sched_ext: Maintain an online cid mask in the scheduler arenagrafted

Schedulers on the default cid mapping treat [0, nr_online_cids) as the
online set and restart on hotplug. Schedulers that install their own mapping
with scx_bpf_cid_override() have no way to learn which cids are online: the
count no longer identifies members and the CPU-form cpumask is unusable from
cid programs. This is an obvious hole in the cid API.

Add scx_bpf_online_cmask(), a kernel-maintained cmask in the scheduler's
arena, allocated alongside the per-CPU scratch masks and populated after the
cid mapping is finalized and before ops.init(), for child schedulers too.
The pointer stays valid through ops.exit() with no reference to take. It is
the arena offset as a void pointer, the same form struct_ops arena arguments
arrive in. The verifier types the void return as a scalar for the program's
arena cast.

The mask follows the SCX hotplug notifications: seeded from cpu_active_mask
and updated before ops.cid_online/offline() runs, so it lags cpu_online_mask
only inside a hotplug transition. Updates walk the scheduler list under the
lock that also serializes unlinking. Reads are live, not atomic snapshots.
Root initialization excludes hotplug.

v2: Reworded the getter kerneldoc (Andrea Righi).

Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Andrea Righi <arighi@nvidia.com>

1 files changed, 886 insertions, 0 deletions

diff --git a/include/trace/events/writeback.h b/include/trace/events/writeback.h
new file mode 100644
index 000000000..13ee076cc
--- /dev/null
+++ b/include/trace/events/writeback.h
@@ -0,0 +1,886 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM writeback
+
+#if !defined(_TRACE_WRITEBACK_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_WRITEBACK_H
+
+#include <linux/tracepoint.h>
+#include <linux/backing-dev.h>
+#include <linux/writeback.h>
+
+#define show_inode_state(state)					\
+	__print_flags(state, "|",				\
+		{I_DIRTY_SYNC,		"I_DIRTY_SYNC"},	\
+		{I_DIRTY_DATASYNC,	"I_DIRTY_DATASYNC"},	\
+		{I_DIRTY_PAGES,		"I_DIRTY_PAGES"},	\
+		{I_NEW,			"I_NEW"},		\
+		{I_WILL_FREE,		"I_WILL_FREE"},		\
+		{I_FREEING,		"I_FREEING"},		\
+		{I_CLEAR,		"I_CLEAR"},		\
+		{I_SYNC,		"I_SYNC"},		\
+		{I_DIRTY_TIME,		"I_DIRTY_TIME"},	\
+		{I_REFERENCED,		"I_REFERENCED"},	\
+		{I_LINKABLE,		"I_LINKABLE"},		\
+		{I_WB_SWITCH,		"I_WB_SWITCH"},		\
+		{I_OVL_INUSE,		"I_OVL_INUSE"},		\
+		{I_CREATING,		"I_CREATING"},		\
+		{I_DONTCACHE,		"I_DONTCACHE"},		\
+		{I_SYNC_QUEUED,		"I_SYNC_QUEUED"},	\
+		{I_PINNING_NETFS_WB,	"I_PINNING_NETFS_WB"},	\
+		{I_LRU_ISOLATING,	"I_LRU_ISOLATING"}	\
+	)
+
+/* enums need to be exported to user space */
+#undef EM
+#undef EMe
+#define EM(a,b) 	TRACE_DEFINE_ENUM(a);
+#define EMe(a,b)	TRACE_DEFINE_ENUM(a);
+
+#define WB_WORK_REASON							\
+	EM( WB_REASON_BACKGROUND,		"background")		\
+	EM( WB_REASON_VMSCAN,			"vmscan")		\
+	EM( WB_REASON_SYNC,			"sync")			\
+	EM( WB_REASON_PERIODIC,			"periodic")		\
+	EM( WB_REASON_FS_FREE_SPACE,		"fs_free_space")	\
+	EM( WB_REASON_FORKER_THREAD,		"forker_thread")	\
+	EM( WB_REASON_FOREIGN_FLUSH,		"foreign_flush")	\
+	EMe(WB_REASON_DONTCACHE,		"dontcache")
+
+WB_WORK_REASON
+
+/*
+ * Now redefine the EM() and EMe() macros to map the enums to the strings
+ * that will be printed in the output.
