Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 9659f811 authored by Mike Snitzer's avatar Mike Snitzer
Browse files

dm mpath: push path selector locking down to path selectors 



Proper locking of the lists used by the path selectors should be handled
within the selectors (relying on dm-mpath.c code's use of the m->lock
spinlock was reckless).

Signed-off-by: default avatarMike Snitzer <snitzer@redhat.com>
parent 21136f89

drivers/md/dm-queue-length.c

+20 −3
Original line number Original line Diff line number Diff line
@@ -29,6 +29,7 @@ 
struct selector {

struct selector {

	struct list_head	valid_paths;

	struct list_head	valid_paths;

	struct list_head	failed_paths;

	struct list_head	failed_paths;

	spinlock_t lock;

};

};





struct path_info {

struct path_info {
@@ -45,6 +46,7 @@ static struct selector *alloc_selector(void) 
	if (s) {

	if (s) {

		INIT_LIST_HEAD(&s->valid_paths);

		INIT_LIST_HEAD(&s->valid_paths);

		INIT_LIST_HEAD(&s->failed_paths);

		INIT_LIST_HEAD(&s->failed_paths);

		spin_lock_init(&s->lock);

	}

	}





	return s;

	return s;
@@ -113,6 +115,7 @@ static int ql_add_path(struct path_selector *ps, struct dm_path *path, 
	struct path_info *pi;

	struct path_info *pi;

	unsigned repeat_count = QL_MIN_IO;

	unsigned repeat_count = QL_MIN_IO;

	char dummy;

	char dummy;

	unsigned long flags;





	/*

	/*

	 * Arguments: [<repeat_count>]

	 * Arguments: [<repeat_count>]
@@ -147,7 +150,9 @@ static int ql_add_path(struct path_selector *ps, struct dm_path *path, 




	path->pscontext = pi;

	path->pscontext = pi;





	spin_lock_irqsave(&s->lock, flags);

	list_add_tail(&pi->list, &s->valid_paths);

	list_add_tail(&pi->list, &s->valid_paths);

	spin_unlock_irqrestore(&s->lock, flags);





	return 0;

	return 0;

}

}
@@ -156,16 +161,22 @@ static void ql_fail_path(struct path_selector *ps, struct dm_path *path) 
{

{

	struct selector *s = ps->context;

	struct selector *s = ps->context;

	struct path_info *pi = path->pscontext;

	struct path_info *pi = path->pscontext;

	unsigned long flags;





	spin_lock_irqsave(&s->lock, flags);

	list_move(&pi->list, &s->failed_paths);

	list_move(&pi->list, &s->failed_paths);

	spin_unlock_irqrestore(&s->lock, flags);

}

}





static int ql_reinstate_path(struct path_selector *ps, struct dm_path *path)

static int ql_reinstate_path(struct path_selector *ps, struct dm_path *path)

{

{

	struct selector *s = ps->context;

	struct selector *s = ps->context;

	struct path_info *pi = path->pscontext;

	struct path_info *pi = path->pscontext;

	unsigned long flags;





	spin_lock_irqsave(&s->lock, flags);

	list_move_tail(&pi->list, &s->valid_paths);

	list_move_tail(&pi->list, &s->valid_paths);

	spin_unlock_irqrestore(&s->lock, flags);





	return 0;

	return 0;

}

}
@@ -178,9 +189,12 @@ static struct dm_path *ql_select_path(struct path_selector *ps, 
{

{

	struct selector *s = ps->context;

	struct selector *s = ps->context;

	struct path_info *pi = NULL, *best = NULL;

	struct path_info *pi = NULL, *best = NULL;

	struct dm_path *ret = NULL;

	unsigned long flags;





	spin_lock_irqsave(&s->lock, flags);

	if (list_empty(&s->valid_paths))

	if (list_empty(&s->valid_paths))

		return NULL;

		goto out;





	/* Change preferred (first in list) path to evenly balance. */

	/* Change preferred (first in list) path to evenly balance. */

	list_move_tail(s->valid_paths.next, &s->valid_paths);

	list_move_tail(s->valid_paths.next, &s->valid_paths);
@@ -195,11 +209,14 @@ static struct dm_path *ql_select_path(struct path_selector *ps, 
	}

	}





	if (!best)

	if (!best)

		return NULL;

		goto out;





	*repeat_count = best->repeat_count;

	*repeat_count = best->repeat_count;





	return best->path;

	ret = best->path;

out:

	spin_unlock_irqrestore(&s->lock, flags);

	return ret;

