#include <linux/clocksource.h>
#include <linux/kallsyms.h>
#include <linux/seq_file.h>
+#include <linux/suspend.h>
#include <linux/debugfs.h>
#include <linux/hardirq.h>
#include <linux/kthread.h>
#include <linux/sysctl.h>
#include <linux/ctype.h>
#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 { \
ftrace_kill(); \
} while (0)
+/* hash bits for specific function selection */
+#define FTRACE_HASH_BITS 7
+#define FTRACE_FUNC_HASHSIZE (1 << FTRACE_HASH_BITS)
+
/* ftrace_enabled is a method to turn ftrace on or off */
int ftrace_enabled __read_mostly;
static int last_ftrace_enabled;
-/* set when tracing only a pid */
-struct pid *ftrace_pid_trace;
-static struct pid * const ftrace_swapper_pid = &init_struct_pid;
-
/* Quick disabling of function tracer. */
int function_trace_stop;
*/
static int ftrace_disabled __read_mostly;
-static DEFINE_SPINLOCK(ftrace_lock);
-static DEFINE_MUTEX(ftrace_sysctl_lock);
-static DEFINE_MUTEX(ftrace_start_lock);
+static DEFINE_MUTEX(ftrace_lock);
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;
static int __register_ftrace_function(struct ftrace_ops *ops)
{
- /* should not be called from interrupt context */
- spin_lock(&ftrace_lock);
-
ops->next = ftrace_list;
/*
* We are entering ops into the ftrace_list but another
#endif
}
- spin_unlock(&ftrace_lock);
-
return 0;
}
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);
/*
* If we are removing the last function, then simply point
if (ftrace_list == ops && ops->next == &ftrace_list_end) {
ftrace_trace_function = ftrace_stub;
ftrace_list = &ftrace_list_end;
- goto out;
+ return 0;
}
for (p = &ftrace_list; *p != &ftrace_list_end; p = &(*p)->next)
if (*p == ops)
break;
- if (*p != ops) {
- ret = -1;
- goto out;
- }
+ if (*p != ops)
+ return -1;
*p = (*p)->next;
}
}
- out:
- spin_unlock(&ftrace_lock);
-
- return ret;
+ return 0;
}
static void ftrace_update_pid_func(void)
{
ftrace_func_t func;
- /* should not be called from interrupt context */
- spin_lock(&ftrace_lock);
-
if (ftrace_trace_function == ftrace_stub)
- goto out;
+ return;
func = ftrace_trace_function;
#else
__ftrace_trace_function = func;
#endif
-
- out:
- spin_unlock(&ftrace_lock);
}
-#ifdef CONFIG_DYNAMIC_FTRACE
-#ifndef CONFIG_FTRACE_MCOUNT_RECORD
-# error Dynamic ftrace depends on MCOUNT_RECORD
+#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
-
-/*
- * Since MCOUNT_ADDR may point to mcount itself, we do not want
- * to get it confused by reading a reference in the code as we
- * are parsing on objcopy output of text. Use a variable for
- * it instead.
- */
-static unsigned long mcount_addr = MCOUNT_ADDR;
-
-enum {
- FTRACE_ENABLE_CALLS = (1 << 0),
- FTRACE_DISABLE_CALLS = (1 << 1),
- FTRACE_UPDATE_TRACE_FUNC = (1 << 2),
- FTRACE_ENABLE_MCOUNT = (1 << 3),
- FTRACE_DISABLE_MCOUNT = (1 << 4),
- FTRACE_START_FUNC_RET = (1 << 5),
- FTRACE_STOP_FUNC_RET = (1 << 6),
};
-static int ftrace_filtered;
+struct ftrace_profile_page {
+ struct ftrace_profile_page *next;
+ unsigned long index;
+ struct ftrace_profile records[];
+};
-static LIST_HEAD(ftrace_new_addrs);
+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;
+};
-static DEFINE_MUTEX(ftrace_regex_lock);
+#define PROFILE_RECORDS_SIZE \
+ (PAGE_SIZE - offsetof(struct ftrace_profile_page, records))
-struct ftrace_page {
- struct ftrace_page *next;
- unsigned long index;
- struct dyn_ftrace records[];
-};
+#define PROFILES_PER_PAGE \
+ (PROFILE_RECORDS_SIZE / sizeof(struct ftrace_profile))
-#define ENTRIES_PER_PAGE \
- ((PAGE_SIZE - sizeof(struct ftrace_page)) / sizeof(struct dyn_ftrace))
+static int ftrace_profile_bits __read_mostly;
+static int ftrace_profile_enabled __read_mostly;
-/* estimate from running different kernels */
-#define NR_TO_INIT 10000
+/* ftrace_profile_lock - synchronize the enable and disable of the profiler */
+static DEFINE_MUTEX(ftrace_profile_lock);
-static struct ftrace_page *ftrace_pages_start;
-static struct ftrace_page *ftrace_pages;
+static DEFINE_PER_CPU(struct ftrace_profile_stat, ftrace_profile_stats);
-static struct dyn_ftrace *ftrace_free_records;
+#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;
-#ifdef CONFIG_KPROBES
+ pg = (struct ftrace_profile_page *)((unsigned long)rec & PAGE_MASK);
-static int frozen_record_count;
+ again:
+ if (idx != 0)
+ rec++;
-static inline void freeze_record(struct dyn_ftrace *rec)
-{
- if (!(rec->flags & FTRACE_FL_FROZEN)) {
- rec->flags |= FTRACE_FL_FROZEN;
- frozen_record_count++;
+ 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 inline void unfreeze_record(struct dyn_ftrace *rec)
+static void *function_stat_start(struct tracer_stat *trace)
{
- if (rec->flags & FTRACE_FL_FROZEN) {
- rec->flags &= ~FTRACE_FL_FROZEN;
- frozen_record_count--;
- }
+ 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);
}
-static inline int record_frozen(struct dyn_ftrace *rec)
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+/* function graph compares on total time */
+static int function_stat_cmp(void *p1, void *p2)
{
- return rec->flags & FTRACE_FL_FROZEN;
+ 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
-# define freeze_record(rec) ({ 0; })
-# define unfreeze_record(rec) ({ 0; })
-# define record_frozen(rec) ({ 0; })
-#endif /* CONFIG_KPROBES */
-
-static void ftrace_free_rec(struct dyn_ftrace *rec)
+/* not function graph compares against hits */
+static int function_stat_cmp(void *p1, void *p2)
{
- rec->ip = (unsigned long)ftrace_free_records;
- ftrace_free_records = rec;
- rec->flags |= FTRACE_FL_FREE;
+ 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
-void ftrace_release(void *start, unsigned long size)
+static int function_stat_headers(struct seq_file *m)
{
- struct dyn_ftrace *rec;
- struct ftrace_page *pg;
- unsigned long s = (unsigned long)start;
- unsigned long e = s + size;
- int i;
+#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;
+}
- if (ftrace_disabled || !start)
- return;
+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
- /* should not be called from interrupt context */
- spin_lock(&ftrace_lock);
+ kallsyms_lookup(rec->ip, NULL, NULL, NULL, str);
+ seq_printf(m, " %-30.30s %10lu", str, rec->counter);
- for (pg = ftrace_pages_start; pg; pg = pg->next) {
- for (i = 0; i < pg->index; i++) {
- rec = &pg->records[i];
+#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');
- if ((rec->ip >= s) && (rec->ip < e))
- ftrace_free_rec(rec);
- }
- }
- spin_unlock(&ftrace_lock);
+ return 0;
}
-static struct dyn_ftrace *ftrace_alloc_dyn_node(unsigned long ip)
+static void ftrace_profile_reset(struct ftrace_profile_stat *stat)
{
- struct dyn_ftrace *rec;
-
- /* First check for freed records */
- if (ftrace_free_records) {
- rec = ftrace_free_records;
-
- if (unlikely(!(rec->flags & FTRACE_FL_FREE))) {
- FTRACE_WARN_ON_ONCE(1);
- ftrace_free_records = NULL;
- return NULL;
- }
+ struct ftrace_profile_page *pg;
- ftrace_free_records = (void *)rec->ip;
- memset(rec, 0, sizeof(*rec));
- return rec;
- }
+ pg = stat->pages = stat->start;
- if (ftrace_pages->index == ENTRIES_PER_PAGE) {
- if (!ftrace_pages->next) {
- /* allocate another page */
- ftrace_pages->next =
- (void *)get_zeroed_page(GFP_KERNEL);
- if (!ftrace_pages->next)
- return NULL;
- }
- ftrace_pages = ftrace_pages->next;
+ while (pg) {
+ memset(pg->records, 0, PROFILE_RECORDS_SIZE);
+ pg->index = 0;
+ pg = pg->next;
}
- return &ftrace_pages->records[ftrace_pages->index++];
+ memset(stat->hash, 0,
+ FTRACE_PROFILE_HASH_SIZE * sizeof(struct hlist_head));
}
-static struct dyn_ftrace *
-ftrace_record_ip(unsigned long ip)
+int ftrace_profile_pages_init(struct ftrace_profile_stat *stat)
{
- struct dyn_ftrace *rec;
+ struct ftrace_profile_page *pg;
+ int functions;
+ int pages;
+ int i;
- if (ftrace_disabled)
- return NULL;
+ /* If we already allocated, do nothing */
+ if (stat->pages)
+ return 0;
- rec = ftrace_alloc_dyn_node(ip);
- if (!rec)
- return NULL;
+ stat->pages = (void *)get_zeroed_page(GFP_KERNEL);
+ if (!stat->pages)
+ return -ENOMEM;
- rec->ip = ip;
+#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
- list_add(&rec->list, &ftrace_new_addrs);
+ pg = stat->start = stat->pages;
- return rec;
-}
+ pages = DIV_ROUND_UP(functions, PROFILES_PER_PAGE);
-static void print_ip_ins(const char *fmt, unsigned char *p)
-{
- int i;
+ for (i = 0; i < pages; i++) {
+ pg->next = (void *)get_zeroed_page(GFP_KERNEL);
+ if (!pg->next)
+ goto out_free;
+ pg = pg->next;
+ }
- printk(KERN_CONT "%s", fmt);
+ return 0;
- for (i = 0; i < MCOUNT_INSN_SIZE; i++)
- printk(KERN_CONT "%s%02x", i ? ":" : "", p[i]);
-}
+ out_free:
+ pg = stat->start;
+ while (pg) {
+ unsigned long tmp = (unsigned long)pg;
-static void ftrace_bug(int failed, unsigned long ip)
-{
- switch (failed) {
- case -EFAULT:
- FTRACE_WARN_ON_ONCE(1);
- pr_info("ftrace faulted on modifying ");
- print_ip_sym(ip);
- break;
- case -EINVAL:
- FTRACE_WARN_ON_ONCE(1);
- pr_info("ftrace failed to modify ");
- print_ip_sym(ip);
- print_ip_ins(" actual: ", (unsigned char *)ip);
- printk(KERN_CONT "\n");
- break;
- case -EPERM:
- FTRACE_WARN_ON_ONCE(1);
- pr_info("ftrace faulted on writing ");
- print_ip_sym(ip);
- break;
- default:
- FTRACE_WARN_ON_ONCE(1);
- pr_info("ftrace faulted on unknown error ");
- print_ip_sym(ip);
+ pg = pg->next;
+ free_page(tmp);
}
-}
+ free_page((unsigned long)stat->pages);
+ stat->pages = NULL;
+ stat->start = NULL;
-static int
-__ftrace_replace_code(struct dyn_ftrace *rec, int enable)
+ return -ENOMEM;
+}
+
+static int ftrace_profile_init_cpu(int cpu)
{
- unsigned long ip, fl;
- unsigned long ftrace_addr;
+ struct ftrace_profile_stat *stat;
+ int size;
- ftrace_addr = (unsigned long)ftrace_caller;
+ stat = &per_cpu(ftrace_profile_stats, cpu);
- ip = rec->ip;
+ if (stat->hash) {
+ /* If the profile is already created, simply reset it */
+ ftrace_profile_reset(stat);
+ return 0;
+ }
/*
- * If this record is not to be traced and
- * it is not enabled then do nothing.