+ */
+#undef EM
+#undef EMe
+#define EM(a,b)		{ a, b },
+#define EMe(a,b)	{ a, b }
+
+struct wb_writeback_work;
+
+DECLARE_EVENT_CLASS(writeback_folio_template,
+
+	TP_PROTO(struct folio *folio, struct address_space *mapping),
+
+	TP_ARGS(folio, mapping),
+
+	TP_STRUCT__entry (
+		__array(char, name, 32)
+		__field(u64, ino)
+		__field(pgoff_t, index)
+	),
+
+	TP_fast_assign(
+		strscpy_pad(__entry->name,
+			    bdi_dev_name(mapping ? inode_to_bdi(mapping->host) :
+					 NULL), 32);
+		__entry->ino = (mapping && mapping->host) ? mapping->host->i_ino : 0;
+		__entry->index = folio->index;
+	),
+
+	TP_printk("bdi %s: ino=%llu index=%lu",
+		__entry->name,
+		__entry->ino,
+		__entry->index
+	)
+);
+
+DEFINE_EVENT(writeback_folio_template, writeback_dirty_folio,
+
+	TP_PROTO(struct folio *folio, struct address_space *mapping),
+
+	TP_ARGS(folio, mapping)
+);
+
+DEFINE_EVENT(writeback_folio_template, folio_wait_writeback,
+
+	TP_PROTO(struct folio *folio, struct address_space *mapping),
+
+	TP_ARGS(folio, mapping)
+);
+
+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(u64, ino)
+		__field(unsigned long, state)
+		__field(unsigned long, flags)
+	),
+
+	TP_fast_assign(
+		struct backing_dev_info *bdi = inode_to_bdi(inode);
+
+		/* may be called for files on pseudo FSes w/ unregistered bdi */
+		strscpy_pad(__entry->name, bdi_dev_name(bdi), 32);
+		__entry->ino		= inode->i_ino;
+		__entry->state		= inode_state_read_once(inode);
+		__entry->flags		= flags;
+	),
+
+	TP_printk("bdi %s: ino=%llu state=%s flags=%s",
+		__entry->name,
+		__entry->ino,
+		show_inode_state(__entry->state),
+		show_inode_state(__entry->flags)
+	)
+);
+
+DEFINE_EVENT(writeback_dirty_inode_template, writeback_mark_inode_dirty,
+
+	TP_PROTO(struct inode *inode, int flags),
+
+	TP_ARGS(inode, 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)
+);
+
+#ifdef CREATE_TRACE_POINTS
+#ifdef CONFIG_CGROUP_WRITEBACK
+
+static inline u64 __trace_wb_assign_cgroup(struct bdi_writeback *wb)
+{
+	return cgroup_ino(wb->memcg_css->cgroup);
+}
+
+static inline u64 __trace_wbc_assign_cgroup(struct writeback_control *wbc)
+{
+	if (wbc->wb)
+		return __trace_wb_assign_cgroup(wbc->wb);
+	else
+		return 1;
+}
+#else	/* CONFIG_CGROUP_WRITEBACK */
+
+static inline u64 __trace_wb_assign_cgroup(struct bdi_writeback *wb)
+{
+	return 1;
+}
+
+static inline u64 __trace_wbc_assign_cgroup(struct writeback_control *wbc)
+{
+	return 1;
+}
+
+#endif	/* CONFIG_CGROUP_WRITEBACK */
+#endif	/* CREATE_TRACE_POINTS */
+
+#ifdef CONFIG_CGROUP_WRITEBACK
+TRACE_EVENT(inode_foreign_history,
+
+	TP_PROTO(struct inode *inode, struct writeback_control *wbc,
+		 unsigned int history),
+
+	TP_ARGS(inode, wbc, history),
+
+	TP_STRUCT__entry(
+		__array(char,		name, 32)
+		__field(u64,		ino)
+		__field(u64,		cgroup_ino)
+		__field(unsigned int,	history)
+	),
+
+	TP_fast_assign(
+		strscpy_pad(__entry->name, bdi_dev_name(inode_to_bdi(inode)), 32);
