Commit 19001c8c authored by Alex Nixon's avatar Alex Nixon Committed by Konrad Rzeszutek Wilk
Browse files

xen: Rename the balloon lock



* xen_create_contiguous_region needs access to the balloon lock to
  ensure memory doesn't change under its feet, so expose the balloon
  lock
* Change the name of the lock to xen_reservation_lock, to imply it's
  now less-specific usage.

[ Impact: cleanup ]

Signed-off-by: default avatarAlex Nixon <alex.nixon@citrix.com>
Signed-off-by: default avatarJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: default avatarKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
parent 7347b408
Loading
Loading
Loading
Loading
+7 −0
Original line number Original line Diff line number Diff line
@@ -70,6 +70,13 @@


#define MMU_UPDATE_HISTO	30
#define MMU_UPDATE_HISTO	30


/*
 * Protects atomic reservation decrease/increase against concurrent increases.
 * Also protects non-atomic updates of current_pages and driver_pages, and
 * balloon lists.
 */
DEFINE_SPINLOCK(xen_reservation_lock);

#ifdef CONFIG_XEN_DEBUG_FS
#ifdef CONFIG_XEN_DEBUG_FS


static struct {
static struct {
+4 −11
Original line number Original line Diff line number Diff line
@@ -85,13 +85,6 @@ static struct sys_device balloon_sysdev;


static int register_balloon(struct sys_device *sysdev);
static int register_balloon(struct sys_device *sysdev);


/*
 * Protects atomic reservation decrease/increase against concurrent increases.
 * Also protects non-atomic updates of current_pages and driver_pages, and
 * balloon lists.
 */
static DEFINE_SPINLOCK(balloon_lock);

static struct balloon_stats balloon_stats;
static struct balloon_stats balloon_stats;


/* We increase/decrease in batches which fit in a page */
/* We increase/decrease in batches which fit in a page */
@@ -210,7 +203,7 @@ static int increase_reservation(unsigned long nr_pages)
	if (nr_pages > ARRAY_SIZE(frame_list))
	if (nr_pages > ARRAY_SIZE(frame_list))
		nr_pages = ARRAY_SIZE(frame_list);
		nr_pages = ARRAY_SIZE(frame_list);


	spin_lock_irqsave(&balloon_lock, flags);
	spin_lock_irqsave(&xen_reservation_lock, flags);


	page = balloon_first_page();
	page = balloon_first_page();
	for (i = 0; i < nr_pages; i++) {
	for (i = 0; i < nr_pages; i++) {
@@ -254,7 +247,7 @@ static int increase_reservation(unsigned long nr_pages)
	balloon_stats.current_pages += rc;
	balloon_stats.current_pages += rc;


 out:
 out:
	spin_unlock_irqrestore(&balloon_lock, flags);
	spin_unlock_irqrestore(&xen_reservation_lock, flags);


	return rc < 0 ? rc : rc != nr_pages;
	return rc < 0 ? rc : rc != nr_pages;
}
}
@@ -299,7 +292,7 @@ static int decrease_reservation(unsigned long nr_pages)
	kmap_flush_unused();
	kmap_flush_unused();
	flush_tlb_all();
	flush_tlb_all();


	spin_lock_irqsave(&balloon_lock, flags);
	spin_lock_irqsave(&xen_reservation_lock, flags);


	/* No more mappings: invalidate P2M and add to balloon. */
	/* No more mappings: invalidate P2M and add to balloon. */
	for (i = 0; i < nr_pages; i++) {
	for (i = 0; i < nr_pages; i++) {
@@ -315,7 +308,7 @@ static int decrease_reservation(unsigned long nr_pages)


	balloon_stats.current_pages -= nr_pages;
	balloon_stats.current_pages -= nr_pages;


	spin_unlock_irqrestore(&balloon_lock, flags);
	spin_unlock_irqrestore(&xen_reservation_lock, flags);


	return need_sleep;
	return need_sleep;
}
}
+8 −0
Original line number Original line Diff line number Diff line
@@ -9,6 +9,8 @@
#ifndef __XEN_PUBLIC_MEMORY_H__
#ifndef __XEN_PUBLIC_MEMORY_H__
#define __XEN_PUBLIC_MEMORY_H__
#define __XEN_PUBLIC_MEMORY_H__


#include <linux/spinlock.h>

/*
/*
 * Increase or decrease the specified domain's memory reservation. Returns a
 * Increase or decrease the specified domain's memory reservation. Returns a
 * -ve errcode on failure, or the # extents successfully allocated or freed.
 * -ve errcode on failure, or the # extents successfully allocated or freed.
@@ -142,4 +144,10 @@ struct xen_translate_gpfn_list {
};
};
DEFINE_GUEST_HANDLE_STRUCT(xen_translate_gpfn_list);
DEFINE_GUEST_HANDLE_STRUCT(xen_translate_gpfn_list);



/*
 * Prevent the balloon driver from changing the memory reservation
 * during a driver critical region.
 */
extern spinlock_t xen_reservation_lock;
#endif /* __XEN_PUBLIC_MEMORY_H__ */
#endif /* __XEN_PUBLIC_MEMORY_H__ */