}

}





static int ql_start_io(struct path_selector *ps, struct dm_path *path,

static int ql_start_io(struct path_selector *ps, struct dm_path *path,

drivers/md/dm-round-robin.c

+19 −5
Original line number Original line Diff line number Diff line
@@ -46,6 +46,7 @@ static void free_paths(struct list_head *paths) 
struct selector {

struct selector {

	struct list_head valid_paths;

	struct list_head valid_paths;

	struct list_head invalid_paths;

	struct list_head invalid_paths;

	spinlock_t lock;

};

};





static struct selector *alloc_selector(void)

static struct selector *alloc_selector(void)
@@ -55,6 +56,7 @@ static struct selector *alloc_selector(void) 
	if (s) {

	if (s) {

		INIT_LIST_HEAD(&s->valid_paths);

		INIT_LIST_HEAD(&s->valid_paths);

		INIT_LIST_HEAD(&s->invalid_paths);

		INIT_LIST_HEAD(&s->invalid_paths);

		spin_lock_init(&s->lock);

	}

	}





	return s;

	return s;
@@ -74,7 +76,7 @@ static int rr_create(struct path_selector *ps, unsigned argc, char **argv) 




static void rr_destroy(struct path_selector *ps)

static void rr_destroy(struct path_selector *ps)

{

{

	struct selector *s = (struct selector *) ps->context;

	struct selector *s = ps->context;





	free_paths(&s->valid_paths);

	free_paths(&s->valid_paths);

	free_paths(&s->invalid_paths);

	free_paths(&s->invalid_paths);
@@ -111,10 +113,11 @@ static int rr_status(struct path_selector *ps, struct dm_path *path, 
static int rr_add_path(struct path_selector *ps, struct dm_path *path,

static int rr_add_path(struct path_selector *ps, struct dm_path *path,

		       int argc, char **argv, char **error)

		       int argc, char **argv, char **error)

{

{

	struct selector *s = (struct selector *) ps->context;

	struct selector *s = ps->context;

	struct path_info *pi;

	struct path_info *pi;

	unsigned repeat_count = RR_MIN_IO;

	unsigned repeat_count = RR_MIN_IO;

	char dummy;

	char dummy;

	unsigned long flags;





	if (argc > 1) {

	if (argc > 1) {

		*error = "round-robin ps: incorrect number of arguments";

		*error = "round-robin ps: incorrect number of arguments";
@@ -144,25 +147,33 @@ static int rr_add_path(struct path_selector *ps, struct dm_path *path, 




	path->pscontext = pi;

	path->pscontext = pi;





	spin_lock_irqsave(&s->lock, flags);

	list_add_tail(&pi->list, &s->valid_paths);

	list_add_tail(&pi->list, &s->valid_paths);

	spin_unlock_irqrestore(&s->lock, flags);





	return 0;

	return 0;

}

}





static void rr_fail_path(struct path_selector *ps, struct dm_path *p)

static void rr_fail_path(struct path_selector *ps, struct dm_path *p)

{

{

	struct selector *s = (struct selector *) ps->context;

	unsigned long flags;

	struct selector *s = ps->context;

	struct path_info *pi = p->pscontext;

	struct path_info *pi = p->pscontext;





	spin_lock_irqsave(&s->lock, flags);

	list_move(&pi->list, &s->invalid_paths);

	list_move(&pi->list, &s->invalid_paths);

	spin_unlock_irqrestore(&s->lock, flags);

}

}





static int rr_reinstate_path(struct path_selector *ps, struct dm_path *p)

static int rr_reinstate_path(struct path_selector *ps, struct dm_path *p)

{

{

	struct selector *s = (struct selector *) ps->context;

	unsigned long flags;

	struct selector *s = ps->context;

	struct path_info *pi = p->pscontext;

	struct path_info *pi = p->pscontext;





	spin_lock_irqsave(&s->lock, flags);

	list_move(&pi->list, &s->valid_paths);

	list_move(&pi->list, &s->valid_paths);

	spin_unlock_irqrestore(&s->lock, flags);





	return 0;

	return 0;

}

}
@@ -170,14 +181,17 @@ static int rr_reinstate_path(struct path_selector *ps, struct dm_path *p) 
static struct dm_path *rr_select_path(struct path_selector *ps,

static struct dm_path *rr_select_path(struct path_selector *ps,

				      unsigned *repeat_count, size_t nr_bytes)

				      unsigned *repeat_count, size_t nr_bytes)

{

{

	struct selector *s = (struct selector *) ps->context;

	unsigned long flags;

	struct selector *s = ps->context;

	struct path_info *pi = NULL;

	struct path_info *pi = NULL;





	spin_lock_irqsave(&s->lock, flags);

	if (!list_empty(&s->valid_paths)) {

	if (!list_empty(&s->valid_paths)) {

		pi = list_entry(s->valid_paths.next, struct path_info, list);

		pi = list_entry(s->valid_paths.next, struct path_info, list);

		list_move_tail(&pi->list, &s->valid_paths);

		list_move_tail(&pi->list, &s->valid_paths);

