Add a tracepoint for block request remapping (b0da3f0d) · Commits · 戴 / test

block/blk-core.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -34,6 +34,7 @@
		#include "blk.h"

		EXPORT_TRACEPOINT_SYMBOL_GPL(block_remap);
		EXPORT_TRACEPOINT_SYMBOL_GPL(block_rq_remap);
		EXPORT_TRACEPOINT_SYMBOL_GPL(block_bio_complete);

		static int __make_request(struct request_queue q, struct bio bio);

+1 −1

Original line number	Diff line number	Diff line
		@@ -212,7 +212,7 @@ extern struct attribute_group blk_trace_attr_group;
		# define blk_trace_startstop(q, start) (-ENOTTY)
		# define blk_trace_remove(q) (-ENOTTY)
		# define blk_add_trace_msg(q, fmt, ...) do { } while (0)
		# define blk_trace_remove_sysfs(struct device *dev) do { } while (0)
		# define blk_trace_remove_sysfs(dev) do { } while (0)
		static inline int blk_trace_init_sysfs(struct device *dev)
		{
		return 0;

+33 −0

Original line number	Diff line number	Diff line
		@@ -488,6 +488,39 @@ TRACE_EVENT(block_remap,
		(unsigned long long)__entry->old_sector)
		);

		TRACE_EVENT(block_rq_remap,

		TP_PROTO(struct request_queue q, struct request rq, dev_t dev,
		sector_t from),

		TP_ARGS(q, rq, dev, from),

		TP_STRUCT__entry(
		__field( dev_t, dev )
		__field( sector_t, sector )
		__field( unsigned int, nr_sector )
		__field( dev_t, old_dev )
		__field( sector_t, old_sector )
		__array( char, rwbs, 6 )
		),

		TP_fast_assign(
		__entry->dev = disk_devt(rq->rq_disk);
		__entry->sector = blk_rq_pos(rq);
		__entry->nr_sector = blk_rq_sectors(rq);
		__entry->old_dev = dev;
		__entry->old_sector = from;
		blk_fill_rwbs_rq(__entry->rwbs, rq);
		),

		TP_printk("%d,%d %s %llu + %u <- (%d,%d) %llu",
		MAJOR(__entry->dev), MINOR(__entry->dev), __entry->rwbs,
		(unsigned long long)__entry->sector,
		__entry->nr_sector,
		MAJOR(__entry->old_dev), MINOR(__entry->old_dev),
		(unsigned long long)__entry->old_sector)
		);

		#endif /* _TRACE_BLOCK_H */

		/* This part must be outside protection */

+34 −0

Original line number	Diff line number	Diff line
		@@ -855,6 +855,37 @@ static void blk_add_trace_remap(struct request_queue q, struct bio bio,
		sizeof(r), &r);
		}

		/**
		* blk_add_trace_rq_remap - Add a trace for a request-remap operation
		* @q: queue the io is for
		* @rq: the source request
		* @dev: target device
		* @from: source sector
		*
		* Description:
		* Device mapper remaps request to other devices.
		* Add a trace for that action.
		*
		**/
		static void blk_add_trace_rq_remap(struct request_queue *q,
		struct request *rq, dev_t dev,
		sector_t from)
		{
		struct blk_trace *bt = q->blk_trace;
		struct blk_io_trace_remap r;

		if (likely(!bt))
		return;

		r.device_from = cpu_to_be32(dev);
		r.device_to = cpu_to_be32(disk_devt(rq->rq_disk));
		r.sector_from = cpu_to_be64(from);

		__blk_add_trace(bt, blk_rq_pos(rq), blk_rq_bytes(rq),
		rq_data_dir(rq), BLK_TA_REMAP, !!rq->errors,
		sizeof(r), &r);
		}

		/**
		* blk_add_driver_data - Add binary message with driver-specific data
		* @q: queue the io is for
		@@ -922,10 +953,13 @@ static void blk_register_tracepoints(void)
		WARN_ON(ret);
		ret = register_trace_block_remap(blk_add_trace_remap);
		WARN_ON(ret);
		ret = register_trace_block_rq_remap(blk_add_trace_rq_remap);
		WARN_ON(ret);
		}

		static void blk_unregister_tracepoints(void)
		{
		unregister_trace_block_rq_remap(blk_add_trace_rq_remap);
		unregister_trace_block_remap(blk_add_trace_remap);
		unregister_trace_block_split(blk_add_trace_split);
		unregister_trace_block_unplug_io(blk_add_trace_unplug_io);