else
- array = file->private_data;
-
- ret = get_user(ch, ubuf++);
- if (ret)
- goto out;
- read++;
- cnt--;
-
- /* skip white space */
- while (cnt && isspace(ch)) {
- ret = get_user(ch, ubuf++);
- if (ret)
- goto out;
- read++;
- cnt--;
+ if (trace_parser_get_init(&parser, FTRACE_BUFF_MAX)) {
+ ret = -ENOMEM;
+ goto out_unlock;
}
- if (isspace(ch)) {
- *ppos += read;
- ret = read;
- goto out;
- }
+ read = trace_get_user(&parser, ubuf, cnt, ppos);
- while (cnt && !isspace(ch)) {
- if (index < FTRACE_BUFF_MAX)
- buffer[index++] = ch;
- else {
- ret = -EINVAL;
- goto out;
- }
- ret = get_user(ch, ubuf++);
+ if (read >= 0 && trace_parser_loaded((&parser))) {
+ parser.buffer[parser.idx] = 0;
+
+ /* we allow only one expression at a time */
+ ret = ftrace_set_func(ftrace_graph_funcs, &ftrace_graph_count,
+ parser.buffer);
if (ret)
- goto out;
- read++;
- cnt--;
+ goto out_free;
}
- buffer[index] = 0;
-
- /* we allow only one expression at a time */
- ret = ftrace_set_func(array, &ftrace_graph_count, buffer);
- if (ret)
- goto out;
-
- file->f_pos += read;
ret = read;
- out:
+
+out_free:
+ trace_parser_put(&parser);
+out_unlock:
mutex_unlock(&graph_lock);
return ret;
}
static const struct file_operations ftrace_graph_fops = {
- .open = ftrace_graph_open,
- .read = seq_read,
- .write = ftrace_graph_write,
+ .open = ftrace_graph_open,
+ .read = seq_read,
+ .write = ftrace_graph_write,
+ .release = ftrace_graph_release,
};
#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
static __init int ftrace_init_dyn_debugfs(struct dentry *d_tracer)
{
- struct dentry *entry;
- entry = debugfs_create_file("available_filter_functions", 0444,
- d_tracer, NULL, &ftrace_avail_fops);
- if (!entry)
- pr_warning("Could not create debugfs "
- "'available_filter_functions' entry\n");
+ trace_create_file("available_filter_functions", 0444,
+ d_tracer, NULL, &ftrace_avail_fops);
- entry = debugfs_create_file("failures", 0444,
- d_tracer, NULL, &ftrace_failures_fops);
- if (!entry)
- pr_warning("Could not create debugfs 'failures' entry\n");
+ trace_create_file("failures", 0444,
+ d_tracer, NULL, &ftrace_failures_fops);
- entry = debugfs_create_file("set_ftrace_filter", 0644, d_tracer,
- NULL, &ftrace_filter_fops);
- if (!entry)
- pr_warning("Could not create debugfs "
- "'set_ftrace_filter' entry\n");
+ trace_create_file("set_ftrace_filter", 0644, d_tracer,
+ NULL, &ftrace_filter_fops);
- entry = debugfs_create_file("set_ftrace_notrace", 0644, d_tracer,
+ trace_create_file("set_ftrace_notrace", 0644, d_tracer,
NULL, &ftrace_notrace_fops);
- if (!entry)
- pr_warning("Could not create debugfs "
- "'set_ftrace_notrace' entry\n");
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
- entry = debugfs_create_file("set_graph_function", 0444, d_tracer,
+ trace_create_file("set_graph_function", 0444, d_tracer,
NULL,
&ftrace_graph_fops);
- if (!entry)
- pr_warning("Could not create debugfs "
- "'set_graph_function' entry\n");
#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
return 0;
}
-static int ftrace_convert_nops(struct module *mod,
+static int ftrace_process_locs(struct module *mod,
unsigned long *start,
unsigned long *end)
{
return 0;
}
-void ftrace_init_module(struct module *mod,
- unsigned long *start, unsigned long *end)
+#ifdef CONFIG_MODULES
+void ftrace_release_mod(struct module *mod)
+{
+ struct dyn_ftrace *rec;
+ struct ftrace_page *pg;
+
+ if (ftrace_disabled)
+ return;
+
+ mutex_lock(&ftrace_lock);
+ do_for_each_ftrace_rec(pg, rec) {
+ if (within_module_core(rec->ip, mod)) {
+ /*
+ * rec->ip is changed in ftrace_free_rec()
+ * It should not between s and e if record was freed.
