1 files changed, 78 insertions, 110 deletions

diff --git a/kernel/trace/trace_ksym.c b/kernel/trace/trace_ksym.c
index acb87d4a4ac1..94103cdcf9d8 100644
--- a/kernel/trace/trace_ksym.c
+++ b/kernel/trace/trace_ksym.c
@@ -26,12 +26,13 @@
 #include <linux/fs.h>
 
 #include "trace_output.h"
-#include "trace_stat.h"
 #include "trace.h"
 
 #include <linux/hw_breakpoint.h>
 #include <asm/hw_breakpoint.h>
 
+#include <asm/atomic.h>
+
 /*
  * For now, let us restrict the no. of symbols traced simultaneously to number
  * of available hardware breakpoint registers.
@@ -44,7 +45,7 @@ struct trace_ksym {
         struct perf_event       **ksym_hbp;
         struct perf_event_attr  attr;
 #ifdef CONFIG_PROFILE_KSYM_TRACER
-        unsigned long           counter;
+        atomic64_t              counter;
 #endif
         struct hlist_node       ksym_hlist;
 };
@@ -69,9 +70,8 @@ void ksym_collect_stats(unsigned long hbp_hit_addr)
 
         rcu_read_lock();
         hlist_for_each_entry_rcu(entry, node, &ksym_filter_head, ksym_hlist) {
-                if ((entry->attr.bp_addr == hbp_hit_addr) &&
-                    (entry->counter <= MAX_UL_INT)) {
-                        entry->counter++;
+                if (entry->attr.bp_addr == hbp_hit_addr) {
+                        atomic64_inc(&entry->counter);
                         break;
                 }
         }
@@ -197,7 +197,6 @@ int process_new_ksym_entry(char *ksymname, int op, unsigned long addr)
         entry->attr.bp_addr = addr;
         entry->attr.bp_len = HW_BREAKPOINT_LEN_4;
 
-        ret = -EAGAIN;
         entry->ksym_hbp = register_wide_hw_breakpoint(&entry->attr,
                                         ksym_hbp_handler);
 
@@ -236,7 +235,8 @@ static ssize_t ksym_trace_filter_read(struct file *filp, char __user *ubuf,
         mutex_lock(&ksym_tracer_mutex);
 
         hlist_for_each_entry(entry, node, &ksym_filter_head, ksym_hlist) {
-                ret = trace_seq_printf(s, "%pS:", (void *)entry->attr.bp_addr);
+                ret = trace_seq_printf(s, "%pS:",
+                                (void *)(unsigned long)entry->attr.bp_addr);
                 if (entry->attr.bp_type == HW_BREAKPOINT_R)
                         ret = trace_seq_puts(s, "r--\n");
                 else if (entry->attr.bp_type == HW_BREAKPOINT_W)
@@ -278,21 +278,20 @@ static ssize_t ksym_trace_filter_write(struct file *file,
 {
         struct trace_ksym *entry;
         struct hlist_node *node;
-        char *input_string, *ksymname = NULL;
+        char *buf, *input_string, *ksymname = NULL;
         unsigned long ksym_addr = 0;
         int ret, op, changed = 0;
 
-        input_string = kzalloc(count + 1, GFP_KERNEL);
-        if (!input_string)
+        buf = kzalloc(count + 1, GFP_KERNEL);
+        if (!buf)
                 return -ENOMEM;
 
-        if (copy_from_user(input_string, buffer, count)) {
-                kfree(input_string);
-                return -EFAULT;
-        }
-        input_string[count] = '\0';
+        ret = -EFAULT;
+        if (copy_from_user(buf, buffer, count))
+                goto out;
 
-        strstrip(input_string);
+        buf[count] = '\0';
+        input_string = strstrip(buf);
 
         /*
          * Clear all breakpoints if:
@@ -303,15 +302,13 @@ static ssize_t ksym_trace_filter_write(struct file *file,
         if (!input_string[0] || !strcmp(input_string, "0") ||
             !strcmp(input_string, "*:---")) {
                 __ksym_trace_reset();
-                kfree(input_string);
-                return count;
+                ret = 0;
+                goto out;
         }
 
         ret = op = parse_ksym_trace_str(input_string, &ksymname, &ksym_addr);
-        if (ret < 0) {
-                kfree(input_string);
-                return ret;
-        }
+        if (ret < 0)
+                goto out;
 
         mutex_lock(&ksym_tracer_mutex);
 
@@ -322,7 +319,7 @@ static ssize_t ksym_trace_filter_write(struct file *file,
                         if (entry->attr.bp_type != op)
                                 changed = 1;
                         else
-                                goto out;
+                                goto out_unlock;
                         break;
                 }
         }
@@ -337,28 +334,24 @@ static ssize_t ksym_trace_filter_write(struct file *file,
                         if (IS_ERR(entry->ksym_hbp))
                                 ret = PTR_ERR(entry->ksym_hbp);
                         else
-                                goto out;
+                                goto out_unlock;
                 }
                 /* Error or "symbol:---" case: drop it */
                 ksym_filter_entry_count--;
                 hlist_del_rcu(&(entry->ksym_hlist));
                 synchronize_rcu();
                 kfree(entry);
-                goto out;
+                goto out_unlock;
         } else {
                 /* Check for malformed request: (4) */
-                if (op == 0)
-                        goto out;
-                ret = process_new_ksym_entry(ksymname, op, ksym_addr);
+                if (op)
+                        ret = process_new_ksym_entry(ksymname, op, ksym_addr);
         }
-out:
+out_unlock:
         mutex_unlock(&ksym_tracer_mutex);
-
-        kfree(input_string);
-
-        if (!ret)
-                ret = count;
-        return ret;
+out:
+        kfree(buf);
+        return !ret ? count : ret;
 }
 
 static const struct file_operations ksym_tracing_fops = {
@@ -450,102 +443,77 @@ struct tracer ksym_tracer __read_mostly =
         .print_line     = ksym_trace_output
 };
 