+		__entry->ino		= inode->i_ino;
+		__entry->cgroup_ino	= __trace_wbc_assign_cgroup(wbc);
+		__entry->history	= history;
+	),
+
+	TP_printk("bdi %s: ino=%llu cgroup_ino=%llu history=0x%x",
+		__entry->name,
+		__entry->ino,
+		__entry->cgroup_ino,
+		__entry->history
+	)
+);
+
+TRACE_EVENT(inode_switch_wbs_queue,
+
+	TP_PROTO(struct bdi_writeback *old_wb, struct bdi_writeback *new_wb,
+		 unsigned int count),
+
+	TP_ARGS(old_wb, new_wb, count),
+
+	TP_STRUCT__entry(
+		__array(char,		name, 32)
+		__field(u64,		old_cgroup_ino)
+		__field(u64,		new_cgroup_ino)
+		__field(unsigned int,	count)
+	),
+
+	TP_fast_assign(
+		strscpy_pad(__entry->name, bdi_dev_name(old_wb->bdi), 32);
+		__entry->old_cgroup_ino	= __trace_wb_assign_cgroup(old_wb);
+		__entry->new_cgroup_ino	= __trace_wb_assign_cgroup(new_wb);
+		__entry->count		= count;
+	),
+
+	TP_printk("bdi %s: old_cgroup_ino=%llu new_cgroup_ino=%llu count=%u",
+		__entry->name,
+		__entry->old_cgroup_ino,
+		__entry->new_cgroup_ino,
+		__entry->count
+	)
+);
+
+TRACE_EVENT(inode_switch_wbs,
+
+	TP_PROTO(struct inode *inode, struct bdi_writeback *old_wb,
+		 struct bdi_writeback *new_wb),
+
+	TP_ARGS(inode, old_wb, new_wb),
+
+	TP_STRUCT__entry(
+		__array(char,		name, 32)
+		__field(u64,		ino)
+		__field(u64,		old_cgroup_ino)
+		__field(u64,		new_cgroup_ino)
+	),
+
+	TP_fast_assign(
+		strscpy_pad(__entry->name, bdi_dev_name(old_wb->bdi), 32);
+		__entry->ino		= inode->i_ino;
+		__entry->old_cgroup_ino	= __trace_wb_assign_cgroup(old_wb);
+		__entry->new_cgroup_ino	= __trace_wb_assign_cgroup(new_wb);
+	),
+
+	TP_printk("bdi %s: ino=%llu old_cgroup_ino=%llu new_cgroup_ino=%llu",
+		__entry->name,
+		__entry->ino,
+		__entry->old_cgroup_ino,
+		__entry->new_cgroup_ino
+	)
+);
+
+TRACE_EVENT(track_foreign_dirty,
+
+	TP_PROTO(struct folio *folio, struct bdi_writeback *wb),
+
+	TP_ARGS(folio, wb),
+
+	TP_STRUCT__entry(
+		__array(char,		name, 32)
+		__field(u64,		bdi_id)
+		__field(u64,		ino)
+		__field(u64,		cgroup_ino)
+		__field(u64,		page_cgroup_ino)
+		__field(unsigned int,	memcg_id)
+	),
+
+	TP_fast_assign(
+		struct address_space *mapping = folio_mapping(folio);
+		struct inode *inode = mapping ? mapping->host : NULL;
+
+		strscpy_pad(__entry->name, bdi_dev_name(wb->bdi), 32);
+		__entry->bdi_id		= wb->bdi->id;
+		__entry->ino		= inode ? inode->i_ino : 0;
+		__entry->memcg_id	= wb->memcg_css->id;
+		__entry->cgroup_ino	= __trace_wb_assign_cgroup(wb);
+
+		rcu_read_lock();
+		__entry->page_cgroup_ino = cgroup_ino(folio_memcg(folio)->css.cgroup);
+		rcu_read_unlock();
+	),
+
+	TP_printk("bdi %s[%llu]: ino=%llu memcg_id=%u cgroup_ino=%llu page_cgroup_ino=%llu",
+		__entry->name,
+		__entry->bdi_id,
+		__entry->ino,
+		__entry->memcg_id,
+		__entry->cgroup_ino,
+		__entry->page_cgroup_ino
+	)
+);
+
+TRACE_EVENT(flush_foreign,
+
+	TP_PROTO(struct bdi_writeback *wb, unsigned int frn_bdi_id,
+		 unsigned int frn_memcg_id),
+