+ */
+ FTRACE_WARN_ON(rec->flags & FTRACE_FL_FREE);
+ ftrace_free_rec(rec);
+ }
+ } while_for_each_ftrace_rec();
+ mutex_unlock(&ftrace_lock);
+}
+
+static void ftrace_init_module(struct module *mod,
+ unsigned long *start, unsigned long *end)
{
if (ftrace_disabled || start == end)
return;
- ftrace_convert_nops(mod, start, end);
+ ftrace_process_locs(mod, start, end);
+}
+
+static int ftrace_module_notify(struct notifier_block *self,
+ unsigned long val, void *data)
+{
+ struct module *mod = data;
+
+ switch (val) {
+ case MODULE_STATE_COMING:
+ ftrace_init_module(mod, mod->ftrace_callsites,
+ mod->ftrace_callsites +
+ mod->num_ftrace_callsites);
+ break;
+ case MODULE_STATE_GOING:
+ ftrace_release_mod(mod);
+ break;
+ }
+
+ return 0;
+}
+#else
+static int ftrace_module_notify(struct notifier_block *self,
+ unsigned long val, void *data)
+{
+ return 0;
}
+#endif /* CONFIG_MODULES */
+
+struct notifier_block ftrace_module_nb = {
+ .notifier_call = ftrace_module_notify,
+ .priority = 0,
+};
extern unsigned long __start_mcount_loc[];
extern unsigned long __stop_mcount_loc[];
last_ftrace_enabled = ftrace_enabled = 1;
- ret = ftrace_convert_nops(NULL,
+ ret = ftrace_process_locs(NULL,
__start_mcount_loc,
__stop_mcount_loc);
+ ret = register_module_notifier(&ftrace_module_nb);
+ if (ret)
+ pr_warning("Failed to register trace ftrace module notifier\n");
+
+ set_ftrace_early_filters();
+
return;
failed:
ftrace_disabled = 1;
# define ftrace_shutdown_sysctl() do { } while (0)
#endif /* CONFIG_DYNAMIC_FTRACE */
-static ssize_t
-ftrace_pid_read(struct file *file, char __user *ubuf,
- size_t cnt, loff_t *ppos)
-{
- char buf[64];
- int r;
-
- if (ftrace_pid_trace == ftrace_swapper_pid)
- r = sprintf(buf, "swapper tasks\n");
- else if (ftrace_pid_trace)
- r = sprintf(buf, "%u\n", pid_nr(ftrace_pid_trace));
- else
- r = sprintf(buf, "no pid\n");
-
- return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
-}
-
static void clear_ftrace_swapper(void)
{
struct task_struct *p;
rcu_read_unlock();
}
-static void clear_ftrace_pid_task(struct pid **pid)
+static void clear_ftrace_pid_task(struct pid *pid)
{
- if (*pid == ftrace_swapper_pid)
+ if (pid == ftrace_swapper_pid)
clear_ftrace_swapper();
else
- clear_ftrace_pid(*pid);
-
- *pid = NULL;
+ clear_ftrace_pid(pid);
}
static void set_ftrace_pid_task(struct pid *pid)
set_ftrace_pid(pid);
}
+static int ftrace_pid_add(int p)
+{
+ struct pid *pid;
+ struct ftrace_pid *fpid;
+ int ret = -EINVAL;
+
+ mutex_lock(&ftrace_lock);