- *
- * If this record is not to be traced and
- * it is enabled then disabled it.
- *
+ * We are profiling all functions, but usually only a few thousand
+ * functions are hit. We'll make a hash of 1024 items.
*/
- 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:
- */
+ size = FTRACE_PROFILE_HASH_SIZE;
- fl = rec->flags & (FTRACE_FL_FILTER | FTRACE_FL_ENABLED);
+ stat->hash = kzalloc(sizeof(struct hlist_head) * size, GFP_KERNEL);
- /* Record is filtered and enabled, do nothing */
- if (fl == (FTRACE_FL_FILTER | FTRACE_FL_ENABLED))
- return 0;
-
- /* Record is not filtered and is not enabled do nothing */
- if (!fl)
- return 0;
+ if (!stat->hash)
+ return -ENOMEM;
- /* 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 (!ftrace_profile_bits) {
+ size--;
- if (enable) {
- /* if record is enabled, do nothing */
- if (rec->flags & FTRACE_FL_ENABLED)
- return 0;
+ for (; size; size >>= 1)
+ ftrace_profile_bits++;
+ }
- rec->flags |= FTRACE_FL_ENABLED;
+ /* Preallocate the function profiling pages */
+ if (ftrace_profile_pages_init(stat) < 0) {
+ kfree(stat->hash);
+ stat->hash = NULL;
+ return -ENOMEM;
+ }
- } else {
+ return 0;
+}
- /* if record is not enabled do nothing */
- if (!(rec->flags & FTRACE_FL_ENABLED))
- return 0;
+static int ftrace_profile_init(void)
+{
+ int cpu;
+ int ret = 0;
- rec->flags &= ~FTRACE_FL_ENABLED;
- }
+ for_each_online_cpu(cpu) {
+ ret = ftrace_profile_init_cpu(cpu);
+ if (ret)
+ break;
}
- if (rec->flags & FTRACE_FL_ENABLED)
- return ftrace_make_call(rec, ftrace_addr);
- else
- return ftrace_make_nop(NULL, rec, ftrace_addr);
+ return ret;
}
-static void ftrace_replace_code(int enable)
+/* interrupts must be disabled */
+static struct ftrace_profile *
+ftrace_find_profiled_func(struct ftrace_profile_stat *stat, unsigned long ip)
{
- int i, failed;
- struct dyn_ftrace *rec;
- struct ftrace_page *pg;
-
- for (pg = ftrace_pages_start; pg; pg = pg->next) {
- for (i = 0; i < pg->index; i++) {
- rec = &pg->records[i];
+ struct ftrace_profile *rec;
+ struct hlist_head *hhd;
+ struct hlist_node *n;
+ unsigned long key;
- /*
- * Skip over free records and records that have
- * failed.
- */
- if (rec->flags & FTRACE_FL_FREE ||
- rec->flags & FTRACE_FL_FAILED)
- continue;
+ key = hash_long(ip, ftrace_profile_bits);
+ hhd = &stat->hash[key];
- /* ignore updates to this record's mcount site */
- if (get_kprobe((void *)rec->ip)) {
- freeze_record(rec);
- continue;
- } else {
- unfreeze_record(rec);
- }
+ if (hlist_empty(hhd))
+ return NULL;
- failed = __ftrace_replace_code(rec, enable);
- if (failed && (rec->flags & FTRACE_FL_CONVERTED)) {
- 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);
- }
- }
+ hlist_for_each_entry_rcu(rec, n, hhd, node) {
+ if (rec->ip == ip)
+ return rec;
}
+
+ return NULL;
}
-static int
-ftrace_code_disable(struct module *mod, struct dyn_ftrace *rec)
+static void ftrace_add_profile(struct ftrace_profile_stat *stat,
+ struct ftrace_profile *rec)
{
- unsigned long ip;
- int ret;
+ unsigned long key;
- ip = rec->ip;
+ key = hash_long(rec->ip, ftrace_profile_bits);
+ hlist_add_head_rcu(&rec->node, &stat->hash[key]);
+}
- ret = ftrace_make_nop(mod, rec, mcount_addr);
+/*
+ * 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);
+
+ filp->f_pos += 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 */
+
+/* set when tracing only a pid */
+struct pid *ftrace_pid_trace;
+static struct pid * const ftrace_swapper_pid = &init_struct_pid;
+
+#ifdef CONFIG_DYNAMIC_FTRACE
+
+#ifndef CONFIG_FTRACE_MCOUNT_RECORD
+# error Dynamic ftrace depends on MCOUNT_RECORD
+#endif
+
+static struct hlist_head ftrace_func_hash[FTRACE_FUNC_HASHSIZE] __read_mostly;
+
+struct ftrace_func_probe {
+ struct hlist_node node;
+ struct ftrace_probe_ops *ops;
+ unsigned long flags;
+ unsigned long ip;
+ void *data;
+ struct rcu_head rcu;
+};
+
+enum {
+ FTRACE_ENABLE_CALLS = (1 << 0),
+ FTRACE_DISABLE_CALLS = (1 << 1),
+ FTRACE_UPDATE_TRACE_FUNC = (1 << 2),
+ FTRACE_ENABLE_MCOUNT = (1 << 3),
+ FTRACE_DISABLE_MCOUNT = (1 << 4),
+ FTRACE_START_FUNC_RET = (1 << 5),
+ FTRACE_STOP_FUNC_RET = (1 << 6),
+};
+
+static int ftrace_filtered;
+
+static struct dyn_ftrace *ftrace_new_addrs;
+
+static DEFINE_MUTEX(ftrace_regex_lock);
+
+struct ftrace_page {
+ struct ftrace_page *next;
+ int index;
+ struct dyn_ftrace records[];
+};
+
+#define ENTRIES_PER_PAGE \
+ ((PAGE_SIZE - sizeof(struct ftrace_page)) / sizeof(struct dyn_ftrace))
+
+/* estimate from running different kernels */
+#define NR_TO_INIT 10000
+
+static struct ftrace_page *ftrace_pages_start;
+static struct ftrace_page *ftrace_pages;
+
+static struct dyn_ftrace *ftrace_free_records;
+
+/*
+ * This is a double for. Do not use 'break' to break out of the loop,
+ * you must use a goto.