+	TP_ARGS(wb, frn_bdi_id, frn_memcg_id),
+
+	TP_STRUCT__entry(
+		__array(char,		name, 32)
+		__field(u64,		cgroup_ino)
+		__field(unsigned int,	frn_bdi_id)
+		__field(unsigned int,	frn_memcg_id)
+	),
+
+	TP_fast_assign(
+		strscpy_pad(__entry->name, bdi_dev_name(wb->bdi), 32);
+		__entry->cgroup_ino	= __trace_wb_assign_cgroup(wb);
+		__entry->frn_bdi_id	= frn_bdi_id;
+		__entry->frn_memcg_id	= frn_memcg_id;
+	),
+
+	TP_printk("bdi %s: cgroup_ino=%llu frn_bdi_id=%u frn_memcg_id=%u",
+		__entry->name,
+		__entry->cgroup_ino,
+		__entry->frn_bdi_id,
+		__entry->frn_memcg_id
+	)
+);
+#endif
+
+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(u64, ino)
+		__field(u64, cgroup_ino)
+		__field(int, sync_mode)
+	),
+
+	TP_fast_assign(
+		strscpy_pad(__entry->name,
+			    bdi_dev_name(inode_to_bdi(inode)), 32);
+		__entry->ino		= inode->i_ino;
+		__entry->sync_mode	= wbc->sync_mode;
+		__entry->cgroup_ino	= __trace_wbc_assign_cgroup(wbc);
+	),
+
+	TP_printk("bdi %s: ino=%llu sync_mode=%d cgroup_ino=%llu",
+		__entry->name,
+		__entry->ino,
+		__entry->sync_mode,
+		__entry->cgroup_ino
+	)
+);
+
+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 bdi_writeback *wb, struct wb_writeback_work *work),
+	TP_ARGS(wb, work),
+	TP_STRUCT__entry(
+		__array(char, name, 32)
+		__field(u64, cgroup_ino)
+		__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)
+		__field(int, reason)
+	),
+	TP_fast_assign(
+		strscpy_pad(__entry->name, bdi_dev_name(wb->bdi), 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;
+		__entry->reason = work->reason;
+		__entry->cgroup_ino = __trace_wb_assign_cgroup(wb);
+	),
+	TP_printk("bdi %s: sb_dev %d:%d nr_pages=%ld sync_mode=%d "
+		  "kupdate=%d range_cyclic=%d background=%d reason=%s cgroup_ino=%llu",
+		  __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,
+		  __print_symbolic(__entry->reason, WB_WORK_REASON),
+		  __entry->cgroup_ino
+	)
+);
+#define DEFINE_WRITEBACK_WORK_EVENT(name) \
+DEFINE_EVENT(writeback_work_class, name, \
+	TP_PROTO(struct bdi_writeback *wb, struct wb_writeback_work *work), \
+	TP_ARGS(wb, work))
+DEFINE_WRITEBACK_WORK_EVENT(writeback_queue);
+DEFINE_WRITEBACK_WORK_EVENT(writeback_exec);
+DEFINE_WRITEBACK_WORK_EVENT(writeback_start);
+DEFINE_WRITEBACK_WORK_EVENT(writeback_written);
+DEFINE_WRITEBACK_WORK_EVENT(writeback_wait);
+
+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 bdi_writeback *wb),
+	TP_ARGS(wb),
+	TP_STRUCT__entry(
+		__array(char, name, 32)
+		__field(u64, cgroup_ino)
+	),
+	TP_fast_assign(
+		strscpy_pad(__entry->name, bdi_dev_name(wb->bdi), 32);
+		__entry->cgroup_ino = __trace_wb_assign_cgroup(wb);
+	),
+	TP_printk("bdi %s: cgroup_ino=%llu",
+		  __entry->name,
+		  __entry->cgroup_ino
+	)
+);
+#define DEFINE_WRITEBACK_EVENT(name) \
+DEFINE_EVENT(writeback_class, name, \
+	TP_PROTO(struct bdi_writeback *wb), \
+	TP_ARGS(wb))
+
+DEFINE_WRITEBACK_EVENT(writeback_wake_background);
+
+TRACE_EVENT(writeback_bdi_register,