+
+ if (!p)
+ pid = ftrace_swapper_pid;
+ else
+ pid = find_get_pid(p);
+
+ if (!pid)
+ goto out;
+
+ ret = 0;
+
+ list_for_each_entry(fpid, &ftrace_pids, list)
+ if (fpid->pid == pid)
+ goto out_put;
+
+ ret = -ENOMEM;
+
+ fpid = kmalloc(sizeof(*fpid), GFP_KERNEL);
+ if (!fpid)
+ goto out_put;
+
+ list_add(&fpid->list, &ftrace_pids);
+ fpid->pid = pid;
+
+ set_ftrace_pid_task(pid);
+
+ ftrace_update_pid_func();
+ ftrace_startup_enable(0);
+
+ mutex_unlock(&ftrace_lock);
+ return 0;
+
+out_put:
+ if (pid != ftrace_swapper_pid)
+ put_pid(pid);
+
+out:
+ mutex_unlock(&ftrace_lock);
+ return ret;
+}
+
+static void ftrace_pid_reset(void)
+{
+ struct ftrace_pid *fpid, *safe;
+
+ mutex_lock(&ftrace_lock);
+ list_for_each_entry_safe(fpid, safe, &ftrace_pids, list) {
+ struct pid *pid = fpid->pid;
+
+ clear_ftrace_pid_task(pid);
+
+ list_del(&fpid->list);
+ kfree(fpid);
+ }
+
+ ftrace_update_pid_func();
+ ftrace_startup_enable(0);
+
+ mutex_unlock(&ftrace_lock);
+}
+
+static void *fpid_start(struct seq_file *m, loff_t *pos)
+{
+ mutex_lock(&ftrace_lock);
+
+ if (list_empty(&ftrace_pids) && (!*pos))
+ return (void *) 1;
+
+ return seq_list_start(&ftrace_pids, *pos);
+}
+
+static void *fpid_next(struct seq_file *m, void *v, loff_t *pos)
+{
+ if (v == (void *)1)
+ return NULL;
+
+ return seq_list_next(v, &ftrace_pids, pos);
+}
+
+static void fpid_stop(struct seq_file *m, void *p)
+{
+ mutex_unlock(&ftrace_lock);
+}
+
+static int fpid_show(struct seq_file *m, void *v)
+{
+ const struct ftrace_pid *fpid = list_entry(v, struct ftrace_pid, list);
+
+ if (v == (void *)1) {
+ seq_printf(m, "no pid\n");
+ return 0;
+ }
+
+ if (fpid->pid == ftrace_swapper_pid)
+ seq_printf(m, "swapper tasks\n");
+ else
+ seq_printf(m, "%u\n", pid_vnr(fpid->pid));
+
+ return 0;
+}
+
+static const struct seq_operations ftrace_pid_sops = {
+ .start = fpid_start,
+ .next = fpid_next,
+ .stop = fpid_stop,
+ .show = fpid_show,
+};
+
+static int
+ftrace_pid_open(struct inode *inode, struct file *file)
+{
+ int ret = 0;
+
+ if ((file->f_mode & FMODE_WRITE) &&
+ (file->f_flags & O_TRUNC))
+ ftrace_pid_reset();
+
+ if (file->f_mode & FMODE_READ)
+ ret = seq_open(file, &ftrace_pid_sops);
+
+ return ret;
+}
+
static ssize_t
ftrace_pid_write(struct file *filp, const char __user *ubuf,
size_t cnt, loff_t *ppos)
{
- struct pid *pid;
char buf[64];
long val;
int ret;
buf[cnt] = 0;
+ /*
+ * Allow "echo > set_ftrace_pid" or "echo -n '' > set_ftrace_pid"
+ * to clean the filter quietly.
