From 9fb0a7da0c528d9bd49b597aa63b1fe2216c7203 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Fri, 11 Jan 2013 13:06:37 -0800 Subject: [PATCH] writeback: add more tracepoints Add tracepoints for page dirtying, writeback_single_inode start, inode dirtying and writeback. For the latter two inode events, a pair of events are defined to denote start and end of the operations (the starting one has _start suffix and the one w/o suffix happens after the operation is complete). These inode ops are FS specific and can be non-trivial and having enclosing tracepoints is useful for external tracers. This is part of tracepoint additions to improve visiblity into dirtying / writeback operations for io tracer and userland. v2: writeback_dirty_inode[_start] TPs may be called for files on pseudo FSes w/ unregistered bdi. Check whether bdi->dev is %NULL before dereferencing. v3: buffer dirtying moved to a block TP. Signed-off-by: Tejun Heo Reviewed-by: Jan Kara Signed-off-by: Jens Axboe --- fs/fs-writeback.c | 16 ++++- include/trace/events/writeback.h | 116 +++++++++++++++++++++++++++++++ mm/page-writeback.c | 2 + 3 files changed, 132 insertions(+), 2 deletions(-) diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c index 310972b72a66..359494ea1bde 100644 --- a/fs/fs-writeback.c +++ b/fs/fs-writeback.c @@ -318,8 +318,14 @@ static void queue_io(struct bdi_writeback *wb, struct wb_writeback_work *work) static int write_inode(struct inode *inode, struct writeback_control *wbc) { - if (inode->i_sb->s_op->write_inode && !is_bad_inode(inode)) - return inode->i_sb->s_op->write_inode(inode, wbc); + int ret; + + if (inode->i_sb->s_op->write_inode && !is_bad_inode(inode)) { + trace_writeback_write_inode_start(inode, wbc); + ret = inode->i_sb->s_op->write_inode(inode, wbc); + trace_writeback_write_inode(inode, wbc); + return ret; + } return 0; } @@ -450,6 +456,8 @@ __writeback_single_inode(struct inode *inode, struct writeback_control *wbc) WARN_ON(!(inode->i_state & I_SYNC)); + trace_writeback_single_inode_start(inode, wbc, nr_to_write); + ret = do_writepages(mapping, wbc); /* @@ -1150,8 +1158,12 @@ void __mark_inode_dirty(struct inode *inode, int flags) * dirty the inode itself */ if (flags & (I_DIRTY_SYNC | I_DIRTY_DATASYNC)) { + trace_writeback_dirty_inode_start(inode, flags); + if (sb->s_op->dirty_inode) sb->s_op->dirty_inode(inode, flags); + + trace_writeback_dirty_inode(inode, flags); } /* diff --git a/include/trace/events/writeback.h b/include/trace/events/writeback.h index b453d92c2253..6a16fd2e70ed 100644 --- a/include/trace/events/writeback.h +++ b/include/trace/events/writeback.h @@ -32,6 +32,115 @@ struct wb_writeback_work; +TRACE_EVENT(writeback_dirty_page, + + TP_PROTO(struct page *page, struct address_space *mapping), + + TP_ARGS(page, mapping), + + TP_STRUCT__entry ( + __array(char, name, 32) + __field(unsigned long, ino) + __field(pgoff_t, index) + ), + + TP_fast_assign( + strncpy(__entry->name, + mapping ? dev_name(mapping->backing_dev_info->dev) : "(unknown)", 32); + __entry->ino = mapping ? mapping->host->i_ino : 0; + __entry->index = page->index; + ), + + TP_printk("bdi %s: ino=%lu index=%lu", + __entry->name, + __entry->ino, + __entry->index + ) +); + +DECLARE_EVENT_CLASS(writeback_dirty_inode_template, + + TP_PROTO(struct inode *inode, int flags), + + TP_ARGS(inode, flags), + + TP_STRUCT__entry ( + __array(char, name, 32) + __field(unsigned long, ino) + __field(unsigned long, flags) + ), + + TP_fast_assign( + struct backing_dev_info *bdi = inode->i_mapping->backing_dev_info; + + /* may be called for files on pseudo FSes w/ unregistered bdi */ + strncpy(__entry->name, + bdi->dev ? dev_name(bdi->dev) : "(unknown)", 32); + __entry->ino = inode->i_ino; + __entry->flags = flags; + ), + + TP_printk("bdi %s: ino=%lu flags=%s", + __entry->name, + __entry->ino, + show_inode_state(__entry->flags) + ) +); + +DEFINE_EVENT(writeback_dirty_inode_template, writeback_dirty_inode_start, + + TP_PROTO(struct inode *inode, int flags), + + TP_ARGS(inode, flags) +); + +DEFINE_EVENT(writeback_dirty_inode_template, writeback_dirty_inode, + + TP_PROTO(struct inode *inode, int flags), + + TP_ARGS(inode, flags) +); + +DECLARE_EVENT_CLASS(writeback_write_inode_template, + + TP_PROTO(struct inode *inode, struct writeback_control *wbc), + + TP_ARGS(inode, wbc), + + TP_STRUCT__entry ( + __array(char, name, 32) + __field(unsigned long, ino) + __field(int, sync_mode) + ), + + TP_fast_assign( + strncpy(__entry->name, + dev_name(inode->i_mapping->backing_dev_info->dev), 32); + __entry->ino = inode->i_ino; + __entry->sync_mode = wbc->sync_mode; + ), + + TP_printk("bdi %s: ino=%lu sync_mode=%d", + __entry->name, + __entry->ino, + __entry->sync_mode + ) +); + +DEFINE_EVENT(writeback_write_inode_template, writeback_write_inode_start, + + TP_PROTO(struct inode *inode, struct writeback_control *wbc), + + TP_ARGS(inode, wbc) +); + +DEFINE_EVENT(writeback_write_inode_template, writeback_write_inode, + + TP_PROTO(struct inode *inode, struct writeback_control *wbc), + + TP_ARGS(inode, wbc) +); + DECLARE_EVENT_CLASS(writeback_work_class, TP_PROTO(struct backing_dev_info *bdi, struct wb_writeback_work *work), TP_ARGS(bdi, work), @@ -479,6 +588,13 @@ DECLARE_EVENT_CLASS(writeback_single_inode_template, ) ); +DEFINE_EVENT(writeback_single_inode_template, writeback_single_inode_start, + TP_PROTO(struct inode *inode, + struct writeback_control *wbc, + unsigned long nr_to_write), + TP_ARGS(inode, wbc, nr_to_write) +); + DEFINE_EVENT(writeback_single_inode_template, writeback_single_inode, TP_PROTO(struct inode *inode, struct writeback_control *wbc, diff --git a/mm/page-writeback.c b/mm/page-writeback.c index 0713bfbf0954..3734cefd4de4 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -1982,6 +1982,8 @@ int __set_page_dirty_no_writeback(struct page *page) */ void account_page_dirtied(struct page *page, struct address_space *mapping) { + trace_writeback_dirty_page(page, mapping); + if (mapping_cap_account_dirty(mapping)) { __inc_zone_page_state(page, NR_FILE_DIRTY); __inc_zone_page_state(page, NR_DIRTIED); -- 2.34.1