jbd2: convert instrumentation from markers to tracepoints

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

5 files changed, 252 insertions, 9 deletions

diff --git a/fs/jbd2/checkpoint.c b/fs/jbd2/checkpoint.c
index 17159cacbd9e..5d70b3e6d49b 100644
--- a/fs/jbd2/checkpoint.c
+++ b/fs/jbd2/checkpoint.c
@@ -20,9 +20,9 @@
 #include <linux/time.h>
 #include <linux/fs.h>
 #include <linux/jbd2.h>
-#include <linux/marker.h>
 #include <linux/errno.h>
 #include <linux/slab.h>
+#include <trace/events/jbd2.h>
 
 /*
  * Unlink a buffer from a transaction checkpoint list.
@@ -358,8 +358,7 @@ int jbd2_log_do_checkpoint(journal_t *journal)
          * journal straight away.
          */
         result = jbd2_cleanup_journal_tail(journal);
-        trace_mark(jbd2_checkpoint, "dev %s need_checkpoint %d",
-                   journal->j_devname, result);
+        trace_jbd2_checkpoint(journal, result);
         jbd_debug(1, "cleanup_journal_tail returned %d\n", result);
         if (result <= 0)
                 return result;
diff --git a/fs/jbd2/commit.c b/fs/jbd2/commit.c
index 0b7d3b8226fd..7b4088b2364d 100644
--- a/fs/jbd2/commit.c
+++ b/fs/jbd2/commit.c
@@ -16,7 +16,6 @@
 #include <linux/time.h>
 #include <linux/fs.h>
 #include <linux/jbd2.h>
-#include <linux/marker.h>
 #include <linux/errno.h>
 #include <linux/slab.h>
 #include <linux/mm.h>
@@ -26,6 +25,7 @@
 #include <linux/writeback.h>
 #include <linux/backing-dev.h>
 #include <linux/bio.h>
+#include <trace/events/jbd2.h>
 
 /*
  * Default IO end handler for temporary BJ_IO buffer_heads.
@@ -253,6 +253,7 @@ static int journal_submit_data_buffers(journal_t *journal,
                  * block allocation  with delalloc. We need to write
                  * only allocated blocks here.
                  */
+                trace_jbd2_submit_inode_data(jinode->i_vfs_inode);
                 err = journal_submit_inode_data_buffers(mapping);
                 if (!ret)
                         ret = err;
@@ -394,8 +395,7 @@ void jbd2_journal_commit_transaction(journal_t *journal)
         commit_transaction = journal->j_running_transaction;
         J_ASSERT(commit_transaction->t_state == T_RUNNING);
 
-        trace_mark(jbd2_start_commit, "dev %s transaction %d",
-                   journal->j_devname, commit_transaction->t_tid);
+        trace_jbd2_start_commit(journal, commit_transaction);
         jbd_debug(1, "JBD: starting commit of transaction %d\n",
                         commit_transaction->t_tid);
 
@@ -409,6 +409,7 @@ void jbd2_journal_commit_transaction(journal_t *journal)
          */
         if (commit_transaction->t_synchronous_commit)
                 write_op = WRITE_SYNC_PLUG;
+        trace_jbd2_commit_locking(journal, commit_transaction);
         stats.u.run.rs_wait = commit_transaction->t_max_wait;
         stats.u.run.rs_locked = jiffies;
         stats.u.run.rs_running = jbd2_time_diff(commit_transaction->t_start,
@@ -484,6 +485,7 @@ void jbd2_journal_commit_transaction(journal_t *journal)
          */
         jbd2_journal_switch_revoke_table(journal);
 
+        trace_jbd2_commit_flushing(journal, commit_transaction);
         stats.u.run.rs_flushing = jiffies;
         stats.u.run.rs_locked = jbd2_time_diff(stats.u.run.rs_locked,
                                                stats.u.run.rs_flushing);
@@ -520,6 +522,7 @@ void jbd2_journal_commit_transaction(journal_t *journal)
         commit_transaction->t_state = T_COMMIT;
         spin_unlock(&journal->j_state_lock);
 
+        trace_jbd2_commit_logging(journal, commit_transaction);
         stats.u.run.rs_logging = jiffies;
         stats.u.run.rs_flushing = jbd2_time_diff(stats.u.run.rs_flushing,
                                                  stats.u.run.rs_logging);
@@ -1054,9 +1057,7 @@ restart_loop:
         if (journal->j_commit_callback)
                 journal->j_commit_callback(journal, commit_transaction);
 