+ */
+#define do_for_each_ftrace_rec(pg, rec) \
+ for (pg = ftrace_pages_start; pg; pg = pg->next) { \
+ int _____i; \
+ for (_____i = 0; _____i < pg->index; _____i++) { \
+ rec = &pg->records[_____i];
+
+#define while_for_each_ftrace_rec() \
+ } \
+ }
+
+#ifdef CONFIG_KPROBES
+
+static int frozen_record_count;
+
+static inline void freeze_record(struct dyn_ftrace *rec)
+{
+ if (!(rec->flags & FTRACE_FL_FROZEN)) {
+ rec->flags |= FTRACE_FL_FROZEN;
+ frozen_record_count++;
+ }
+}
+
+static inline void unfreeze_record(struct dyn_ftrace *rec)
+{
+ if (rec->flags & FTRACE_FL_FROZEN) {
+ rec->flags &= ~FTRACE_FL_FROZEN;
+ frozen_record_count--;
+ }
+}
+
+static inline int record_frozen(struct dyn_ftrace *rec)
+{
+ return rec->flags & FTRACE_FL_FROZEN;
+}
+#else
+# define freeze_record(rec) ({ 0; })
+# define unfreeze_record(rec) ({ 0; })
+# define record_frozen(rec) ({ 0; })
+#endif /* CONFIG_KPROBES */
+
+static void ftrace_free_rec(struct dyn_ftrace *rec)
+{
+ rec->freelist = ftrace_free_records;
+ ftrace_free_records = rec;
+ rec->flags |= FTRACE_FL_FREE;
+}
+
+static struct dyn_ftrace *ftrace_alloc_dyn_node(unsigned long ip)
+{
+ struct dyn_ftrace *rec;
+
+ /* First check for freed records */
+ if (ftrace_free_records) {
+ rec = ftrace_free_records;
+
+ if (unlikely(!(rec->flags & FTRACE_FL_FREE))) {
+ FTRACE_WARN_ON_ONCE(1);
+ ftrace_free_records = NULL;
+ return NULL;
+ }
+
+ ftrace_free_records = rec->freelist;
+ memset(rec, 0, sizeof(*rec));
+ return rec;
+ }
+
+ if (ftrace_pages->index == ENTRIES_PER_PAGE) {
+ if (!ftrace_pages->next) {
+ /* allocate another page */
+ ftrace_pages->next =
+ (void *)get_zeroed_page(GFP_KERNEL);
+ if (!ftrace_pages->next)
+ return NULL;
+ }
+ ftrace_pages = ftrace_pages->next;
+ }
+
+ return &ftrace_pages->records[ftrace_pages->index++];
+}
+
+static struct dyn_ftrace *
+ftrace_record_ip(unsigned long ip)
+{
+ struct dyn_ftrace *rec;
+
+ if (ftrace_disabled)
+ return NULL;
+
+ rec = ftrace_alloc_dyn_node(ip);
+ if (!rec)
+ return NULL;
+
+ rec->ip = ip;
+ rec->newlist = ftrace_new_addrs;
+ ftrace_new_addrs = rec;
+
+ return rec;
+}
+
+static void print_ip_ins(const char *fmt, unsigned char *p)
+{
+ int i;
+
+ printk(KERN_CONT "%s", fmt);
+
+ for (i = 0; i < MCOUNT_INSN_SIZE; i++)
+ printk(KERN_CONT "%s%02x", i ? ":" : "", p[i]);
+}
+
+static void ftrace_bug(int failed, unsigned long ip)
+{
+ switch (failed) {
+ case -EFAULT:
+ FTRACE_WARN_ON_ONCE(1);
+ pr_info("ftrace faulted on modifying ");
+ print_ip_sym(ip);
+ break;
+ case -EINVAL:
+ FTRACE_WARN_ON_ONCE(1);
+ pr_info("ftrace failed to modify ");
+ print_ip_sym(ip);
+ print_ip_ins(" actual: ", (unsigned char *)ip);
+ printk(KERN_CONT "\n");
+ break;
+ case -EPERM:
+ FTRACE_WARN_ON_ONCE(1);
+ pr_info("ftrace faulted on writing ");
+ print_ip_sym(ip);
+ break;
+ default:
+ FTRACE_WARN_ON_ONCE(1);
+ pr_info("ftrace faulted on unknown error ");
+ print_ip_sym(ip);
+ }
+}
+
+
+static int
+__ftrace_replace_code(struct dyn_ftrace *rec, int enable)
+{
+ unsigned long ftrace_addr;
+ unsigned long flag = 0UL;
+
+ ftrace_addr = (unsigned long)FTRACE_ADDR;
+
+ /*
+ * If this record is not to be traced or we want to disable it,
+ * 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 (enable && !(rec->flags & FTRACE_FL_NOTRACE)) {
+ if (!ftrace_filtered || (rec->flags & FTRACE_FL_FILTER))
+ flag = FTRACE_FL_ENABLED;
+ }
+
+ /* If the state of this record hasn't changed, then do nothing */
+ if ((rec->flags & FTRACE_FL_ENABLED) == flag)
+ return 0;
+
+ if (flag) {
+ rec->flags |= FTRACE_FL_ENABLED;
+ return ftrace_make_call(rec, ftrace_addr);
+ }
+
+ rec->flags &= ~FTRACE_FL_ENABLED;
+ return ftrace_make_nop(NULL, rec, ftrace_addr);
+}
+
+static void ftrace_replace_code(int enable)
+{
+ struct dyn_ftrace *rec;
+ struct ftrace_page *pg;
+ int failed;
+
+ do_for_each_ftrace_rec(pg, rec) {
+ /*
+ * Skip over free records, records that have
+ * failed and not converted.
+ */
+ if (rec->flags & FTRACE_FL_FREE ||
+ rec->flags & FTRACE_FL_FAILED ||
+ !(rec->flags & FTRACE_FL_CONVERTED))
+ continue;
+
+ /* ignore updates to this record's mcount site */
+ if (get_kprobe((void *)rec->ip)) {
+ freeze_record(rec);
+ continue;
+ } else {
+ unfreeze_record(rec);
+ }
+
+ 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;
+ }
+ }
+ } while_for_each_ftrace_rec();
+}
+
+static int
+ftrace_code_disable(struct module *mod, struct dyn_ftrace *rec)
+{
+ unsigned long ip;
+ int ret;
+
+ ip = rec->ip;
+
+ ret = ftrace_make_nop(mod, rec, MCOUNT_ADDR);
if (ret) {
ftrace_bug(ret, ip);
rec->flags |= FTRACE_FL_FAILED;
return 0;
}
- return 1;
+ return 1;
+}
+
+/*
+ * archs can override this function if they must do something
+ * before the modifying code is performed.
+ */
+int __weak ftrace_arch_code_modify_prepare(void)
+{
+ return 0;
+}
+
+/*
+ * archs can override this function if they must do something
+ * after the modifying code is performed.
+ */
+int __weak ftrace_arch_code_modify_post_process(void)
+{
+ return 0;
+}
+
+static int __ftrace_modify_code(void *data)
+{
+ int *command = data;
+
+ if (*command & FTRACE_ENABLE_CALLS)
+ ftrace_replace_code(1);
+ else if (*command & FTRACE_DISABLE_CALLS)
+ ftrace_replace_code(0);
+
+ if (*command & FTRACE_UPDATE_TRACE_FUNC)
+ ftrace_update_ftrace_func(ftrace_trace_function);
+
+ if (*command & FTRACE_START_FUNC_RET)
+ ftrace_enable_ftrace_graph_caller();
+ else if (*command & FTRACE_STOP_FUNC_RET)
+ ftrace_disable_ftrace_graph_caller();
+
+ return 0;
+}
+
+static void ftrace_run_update_code(int command)
+{
+ int ret;
+
+ ret = ftrace_arch_code_modify_prepare();
+ FTRACE_WARN_ON(ret);
+ if (ret)
+ return;
+
+ stop_machine(__ftrace_modify_code, &command, NULL);
+
+ ret = ftrace_arch_code_modify_post_process();
+ FTRACE_WARN_ON(ret);
+}
+
+static ftrace_func_t saved_ftrace_func;
+static int ftrace_start_up;
+
+static void ftrace_startup_enable(int command)
+{
+ if (saved_ftrace_func != ftrace_trace_function) {
+ saved_ftrace_func = ftrace_trace_function;
+ command |= FTRACE_UPDATE_TRACE_FUNC;
+ }
+
+ if (!command || !ftrace_enabled)
+ return;
+
+ ftrace_run_update_code(command);
+}
+
+static void ftrace_startup(int command)
+{
+ if (unlikely(ftrace_disabled))
+ return;
+
+ ftrace_start_up++;
+ command |= FTRACE_ENABLE_CALLS;
+
+ ftrace_startup_enable(command);
+}
+
+static void ftrace_shutdown(int command)
+{
+ if (unlikely(ftrace_disabled))
+ 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;
+
+ if (saved_ftrace_func != ftrace_trace_function) {
+ saved_ftrace_func = ftrace_trace_function;
+ command |= FTRACE_UPDATE_TRACE_FUNC;
+ }
+
+ if (!command || !ftrace_enabled)
+ return;
+
+ ftrace_run_update_code(command);
+}
+
+static void ftrace_startup_sysctl(void)
+{
+ int command = FTRACE_ENABLE_MCOUNT;
+
+ if (unlikely(ftrace_disabled))
+ return;
+
+ /* Force update next time */
+ saved_ftrace_func = NULL;
+ /* ftrace_start_up is true if we want ftrace running */
+ if (ftrace_start_up)
+ command |= FTRACE_ENABLE_CALLS;
+
+ ftrace_run_update_code(command);
+}
+
+static void ftrace_shutdown_sysctl(void)
+{
+ int command = FTRACE_DISABLE_MCOUNT;
+
+ if (unlikely(ftrace_disabled))
+ return;
+
+ /* ftrace_start_up is true if ftrace is running */
+ if (ftrace_start_up)
+ command |= FTRACE_DISABLE_CALLS;
+
+ ftrace_run_update_code(command);
+}
+
+static cycle_t ftrace_update_time;
+static unsigned long ftrace_update_cnt;
+unsigned long ftrace_update_tot_cnt;
+
+static int ftrace_update_code(struct module *mod)
+{
+ struct dyn_ftrace *p;
+ cycle_t start, stop;
+
+ start = ftrace_now(raw_smp_processor_id());
+ ftrace_update_cnt = 0;
+
+ while (ftrace_new_addrs) {
+
+ /* If something went wrong, bail without enabling anything */
+ if (unlikely(ftrace_disabled))
+ return -1;
+
+ p = ftrace_new_addrs;
+ 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
+ ftrace_free_rec(p);
+ }
+
+ stop = ftrace_now(raw_smp_processor_id());
+ ftrace_update_time = stop - start;
+ ftrace_update_tot_cnt += ftrace_update_cnt;
+
+ return 0;
+}
+
+static int __init ftrace_dyn_table_alloc(unsigned long num_to_init)
+{
+ struct ftrace_page *pg;
+ int cnt;
+ int i;
+
+ /* allocate a few pages */
+ ftrace_pages_start = (void *)get_zeroed_page(GFP_KERNEL);
+ if (!ftrace_pages_start)
+ return -1;
+
+ /*
+ * Allocate a few more pages.
