exec: replace leaf with skip

In preparation for dynamic radix tree depth support, rename is_leaf
field to skip, telling us how many bits to skip to next level.
Set to 0 for leaf.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This commit is contained in:
Michael S. Tsirkin 2013-11-11 14:42:43 +02:00
parent 03f4995781
commit 9736e55b78

17
exec.c
View File

@ -83,8 +83,9 @@ int use_icount;
typedef struct PhysPageEntry PhysPageEntry; typedef struct PhysPageEntry PhysPageEntry;
struct PhysPageEntry { struct PhysPageEntry {
uint16_t is_leaf : 1; /* How many bits skip to next level (in units of L2_SIZE). 0 for a leaf. */
/* index into phys_sections (is_leaf) or phys_map_nodes (!is_leaf) */ uint16_t skip : 1;
/* index into phys_sections (!skip) or phys_map_nodes (skip) */
uint16_t ptr : 15; uint16_t ptr : 15;
}; };
@ -164,7 +165,7 @@ static uint16_t phys_map_node_alloc(void)
assert(ret != PHYS_MAP_NODE_NIL); assert(ret != PHYS_MAP_NODE_NIL);
assert(ret != next_map.nodes_nb_alloc); assert(ret != next_map.nodes_nb_alloc);
for (i = 0; i < P_L2_SIZE; ++i) { for (i = 0; i < P_L2_SIZE; ++i) {
next_map.nodes[ret][i].is_leaf = 0; next_map.nodes[ret][i].skip = 1;
next_map.nodes[ret][i].ptr = PHYS_MAP_NODE_NIL; next_map.nodes[ret][i].ptr = PHYS_MAP_NODE_NIL;
} }
return ret; return ret;
@ -178,12 +179,12 @@ static void phys_page_set_level(PhysPageEntry *lp, hwaddr *index,
int i; int i;
hwaddr step = (hwaddr)1 << (level * P_L2_BITS); hwaddr step = (hwaddr)1 << (level * P_L2_BITS);
if (!lp->is_leaf && lp->ptr == PHYS_MAP_NODE_NIL) { if (lp->skip && lp->ptr == PHYS_MAP_NODE_NIL) {
lp->ptr = phys_map_node_alloc(); lp->ptr = phys_map_node_alloc();
p = next_map.nodes[lp->ptr]; p = next_map.nodes[lp->ptr];
if (level == 0) { if (level == 0) {
for (i = 0; i < P_L2_SIZE; i++) { for (i = 0; i < P_L2_SIZE; i++) {
p[i].is_leaf = 1; p[i].skip = 0;
p[i].ptr = PHYS_SECTION_UNASSIGNED; p[i].ptr = PHYS_SECTION_UNASSIGNED;
} }
} }
@ -194,7 +195,7 @@ static void phys_page_set_level(PhysPageEntry *lp, hwaddr *index,
while (*nb && lp < &p[P_L2_SIZE]) { while (*nb && lp < &p[P_L2_SIZE]) {
if ((*index & (step - 1)) == 0 && *nb >= step) { if ((*index & (step - 1)) == 0 && *nb >= step) {
lp->is_leaf = true; lp->skip = 0;
lp->ptr = leaf; lp->ptr = leaf;
*index += step; *index += step;
*nb -= step; *nb -= step;
@ -221,7 +222,7 @@ static MemoryRegionSection *phys_page_find(PhysPageEntry lp, hwaddr index,
PhysPageEntry *p; PhysPageEntry *p;
int i; int i;
for (i = P_L2_LEVELS - 1; i >= 0 && !lp.is_leaf; i--) { for (i = P_L2_LEVELS; lp.skip && (i -= lp.skip) >= 0;) {
if (lp.ptr == PHYS_MAP_NODE_NIL) { if (lp.ptr == PHYS_MAP_NODE_NIL) {
return &sections[PHYS_SECTION_UNASSIGNED]; return &sections[PHYS_SECTION_UNASSIGNED];
} }
@ -1681,7 +1682,7 @@ static void mem_begin(MemoryListener *listener)
AddressSpace *as = container_of(listener, AddressSpace, dispatch_listener); AddressSpace *as = container_of(listener, AddressSpace, dispatch_listener);
AddressSpaceDispatch *d = g_new(AddressSpaceDispatch, 1); AddressSpaceDispatch *d = g_new(AddressSpaceDispatch, 1);
d->phys_map = (PhysPageEntry) { .ptr = PHYS_MAP_NODE_NIL, .is_leaf = 0 }; d->phys_map = (PhysPageEntry) { .ptr = PHYS_MAP_NODE_NIL, .skip = 1 };
d->as = as; d->as = as;
as->next_dispatch = d; as->next_dispatch = d;
} }