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

arch/x86/xen/mmu.c

+7 −0
Original line number Diff line number Diff line
@@ -70,6 +70,13 @@ 


#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



static struct {

drivers/xen/balloon.c

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



/* 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))

		nr_pages = ARRAY_SIZE(frame_list);



	spin_lock_irqsave(&balloon_lock, flags);

	spin_lock_irqsave(&xen_reservation_lock, flags);



	page = balloon_first_page();

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



 out:

	spin_unlock_irqrestore(&balloon_lock, flags);

	spin_unlock_irqrestore(&xen_reservation_lock, flags);



	return rc < 0 ? rc : rc != nr_pages;

}
@@ -299,7 +292,7 @@ static int decrease_reservation(unsigned long nr_pages) 
	kmap_flush_unused();

	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. */

	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;



	spin_unlock_irqrestore(&balloon_lock, flags);

	spin_unlock_irqrestore(&xen_reservation_lock, flags);



	return need_sleep;

}

include/xen/interface/memory.h

+8 −0
Original line number Diff line number Diff line
@@ -9,6 +9,8 @@ 
#ifndef __XEN_PUBLIC_MEMORY_H__

#define __XEN_PUBLIC_MEMORY_H__



#include <linux/spinlock.h>



/*

 * Increase or decrease the specified domain's memory reservation. Returns a

 * -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);





/*

 * 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__ */

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