-        trace_mark(jbd2_end_commit, "dev %s transaction %d head %d",
-                   journal->j_devname, commit_transaction->t_tid,
-                   journal->j_tail_sequence);
+        trace_jbd2_end_commit(journal, commit_transaction);
         jbd_debug(1, "JBD: commit %d complete, head %d\n",
                   journal->j_commit_sequence, journal->j_tail_sequence);
         if (to_free)
diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c
index 62be7d294ec2..18bfd5dab642 100644
--- a/fs/jbd2/journal.c
+++ b/fs/jbd2/journal.c
@@ -38,6 +38,10 @@
 #include <linux/debugfs.h>
 #include <linux/seq_file.h>
 #include <linux/math64.h>
+#include <linux/hash.h>
+
+#define CREATE_TRACE_POINTS
+#include <trace/events/jbd2.h>
 
 #include <asm/uaccess.h>
 #include <asm/page.h>
@@ -2377,6 +2381,71 @@ static void __exit journal_exit(void)
         jbd2_journal_destroy_caches();
 }
 
+/* 
+ * jbd2_dev_to_name is a utility function used by the jbd2 and ext4 
+ * tracing infrastructure to map a dev_t to a device name.
+ *
+ * The caller should use rcu_read_lock() in order to make sure the
+ * device name stays valid until its done with it.  We use
+ * rcu_read_lock() as well to make sure we're safe in case the caller
+ * gets sloppy, and because rcu_read_lock() is cheap and can be safely
+ * nested.
+ */
+struct devname_cache {
+        struct rcu_head rcu;
+        dev_t           device;
+        char            devname[BDEVNAME_SIZE];
+};
+#define CACHE_SIZE_BITS 6
+static struct devname_cache *devcache[1 << CACHE_SIZE_BITS];
+static DEFINE_SPINLOCK(devname_cache_lock);
+
+static void free_devcache(struct rcu_head *rcu)
+{
+        kfree(rcu);
+}
+
+const char *jbd2_dev_to_name(dev_t device)
+{
+        int     i = hash_32(device, CACHE_SIZE_BITS);
+        char    *ret;
+        struct block_device *bd;
+
+        rcu_read_lock();
+        if (devcache[i] && devcache[i]->device == device) {
+                ret = devcache[i]->devname;
+                rcu_read_unlock();
+                return ret;
+        }
+        rcu_read_unlock();
+
+        spin_lock(&devname_cache_lock);
+        if (devcache[i]) {
+                if (devcache[i]->device == device) {
+                        ret = devcache[i]->devname;
+                        spin_unlock(&devname_cache_lock);
+                        return ret;
+                }
+                call_rcu(&devcache[i]->rcu, free_devcache);
+        }
+        devcache[i] = kmalloc(sizeof(struct devname_cache), GFP_KERNEL);
+        if (!devcache[i]) {
+                spin_unlock(&devname_cache_lock);
+                return "NODEV-ALLOCFAILURE"; /* Something non-NULL */
+        }
+        devcache[i]->device = device;
+        bd = bdget(device);
+        if (bd) {
+                bdevname(bd, devcache[i]->devname);
+                bdput(bd);
+        } else
+                __bdevname(device, devcache[i]->devname);
+        ret = devcache[i]->devname;
+        spin_unlock(&devname_cache_lock);
+        return ret;
+}
+EXPORT_SYMBOL(jbd2_dev_to_name);
+
 MODULE_LICENSE("GPL");
 module_init(journal_init);
 module_exit(journal_exit);
diff --git a/include/linux/jbd2.h b/include/linux/jbd2.h
index cc02393bfce8..d97eb652d6ca 100644
--- a/include/linux/jbd2.h
+++ b/include/linux/jbd2.h
@@ -1315,6 +1315,12 @@ extern int jbd_blocks_per_page(struct inode *inode);
 #define BUFFER_TRACE2(bh, bh2, info)    do {} while (0)
 #define JBUFFER_TRACE(jh, info) do {} while (0)
 
+/* 
+ * jbd2_dev_to_name is a utility function used by the jbd2 and ext4 
+ * tracing infrastructure to map a dev_t to a device name.
+ */
+extern const char *jbd2_dev_to_name(dev_t device);
+
 #endif  /* __KERNEL__ */
 
