On Tue, 2013-12-10 at 13:49 +0200, Michael S. Tsirkin wrote:
> On Sun, Dec 01, 2013 at 02:02:23PM +0200, Marcel Apfelbaum wrote:
> > Every address space has its own nodes and sections, but
> > it uses the same global arrays of nodes/section.
> >
> > This limits the number of devices that can be attached
> > to the guest to 20-30 devices. It happens because:
> > - The sections array is limited to 2^12 entries.
> > - The main memory has at least 100 sections.
> > - Each device address space is actually an alias to
> > main memory, multiplying its number of nodes/sections.
> >
> > Remove the limitation by using separate arrays of
> > nodes and sections for each address space.
> >
> > Signed-off-by: Marcel Apfelbaum <marce...@redhat.com>
>
> I applied this on the pci tree, pls verify it's applied correctly.
I saw one issue that can be solved by:
diff --git a/exec.c b/exec.c
index 07992e9..00526d1 100644
--- a/exec.c
+++ b/exec.c
@@ -269,7 +269,7 @@ static void phys_page_compact_all(AddressSpaceDispatch *d,
int nodes_nb)
DECLARE_BITMAP(compacted, nodes_nb);
if (d->phys_map.skip) {
- phys_page_compact(&d->phys_map, d->nodes, compacted);
+ phys_page_compact(&d->phys_map, d->map.nodes, compacted);
}
}
Beside this it looks OK, the branch does not compile and I couldn't look into
it more...
Can you please also merge my other patch
"memory.c: bugfix - ref counting mismatch in memory_region_find" ?
It is already reviewed,
Thanks!
Marcel
>
> > ---
> > exec.c | 151
> > ++++++++++++++++++++++++++++-------------------------------------
> > 1 file changed, 64 insertions(+), 87 deletions(-)
> >
> > diff --git a/exec.c b/exec.c
> > index 95c4356..db2844c 100644
> > --- a/exec.c
> > +++ b/exec.c
> > @@ -90,13 +90,21 @@ struct PhysPageEntry {
> >
> > typedef PhysPageEntry Node[L2_SIZE];
> >
> > +typedef struct PhysPageMap {
> > + unsigned sections_nb;
> > + unsigned sections_nb_alloc;
> > + unsigned nodes_nb;
> > + unsigned nodes_nb_alloc;
> > + Node *nodes;
> > + MemoryRegionSection *sections;
> > +} PhysPageMap;
> > +
> > struct AddressSpaceDispatch {
> > /* This is a multi-level map on the physical address space.
> > * The bottom level has pointers to MemoryRegionSections.
> > */
> > PhysPageEntry phys_map;
> > - Node *nodes;
> > - MemoryRegionSection *sections;
> > + PhysPageMap map;
> > AddressSpace *as;
> > };
> >
> > @@ -113,18 +121,6 @@ typedef struct subpage_t {
> > #define PHYS_SECTION_ROM 2
> > #define PHYS_SECTION_WATCH 3
> >
> > -typedef struct PhysPageMap {
> > - unsigned sections_nb;
> > - unsigned sections_nb_alloc;
> > - unsigned nodes_nb;
> > - unsigned nodes_nb_alloc;
> > - Node *nodes;
> > - MemoryRegionSection *sections;
> > -} PhysPageMap;
> > -
> > -static PhysPageMap *prev_map;
> > -static PhysPageMap next_map;
> > -
> > #define PHYS_MAP_NODE_NIL (((uint16_t)~0) >> 1)
> >
> > static void io_mem_init(void);
> > @@ -135,35 +131,32 @@ static MemoryRegion io_mem_watch;
> >
> > #if !defined(CONFIG_USER_ONLY)
> >
> > -static void phys_map_node_reserve(unsigned nodes)
> > +static void phys_map_node_reserve(PhysPageMap *map, unsigned nodes)
> > {
> > - if (next_map.nodes_nb + nodes > next_map.nodes_nb_alloc) {
> > - next_map.nodes_nb_alloc = MAX(next_map.nodes_nb_alloc * 2,
> > - 16);
> > - next_map.nodes_nb_alloc = MAX(next_map.nodes_nb_alloc,
> > - next_map.nodes_nb + nodes);
> > - next_map.nodes = g_renew(Node, next_map.nodes,
> > - next_map.nodes_nb_alloc);
> > + if (map->nodes_nb + nodes > map->nodes_nb_alloc) {
> > + map->nodes_nb_alloc = MAX(map->nodes_nb_alloc * 2, 16);
> > + map->nodes_nb_alloc = MAX(map->nodes_nb_alloc, map->nodes_nb +
> > nodes);
> > + map->nodes = g_renew(Node, map->nodes, map->nodes_nb_alloc);