+ *
+ * TODO: have some parser search vmlinux before
+ * final linking to find all calls to ftrace.
+ * Then we can:
+ * a) know how many pages to allocate.
+ * and/or
+ * b) set up the table then.
+ *
+ * The dynamic code is still necessary for
+ * modules.
+ */
+
+ pg = ftrace_pages = ftrace_pages_start;
+
+ cnt = num_to_init / ENTRIES_PER_PAGE;
+ pr_info("ftrace: allocating %ld entries in %d pages\n",
+ num_to_init, cnt + 1);
+
+ for (i = 0; i < cnt; i++) {
+ pg->next = (void *)get_zeroed_page(GFP_KERNEL);
+
+ /* If we fail, we'll try later anyway */
+ if (!pg->next)
+ break;
+
+ pg = pg->next;
+ }
+
+ return 0;
+}
+
+enum {
+ FTRACE_ITER_FILTER = (1 << 0),
+ 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 */
+
+struct ftrace_iterator {
+ struct ftrace_page *pg;
+ int hidx;
+ int idx;
+ unsigned flags;
+ struct trace_parser parser;
+};
+
+static void *
+t_hash_next(struct seq_file *m, void *v, loff_t *pos)
+{
+ struct ftrace_iterator *iter = m->private;
+ struct hlist_node *hnd = v;
+ struct hlist_head *hhd;
+
+ WARN_ON(!(iter->flags & FTRACE_ITER_HASH));
+
+ (*pos)++;
+
+ retry:
+ if (iter->hidx >= FTRACE_FUNC_HASHSIZE)
+ return NULL;
+
+ hhd = &ftrace_func_hash[iter->hidx];
+
+ if (hlist_empty(hhd)) {
+ iter->hidx++;
+ hnd = NULL;
+ goto retry;
+ }
+
+ if (!hnd)
+ hnd = hhd->first;
+ else {
+ hnd = hnd->next;
+ if (!hnd) {
+ iter->hidx++;
+ goto retry;
+ }
+ }
+
+ return hnd;
+}
+
+static void *t_hash_start(struct seq_file *m, loff_t *pos)
+{
+ 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;
+
+ 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;
+
+ rec = hlist_entry(hnd, struct ftrace_func_probe, node);
+
+ if (rec->ops->print)
+ return rec->ops->print(m, rec->ip, rec->ops, rec->data);
+
+ seq_printf(m, "%ps:%ps", (void *)rec->ip, (void *)rec->ops->func);
+
+ if (rec->data)
+ seq_printf(m, ":%p", rec->data);
+ seq_putc(m, '\n');
+
+ return 0;
+}
+
+static void *
+t_next(struct seq_file *m, void *v, loff_t *pos)
+{
+ struct ftrace_iterator *iter = m->private;
+ struct dyn_ftrace *rec = NULL;
+
+ if (iter->flags & FTRACE_ITER_HASH)
+ return t_hash_next(m, v, pos);
+
+ (*pos)++;
+
+ if (iter->flags & FTRACE_ITER_PRINTALL)
+ return NULL;
+
+ retry:
+ if (iter->idx >= iter->pg->index) {
+ if (iter->pg->next) {
+ iter->pg = iter->pg->next;
+ iter->idx = 0;
+ goto retry;
+ }
+ } else {
+ rec = &iter->pg->records[iter->idx++];
+ if ((rec->flags & FTRACE_FL_FREE) ||
+
+ (!(iter->flags & FTRACE_ITER_FAILURES) &&
+ (rec->flags & FTRACE_FL_FAILED)) ||
+
+ ((iter->flags & FTRACE_ITER_FAILURES) &&
+ !(rec->flags & FTRACE_FL_FAILED)) ||
+
+ ((iter->flags & FTRACE_ITER_FILTER) &&
+ !(rec->flags & FTRACE_FL_FILTER)) ||
+
+ ((iter->flags & FTRACE_ITER_NOTRACE) &&
+ !(rec->flags & FTRACE_FL_NOTRACE))) {
+ rec = NULL;
+ goto retry;
+ }
+ }
+
+ return rec;
}
-static int __ftrace_modify_code(void *data)
+static void *t_start(struct seq_file *m, loff_t *pos)
{
- int *command = data;
+ struct ftrace_iterator *iter = m->private;
+ void *p = NULL;
+ loff_t l;
- if (*command & FTRACE_ENABLE_CALLS)
- ftrace_replace_code(1);
- else if (*command & FTRACE_DISABLE_CALLS)
- ftrace_replace_code(0);
+ mutex_lock(&ftrace_lock);
+ /*
+ * For set_ftrace_filter reading, if we have the filter
+ * off, we can short cut and just print out that all
+ * functions are enabled.
+ */
+ if (iter->flags & FTRACE_ITER_FILTER && !ftrace_filtered) {
+ if (*pos > 0)
+ return t_hash_start(m, pos);
+ iter->flags |= FTRACE_ITER_PRINTALL;
+ return iter;
+ }
- if (*command & FTRACE_UPDATE_TRACE_FUNC)
- ftrace_update_ftrace_func(ftrace_trace_function);
+ if (iter->flags & FTRACE_ITER_HASH)
+ return t_hash_start(m, pos);
- if (*command & FTRACE_START_FUNC_RET)
- ftrace_enable_ftrace_graph_caller();
- else if (*command & FTRACE_STOP_FUNC_RET)
- ftrace_disable_ftrace_graph_caller();
+ iter->pg = ftrace_pages_start;
+ iter->idx = 0;
+ for (l = 0; l <= *pos; ) {
+ p = t_next(m, p, &l);
+ if (!p)
+ break;
+ }
- return 0;
+ if (!p && iter->flags & FTRACE_ITER_FILTER)
+ return t_hash_start(m, pos);
+
+ return p;
}
-static void ftrace_run_update_code(int command)
+static void t_stop(struct seq_file *m, void *p)
{
- stop_machine(__ftrace_modify_code, &command, NULL);
+ mutex_unlock(&ftrace_lock);
}
-static ftrace_func_t saved_ftrace_func;
-static int ftrace_start_up;
-
-static void ftrace_startup_enable(int command)
+static int t_show(struct seq_file *m, void *v)
{
- if (saved_ftrace_func != ftrace_trace_function) {
- saved_ftrace_func = ftrace_trace_function;
- command |= FTRACE_UPDATE_TRACE_FUNC;
+ struct ftrace_iterator *iter = m->private;
+ struct dyn_ftrace *rec = v;
+
+ if (iter->flags & FTRACE_ITER_HASH)
+ return t_hash_show(m, v);
+
+ if (iter->flags & FTRACE_ITER_PRINTALL) {
+ seq_printf(m, "#### all functions enabled ####\n");
+ return 0;
}
- if (!command || !ftrace_enabled)
- return;
+ if (!rec)
+ return 0;
- ftrace_run_update_code(command);
+ seq_printf(m, "%ps\n", (void *)rec->ip);
+
+ return 0;
}
-static void ftrace_startup(int command)
+static const struct seq_operations show_ftrace_seq_ops = {
+ .start = t_start,
+ .next = t_next,
+ .stop = t_stop,
+ .show = t_show,
+};
+
+static int
+ftrace_avail_open(struct inode *inode, struct file *file)
{
+ struct ftrace_iterator *iter;
+ int ret;
+
if (unlikely(ftrace_disabled))
- return;
+ return -ENODEV;
- mutex_lock(&ftrace_start_lock);
- ftrace_start_up++;
- command |= FTRACE_ENABLE_CALLS;
+ iter = kzalloc(sizeof(*iter), GFP_KERNEL);
+ if (!iter)
+ return -ENOMEM;
- ftrace_startup_enable(command);
+ iter->pg = ftrace_pages_start;
+
+ ret = seq_open(file, &show_ftrace_seq_ops);
+ if (!ret) {
+ struct seq_file *m = file->private_data;
+
+ m->private = iter;
+ } else {
+ kfree(iter);
+ }
- mutex_unlock(&ftrace_start_lock);
+ return ret;
}
-static void ftrace_shutdown(int command)
+static int
+ftrace_failures_open(struct inode *inode, struct file *file)
{
- if (unlikely(ftrace_disabled))
- return;
-
- mutex_lock(&ftrace_start_lock);
- ftrace_start_up--;
- if (!ftrace_start_up)
- command |= FTRACE_DISABLE_CALLS;
+ int ret;
+ struct seq_file *m;
+ struct ftrace_iterator *iter;
- if (saved_ftrace_func != ftrace_trace_function) {
- saved_ftrace_func = ftrace_trace_function;
- command |= FTRACE_UPDATE_TRACE_FUNC;
+ ret = ftrace_avail_open(inode, file);
+ if (!ret) {
+ m = (struct seq_file *)file->private_data;
+ iter = (struct ftrace_iterator *)m->private;
+ iter->flags = FTRACE_ITER_FAILURES;
}
- if (!command || !ftrace_enabled)
- goto out;
-
- ftrace_run_update_code(command);
- out:
- mutex_unlock(&ftrace_start_lock);
+ return ret;
}
-static void ftrace_startup_sysctl(void)
-{
- int command = FTRACE_ENABLE_MCOUNT;
-
- if (unlikely(ftrace_disabled))
- return;
- mutex_lock(&ftrace_start_lock);
- /* Force update next time */
- saved_ftrace_func = NULL;
- /* ftrace_start_up is true if we want ftrace running */