+	TP_PROTO(struct backing_dev_info *bdi),
+	TP_ARGS(bdi),
+	TP_STRUCT__entry(
+		__array(char, name, 32)
+	),
+	TP_fast_assign(
+		strscpy_pad(__entry->name, bdi_dev_name(bdi), 32);
+	),
+	TP_printk("bdi %s",
+		__entry->name
+	)
+);
+
+DECLARE_EVENT_CLASS(wbc_class,
+	TP_PROTO(struct writeback_control *wbc, struct backing_dev_info *bdi),
+	TP_ARGS(wbc, bdi),
+	TP_STRUCT__entry(
+		__array(char, name, 32)
+		__field(u64, cgroup_ino)
+		__field(long, nr_to_write)
+		__field(long, pages_skipped)
+		__field(long, range_start)
+		__field(long, range_end)
+		__field(int, sync_mode)
+		__field(int, for_kupdate)
+		__field(int, for_background)
+		__field(int, range_cyclic)
+	),
+
+	TP_fast_assign(
+		strscpy_pad(__entry->name, bdi_dev_name(bdi), 32);
+		__entry->nr_to_write	= wbc->nr_to_write;
+		__entry->pages_skipped	= wbc->pages_skipped;
+		__entry->sync_mode	= wbc->sync_mode;
+		__entry->for_kupdate	= wbc->for_kupdate;
+		__entry->for_background	= wbc->for_background;
+		__entry->range_cyclic	= wbc->range_cyclic;
+		__entry->range_start	= (long)wbc->range_start;
+		__entry->range_end	= (long)wbc->range_end;
+		__entry->cgroup_ino	= __trace_wbc_assign_cgroup(wbc);
+	),
+
+	TP_printk("bdi %s: towrt=%ld skip=%ld mode=%d kupd=%d bgrd=%d "
+		"cyclic=%d start=0x%lx end=0x%lx cgroup_ino=%llu",
+		__entry->name,
+		__entry->nr_to_write,
+		__entry->pages_skipped,
+		__entry->sync_mode,
+		__entry->for_kupdate,
+		__entry->for_background,
+		__entry->range_cyclic,
+		__entry->range_start,
+		__entry->range_end,
+		__entry->cgroup_ino
+	)
+)
+
+#define DEFINE_WBC_EVENT(name) \
+DEFINE_EVENT(wbc_class, name, \
+	TP_PROTO(struct writeback_control *wbc, struct backing_dev_info *bdi), \
+	TP_ARGS(wbc, bdi))
+DEFINE_WBC_EVENT(wbc_writepage);
+
+TRACE_EVENT(writeback_queue_io,
+	TP_PROTO(struct bdi_writeback *wb,
+		 struct wb_writeback_work *work,
+		 unsigned long dirtied_before,
+		 int moved),
+	TP_ARGS(wb, work, dirtied_before, moved),
+	TP_STRUCT__entry(
+		__array(char,		name, 32)
+		__field(u64,		cgroup_ino)
+		__field(unsigned long,	older)
+		__field(long,		age)
+		__field(int,		moved)
+		__field(int,		reason)
+	),
+	TP_fast_assign(
+		strscpy_pad(__entry->name, bdi_dev_name(wb->bdi), 32);
+		__entry->older	= dirtied_before;
+		__entry->age	= (jiffies - dirtied_before) * 1000 / HZ;
+		__entry->moved	= moved;
+		__entry->reason	= work->reason;
+		__entry->cgroup_ino	= __trace_wb_assign_cgroup(wb);
+	),
+	TP_printk("bdi %s: older=%lu age=%ld enqueue=%d reason=%s cgroup_ino=%llu",
+		__entry->name,
+		__entry->older,	/* dirtied_before in jiffies */
+		__entry->age,	/* dirtied_before in relative milliseconds */
+		__entry->moved,
+		__print_symbolic(__entry->reason, WB_WORK_REASON),
+		__entry->cgroup_ino
+	)
+);
+
+TRACE_EVENT(global_dirty_state,
+
+	TP_PROTO(unsigned long background_thresh,
+		 unsigned long dirty_thresh
+	),
+
+	TP_ARGS(background_thresh,
+		dirty_thresh