 #endif  /* _LINUX_JBD2_H */
diff --git a/include/trace/events/jbd2.h b/include/trace/events/jbd2.h
new file mode 100644
index 000000000000..845b0b4b48fd
--- /dev/null
+++ b/include/trace/events/jbd2.h
@@ -0,0 +1,168 @@
+#if !defined(_TRACE_JBD2_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_JBD2_H
+
+#include <linux/jbd2.h>
+#include <linux/tracepoint.h>
+
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM jbd2
+
+TRACE_EVENT(jbd2_checkpoint,
+
+        TP_PROTO(journal_t *journal, int result),
+
+        TP_ARGS(journal, result),
+
+        TP_STRUCT__entry(
+                __field(        dev_t,  dev                     )
+                __field(        int,    result                  )
+        ),
+
+        TP_fast_assign(
+                __entry->dev            = journal->j_fs_dev->bd_dev;
+                __entry->result         = result;
+        ),
+
+        TP_printk("dev %s result %d",
+                  jbd2_dev_to_name(__entry->dev), __entry->result)
+);
+
+TRACE_EVENT(jbd2_start_commit,
+
+        TP_PROTO(journal_t *journal, transaction_t *commit_transaction),
+
+        TP_ARGS(journal, commit_transaction),
+
+        TP_STRUCT__entry(
+                __field(        dev_t,  dev                     )
+                __field(        char,   sync_commit               )
+                __field(        int,    transaction               )
+        ),
+
+        TP_fast_assign(
+                __entry->dev            = journal->j_fs_dev->bd_dev;
+                __entry->sync_commit = commit_transaction->t_synchronous_commit;
+                __entry->transaction    = commit_transaction->t_tid;
+        ),
+
+        TP_printk("dev %s transaction %d sync %d",
+                  jbd2_dev_to_name(__entry->dev), __entry->transaction,
+                  __entry->sync_commit)
+);
+
+TRACE_EVENT(jbd2_commit_locking,
+
+        TP_PROTO(journal_t *journal, transaction_t *commit_transaction),
+
+        TP_ARGS(journal, commit_transaction),
+
+        TP_STRUCT__entry(
+                __field(        dev_t,  dev                     )
+                __field(        char,   sync_commit               )
+                __field(        int,    transaction               )
+        ),
+
+        TP_fast_assign(
+                __entry->dev            = journal->j_fs_dev->bd_dev;
+                __entry->sync_commit = commit_transaction->t_synchronous_commit;
+                __entry->transaction    = commit_transaction->t_tid;
+        ),
+
+        TP_printk("dev %s transaction %d sync %d",
+                  jbd2_dev_to_name(__entry->dev), __entry->transaction,
+                  __entry->sync_commit)
+);
+
+TRACE_EVENT(jbd2_commit_flushing,
+
+        TP_PROTO(journal_t *journal, transaction_t *commit_transaction),
+
+        TP_ARGS(journal, commit_transaction),
+
+        TP_STRUCT__entry(
+                __field(        dev_t,  dev                     )
+                __field(        char,   sync_commit               )
+                __field(        int,    transaction               )
+        ),
+
+        TP_fast_assign(
+                __entry->dev            = journal->j_fs_dev->bd_dev;
+                __entry->sync_commit = commit_transaction->t_synchronous_commit;
+                __entry->transaction    = commit_transaction->t_tid;
+        ),
+
+        TP_printk("dev %s transaction %d sync %d",
+                  jbd2_dev_to_name(__entry->dev), __entry->transaction,
+                  __entry->sync_commit)
+);
+
+TRACE_EVENT(jbd2_commit_logging,
+
+        TP_PROTO(journal_t *journal, transaction_t *commit_transaction),
+
+        TP_ARGS(journal, commit_transaction),
+
+        TP_STRUCT__entry(
+                __field(        dev_t,  dev                     )
+                __field(        char,   sync_commit               )
+                __field(        int,    transaction               )
+        ),
+
+        TP_fast_assign(
+                __entry->dev            = journal->j_fs_dev->bd_dev;
+                __entry->sync_commit = commit_transaction->t_synchronous_commit;
+                __entry->transaction    = commit_transaction->t_tid;
+        ),
+
+        TP_printk("dev %s transaction %d sync %d",
+                  jbd2_dev_to_name(__entry->dev), __entry->transaction,
+                  __entry->sync_commit)
+);
+
+TRACE_EVENT(jbd2_end_commit,
+        TP_PROTO(journal_t *journal, transaction_t *commit_transaction),
+
+        TP_ARGS(journal, commit_transaction),
+
+        TP_STRUCT__entry(
+                __field(        dev_t,  dev                     )
+                __field(        char,   sync_commit               )
+                __field(        int,    transaction               )
+                __field(        int,    head                      )
+        ),
+
+        TP_fast_assign(
+                __entry->dev            = journal->j_fs_dev->bd_dev;
+                __entry->sync_commit = commit_transaction->t_synchronous_commit;
+                __entry->transaction    = commit_transaction->t_tid;
+                __entry->head           = journal->j_tail_sequence;
+        ),
+
+        TP_printk("dev %s transaction %d sync %d head %d",
+                  jbd2_dev_to_name(__entry->dev), __entry->transaction,
+                  __entry->sync_commit, __entry->head)
+);
+
+TRACE_EVENT(jbd2_submit_inode_data,
+        TP_PROTO(struct inode *inode),
+
+        TP_ARGS(inode),
+
+        TP_STRUCT__entry(
+                __field(        dev_t,  dev                     )
+                __field(        ino_t,  ino                     )
+        ),
+
+        TP_fast_assign(
+                __entry->dev    = inode->i_sb->s_dev;
+                __entry->ino    = inode->i_ino;
+        ),
+
+        TP_printk("dev %s ino %lu",
+                  jbd2_dev_to_name(__entry->dev), __entry->ino)
+);
+
+#endif /* _TRACE_JBD2_H */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>