- if (ftrace_start_up)
- command |= FTRACE_ENABLE_CALLS;
+static void ftrace_filter_reset(int enable)
+{
+ struct ftrace_page *pg;
+ struct dyn_ftrace *rec;
+ unsigned long type = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE;
- ftrace_run_update_code(command);
- mutex_unlock(&ftrace_start_lock);
+ mutex_lock(&ftrace_lock);
+ if (enable)
+ ftrace_filtered = 0;
+ do_for_each_ftrace_rec(pg, rec) {
+ if (rec->flags & FTRACE_FL_FAILED)
+ continue;
+ rec->flags &= ~type;
+ } while_for_each_ftrace_rec();
+ mutex_unlock(&ftrace_lock);
}
-static void ftrace_shutdown_sysctl(void)
+static int
+ftrace_regex_open(struct inode *inode, struct file *file, int enable)
{
- int command = FTRACE_DISABLE_MCOUNT;
+ struct ftrace_iterator *iter;
+ int ret = 0;
if (unlikely(ftrace_disabled))
- return;
+ return -ENODEV;
- mutex_lock(&ftrace_start_lock);
- /* ftrace_start_up is true if ftrace is running */
- if (ftrace_start_up)
- command |= FTRACE_DISABLE_CALLS;
+ iter = kzalloc(sizeof(*iter), GFP_KERNEL);
+ if (!iter)
+ return -ENOMEM;
- ftrace_run_update_code(command);
- mutex_unlock(&ftrace_start_lock);
-}
+ if (trace_parser_get_init(&iter->parser, FTRACE_BUFF_MAX)) {
+ kfree(iter);
+ return -ENOMEM;
+ }
-static cycle_t ftrace_update_time;
-static unsigned long ftrace_update_cnt;
-unsigned long ftrace_update_tot_cnt;
+ mutex_lock(&ftrace_regex_lock);
+ if ((file->f_mode & FMODE_WRITE) &&
+ (file->f_flags & O_TRUNC))
+ ftrace_filter_reset(enable);
-static int ftrace_update_code(struct module *mod)
-{
- struct dyn_ftrace *p, *t;
- cycle_t start, stop;
+ if (file->f_mode & FMODE_READ) {
+ iter->pg = ftrace_pages_start;
+ iter->flags = enable ? FTRACE_ITER_FILTER :
+ FTRACE_ITER_NOTRACE;
- start = ftrace_now(raw_smp_processor_id());
- ftrace_update_cnt = 0;
+ ret = seq_open(file, &show_ftrace_seq_ops);
+ if (!ret) {
+ struct seq_file *m = file->private_data;
+ m->private = iter;
+ } else
+ kfree(iter);
+ } else
+ file->private_data = iter;
+ mutex_unlock(&ftrace_regex_lock);
- list_for_each_entry_safe(p, t, &ftrace_new_addrs, list) {
+ return ret;
+}
- /* If something went wrong, bail without enabling anything */
- if (unlikely(ftrace_disabled))
- return -1;
+static int
+ftrace_filter_open(struct inode *inode, struct file *file)
+{
+ return ftrace_regex_open(inode, file, 1);
+}
- list_del_init(&p->list);
+static int
+ftrace_notrace_open(struct inode *inode, struct file *file)
+{
+ return ftrace_regex_open(inode, file, 0);
+}
- /* convert record (i.e, patch mcount-call with NOP) */
- if (ftrace_code_disable(mod, p)) {
- p->flags |= FTRACE_FL_CONVERTED;
- ftrace_update_cnt++;
- } else
- ftrace_free_rec(p);
- }
+static loff_t
+ftrace_regex_lseek(struct file *file, loff_t offset, int origin)
+{
+ loff_t ret;
- stop = ftrace_now(raw_smp_processor_id());
- ftrace_update_time = stop - start;
- ftrace_update_tot_cnt += ftrace_update_cnt;
+ if (file->f_mode & FMODE_READ)
+ ret = seq_lseek(file, offset, origin);
+ else
+ file->f_pos = ret = 1;
- return 0;
+ return ret;
}
-static int __init ftrace_dyn_table_alloc(unsigned long num_to_init)
+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)
{
- struct ftrace_page *pg;
- int cnt;
+ int type = MATCH_FULL;
int i;
- /* allocate a few pages */
- ftrace_pages_start = (void *)get_zeroed_page(GFP_KERNEL);
- if (!ftrace_pages_start)
- return -1;
-
- /*
- * Allocate a few more pages.
- *
- * TODO: have some parser search vmlinux before
- * final linking to find all calls to ftrace.
- * Then we can:
- * a) know how many pages to allocate.
- * and/or
- * b) set up the table then.
- *
- * The dynamic code is still necessary for
- * modules.
- */
+ if (buff[0] == '!') {
+ *not = 1;
+ buff++;
+ len--;
+ } else
+ *not = 0;
- pg = ftrace_pages = ftrace_pages_start;
+ *search = buff;
- cnt = num_to_init / ENTRIES_PER_PAGE;
- pr_info("ftrace: allocating %ld entries in %d pages\n",
- num_to_init, cnt + 1);
+ 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;
+ }
+ }
+ }
- for (i = 0; i < cnt; i++) {
- pg->next = (void *)get_zeroed_page(GFP_KERNEL);
+ return type;
+}
- /* If we fail, we'll try later anyway */
- if (!pg->next)
- break;
+static int ftrace_match(char *str, char *regex, int len, int type)
+{
+ int matched = 0;
+ char *ptr;
- pg = pg->next;
+ switch (type) {
+ case MATCH_FULL:
+ if (strcmp(str, regex) == 0)
+ matched = 1;
+ break;
+ case MATCH_FRONT_ONLY:
+ if (strncmp(str, regex, len) == 0)
+ matched = 1;
+ break;
+ case MATCH_MIDDLE_ONLY:
+ if (strstr(str, regex))
+ matched = 1;
+ break;
+ case MATCH_END_ONLY:
+ ptr = strstr(str, regex);
+ if (ptr && (ptr[len] == 0))
+ matched = 1;
+ break;
}
- return 0;
+ return matched;
}
-enum {
- FTRACE_ITER_FILTER = (1 << 0),
- FTRACE_ITER_CONT = (1 << 1),
- FTRACE_ITER_NOTRACE = (1 << 2),
- FTRACE_ITER_FAILURES = (1 << 3),
-};
-
-#define FTRACE_BUFF_MAX (KSYM_SYMBOL_LEN+4) /* room for wildcards */
+static int
+ftrace_match_record(struct dyn_ftrace *rec, char *regex, int len, int type)
+{
+ char str[KSYM_SYMBOL_LEN];
-struct ftrace_iterator {
- struct ftrace_page *pg;
- unsigned idx;
- unsigned flags;
- unsigned char buffer[FTRACE_BUFF_MAX+1];
- unsigned buffer_idx;
- unsigned filtered;
-};
+ kallsyms_lookup(rec->ip, NULL, NULL, NULL, str);
+ return ftrace_match(str, regex, len, type);
+}
-static void *
-t_next(struct seq_file *m, void *v, loff_t *pos)
+static void ftrace_match_records(char *buff, int len, int enable)
{
- struct ftrace_iterator *iter = m->private;
- struct dyn_ftrace *rec = NULL;
-
- (*pos)++;
+ unsigned int search_len;
+ struct ftrace_page *pg;
+ struct dyn_ftrace *rec;
+ unsigned long flag;
+ char *search;
+ int type;
+ int not;
- /* should not be called from interrupt context */
- spin_lock(&ftrace_lock);
- retry:
- if (iter->idx >= iter->pg->index) {
- if (iter->pg->next) {
- iter->pg = iter->pg->next;
- iter->idx = 0;
- goto retry;
- } else {
- iter->idx = -1;
- }
- } else {
- rec = &iter->pg->records[iter->idx++];
- if ((rec->flags & FTRACE_FL_FREE) ||
+ flag = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE;
+ type = ftrace_setup_glob(buff, len, &search, ¬);
- (!(iter->flags & FTRACE_ITER_FAILURES) &&
- (rec->flags & FTRACE_FL_FAILED)) ||
+ search_len = strlen(search);
- ((iter->flags & FTRACE_ITER_FAILURES) &&
- !(rec->flags & FTRACE_FL_FAILED)) ||
+ mutex_lock(&ftrace_lock);
+ do_for_each_ftrace_rec(pg, rec) {
- ((iter->flags & FTRACE_ITER_FILTER) &&
- !(rec->flags & FTRACE_FL_FILTER)) ||
+ if (rec->flags & FTRACE_FL_FAILED)
+ continue;
- ((iter->flags & FTRACE_ITER_NOTRACE) &&
- !(rec->flags & FTRACE_FL_NOTRACE))) {
- rec = NULL;
- goto retry;
+ if (ftrace_match_record(rec, search, search_len, type)) {
+ if (not)
+ rec->flags &= ~flag;
+ else
+ rec->flags |= flag;
}
- }
- spin_unlock(&ftrace_lock);
-
- return rec;
+ /*
+ * Only enable filtering if we have a function that
+ * is filtered on.