+	),
+
+	TP_STRUCT__entry(
+		__field(unsigned long,	nr_dirty)
+		__field(unsigned long,	nr_writeback)
+		__field(unsigned long,	background_thresh)
+		__field(unsigned long,	dirty_thresh)
+		__field(unsigned long,	dirty_limit)
+		__field(unsigned long,	nr_dirtied)
+		__field(unsigned long,	nr_written)
+	),
+
+	TP_fast_assign(
+		__entry->nr_dirty	= global_node_page_state(NR_FILE_DIRTY);
+		__entry->nr_writeback	= global_node_page_state(NR_WRITEBACK);
+		__entry->nr_dirtied	= global_node_page_state(NR_DIRTIED);
+		__entry->nr_written	= global_node_page_state(NR_WRITTEN);
+		__entry->background_thresh = background_thresh;
+		__entry->dirty_thresh	= dirty_thresh;
+		__entry->dirty_limit	= global_wb_domain.dirty_limit;
+	),
+
+	TP_printk("dirty=%lu writeback=%lu "
+		  "bg_thresh=%lu thresh=%lu limit=%lu "
+		  "dirtied=%lu written=%lu",
+		  __entry->nr_dirty,
+		  __entry->nr_writeback,
+		  __entry->background_thresh,
+		  __entry->dirty_thresh,
+		  __entry->dirty_limit,
+		  __entry->nr_dirtied,
+		  __entry->nr_written
+	)
+);
+
+#define KBps(x)			((x) << (PAGE_SHIFT - 10))
+
+TRACE_EVENT(bdi_dirty_ratelimit,
+
+	TP_PROTO(struct bdi_writeback *wb,
+		 unsigned long dirty_rate,
+		 unsigned long task_ratelimit),
+
+	TP_ARGS(wb, dirty_rate, task_ratelimit),
+
+	TP_STRUCT__entry(
+		__array(char,		bdi, 32)
+		__field(u64,		cgroup_ino)
+		__field(unsigned long,	write_bw)
+		__field(unsigned long,	avg_write_bw)
+		__field(unsigned long,	dirty_rate)
+		__field(unsigned long,	dirty_ratelimit)
+		__field(unsigned long,	task_ratelimit)
+		__field(unsigned long,	balanced_dirty_ratelimit)
+	),
+
+	TP_fast_assign(
+		strscpy_pad(__entry->bdi, bdi_dev_name(wb->bdi), 32);
+		__entry->write_bw	= KBps(wb->write_bandwidth);
+		__entry->avg_write_bw	= KBps(wb->avg_write_bandwidth);
+		__entry->dirty_rate	= KBps(dirty_rate);
+		__entry->dirty_ratelimit = KBps(wb->dirty_ratelimit);
+		__entry->task_ratelimit	= KBps(task_ratelimit);
+		__entry->balanced_dirty_ratelimit =
+					KBps(wb->balanced_dirty_ratelimit);
+		__entry->cgroup_ino	= __trace_wb_assign_cgroup(wb);
+	),
+
+	TP_printk("bdi %s: "
+		  "write_bw=%lu awrite_bw=%lu dirty_rate=%lu "
+		  "dirty_ratelimit=%lu task_ratelimit=%lu "
+		  "balanced_dirty_ratelimit=%lu cgroup_ino=%llu",
+		  __entry->bdi,
+		  __entry->write_bw,		/* write bandwidth */
+		  __entry->avg_write_bw,	/* avg write bandwidth */
+		  __entry->dirty_rate,		/* bdi dirty rate */
+		  __entry->dirty_ratelimit,	/* base ratelimit */
+		  __entry->task_ratelimit, /* ratelimit with position control */
+		  __entry->balanced_dirty_ratelimit, /* the balanced ratelimit */
+		  __entry->cgroup_ino
+	)
+);
+
+TRACE_EVENT(balance_dirty_pages,
+
+	TP_PROTO(struct bdi_writeback *wb,
+		 struct dirty_throttle_control *dtc,
+		 unsigned long dirty_ratelimit,
+		 unsigned long task_ratelimit,
+		 unsigned long dirtied,
+		 unsigned long period,
+		 long pause,
+		 unsigned long start_time),