		*repeat_count = pi->repeat_count;

		*repeat_count = pi->repeat_count;

	}

	}

	spin_unlock_irqrestore(&s->lock, flags);





	return pi ? pi->path : NULL;

	return pi ? pi->path : NULL;

}

}

drivers/md/dm-service-time.c

+20 −3
Original line number Original line Diff line number Diff line
@@ -24,6 +24,7 @@ 
struct selector {

struct selector {

	struct list_head valid_paths;

	struct list_head valid_paths;

	struct list_head failed_paths;

	struct list_head failed_paths;

	spinlock_t lock;

};

};





struct path_info {

struct path_info {
@@ -41,6 +42,7 @@ static struct selector *alloc_selector(void) 
	if (s) {

	if (s) {

		INIT_LIST_HEAD(&s->valid_paths);

		INIT_LIST_HEAD(&s->valid_paths);

		INIT_LIST_HEAD(&s->failed_paths);

		INIT_LIST_HEAD(&s->failed_paths);

		spin_lock_init(&s->lock);

	}

	}





	return s;

	return s;
@@ -111,6 +113,7 @@ static int st_add_path(struct path_selector *ps, struct dm_path *path, 
	unsigned repeat_count = ST_MIN_IO;

	unsigned repeat_count = ST_MIN_IO;

	unsigned relative_throughput = 1;

	unsigned relative_throughput = 1;

	char dummy;

	char dummy;

	unsigned long flags;





	/*

	/*

	 * Arguments: [<repeat_count> [<relative_throughput>]]

	 * Arguments: [<repeat_count> [<relative_throughput>]]
@@ -160,7 +163,9 @@ static int st_add_path(struct path_selector *ps, struct dm_path *path, 




	path->pscontext = pi;

	path->pscontext = pi;





	spin_lock_irqsave(&s->lock, flags);

	list_add_tail(&pi->list, &s->valid_paths);

	list_add_tail(&pi->list, &s->valid_paths);

	spin_unlock_irqrestore(&s->lock, flags);





	return 0;

	return 0;

}

}
@@ -169,16 +174,22 @@ static void st_fail_path(struct path_selector *ps, struct dm_path *path) 
{

{

	struct selector *s = ps->context;

	struct selector *s = ps->context;

	struct path_info *pi = path->pscontext;

	struct path_info *pi = path->pscontext;

	unsigned long flags;





	spin_lock_irqsave(&s->lock, flags);

	list_move(&pi->list, &s->failed_paths);

	list_move(&pi->list, &s->failed_paths);

	spin_unlock_irqrestore(&s->lock, flags);

}

}





static int st_reinstate_path(struct path_selector *ps, struct dm_path *path)

static int st_reinstate_path(struct path_selector *ps, struct dm_path *path)

{

{

	struct selector *s = ps->context;

	struct selector *s = ps->context;

	struct path_info *pi = path->pscontext;

	struct path_info *pi = path->pscontext;

	unsigned long flags;





	spin_lock_irqsave(&s->lock, flags);

	list_move_tail(&pi->list, &s->valid_paths);

	list_move_tail(&pi->list, &s->valid_paths);

	spin_unlock_irqrestore(&s->lock, flags);





	return 0;

	return 0;

}

}
@@ -265,9 +276,12 @@ static struct dm_path *st_select_path(struct path_selector *ps, 
{

{

	struct selector *s = ps->context;

	struct selector *s = ps->context;

	struct path_info *pi = NULL, *best = NULL;

	struct path_info *pi = NULL, *best = NULL;

	struct dm_path *ret = NULL;

	unsigned long flags;





	spin_lock_irqsave(&s->lock, flags);

	if (list_empty(&s->valid_paths))

	if (list_empty(&s->valid_paths))

		return NULL;

		goto out;





	/* Change preferred (first in list) path to evenly balance. */

	/* Change preferred (first in list) path to evenly balance. */

	list_move_tail(s->valid_paths.next, &s->valid_paths);

	list_move_tail(s->valid_paths.next, &s->valid_paths);
@@ -277,11 +291,14 @@ static struct dm_path *st_select_path(struct path_selector *ps, 
			best = pi;

			best = pi;





	if (!best)

	if (!best)

		return NULL;

		goto out;





	*repeat_count = best->repeat_count;

	*repeat_count = best->repeat_count;





	return best->path;

	ret = best->path;

out:

	spin_unlock_irqrestore(&s->lock, flags);

	return ret;

}

}





static int st_start_io(struct path_selector *ps, struct dm_path *path,

static int st_start_io(struct path_selector *ps, struct dm_path *path,