+ */
+ strstrip(buf);
+ if (strlen(buf) == 0)
+ return 1;
+
ret = strict_strtol(buf, 10, &val);
if (ret < 0)
return ret;
- mutex_lock(&ftrace_lock);
- if (val < 0) {
- /* disable pid tracing */
- if (!ftrace_pid_trace)
- goto out;
-
- clear_ftrace_pid_task(&ftrace_pid_trace);
-
- } else {
- /* swapper task is special */
- if (!val) {
- pid = ftrace_swapper_pid;
- if (pid == ftrace_pid_trace)
- goto out;
- } else {
- pid = find_get_pid(val);
-
- if (pid == ftrace_pid_trace) {
- put_pid(pid);
- goto out;
- }
- }
-
- if (ftrace_pid_trace)
- clear_ftrace_pid_task(&ftrace_pid_trace);
-
- if (!pid)
- goto out;
-
- ftrace_pid_trace = pid;
+ ret = ftrace_pid_add(val);
- set_ftrace_pid_task(ftrace_pid_trace);
- }
-
- /* update the function call */
- ftrace_update_pid_func();
- ftrace_startup_enable(0);
+ return ret ? ret : cnt;
+}
- out:
- mutex_unlock(&ftrace_lock);
+static int
+ftrace_pid_release(struct inode *inode, struct file *file)
+{
+ if (file->f_mode & FMODE_READ)
+ seq_release(inode, file);
- return cnt;
+ return 0;
}
static const struct file_operations ftrace_pid_fops = {
- .read = ftrace_pid_read,
- .write = ftrace_pid_write,
+ .open = ftrace_pid_open,
+ .write = ftrace_pid_write,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = ftrace_pid_release,
};
static __init int ftrace_init_debugfs(void)
{
struct dentry *d_tracer;
- struct dentry *entry;
d_tracer = tracing_init_dentry();
if (!d_tracer)
ftrace_init_dyn_debugfs(d_tracer);
- entry = debugfs_create_file("set_ftrace_pid", 0644, d_tracer,
- NULL, &ftrace_pid_fops);
- if (!entry)
- pr_warning("Could not create debugfs "
- "'set_ftrace_pid' entry\n");
+ trace_create_file("set_ftrace_pid", 0644, d_tracer,
+ NULL, &ftrace_pid_fops);
+
+ ftrace_profile_debugfs(d_tracer);
+
return 0;
}
fs_initcall(ftrace_init_debugfs);
int
ftrace_enable_sysctl(struct ctl_table *table, int write,
- struct file *file, void __user *buffer, size_t *lenp,
+ void __user *buffer, size_t *lenp,
loff_t *ppos)
{
int ret;
mutex_lock(&ftrace_lock);
- ret = proc_dointvec(table, write, file, buffer, lenp, ppos);
+ ret = proc_dointvec(table, write, buffer, lenp, ppos);
- if (ret || !write || (last_ftrace_enabled == ftrace_enabled))
+ if (ret || !write || (last_ftrace_enabled == !!ftrace_enabled))
goto out;
- last_ftrace_enabled = ftrace_enabled;
+ last_ftrace_enabled = !!ftrace_enabled;
if (ftrace_enabled) {
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
-static atomic_t ftrace_graph_active;
+static int ftrace_graph_active;
static struct notifier_block ftrace_suspend_notifier;
int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace)
}
if (t->ret_stack == NULL) {
- t->curr_ret_stack = -1;
- /* Make sure IRQs see the -1 first: */
- barrier();
- t->ret_stack = ret_stack_list[start++];
atomic_set(&t->tracing_graph_pause, 0);
atomic_set(&t->trace_overrun, 0);
+ t->curr_ret_stack = -1;
+ /* Make sure the tasks see the -1 first: */
+ smp_wmb();
+ t->ret_stack = ret_stack_list[start++];
}
} while_each_thread(g, t);
return ret;
}
+static void
+ftrace_graph_probe_sched_switch(struct rq *__rq, struct task_struct *prev,
+ struct task_struct *next)
+{
+ unsigned long long timestamp;
+ int index;
+
+ /*
+ * Does the user want to count the time a function was asleep.