+ */
+ if (enable && (rec->flags & FTRACE_FL_FILTER))
+ ftrace_filtered = 1;
+ } while_for_each_ftrace_rec();
+ mutex_unlock(&ftrace_lock);
}
-static void *t_start(struct seq_file *m, loff_t *pos)
+static int
+ftrace_match_module_record(struct dyn_ftrace *rec, char *mod,
+ char *regex, int len, int type)
{
- struct ftrace_iterator *iter = m->private;
- void *p = NULL;
+ char str[KSYM_SYMBOL_LEN];
+ char *modname;
- if (*pos > 0) {
- if (iter->idx < 0)
- return p;
- (*pos)--;
- iter->idx--;
- }
+ kallsyms_lookup(rec->ip, NULL, NULL, &modname, str);
- p = t_next(m, p, pos);
+ if (!modname || strcmp(modname, mod))
+ return 0;
- return p;
+ /* blank search means to match all funcs in the mod */
+ if (len)
+ return ftrace_match(str, regex, len, type);
+ else
+ return 1;
}
-static void t_stop(struct seq_file *m, void *p)
+static void ftrace_match_module_records(char *buff, char *mod, int enable)
{
+ unsigned search_len = 0;
+ struct ftrace_page *pg;
+ struct dyn_ftrace *rec;
+ int type = MATCH_FULL;
+ char *search = buff;
+ unsigned long flag;
+ int not = 0;
+
+ flag = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE;
+
+ /* blank or '*' mean the same */
+ if (strcmp(buff, "*") == 0)
+ buff[0] = 0;
+
+ /* handle the case of 'dont filter this module' */
+ if (strcmp(buff, "!") == 0 || strcmp(buff, "!*") == 0) {
+ buff[0] = 0;
+ not = 1;
+ }
+
+ if (strlen(buff)) {
+ type = ftrace_setup_glob(buff, strlen(buff), &search, ¬);
+ search_len = strlen(search);
+ }
+
+ mutex_lock(&ftrace_lock);
+ do_for_each_ftrace_rec(pg, rec) {
+
+ if (rec->flags & FTRACE_FL_FAILED)
+ continue;
+
+ if (ftrace_match_module_record(rec, mod,
+ search, search_len, type)) {
+ if (not)
+ rec->flags &= ~flag;
+ else
+ rec->flags |= flag;
+ }
+ if (enable && (rec->flags & FTRACE_FL_FILTER))
+ ftrace_filtered = 1;
+
+ } while_for_each_ftrace_rec();
+ mutex_unlock(&ftrace_lock);
}
-static int t_show(struct seq_file *m, void *v)
+/*
+ * We register the module command as a template to show others how
+ * to register the a command as well.
+ */
+
+static int
+ftrace_mod_callback(char *func, char *cmd, char *param, int enable)
{
- struct dyn_ftrace *rec = v;
- char str[KSYM_SYMBOL_LEN];
+ char *mod;
- if (!rec)
- return 0;
+ /*
+ * cmd == 'mod' because we only registered this func
+ * for the 'mod' ftrace_func_command.
+ * But if you register one func with multiple commands,
+ * you can tell which command was used by the cmd
+ * parameter.
+ */
- kallsyms_lookup(rec->ip, NULL, NULL, NULL, str);
+ /* we must have a module name */
+ if (!param)
+ return -EINVAL;
- seq_printf(m, "%s\n", str);
+ mod = strsep(¶m, ":");
+ if (!strlen(mod))
+ return -EINVAL;
+ ftrace_match_module_records(func, mod, enable);
return 0;
}
-static struct seq_operations show_ftrace_seq_ops = {
- .start = t_start,
- .next = t_next,
- .stop = t_stop,
- .show = t_show,
+static struct ftrace_func_command ftrace_mod_cmd = {
+ .name = "mod",
+ .func = ftrace_mod_callback,
};
-static int
-ftrace_avail_open(struct inode *inode, struct file *file)
+static int __init ftrace_mod_cmd_init(void)
{
- struct ftrace_iterator *iter;
- int ret;
+ return register_ftrace_command(&ftrace_mod_cmd);
+}
+device_initcall(ftrace_mod_cmd_init);
- if (unlikely(ftrace_disabled))
- return -ENODEV;
+static void
+function_trace_probe_call(unsigned long ip, unsigned long parent_ip)
+{
+ struct ftrace_func_probe *entry;
+ struct hlist_head *hhd;
+ struct hlist_node *n;
+ unsigned long key;
+ int resched;
- iter = kzalloc(sizeof(*iter), GFP_KERNEL);
- if (!iter)
- return -ENOMEM;
+ key = hash_long(ip, FTRACE_HASH_BITS);
- iter->pg = ftrace_pages_start;
+ hhd = &ftrace_func_hash[key];
- ret = seq_open(file, &show_ftrace_seq_ops);
- if (!ret) {
- struct seq_file *m = file->private_data;
+ if (hlist_empty(hhd))
+ return;
- m->private = iter;
- } else {
- kfree(iter);
+ /*
+ * Disable preemption for these calls to prevent a RCU grace
+ * period. This syncs the hash iteration and freeing of items
+ * on the hash. rcu_read_lock is too dangerous here.
+ */
+ resched = ftrace_preempt_disable();
+ hlist_for_each_entry_rcu(entry, n, hhd, node) {
+ if (entry->ip == ip)
+ entry->ops->func(ip, parent_ip, &entry->data);
}
-
- return ret;
+ ftrace_preempt_enable(resched);
}
-int ftrace_avail_release(struct inode *inode, struct file *file)
+static struct ftrace_ops trace_probe_ops __read_mostly =
{
- struct seq_file *m = (struct seq_file *)file->private_data;
- struct ftrace_iterator *iter = m->private;
+ .func = function_trace_probe_call,
+};
- seq_release(inode, file);
- kfree(iter);
+static int ftrace_probe_registered;
- return 0;
+static void __enable_ftrace_function_probe(void)
+{
+ int i;
+
+ if (ftrace_probe_registered)
+ return;
+
+ for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) {
+ struct hlist_head *hhd = &ftrace_func_hash[i];
+ if (hhd->first)
+ break;
+ }
+ /* Nothing registered? */
+ if (i == FTRACE_FUNC_HASHSIZE)
+ return;
+
+ __register_ftrace_function(&trace_probe_ops);
+ ftrace_startup(0);
+ ftrace_probe_registered = 1;
}
-static int
-ftrace_failures_open(struct inode *inode, struct file *file)
+static void __disable_ftrace_function_probe(void)
{
- int ret;
- struct seq_file *m;
- struct ftrace_iterator *iter;
+ int i;
- ret = ftrace_avail_open(inode, file);
- if (!ret) {
- m = (struct seq_file *)file->private_data;
- iter = (struct ftrace_iterator *)m->private;
- iter->flags = FTRACE_ITER_FAILURES;
+ if (!ftrace_probe_registered)
+ return;
+
+ for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) {
+ struct hlist_head *hhd = &ftrace_func_hash[i];
+ if (hhd->first)
+ return;
}
- return ret;
+ /* no more funcs left */
+ __unregister_ftrace_function(&trace_probe_ops);
+ ftrace_shutdown(0);
+ ftrace_probe_registered = 0;
}
-static void ftrace_filter_reset(int enable)
+static void ftrace_free_entry_rcu(struct rcu_head *rhp)
+{
+ struct ftrace_func_probe *entry =
+ container_of(rhp, struct ftrace_func_probe, rcu);
+
+ if (entry->ops->free)
+ entry->ops->free(&entry->data);
+ kfree(entry);
+}
+
+
+int
+register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
+ void *data)
{
+ struct ftrace_func_probe *entry;
struct ftrace_page *pg;
struct dyn_ftrace *rec;
- unsigned long type = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE;
- unsigned i;
+ int type, len, not;
+ unsigned long key;
+ int count = 0;
+ char *search;
- /* should not be called from interrupt context */
- spin_lock(&ftrace_lock);
- if (enable)
- ftrace_filtered = 0;
- pg = ftrace_pages_start;
- while (pg) {
- for (i = 0; i < pg->index; i++) {
- rec = &pg->records[i];
- if (rec->flags & FTRACE_FL_FAILED)
+ type = ftrace_setup_glob(glob, strlen(glob), &search, ¬);
+ len = strlen(search);
+
+ /* we do not support '!' for function probes */
+ if (WARN_ON(not))
+ return -EINVAL;
+
+ mutex_lock(&ftrace_lock);
+ do_for_each_ftrace_rec(pg, rec) {
+
+ if (rec->flags & FTRACE_FL_FAILED)
+ continue;
+
+ if (!ftrace_match_record(rec, search, len, type))
+ continue;
+
+ entry = kmalloc(sizeof(*entry), GFP_KERNEL);
+ if (!entry) {
+ /* If we did not process any, then return error */
+ if (!count)
+ count = -ENOMEM;
+ goto out_unlock;
+ }
+
+ count++;
+
+ entry->data = data;
+
+ /*
+ * The caller might want to do something special
+ * for each function we find. We call the callback
+ * to give the caller an opportunity to do so.
