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Commit 221d4684 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-lguest 

* 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-lguest:
  lguest: tidy up documentation
  kernel/futex.c: make 3 functions static
  unexport access_process_vm
  lguest: make async_hcall() static
parents 4d20826f 633872b9

arch/x86/lguest/boot.c

+34 −35
Original line number Diff line number Diff line
@@ -93,38 +93,7 @@ struct lguest_data lguest_data = { 
};

static cycle_t clock_base;



/*G:035 Notice the lazy_hcall() above, rather than hcall().  This is our first

 * real optimization trick!

 *

 * When lazy_mode is set, it means we're allowed to defer all hypercalls and do

 * them as a batch when lazy_mode is eventually turned off.  Because hypercalls

 * are reasonably expensive, batching them up makes sense.  For example, a

 * large munmap might update dozens of page table entries: that code calls

 * paravirt_enter_lazy_mmu(), does the dozen updates, then calls

 * lguest_leave_lazy_mode().

 *

 * So, when we're in lazy mode, we call async_hypercall() to store the call for

 * future processing.  When lazy mode is turned off we issue a hypercall to

 * flush the stored calls.

 */

static void lguest_leave_lazy_mode(void)

{

	paravirt_leave_lazy(paravirt_get_lazy_mode());

	hcall(LHCALL_FLUSH_ASYNC, 0, 0, 0);

}



static void lazy_hcall(unsigned long call,

		       unsigned long arg1,

		       unsigned long arg2,

		       unsigned long arg3)

{

	if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_NONE)

		hcall(call, arg1, arg2, arg3);

	else

		async_hcall(call, arg1, arg2, arg3);

}



/* async_hcall() is pretty simple: I'm quite proud of it really.  We have a

/*G:037 async_hcall() is pretty simple: I'm quite proud of it really.  We have a

 * ring buffer of stored hypercalls which the Host will run though next time we

 * do a normal hypercall.  Each entry in the ring has 4 slots for the hypercall

 * arguments, and a "hcall_status" word which is 0 if the call is ready to go,
@@ -134,8 +103,8 @@ static void lazy_hcall(unsigned long call, 
 * full and we just make the hypercall directly.  This has the nice side

 * effect of causing the Host to run all the stored calls in the ring buffer

 * which empties it for next time! */

void async_hcall(unsigned long call,

		 unsigned long arg1, unsigned long arg2, unsigned long arg3)

static void async_hcall(unsigned long call, unsigned long arg1,

			unsigned long arg2, unsigned long arg3)

{

	/* Note: This code assumes we're uniprocessor. */

	static unsigned int next_call;
@@ -161,7 +130,37 @@ void async_hcall(unsigned long call, 
	}

	local_irq_restore(flags);

}

/*:*/



/*G:035 Notice the lazy_hcall() above, rather than hcall().  This is our first

 * real optimization trick!

 *

 * When lazy_mode is set, it means we're allowed to defer all hypercalls and do

 * them as a batch when lazy_mode is eventually turned off.  Because hypercalls

 * are reasonably expensive, batching them up makes sense.  For example, a

 * large munmap might update dozens of page table entries: that code calls

 * paravirt_enter_lazy_mmu(), does the dozen updates, then calls

 * lguest_leave_lazy_mode().

 *

 * So, when we're in lazy mode, we call async_hcall() to store the call for

 * future processing. */

static void lazy_hcall(unsigned long call,

		       unsigned long arg1,

		       unsigned long arg2,

		       unsigned long arg3)

{

	if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_NONE)

		hcall(call, arg1, arg2, arg3);

	else

		async_hcall(call, arg1, arg2, arg3);

}



/* When lazy mode is turned off reset the per-cpu lazy mode variable and then

 * issue a hypercall to flush any stored calls. */

static void lguest_leave_lazy_mode(void)

{

	paravirt_leave_lazy(paravirt_get_lazy_mode());

	hcall(LHCALL_FLUSH_ASYNC, 0, 0, 0);

}



/*G:033

 * After that diversion we return to our first native-instruction

include/asm-x86/lguest_hcall.h

+0 −3
Original line number Diff line number Diff line
@@ -54,9 +54,6 @@ hcall(unsigned long call, 
}

/*:*/



void async_hcall(unsigned long call,

		 unsigned long arg1, unsigned long arg2, unsigned long arg3);



/* Can't use our min() macro here: needs to be a constant */

#define LGUEST_IRQS (NR_IRQS < 32 ? NR_IRQS: 32)

include/linux/futex.h

+0 −4
Original line number Diff line number Diff line
@@ -149,10 +149,6 @@ union futex_key { 
		int offset;

	} both;

};

int get_futex_key(u32 __user *uaddr, struct rw_semaphore *shared,

		  union futex_key *key);

void get_futex_key_refs(union futex_key *key);

void drop_futex_key_refs(union futex_key *key);



#ifdef CONFIG_FUTEX

extern void exit_robust_list(struct task_struct *curr);

kernel/futex.c

+4 −7
Original line number Diff line number Diff line
@@ -181,7 +181,7 @@ static inline int match_futex(union futex_key *key1, union futex_key *key2) 
 * For other futexes, it points to &current->mm->mmap_sem and

 * caller must have taken the reader lock. but NOT any spinlocks.

 */

int get_futex_key(u32 __user *uaddr, struct rw_semaphore *fshared,

static int get_futex_key(u32 __user *uaddr, struct rw_semaphore *fshared,

			 union futex_key *key)

{

	unsigned long address = (unsigned long)uaddr;
@@ -268,14 +268,13 @@ int get_futex_key(u32 __user *uaddr, struct rw_semaphore *fshared, 
	}

	return err;

}

EXPORT_SYMBOL_GPL(get_futex_key);



/*

 * Take a reference to the resource addressed by a key.

 * Can be called while holding spinlocks.

 *

 */

inline void get_futex_key_refs(union futex_key *key)

static void get_futex_key_refs(union futex_key *key)

{

	if (key->both.ptr == 0)

		return;
@@ -288,13 +287,12 @@ inline void get_futex_key_refs(union futex_key *key) 
			break;

	}

}

EXPORT_SYMBOL_GPL(get_futex_key_refs);



/*

 * Drop a reference to the resource addressed by a key.

 * The hash bucket spinlock must not be held.

 */

void drop_futex_key_refs(union futex_key *key)

static void drop_futex_key_refs(union futex_key *key)

{

	if (!key->both.ptr)

		return;
@@ -307,7 +305,6 @@ void drop_futex_key_refs(union futex_key *key) 
			break;

	}

}

EXPORT_SYMBOL_GPL(drop_futex_key_refs);



static u32 cmpxchg_futex_value_locked(u32 __user *uaddr, u32 uval, u32 newval)

{

mm/memory.c

+0 −1
Original line number Diff line number Diff line
@@ -2748,4 +2748,3 @@ int access_process_vm(struct task_struct *tsk, unsigned long addr, void *buf, in 


	return buf - old_buf;

}
 
EXPORT_SYMBOL_GPL(access_process_vm);