-__init static int init_ksym_trace(void)
-{
-        struct dentry *d_tracer;
-        struct dentry *entry;
-
-        d_tracer = tracing_init_dentry();
-        ksym_filter_entry_count = 0;
-
-        entry = debugfs_create_file("ksym_trace_filter", 0644, d_tracer,
-                                    NULL, &ksym_tracing_fops);
-        if (!entry)
-                pr_warning("Could not create debugfs "
-                           "'ksym_trace_filter' file\n");
-
-        return register_tracer(&ksym_tracer);
-}
-device_initcall(init_ksym_trace);
-
-
 #ifdef CONFIG_PROFILE_KSYM_TRACER
-static int ksym_tracer_stat_headers(struct seq_file *m)
+static int ksym_profile_show(struct seq_file *m, void *v)
 {
+        struct hlist_node *node;
+        struct trace_ksym *entry;
+        int access_type = 0;
+        char fn_name[KSYM_NAME_LEN];
+
         seq_puts(m, "  Access Type ");
         seq_puts(m, "  Symbol                                       Counter\n");
         seq_puts(m, "  ----------- ");
         seq_puts(m, "  ------                                       -------\n");
-        return 0;
-}
 
-static int ksym_tracer_stat_show(struct seq_file *m, void *v)
-{
-        struct hlist_node *stat = v;
-        struct trace_ksym *entry;
-        int access_type = 0;
-        char fn_name[KSYM_NAME_LEN];
+        rcu_read_lock();
+        hlist_for_each_entry_rcu(entry, node, &ksym_filter_head, ksym_hlist) {
 
-        entry = hlist_entry(stat, struct trace_ksym, ksym_hlist);
+                access_type = entry->attr.bp_type;
 
-        access_type = entry->attr.bp_type;
+                switch (access_type) {
+                case HW_BREAKPOINT_R:
+                        seq_puts(m, "  R           ");
+                        break;
+                case HW_BREAKPOINT_W:
+                        seq_puts(m, "  W           ");
+                        break;
+                case HW_BREAKPOINT_R | HW_BREAKPOINT_W:
+                        seq_puts(m, "  RW          ");
+                        break;
+                default:
+                        seq_puts(m, "  NA          ");
+                }
 
-        switch (access_type) {
-        case HW_BREAKPOINT_R:
-                seq_puts(m, "  R           ");
-                break;
-        case HW_BREAKPOINT_W:
-                seq_puts(m, "  W           ");
-                break;
-        case HW_BREAKPOINT_R | HW_BREAKPOINT_W:
-                seq_puts(m, "  RW          ");
-                break;
-        default:
-                seq_puts(m, "  NA          ");
+                if (lookup_symbol_name(entry->attr.bp_addr, fn_name) >= 0)
+                        seq_printf(m, "  %-36s", fn_name);
+                else
+                        seq_printf(m, "  %-36s", "<NA>");
+                seq_printf(m, " %15llu\n",
+                           (unsigned long long)atomic64_read(&entry->counter));
         }
-
-        if (lookup_symbol_name(entry->attr.bp_addr, fn_name) >= 0)
-                seq_printf(m, "  %-36s", fn_name);
-        else
-                seq_printf(m, "  %-36s", "<NA>");
-        seq_printf(m, " %15lu\n", entry->counter);
+        rcu_read_unlock();
 
         return 0;
 }
 
-static void *ksym_tracer_stat_start(struct tracer_stat *trace)
+static int ksym_profile_open(struct inode *node, struct file *file)
 {
-        return ksym_filter_head.first;
+        return single_open(file, ksym_profile_show, NULL);
 }
 
-static void *
-ksym_tracer_stat_next(void *v, int idx)
-{
-        struct hlist_node *stat = v;
-
-        return stat->next;
-}
-
-static struct tracer_stat ksym_tracer_stats = {
-        .name = "ksym_tracer",
-        .stat_start = ksym_tracer_stat_start,
-        .stat_next = ksym_tracer_stat_next,
-        .stat_headers = ksym_tracer_stat_headers,
-        .stat_show = ksym_tracer_stat_show
+static const struct file_operations ksym_profile_fops = {
+        .open           = ksym_profile_open,
+        .read           = seq_read,
+        .llseek         = seq_lseek,
+        .release        = single_release,
 };
+#endif /* CONFIG_PROFILE_KSYM_TRACER */
 
-__init static int ksym_tracer_stat_init(void)
+__init static int init_ksym_trace(void)
 {
-        int ret;
+        struct dentry *d_tracer;
 
-        ret = register_stat_tracer(&ksym_tracer_stats);
-        if (ret) {
-                printk(KERN_WARNING "Warning: could not register "
-                                    "ksym tracer stats\n");
-                return 1;
-        }
+        d_tracer = tracing_init_dentry();
 
-        return 0;
+        trace_create_file("ksym_trace_filter", 0644, d_tracer,
+                          NULL, &ksym_tracing_fops);
+
+#ifdef CONFIG_PROFILE_KSYM_TRACER
+        trace_create_file("ksym_profile", 0444, d_tracer,
+                          NULL, &ksym_profile_fops);
+#endif
+
+        return register_tracer(&ksym_tracer);
 }
-fs_initcall(ksym_tracer_stat_init);
-#endif /* CONFIG_PROFILE_KSYM_TRACER */
+device_initcall(init_ksym_trace);