+
+	TP_ARGS(wb, dtc,
+		dirty_ratelimit, task_ratelimit,
+		dirtied, period, pause, start_time),
+
+	TP_STRUCT__entry(
+		__array(	 char,	bdi, 32)
+		__field(u64,		cgroup_ino)
+		__field(unsigned long,	limit)
+		__field(unsigned long,	setpoint)
+		__field(unsigned long,	dirty)
+		__field(unsigned long,	wb_setpoint)
+		__field(unsigned long,	wb_dirty)
+		__field(unsigned long,	dirty_ratelimit)
+		__field(unsigned long,	task_ratelimit)
+		__field(unsigned long,	paused)
+		__field(	 long,	pause)
+		__field(unsigned long,	period)
+		__field(	 long,	think)
+		__field(unsigned int,	dirtied)
+		__field(unsigned int,	dirtied_pause)
+	),
+
+	TP_fast_assign(
+		unsigned long freerun = (dtc->thresh + dtc->bg_thresh) / 2;
+		strscpy_pad(__entry->bdi, bdi_dev_name(wb->bdi), 32);
+
+		__entry->limit		= dtc->limit;
+		__entry->setpoint	= (dtc->limit + freerun) / 2;
+		__entry->dirty		= dtc->dirty;
+		__entry->wb_setpoint	= __entry->setpoint *
+						dtc->wb_thresh / (dtc->thresh + 1);
+		__entry->wb_dirty	= dtc->wb_dirty;
+		__entry->dirty_ratelimit = KBps(dirty_ratelimit);
+		__entry->task_ratelimit	= KBps(task_ratelimit);
+		__entry->dirtied	= dirtied;
+		__entry->dirtied_pause	= current->nr_dirtied_pause;
+		__entry->think		= current->dirty_paused_when == 0 ? 0 :
+			 (long)(jiffies - current->dirty_paused_when) * 1000/HZ;
+		__entry->period		= period * 1000 / HZ;
+		__entry->pause		= pause * 1000 / HZ;
+		__entry->paused		= (jiffies - start_time) * 1000 / HZ;
+		__entry->cgroup_ino	= __trace_wb_assign_cgroup(wb);
+	),
+
+
+	TP_printk("bdi %s: "
+		  "limit=%lu setpoint=%lu dirty=%lu "
+		  "wb_setpoint=%lu wb_dirty=%lu "
+		  "dirty_ratelimit=%lu task_ratelimit=%lu "
+		  "dirtied=%u dirtied_pause=%u "
+		  "paused=%lu pause=%ld period=%lu think=%ld cgroup_ino=%llu",
+		  __entry->bdi,
+		  __entry->limit,
+		  __entry->setpoint,
+		  __entry->dirty,
+		  __entry->wb_setpoint,
+		  __entry->wb_dirty,
+		  __entry->dirty_ratelimit,
+		  __entry->task_ratelimit,
+		  __entry->dirtied,
+		  __entry->dirtied_pause,
+		  __entry->paused,	/* ms */
+		  __entry->pause,	/* ms */
+		  __entry->period,	/* ms */
+		  __entry->think,	/* ms */
+		  __entry->cgroup_ino
+	  )
+);
+
+TRACE_EVENT(writeback_sb_inodes_requeue,
+
+	TP_PROTO(struct inode *inode),
+	TP_ARGS(inode),
+
+	TP_STRUCT__entry(
+		__array(char, name, 32)
+		__field(u64, ino)
+		__field(u64, cgroup_ino)
+		__field(unsigned long, state)
+		__field(unsigned long, dirtied_when)
+	),
+
+	TP_fast_assign(
+		strscpy_pad(__entry->name,
+			    bdi_dev_name(inode_to_bdi(inode)), 32);
+		__entry->ino		= inode->i_ino;
+		__entry->state		= inode_state_read_once(inode);
+		__entry->dirtied_when	= inode->dirtied_when;
+		__entry->cgroup_ino	= __trace_wb_assign_cgroup(inode_to_wb(inode));
+	),
+
+	TP_printk("bdi %s: ino=%llu state=%s dirtied_when=%lu age=%lu cgroup_ino=%llu",
+		  __entry->name,
+		  __entry->ino,
