From 22e2c507c301c3dbbcf91b4948b88f78842ee6c9 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Mon, 27 Jun 2005 10:55:12 +0200 Subject: [PATCH] Update cfq io scheduler to time sliced design This updates the CFQ io scheduler to the new time sliced design (cfq v3). It provides full process fairness, while giving excellent aggregate system throughput even for many competing processes. It supports io priorities, either inherited from the cpu nice value or set directly with the ioprio_get/set syscalls. The latter closely mimic set/getpriority. This import is based on my latest from -mm. Signed-off-by: Jens Axboe Signed-off-by: Linus Torvalds --- include/linux/blkdev.h | 25 +++++++++++++++++-------- 1 file changed, 17 insertions(+), 8 deletions(-) (limited to 'include/linux/blkdev.h') diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index b54a0348a890..21a8674cd149 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -54,16 +54,23 @@ struct as_io_context { struct cfq_queue; struct cfq_io_context { - void (*dtor)(struct cfq_io_context *); - void (*exit)(struct cfq_io_context *); - - struct io_context *ioc; - /* * circular list of cfq_io_contexts belonging to a process io context */ struct list_head list; struct cfq_queue *cfqq; + void *key; + + struct io_context *ioc; + + unsigned long last_end_request; + unsigned long last_queue; + unsigned long ttime_total; + unsigned long ttime_samples; + unsigned long ttime_mean; + + void (*dtor)(struct cfq_io_context *); + void (*exit)(struct cfq_io_context *); }; /* @@ -73,7 +80,9 @@ struct cfq_io_context { */ struct io_context { atomic_t refcount; - pid_t pid; + struct task_struct *task; + + int (*set_ioprio)(struct io_context *, unsigned int); /* * For request batching @@ -81,8 +90,6 @@ struct io_context { unsigned long last_waited; /* Time last woken after wait for request */ int nr_batch_requests; /* Number of requests left in the batch */ - spinlock_t lock; - struct as_io_context *aic; struct cfq_io_context *cic; }; @@ -134,6 +141,8 @@ struct request { void *elevator_private; + unsigned short ioprio; + int rq_status; /* should split this into a few status bits */ struct gendisk *rq_disk; int errors; -- cgit v1.2.3 From fb3cc4320e1fd87143683b540e459a2e20fdc9bb Mon Sep 17 00:00:00 2001 From: Nick Piggin Date: Tue, 28 Jun 2005 20:45:15 -0700 Subject: [PATCH] blk: light iocontext ops get_io_context needlessly turned off interrupts and checked for racing io context creations. Both of which aren't needed, because the io context can only be created while in process context of the current process. Also, split the function in 2. A light version, current_io_context does not elevate the reference count specifically, but can be used when in process context, because the process holds a reference itself. Signed-off-by: Nick Piggin Cc: Jens Axboe Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/blkdev.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/linux/blkdev.h') diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 21a8674cd149..0881b5cdee3d 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -96,6 +96,7 @@ struct io_context { void put_io_context(struct io_context *ioc); void exit_io_context(void); +struct io_context *current_io_context(int gfp_flags); struct io_context *get_io_context(int gfp_flags); void copy_io_context(struct io_context **pdst, struct io_context **psrc); void swap_io_context(struct io_context **ioc1, struct io_context **ioc2); -- cgit v1.2.3