+ */
+ if (ops->callback) {
+ if (ops->callback(rec->ip, &entry->data) < 0) {
+ /* caller does not like this func */
+ kfree(entry);
continue;
- rec->flags &= ~type;
+ }
}
- pg = pg->next;
- }
- spin_unlock(&ftrace_lock);
+
+ entry->ops = ops;
+ entry->ip = rec->ip;
+
+ key = hash_long(entry->ip, FTRACE_HASH_BITS);
+ hlist_add_head_rcu(&entry->node, &ftrace_func_hash[key]);
+
+ } while_for_each_ftrace_rec();
+ __enable_ftrace_function_probe();
+
+ out_unlock:
+ mutex_unlock(&ftrace_lock);
+
+ return count;
}
-static int
-ftrace_regex_open(struct inode *inode, struct file *file, int enable)
+enum {
+ PROBE_TEST_FUNC = 1,
+ PROBE_TEST_DATA = 2
+};
+
+static void
+__unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
+ void *data, int flags)
{
- struct ftrace_iterator *iter;
- int ret = 0;
+ struct ftrace_func_probe *entry;
+ struct hlist_node *n, *tmp;
+ char str[KSYM_SYMBOL_LEN];
+ int type = MATCH_FULL;
+ int i, len = 0;
+ char *search;
- if (unlikely(ftrace_disabled))
- return -ENODEV;
+ if (glob && (strcmp(glob, "*") == 0 || !strlen(glob)))
+ glob = NULL;
+ else if (glob) {
+ int not;
- iter = kzalloc(sizeof(*iter), GFP_KERNEL);
- if (!iter)
- return -ENOMEM;
+ type = ftrace_setup_glob(glob, strlen(glob), &search, ¬);
+ len = strlen(search);
- mutex_lock(&ftrace_regex_lock);
- if ((file->f_mode & FMODE_WRITE) &&
- !(file->f_flags & O_APPEND))
- ftrace_filter_reset(enable);
+ /* we do not support '!' for function probes */
+ if (WARN_ON(not))
+ return;
+ }
- if (file->f_mode & FMODE_READ) {
- iter->pg = ftrace_pages_start;
- iter->flags = enable ? FTRACE_ITER_FILTER :
- FTRACE_ITER_NOTRACE;
+ mutex_lock(&ftrace_lock);
+ for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) {
+ struct hlist_head *hhd = &ftrace_func_hash[i];
- ret = seq_open(file, &show_ftrace_seq_ops);
- if (!ret) {
- struct seq_file *m = file->private_data;
- m->private = iter;
- } else
- kfree(iter);
- } else
- file->private_data = iter;
- mutex_unlock(&ftrace_regex_lock);
+ hlist_for_each_entry_safe(entry, n, tmp, hhd, node) {
- return ret;
+ /* break up if statements for readability */
+ if ((flags & PROBE_TEST_FUNC) && entry->ops != ops)
+ continue;
+
+ if ((flags & PROBE_TEST_DATA) && entry->data != data)
+ continue;
+
+ /* do this last, since it is the most expensive */
+ if (glob) {
+ kallsyms_lookup(entry->ip, NULL, NULL,
+ NULL, str);
+ if (!ftrace_match(str, glob, len, type))
+ continue;
+ }
+
+ hlist_del(&entry->node);
+ call_rcu(&entry->rcu, ftrace_free_entry_rcu);
+ }
+ }
+ __disable_ftrace_function_probe();
+ mutex_unlock(&ftrace_lock);
}
-static int
-ftrace_filter_open(struct inode *inode, struct file *file)
+void
+unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
+ void *data)
{
- return ftrace_regex_open(inode, file, 1);
+ __unregister_ftrace_function_probe(glob, ops, data,
+ PROBE_TEST_FUNC | PROBE_TEST_DATA);
}
-static int
-ftrace_notrace_open(struct inode *inode, struct file *file)
+void
+unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops)
{
- return ftrace_regex_open(inode, file, 0);
+ __unregister_ftrace_function_probe(glob, ops, NULL, PROBE_TEST_FUNC);
+}
+
+void unregister_ftrace_function_probe_all(char *glob)
+{
+ __unregister_ftrace_function_probe(glob, NULL, NULL, 0);
}
-static ssize_t
-ftrace_regex_read(struct file *file, char __user *ubuf,
- size_t cnt, loff_t *ppos)
-{
- if (file->f_mode & FMODE_READ)
- return seq_read(file, ubuf, cnt, ppos);
- else
- return -EPERM;
+static LIST_HEAD(ftrace_commands);
+static DEFINE_MUTEX(ftrace_cmd_mutex);
+
+int register_ftrace_command(struct ftrace_func_command *cmd)
+{
+ struct ftrace_func_command *p;
+ int ret = 0;
+
+ mutex_lock(&ftrace_cmd_mutex);
+ list_for_each_entry(p, &ftrace_commands, list) {
+ if (strcmp(cmd->name, p->name) == 0) {
+ ret = -EBUSY;
+ goto out_unlock;
+ }
+ }
+ list_add(&cmd->list, &ftrace_commands);
+ out_unlock:
+ mutex_unlock(&ftrace_cmd_mutex);
+
+ return ret;
}
-static loff_t
-ftrace_regex_lseek(struct file *file, loff_t offset, int origin)
+int unregister_ftrace_command(struct ftrace_func_command *cmd)
{
- loff_t ret;
+ struct ftrace_func_command *p, *n;
+ int ret = -ENODEV;
- if (file->f_mode & FMODE_READ)
- ret = seq_lseek(file, offset, origin);
- else
- file->f_pos = ret = 1;
+ mutex_lock(&ftrace_cmd_mutex);
+ list_for_each_entry_safe(p, n, &ftrace_commands, list) {
+ if (strcmp(cmd->name, p->name) == 0) {
+ ret = 0;
+ list_del_init(&p->list);
+ goto out_unlock;
+ }
+ }
+ out_unlock:
+ mutex_unlock(&ftrace_cmd_mutex);
return ret;
}
-enum {
- MATCH_FULL,
- MATCH_FRONT_ONLY,
- MATCH_MIDDLE_ONLY,
- MATCH_END_ONLY,
-};
-
-static void
-ftrace_match(unsigned char *buff, int len, int enable)
+static int ftrace_process_regex(char *buff, int len, int enable)
{
- char str[KSYM_SYMBOL_LEN];
- char *search = NULL;
- struct ftrace_page *pg;
- struct dyn_ftrace *rec;
- int type = MATCH_FULL;
- unsigned long flag = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE;
- unsigned i, match = 0, search_len = 0;
+ char *func, *command, *next = buff;
+ struct ftrace_func_command *p;
+ int ret = -EINVAL;
- for (i = 0; i < len; i++) {
- if (buff[i] == '*') {
- if (!i) {
- search = buff + i + 1;
- type = MATCH_END_ONLY;
- search_len = len - (i + 1);
- } else {
- if (type == MATCH_END_ONLY) {
- type = MATCH_MIDDLE_ONLY;
- } else {
- match = i;
- type = MATCH_FRONT_ONLY;
- }
- buff[i] = 0;
- break;
- }
- }
+ func = strsep(&next, ":");
+
+ if (!next) {
+ ftrace_match_records(func, len, enable);
+ return 0;
}
- /* should not be called from interrupt context */
- spin_lock(&ftrace_lock);
- if (enable)
- ftrace_filtered = 1;
- pg = ftrace_pages_start;
- while (pg) {
- for (i = 0; i < pg->index; i++) {
- int matched = 0;
- char *ptr;
+ /* command found */
- rec = &pg->records[i];
- if (rec->flags & FTRACE_FL_FAILED)
- continue;
- kallsyms_lookup(rec->ip, NULL, NULL, NULL, str);
- switch (type) {
- case MATCH_FULL:
- if (strcmp(str, buff) == 0)
- matched = 1;
- break;
- case MATCH_FRONT_ONLY:
- if (memcmp(str, buff, match) == 0)
- matched = 1;
- break;
- case MATCH_MIDDLE_ONLY:
- if (strstr(str, search))
- matched = 1;
- break;
- case MATCH_END_ONLY:
- ptr = strstr(str, search);
- if (ptr && (ptr[search_len] == 0))
- matched = 1;
- break;
- }
- if (matched)
- rec->flags |= flag;
+ command = strsep(&next, ":");
+
+ mutex_lock(&ftrace_cmd_mutex);
+ list_for_each_entry(p, &ftrace_commands, list) {
+ if (strcmp(p->name, command) == 0) {
+ ret = p->func(func, command, next, enable);
+ goto out_unlock;
}
- pg = pg->next;
}
- spin_unlock(&ftrace_lock);
+ out_unlock:
+ mutex_unlock(&ftrace_cmd_mutex);
+
+ return ret;
}
static ssize_t
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)
return 0;
} 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 (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;
- ftrace_match(iter->buffer, iter->buffer_idx, enable);
- 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;
}
if (reset)
ftrace_filter_reset(enable);
if (buf)
- ftrace_match(buf, len, enable);
+ ftrace_match_records(buf, len, enable);
mutex_unlock(&ftrace_regex_lock);
}
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 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);
+
+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);
+}
+
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(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_sysctl_lock);
- mutex_lock(&ftrace_start_lock);
+ mutex_lock(&ftrace_lock);
if (ftrace_start_up && ftrace_enabled)
ftrace_run_update_code(FTRACE_ENABLE_CALLS);
- mutex_unlock(&ftrace_start_lock);
- mutex_unlock(&ftrace_sysctl_lock);
+ mutex_unlock(&ftrace_lock);
+ trace_parser_put(parser);
kfree(iter);
+
mutex_unlock(&ftrace_regex_lock);
return 0;
}
return ftrace_regex_release(inode, file, 0);
}
-static struct file_operations ftrace_avail_fops = {
+static const struct file_operations ftrace_avail_fops = {
.open = ftrace_avail_open,
.read = seq_read,
.llseek = seq_lseek,
- .release = ftrace_avail_release,
+ .release = seq_release_private,
};
-static struct file_operations ftrace_failures_fops = {
+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 struct file_operations ftrace_filter_fops = {
+static const struct file_operations ftrace_filter_fops = {
.open = ftrace_filter_open,
- .read = ftrace_regex_read,
+ .read = seq_read,
.write = ftrace_filter_write,
.llseek = ftrace_regex_lseek,
.release = ftrace_filter_release,
};
-static struct file_operations ftrace_notrace_fops = {
