diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c index c8471b3ddccf..73acab4dc2b7 100644 --- a/fs/fs-writeback.c +++ b/fs/fs-writeback.c @@ -26,15 +26,9 @@ #include #include #include +#include #include "internal.h" -#define inode_to_bdi(inode) ((inode)->i_mapping->backing_dev_info) - -/* - * We don't actually have pdflush, but this one is exported though /proc... - */ -int nr_pdflush_threads; - /* * Passed into wb_writeback(), essentially a subset of writeback_control */ @@ -50,6 +44,21 @@ struct wb_writeback_work { struct completion *done; /* set if the caller waits */ }; +/* + * Include the creation of the trace points after defining the + * wb_writeback_work structure so that the definition remains local to this + * file. + */ +#define CREATE_TRACE_POINTS +#include + +#define inode_to_bdi(inode) ((inode)->i_mapping->backing_dev_info) + +/* + * We don't actually have pdflush, but this one is exported though /proc... + */ +int nr_pdflush_threads; + /** * writeback_in_progress - determine whether there is writeback in progress * @bdi: the device's backing_dev_info structure. @@ -65,6 +74,8 @@ int writeback_in_progress(struct backing_dev_info *bdi) static void bdi_queue_work(struct backing_dev_info *bdi, struct wb_writeback_work *work) { + trace_writeback_queue(bdi, work); + spin_lock(&bdi->wb_lock); list_add_tail(&work->list, &bdi->work_list); spin_unlock(&bdi->wb_lock); @@ -74,6 +85,7 @@ static void bdi_queue_work(struct backing_dev_info *bdi, * it gets created and wakes up, we'll run this work. */ if (unlikely(!bdi->wb.task)) { + trace_writeback_nothread(bdi, work); wake_up_process(default_backing_dev_info.wb.task); } else { struct bdi_writeback *wb = &bdi->wb; @@ -95,8 +107,10 @@ __bdi_start_writeback(struct backing_dev_info *bdi, long nr_pages, */ work = kzalloc(sizeof(*work), GFP_ATOMIC); if (!work) { - if (bdi->wb.task) + if (bdi->wb.task) { + trace_writeback_nowork(bdi); wake_up_process(bdi->wb.task); + } return; } @@ -751,6 +765,8 @@ long wb_do_writeback(struct bdi_writeback *wb, int force_wait) if (force_wait) work->sync_mode = WB_SYNC_ALL; + trace_writeback_exec(bdi, work); + wrote += wb_writeback(wb, work); /* @@ -805,9 +821,13 @@ int bdi_writeback_thread(void *data) smp_mb__after_clear_bit(); wake_up_bit(&bdi->state, BDI_pending); + trace_writeback_thread_start(bdi); + while (!kthread_should_stop()) { pages_written = wb_do_writeback(wb, 0); + trace_writeback_pages_written(pages_written); + if (pages_written) last_active = jiffies; else if (wait_jiffies != -1UL) { @@ -845,6 +865,8 @@ int bdi_writeback_thread(void *data) */ if (!list_empty(&bdi->work_list)) wb_do_writeback(wb, 1); + + trace_writeback_thread_stop(bdi); return 0; } diff --git a/include/trace/events/writeback.h b/include/trace/events/writeback.h new file mode 100644 index 000000000000..562fcae10d9d --- /dev/null +++ b/include/trace/events/writeback.h @@ -0,0 +1,91 @@ +#undef TRACE_SYSTEM +#define TRACE_SYSTEM writeback + +#if !defined(_TRACE_WRITEBACK_H) || defined(TRACE_HEADER_MULTI_READ) +#define _TRACE_WRITEBACK_H + +#include +#include + +struct wb_writeback_work; + +DECLARE_EVENT_CLASS(writeback_work_class, + TP_PROTO(struct backing_dev_info *bdi, struct wb_writeback_work *work), + TP_ARGS(bdi, work), + TP_STRUCT__entry( + __array(char, name, 32) + __field(long, nr_pages) + __field(dev_t, sb_dev) + __field(int, sync_mode) + __field(int, for_kupdate) + __field(int, range_cyclic) + __field(int, for_background) + ), + TP_fast_assign( + strncpy(__entry->name, dev_name(bdi->dev), 32); + __entry->nr_pages = work->nr_pages; + __entry->sb_dev = work->sb ? work->sb->s_dev : 0; + __entry->sync_mode = work->sync_mode; + __entry->for_kupdate = work->for_kupdate; + __entry->range_cyclic = work->range_cyclic; + __entry->for_background = work->for_background; + ), + TP_printk("bdi %s: sb_dev %d:%d nr_pages=%ld sync_mode=%d " + "kupdate=%d range_cyclic=%d background=%d", + __entry->name, + MAJOR(__entry->sb_dev), MINOR(__entry->sb_dev), + __entry->nr_pages, + __entry->sync_mode, + __entry->for_kupdate, + __entry->range_cyclic, + __entry->for_background + ) +); +#define DEFINE_WRITEBACK_WORK_EVENT(name) \ +DEFINE_EVENT(writeback_work_class, name, \ + TP_PROTO(struct backing_dev_info *bdi, struct wb_writeback_work *work), \ + TP_ARGS(bdi, work)) +DEFINE_WRITEBACK_WORK_EVENT(writeback_nothread); +DEFINE_WRITEBACK_WORK_EVENT(writeback_queue); +DEFINE_WRITEBACK_WORK_EVENT(writeback_exec); + +TRACE_EVENT(writeback_pages_written, + TP_PROTO(long pages_written), + TP_ARGS(pages_written), + TP_STRUCT__entry( + __field(long, pages) + ), + TP_fast_assign( + __entry->pages = pages_written; + ), + TP_printk("%ld", __entry->pages) +); + +DECLARE_EVENT_CLASS(writeback_class, + TP_PROTO(struct backing_dev_info *bdi), + TP_ARGS(bdi), + TP_STRUCT__entry( + __array(char, name, 32) + ), + TP_fast_assign( + strncpy(__entry->name, dev_name(bdi->dev), 32); + ), + TP_printk("bdi %s", + __entry->name + ) +); +#define DEFINE_WRITEBACK_EVENT(name) \ +DEFINE_EVENT(writeback_class, name, \ + TP_PROTO(struct backing_dev_info *bdi), \ + TP_ARGS(bdi)) + +DEFINE_WRITEBACK_EVENT(writeback_nowork); +DEFINE_WRITEBACK_EVENT(writeback_bdi_register); +DEFINE_WRITEBACK_EVENT(writeback_bdi_unregister); +DEFINE_WRITEBACK_EVENT(writeback_thread_start); +DEFINE_WRITEBACK_EVENT(writeback_thread_stop); + +#endif /* _TRACE_WRITEBACK_H */ + +/* This part must be outside protection */ +#include diff --git a/mm/backing-dev.c b/mm/backing-dev.c index bceac647e4d1..ac78a3336181 100644 --- a/mm/backing-dev.c +++ b/mm/backing-dev.c @@ -10,6 +10,7 @@ #include #include #include +#include static atomic_long_t bdi_seq = ATOMIC_LONG_INIT(0); @@ -518,6 +519,7 @@ int bdi_register(struct backing_dev_info *bdi, struct device *parent, bdi_debug_register(bdi, dev_name(dev)); set_bit(BDI_registered, &bdi->state); + trace_writeback_bdi_register(bdi); exit: return ret; } @@ -578,6 +580,7 @@ static void bdi_prune_sb(struct backing_dev_info *bdi) void bdi_unregister(struct backing_dev_info *bdi) { if (bdi->dev) { + trace_writeback_bdi_unregister(bdi); bdi_prune_sb(bdi); if (!bdi_cap_flush_forker(bdi))