diff options
-rw-r--r-- | fs/jbd2/transaction.c | 8 | ||||
-rw-r--r-- | include/trace/events/jbd2.h | 21 |
2 files changed, 29 insertions, 0 deletions
diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c index a1920da2280..10f524c59ea 100644 --- a/fs/jbd2/transaction.c +++ b/fs/jbd2/transaction.c @@ -639,6 +639,7 @@ do_get_write_access(handle_t *handle, struct journal_head *jh, int error; char *frozen_buffer = NULL; int need_copy = 0; + unsigned long start_lock, time_lock; if (is_handle_aborted(handle)) return -EROFS; @@ -654,9 +655,16 @@ repeat: /* @@@ Need to check for errors here at some point. */ + start_lock = jiffies; lock_buffer(bh); jbd_lock_bh_state(bh); + /* If it takes too long to lock the buffer, trace it */ + time_lock = jbd2_time_diff(start_lock, jiffies); + if (time_lock > HZ/10) + trace_jbd2_lock_buffer_stall(bh->b_bdev->bd_dev, + jiffies_to_msecs(time_lock)); + /* We now hold the buffer lock so it is safe to query the buffer * state. Is the buffer dirty? * diff --git a/include/trace/events/jbd2.h b/include/trace/events/jbd2.h index 070df49e4a1..c1d1f3eb242 100644 --- a/include/trace/events/jbd2.h +++ b/include/trace/events/jbd2.h @@ -358,6 +358,27 @@ TRACE_EVENT(jbd2_write_superblock, MINOR(__entry->dev), __entry->write_op) ); +TRACE_EVENT(jbd2_lock_buffer_stall, + + TP_PROTO(dev_t dev, unsigned long stall_ms), + + TP_ARGS(dev, stall_ms), + + TP_STRUCT__entry( + __field( dev_t, dev ) + __field(unsigned long, stall_ms ) + ), + + TP_fast_assign( + __entry->dev = dev; + __entry->stall_ms = stall_ms; + ), + + TP_printk("dev %d,%d stall_ms %lu", + MAJOR(__entry->dev), MINOR(__entry->dev), + __entry->stall_ms) +); + #endif /* _TRACE_JBD2_H */ /* This part must be outside protection */ |