+		  show_inode_state(__entry->state),
+		  __entry->dirtied_when,
+		  (jiffies - __entry->dirtied_when) / HZ,
+		  __entry->cgroup_ino
+	)
+);
+
+DECLARE_EVENT_CLASS(writeback_single_inode_template,
+
+	TP_PROTO(struct inode *inode,
+		 struct writeback_control *wbc,
+		 unsigned long nr_to_write
+	),
+
+	TP_ARGS(inode, wbc, nr_to_write),
+
+	TP_STRUCT__entry(
+		__array(char, name, 32)
+		__field(u64, ino)
+		__field(u64, cgroup_ino)
+		__field(unsigned long, state)
+		__field(unsigned long, dirtied_when)
+		__field(unsigned long, writeback_index)
+		__field(unsigned long, wrote)
+		__field(long, nr_to_write)
+	),
+
+	TP_fast_assign(
+		strscpy_pad(__entry->name,
+			    bdi_dev_name(inode_to_bdi(inode)), 32);
+		__entry->ino		= inode->i_ino;
+		__entry->state		= inode_state_read_once(inode);
+		__entry->dirtied_when	= inode->dirtied_when;
+		__entry->writeback_index = inode->i_mapping->writeback_index;
+		__entry->nr_to_write	= nr_to_write;
+		__entry->wrote		= nr_to_write - wbc->nr_to_write;
+		__entry->cgroup_ino	= __trace_wbc_assign_cgroup(wbc);
+	),
+
+	TP_printk("bdi %s: ino=%llu state=%s dirtied_when=%lu age=%lu "
+		  "index=%lu to_write=%ld wrote=%lu cgroup_ino=%llu",
+		  __entry->name,
+		  __entry->ino,
+		  show_inode_state(__entry->state),
+		  __entry->dirtied_when,
+		  (jiffies - __entry->dirtied_when) / HZ,
+		  __entry->writeback_index,
+		  __entry->nr_to_write,
+		  __entry->wrote,
+		  __entry->cgroup_ino
+	)
+);
+
+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,
+		 unsigned long nr_to_write),
+	TP_ARGS(inode, wbc, nr_to_write)
+);
+
+DECLARE_EVENT_CLASS(writeback_inode_template,
+	TP_PROTO(struct inode *inode),
+
+	TP_ARGS(inode),
+
+	TP_STRUCT__entry(
+		__field(	u64,	ino			)
+		__field(unsigned long,	state			)
+		__field(unsigned long, dirtied_when		)
+		__field(	dev_t,	dev			)
+		__field(	__u16, mode			)
+	),
+
+	TP_fast_assign(
+		__entry->dev	= inode->i_sb->s_dev;
+		__entry->ino	= inode->i_ino;
+		__entry->state	= inode_state_read_once(inode);
+		__entry->mode	= inode->i_mode;
+		__entry->dirtied_when = inode->dirtied_when;
+	),
+
+	TP_printk("dev %d,%d ino %llu dirtied %lu state %s mode 0%o",
+		  MAJOR(__entry->dev), MINOR(__entry->dev),
+		  __entry->ino, __entry->dirtied_when,
+		  show_inode_state(__entry->state), __entry->mode)
+);
+
+DEFINE_EVENT(writeback_inode_template, writeback_lazytime,
+	TP_PROTO(struct inode *inode),
+
+	TP_ARGS(inode)
+);
+
+DEFINE_EVENT(writeback_inode_template, writeback_dirty_inode_enqueue,
+
+	TP_PROTO(struct inode *inode),
+
+	TP_ARGS(inode)
+);
+
+/*
+ * Inode writeback list tracking.
+ */
+
+DEFINE_EVENT(writeback_inode_template, sb_mark_inode_writeback,
+	TP_PROTO(struct inode *inode),
+	TP_ARGS(inode)
+);
+
+DEFINE_EVENT(writeback_inode_template, sb_clear_inode_writeback,
+	TP_PROTO(struct inode *inode),
+	TP_ARGS(inode)
+);
+
+#endif /* _TRACE_WRITEBACK_H */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>