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

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* '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
This commit is contained in:
Linus Torvalds
2007-11-05 11:39:00 -08:00
parent 4d20826ffb 633872b980
commit 221d46841b
5 changed files with 38 additions and 50 deletions
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69
arch/x86/lguest/boot.c
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@ -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