+static const struct file_operations ftrace_notrace_fops = {
.open = ftrace_notrace_open,
- .read = ftrace_regex_read,
+ .read = seq_read,
.write = ftrace_notrace_write,
.llseek = ftrace_regex_lseek,
.release = ftrace_notrace_release,
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);
- p = g_next(m, p, pos);
+ /* Nothing, tell g_show to print all functions are enabled */
+ if (!ftrace_graph_count && !*pos)
+ return (void *)1;
- 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;
- kallsyms_lookup(*ptr, NULL, NULL, NULL, str);
+ if (ptr == (unsigned long *)1) {
+ seq_printf(m, "#### all functions enabled ####\n");
+ return 0;
+ }
- 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 ssize_t
-ftrace_graph_read(struct file *file, char __user *ubuf,
- size_t cnt, loff_t *ppos)
+static int
+ftrace_graph_release(struct inode *inode, struct file *file)
{
if (file->f_mode & FMODE_READ)
- return seq_read(file, ubuf, cnt, ppos);
- else
- return -EPERM;
+ seq_release(inode, file);
+ return 0;
}
static int
-ftrace_set_func(unsigned long *array, int idx, char *buffer)
+ftrace_set_func(unsigned long *array, int *idx, char *buffer)
{
- char str[KSYM_SYMBOL_LEN];
struct dyn_ftrace *rec;
struct ftrace_page *pg;
+ int search_len;
int found = 0;
- int i, j;
+ int type, not;
+ char *search;
+ bool exists;
+ int i;
if (ftrace_disabled)
return -ENODEV;
- /* should not be called from interrupt context */
- spin_lock(&ftrace_lock);
+ /* decode regex */
+ type = ftrace_setup_glob(buffer, strlen(buffer), &search, ¬);
+ if (not)
+ return -EINVAL;
- for (pg = ftrace_pages_start; pg; pg = pg->next) {
- for (i = 0; i < pg->index; i++) {
- rec = &pg->records[i];
+ search_len = strlen(search);
- if (rec->flags & (FTRACE_FL_FAILED | FTRACE_FL_FREE))
- continue;
+ mutex_lock(&ftrace_lock);
+ do_for_each_ftrace_rec(pg, rec) {
+
+ if (*idx >= FTRACE_GRAPH_MAX_FUNCS)
+ break;
- kallsyms_lookup(rec->ip, NULL, NULL, NULL, str);
- if (strcmp(str, buffer) == 0) {
+ if (rec->flags & (FTRACE_FL_FAILED | FTRACE_FL_FREE))
+ continue;
+
+ if (ftrace_match_record(rec, search, search_len, type)) {
+ /* ensure it is not already in the array */
+ exists = false;
+ for (i = 0; i < *idx; i++)
+ if (array[i] == rec->ip) {
+ exists = true;
+ break;
+ }
+ if (!exists) {
+ array[(*idx)++] = rec->ip;
found = 1;
- for (j = 0; j < idx; j++)
- if (array[j] == rec->ip) {
- found = 0;
- break;
- }
- if (found)
- array[idx] = rec->ip;
- break;
}
}
- }
- spin_unlock(&ftrace_lock);
+ } while_for_each_ftrace_rec();
+
+ mutex_unlock(&ftrace_lock);
return found ? 0 : -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;
+ struct trace_parser parser;
size_t read = 0;
ssize_t ret;
- int index = 0;
- char ch;
if (!cnt || cnt < 0)
return 0;
goto out;
}
- 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)
+ if (trace_parser_get_init(&parser, FTRACE_BUFF_MAX)) {
+ ret = -ENOMEM;
goto out;
- read++;
- cnt--;
-
- /* skip white space */
- while (cnt && isspace(ch)) {
- ret = get_user(ch, ubuf++);
- if (ret)
- goto out;
- read++;
- cnt--;
}
- 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 (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--;
}
- buffer[index] = 0;
-
- /* we allow only one at a time */
- ret = ftrace_set_func(array, ftrace_graph_count, buffer);
- if (ret)
- goto out;
-
- ftrace_graph_count++;
-
- file->f_pos += read;
ret = read;
out:
+ trace_parser_put(&parser);
mutex_unlock(&graph_lock);
return ret;
}
static const struct file_operations ftrace_graph_fops = {
- .open = ftrace_graph_open,
- .read = ftrace_graph_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;
unsigned long addr;
unsigned long flags;
- mutex_lock(&ftrace_start_lock);
+ mutex_lock(&ftrace_lock);
p = start;
while (p < end) {
addr = ftrace_call_adjust(*p++);
local_irq_save(flags);
ftrace_update_code(mod);
local_irq_restore(flags);
- mutex_unlock(&ftrace_start_lock);
+ mutex_unlock(&ftrace_lock);
return 0;
}
-void ftrace_init_module(struct module *mod,
- unsigned long *start, unsigned long *end)
+#ifdef CONFIG_MODULES
+void ftrace_release(void *start, void *end)
+{
+ struct dyn_ftrace *rec;
+ struct ftrace_page *pg;
+ unsigned long s = (unsigned long)start;
+ unsigned long e = (unsigned long)end;
+
+ if (ftrace_disabled || !start || start == end)
+ return;
+
+ mutex_lock(&ftrace_lock);
+ do_for_each_ftrace_rec(pg, rec) {
+ if ((rec->ip >= s) && (rec->ip < e)) {
+ /*
+ * 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);
}
+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->ftrace_callsites,
+ mod->ftrace_callsites +
+ mod->num_ftrace_callsites);
+ 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[];
__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;
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));
+ r = sprintf(buf, "%u\n", pid_vnr(ftrace_pid_trace));
else
r = sprintf(buf, "no pid\n");
{
struct task_struct *p;
+ rcu_read_lock();
do_each_pid_task(pid, PIDTYPE_PID, p) {
clear_tsk_trace_trace(p);
} while_each_pid_task(pid, PIDTYPE_PID, p);
+ rcu_read_unlock();
+
put_pid(pid);
}
{
struct task_struct *p;
+ rcu_read_lock();
do_each_pid_task(pid, PIDTYPE_PID, p) {
set_tsk_trace_trace(p);
} while_each_pid_task(pid, PIDTYPE_PID, p);
+ rcu_read_unlock();
}
static void clear_ftrace_pid_task(struct pid **pid)
if (ret < 0)
return ret;
- mutex_lock(&ftrace_start_lock);
+ mutex_lock(&ftrace_lock);
if (val < 0) {
/* disable pid tracing */
if (!ftrace_pid_trace)
ftrace_startup_enable(0);
out:
- mutex_unlock(&ftrace_start_lock);
+ mutex_unlock(&ftrace_lock);
return cnt;
}
-static struct file_operations ftrace_pid_fops = {
+static const struct file_operations ftrace_pid_fops = {
.read = ftrace_pid_read,
.write = ftrace_pid_write,
};
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);
/**
if (unlikely(ftrace_disabled))
return -1;
- mutex_lock(&ftrace_sysctl_lock);
+ mutex_lock(&ftrace_lock);
ret = __register_ftrace_function(ops);
ftrace_startup(0);
- mutex_unlock(&ftrace_sysctl_lock);
+ mutex_unlock(&ftrace_lock);
return ret;
}
/**
- * unregister_ftrace_function - unresgister a function for profiling.
+ * unregister_ftrace_function - unregister a function for profiling.
* @ops - ops structure that holds the function to unregister
*
* Unregister a function that was added to be called by ftrace profiling.
{
int ret;
- mutex_lock(&ftrace_sysctl_lock);
+ mutex_lock(&ftrace_lock);
ret = __unregister_ftrace_function(ops);
ftrace_shutdown(0);
- mutex_unlock(&ftrace_sysctl_lock);
+ mutex_unlock(&ftrace_lock);
return ret;
}
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;
if (unlikely(ftrace_disabled))
return -ENODEV;
- mutex_lock(&ftrace_sysctl_lock);
+ 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) {
}
out:
- mutex_unlock(&ftrace_sysctl_lock);
+ mutex_unlock(&ftrace_lock);
return ret;
}
#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) {
+ atomic_set(&t->tracing_graph_pause, 0);
+ atomic_set(&t->trace_overrun, 0);
t->curr_ret_stack = -1;
- /* Make sure IRQs see the -1 first: */
- barrier();
+ /* Make sure the tasks see the -1 first: */
+ smp_wmb();
t->ret_stack = ret_stack_list[start++];
- atomic_set(&t->trace_overrun, 0);
}
} 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)
{
struct ftrace_ret_stack **ret_stack_list;
- int ret;
+ int ret, cpu;
ret_stack_list = kmalloc(FTRACE_RETSTACK_ALLOC_SIZE *
sizeof(struct ftrace_ret_stack *),
if (!ret_stack_list)
return -ENOMEM;
+ /* The cpu_boot init_task->ret_stack will never be freed */
+ 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;
}
+/*
+ * Hibernation protection.
+ * The state of the current task is too much unstable during
+ * suspend/restore to disk. We want to protect against that.
+ */
+static int
+ftrace_suspend_notifier_call(struct notifier_block *bl, unsigned long state,
+ void *unused)
+{
+ switch (state) {
+ case PM_HIBERNATION_PREPARE:
+ pause_graph_tracing();
+ break;
+
+ case PM_POST_HIBERNATION:
+ unpause_graph_tracing();
+ break;
+ }
+ return NOTIFY_DONE;
+}
+
int register_ftrace_graph(trace_func_graph_ret_t retfunc,
trace_func_graph_ent_t entryfunc)
{
int ret = 0;
- mutex_lock(&ftrace_sysctl_lock);
+ 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;
}
ftrace_startup(FTRACE_START_FUNC_RET);
out:
- mutex_unlock(&ftrace_sysctl_lock);
+ mutex_unlock(&ftrace_lock);
return ret;
}
void unregister_ftrace_graph(void)
{
- mutex_lock(&ftrace_sysctl_lock);
+ 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);
- mutex_unlock(&ftrace_sysctl_lock);
+ 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