> > }
> > }
> >
> > -static uint16_t phys_map_node_alloc(void)
> > +static uint16_t phys_map_node_alloc(PhysPageMap *map)
> > {
> > unsigned i;
> > uint16_t ret;
> >
> > - ret = next_map.nodes_nb++;
> > + ret = map->nodes_nb++;
> > assert(ret != PHYS_MAP_NODE_NIL);
> > - assert(ret != next_map.nodes_nb_alloc);
> > + assert(ret != map->nodes_nb_alloc);
> > for (i = 0; i < L2_SIZE; ++i) {
> > - next_map.nodes[ret][i].is_leaf = 0;
> > - next_map.nodes[ret][i].ptr = PHYS_MAP_NODE_NIL;
> > + map->nodes[ret][i].is_leaf = 0;
> > + map->nodes[ret][i].ptr = PHYS_MAP_NODE_NIL;
> > }
> > return ret;
> > }
> >
> > -static void phys_page_set_level(PhysPageEntry *lp, hwaddr *index,
> > - hwaddr *nb, uint16_t leaf,
> > +static void phys_page_set_level(PhysPageMap *map, PhysPageEntry *lp,
> > + hwaddr *index, hwaddr *nb, uint16_t leaf,
> > int level)
> > {
> > PhysPageEntry *p;
> > @@ -171,8 +164,8 @@ static void phys_page_set_level(PhysPageEntry *lp,
> > hwaddr *index,
> > hwaddr step = (hwaddr)1 << (level * L2_BITS);
> >
> > if (!lp->is_leaf && lp->ptr == PHYS_MAP_NODE_NIL) {
> > - lp->ptr = phys_map_node_alloc();
> > - p = next_map.nodes[lp->ptr];
> > + lp->ptr = phys_map_node_alloc(map);
> > + p = map->nodes[lp->ptr];
> > if (level == 0) {
> > for (i = 0; i < L2_SIZE; i++) {
> > p[i].is_leaf = 1;
> > @@ -180,7 +173,7 @@ static void phys_page_set_level(PhysPageEntry *lp,
> > hwaddr *index,
> > }
> > }
> > } else {
> > - p = next_map.nodes[lp->ptr];
> > + p = map->nodes[lp->ptr];
> > }
> > lp = &p[(*index >> (level * L2_BITS)) & (L2_SIZE - 1)];
> >
> > @@ -191,7 +184,7 @@ static void phys_page_set_level(PhysPageEntry *lp,
> > hwaddr *index,
> > *index += step;
> > *nb -= step;
> > } else {
> > - phys_page_set_level(lp, index, nb, leaf, level - 1);
> > + phys_page_set_level(map, lp, index, nb, leaf, level - 1);
> > }
> > ++lp;
> > }
> > @@ -202,9 +195,9 @@ static void phys_page_set(AddressSpaceDispatch *d,
> > uint16_t leaf)
> > {
> > /* Wildly overreserve - it doesn't matter much. */
> > - phys_map_node_reserve(3 * P_L2_LEVELS);
> > + phys_map_node_reserve(&d->map, 3 * P_L2_LEVELS);
> >
> > - phys_page_set_level(&d->phys_map, &index, &nb, leaf, P_L2_LEVELS - 1);
> > + phys_page_set_level(&d->map, &d->phys_map, &index, &nb, leaf,
> > P_L2_LEVELS - 1);
> > }
> >
> > static MemoryRegionSection *phys_page_find(PhysPageEntry lp, hwaddr index,
> > @@ -237,10 +230,10 @@ static MemoryRegionSection
> > *address_space_lookup_region(AddressSpaceDispatch *d,
> > subpage_t *subpage;
> >
> > section = phys_page_find(d->phys_map, addr >> TARGET_PAGE_BITS,
> > - d->nodes, d->sections);
> > + d->map.nodes, d->map.sections);
> > if (resolve_subpage && section->mr->subpage) {
> > subpage = container_of(section->mr, subpage_t, iomem);
> > - section = &d->sections[subpage->sub_section[SUBPAGE_IDX(addr)]];
> > + section =
> > &d->map.sections[subpage->sub_section[SUBPAGE_IDX(addr)]];
> > }
> > return section;
> > }
> > @@ -708,7 +701,7 @@ hwaddr memory_region_section_get_iotlb(CPUArchState
> > *env,
> > iotlb |= PHYS_SECTION_ROM;
> > }
> > } else {
> > - iotlb = section - address_space_memory.dispatch->sections;
> > + iotlb = section - address_space_memory.dispatch->map.sections;
> > iotlb += xlat;
> > }
> >
> > @@ -747,23 +740,23 @@ void phys_mem_set_alloc(void *(*alloc)(size_t))
> > phys_mem_alloc = alloc;
> > }
> >
> > -static uint16_t phys_section_add(MemoryRegionSection *section)
> > +static uint16_t phys_section_add(PhysPageMap *map,
> > + MemoryRegionSection *section)
> > {
> > /* The physical section number is ORed with a page-aligned
> > * pointer to produce the iotlb entries. Thus it should
> > * never overflow into the page-aligned value.
> > */
> > - assert(next_map.sections_nb < TARGET_PAGE_SIZE);
> > + assert(map->sections_nb < TARGET_PAGE_SIZE);
> >
> > - if (next_map.sections_nb == next_map.sections_nb_alloc) {
> > - next_map.sections_nb_alloc = MAX(next_map.sections_nb_alloc * 2,
> > - 16);
> > - next_map.sections = g_renew(MemoryRegionSection, next_map.sections,
> > - next_map.sections_nb_alloc);
> > + if (map->sections_nb == map->sections_nb_alloc) {
> > + map->sections_nb_alloc = MAX(map->sections_nb_alloc * 2, 16);
> > + map->sections = g_renew(MemoryRegionSection, map->sections,
> > + map->sections_nb_alloc);
> > }
> > - next_map.sections[next_map.sections_nb] = *section;
> > + map->sections[map->sections_nb] = *section;
> > memory_region_ref(section->mr);
> > - return next_map.sections_nb++;
> > + return map->sections_nb++;
> > }
> >
> > static void phys_section_destroy(MemoryRegion *mr)
> > @@ -785,7 +778,6 @@ static void phys_sections_free(PhysPageMap *map)
> > }
> > g_free(map->sections);
> > g_free(map->nodes);
> > - g_free(map);
> > }
> >
> > static void register_subpage(AddressSpaceDispatch *d, MemoryRegionSection
> > *section)
> > @@ -794,7 +786,7 @@ static void register_subpage(AddressSpaceDispatch *d,
> > MemoryRegionSection *secti
> > hwaddr base = section->offset_within_address_space
> > & TARGET_PAGE_MASK;
> > MemoryRegionSection *existing = phys_page_find(d->phys_map, base >>
> > TARGET_PAGE_BITS,
> > - next_map.nodes,
> > next_map.sections);
> > + d->map.nodes,
> > d->map.sections);
> > MemoryRegionSection subsection = {
> > .offset_within_address_space = base,
> > .size = int128_make64(TARGET_PAGE_SIZE),
> > @@ -807,13 +799,14 @@ static void register_subpage(AddressSpaceDispatch *d,
> > MemoryRegionSection *secti
> > subpage = subpage_init(d->as, base);
> > subsection.mr = &subpage->iomem;
> > phys_page_set(d, base >> TARGET_PAGE_BITS, 1,
> > - phys_section_add(&subsection));
> > + phys_section_add(&d->map, &subsection));
> > } else {
> > subpage = container_of(existing->mr, subpage_t, iomem);
> > }
> > start = section->offset_within_address_space & ~TARGET_PAGE_MASK;
> > end = start + int128_get64(section->size) - 1;
> > - subpage_register(subpage, start, end, phys_section_add(section));
> > + subpage_register(subpage, start, end,
> > + phys_section_add(&d->map, section));
> > }
> >
> >
> > @@ -821,7 +814,7 @@ static void register_multipage(AddressSpaceDispatch *d,
> > MemoryRegionSection *section)
> > {
> > hwaddr start_addr = section->offset_within_address_space;
> > - uint16_t section_index = phys_section_add(section);
> > + uint16_t section_index = phys_section_add(&d->map, section);
> > uint64_t num_pages = int128_get64(int128_rshift(section->size,
> > TARGET_PAGE_BITS));
> >
> > @@ -1605,7 +1598,7 @@ static subpage_t *subpage_init(AddressSpace *as,
> > hwaddr base)
> > return mmio;
> > }
> >
> > -static uint16_t dummy_section(MemoryRegion *mr)
> > +static uint16_t dummy_section(PhysPageMap *map, MemoryRegion *mr)
> > {
> > MemoryRegionSection section = {
> > .mr = mr,
> > @@ -1614,12 +1607,13 @@ static uint16_t dummy_section(MemoryRegion *mr)
> > .size = int128_2_64(),
> > };
> >
> > - return phys_section_add(§ion);
> > + return phys_section_add(map, §ion);
> > }
> >
> > MemoryRegion *iotlb_to_region(hwaddr index)
> > {
> > - return address_space_memory.dispatch->sections[index &
> > ~TARGET_PAGE_MASK].mr;
> > + return address_space_memory.dispatch->map.sections[
> > + index & ~TARGET_PAGE_MASK].mr;
> > }
> >
> > static void io_mem_init(void)
> > @@ -1636,7 +1630,17 @@ static void io_mem_init(void)
> > static void mem_begin(MemoryListener *listener)
> > {
> > AddressSpace *as = container_of(listener, AddressSpace,
> > dispatch_listener);
> > - AddressSpaceDispatch *d = g_new(AddressSpaceDispatch, 1);
> > + AddressSpaceDispatch *d = g_new0(AddressSpaceDispatch, 1);
> > + uint16_t n;
> > +
> > + n = dummy_section(&d->map, &io_mem_unassigned);
> > + assert(n == PHYS_SECTION_UNASSIGNED);
> > + n = dummy_section(&d->map, &io_mem_notdirty);
> > + assert(n == PHYS_SECTION_NOTDIRTY);
> > + n = dummy_section(&d->map, &io_mem_rom);
> > + assert(n == PHYS_SECTION_ROM);
> > + n = dummy_section(&d->map, &io_mem_watch);
> > + assert(n == PHYS_SECTION_WATCH);
> >
> > d->phys_map = (PhysPageEntry) { .ptr = PHYS_MAP_NODE_NIL, .is_leaf =
> > 0 };
> > d->as = as;
> > @@ -1649,37 +1653,12 @@ static void mem_commit(MemoryListener *listener)
> > AddressSpaceDispatch *cur = as->dispatch;
> > AddressSpaceDispatch *next = as->next_dispatch;
> >
> > - next->nodes = next_map.nodes;
> > - next->sections = next_map.sections;
> > -
> > as->dispatch = next;
> > - g_free(cur);
> > -}
> > -
> > -static void core_begin(MemoryListener *listener)
> > -{
> > - uint16_t n;
> >
> > - prev_map = g_new(PhysPageMap, 1);
> > - *prev_map = next_map;
> > -
> > - memset(&next_map, 0, sizeof(next_map));
> > - n = dummy_section(&io_mem_unassigned);
> > - assert(n == PHYS_SECTION_UNASSIGNED);
> > - n = dummy_section(&io_mem_notdirty);
> > - assert(n == PHYS_SECTION_NOTDIRTY);
> > - n = dummy_section(&io_mem_rom);
> > - assert(n == PHYS_SECTION_ROM);
> > - n = dummy_section(&io_mem_watch);
> > - assert(n == PHYS_SECTION_WATCH);
> > -}
> > -
> > -/* This listener's commit run after the other AddressSpaceDispatch
> > listeners'.
> > - * All AddressSpaceDispatch instances have switched to the next map.
> > - */
> > -static void core_commit(MemoryListener *listener)
> > -{
> > - phys_sections_free(prev_map);
> > + if (cur) {
> > + phys_sections_free(&cur->map);
> > + g_free(cur);
> > + }
> > }
> >
> > static void tcg_commit(MemoryListener *listener)
> > @@ -1707,8 +1686,6 @@ static void core_log_global_stop(MemoryListener
> > *listener)
> > }
> >
> > static MemoryListener core_memory_listener = {
> > - .begin = core_begin,
> > - .commit = core_commit,
> > .log_global_start = core_log_global_start,
> > .log_global_stop = core_log_global_stop,
> > .priority = 1,
> > --
> > 1.8.3.1