+ * If so, do not update the time stamps.
+ */
+ if (trace_flags & TRACE_ITER_SLEEP_TIME)
+ return;
+
+ timestamp = trace_clock_local();
+
+ prev->ftrace_timestamp = timestamp;
+
+ /* only process tasks that we timestamped */
+ if (!next->ftrace_timestamp)
+ return;
+
+ /*
+ * Update all the counters in next to make up for the
+ * time next was sleeping.
+ */
+ timestamp -= next->ftrace_timestamp;
+
+ for (index = next->curr_ret_stack; index >= 0; index--)
+ next->ret_stack[index].calltime += timestamp;
+}
+
/* Allocate a return stack for each task */
static int start_graph_tracing(void)
{
return -ENOMEM;
/* The cpu_boot init_task->ret_stack will never be freed */
- for_each_online_cpu(cpu)
- ftrace_graph_init_task(idle_task(cpu));
+ for_each_online_cpu(cpu) {
+ if (!idle_task(cpu)->ret_stack)
+ ftrace_graph_init_task(idle_task(cpu));
+ }
do {
ret = alloc_retstack_tasklist(ret_stack_list);
} while (ret == -EAGAIN);
+ if (!ret) {
+ ret = register_trace_sched_switch(ftrace_graph_probe_sched_switch);
+ if (ret)
+ pr_info("ftrace_graph: Couldn't activate tracepoint"
+ " probe to kernel_sched_switch\n");
+ }
+
kfree(ret_stack_list);
return ret;
}
mutex_lock(&ftrace_lock);
+ /* we currently allow only one tracer registered at a time */
+ if (ftrace_graph_active) {
+ ret = -EBUSY;
+ goto out;
+ }
+
ftrace_suspend_notifier.notifier_call = ftrace_suspend_notifier_call;
register_pm_notifier(&ftrace_suspend_notifier);
- atomic_inc(&ftrace_graph_active);
+ ftrace_graph_active++;
ret = start_graph_tracing();
if (ret) {
- atomic_dec(&ftrace_graph_active);
+ ftrace_graph_active--;
goto out;
}
{
mutex_lock(&ftrace_lock);
- atomic_dec(&ftrace_graph_active);
+ if (unlikely(!ftrace_graph_active))
+ goto out;
+
+ ftrace_graph_active--;
+ unregister_trace_sched_switch(ftrace_graph_probe_sched_switch);
ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub;
ftrace_graph_entry = ftrace_graph_entry_stub;
ftrace_shutdown(FTRACE_STOP_FUNC_RET);
unregister_pm_notifier(&ftrace_suspend_notifier);
+ out:
mutex_unlock(&ftrace_lock);
}
/* Allocate a return stack for newly created task */
void ftrace_graph_init_task(struct task_struct *t)
{
- if (atomic_read(&ftrace_graph_active)) {
- t->ret_stack = kmalloc(FTRACE_RETFUNC_DEPTH
+ /* Make sure we do not use the parent ret_stack */
+ t->ret_stack = NULL;
+
+ if (ftrace_graph_active) {
+ struct ftrace_ret_stack *ret_stack;
+
+ ret_stack = kmalloc(FTRACE_RETFUNC_DEPTH
* sizeof(struct ftrace_ret_stack),
GFP_KERNEL);
- if (!t->ret_stack)
+ if (!ret_stack)
return;
t->curr_ret_stack = -1;
atomic_set(&t->tracing_graph_pause, 0);
atomic_set(&t->trace_overrun, 0);
- } else
- t->ret_stack = NULL;
+ t->ftrace_timestamp = 0;
+ /* make curr_ret_stack visable before we add the ret_stack */
+ smp_wmb();
+ t->ret_stack = ret_stack;
+ }
}
void ftrace_graph_exit_task(struct task_struct *t)
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff