physmem: xen: Conditionalize use of the mapcache
Conditionalize use of the mapcache. This is in preparation to optionally disable the mapcache at runtime. Signed-off-by: Edgar E. Iglesias <edgar.iglesias@amd.com> Acked-by: Peter Xu <peterx@redhat.com> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Edgar E. Iglesias committed
Jul 23, 2025 at 11:56 UTC
c1d78ba63cf520841635594049ecf437b432b791
1 file changed
+8
-6
system/physmem.c
+8
-6
@@ -578,7 +578,9 @@ MemoryRegion *flatview_translate(FlatView *fv, hwaddr addr, hwaddr *xlat,
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is_write, true, &as, attrs);
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mr = section.mr;
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- if (xen_enabled() && memory_access_is_direct(mr, is_write, attrs)) {
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+ if (xen_map_cache_enabled() &&
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+ memory_access_is_direct(mr, is_write, attrs)) {
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+ /* mapcache: Next page may be unmapped or in a different bucket/VA. */
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hwaddr page = ((addr & TARGET_PAGE_MASK) + TARGET_PAGE_SIZE) - addr;
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*plen = MIN(page, *plen);
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}
@@ -2577,7 +2579,7 @@ static void reclaim_ramblock(RAMBlock *block)
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{
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if (block->flags & RAM_PREALLOC) {
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;
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- } else if (xen_enabled()) {
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+ } else if (xen_map_cache_enabled()) {
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xen_invalidate_map_cache_entry(block->host);
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#if !defined(_WIN32) && !defined(EMSCRIPTEN)
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} else if (block->fd >= 0) {
@@ -2736,7 +2738,7 @@ static void *qemu_ram_ptr_length(RAMBlock *block, ram_addr_t addr,
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len = *size;
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}
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- if (xen_enabled() && block->host == NULL) {
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+ if (xen_map_cache_enabled() && block->host == NULL) {
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/* We need to check if the requested address is in the RAM
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* because we don't want to map the entire memory in QEMU.
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* In that case just map the requested area.
@@ -2785,7 +2787,7 @@ RAMBlock *qemu_ram_block_from_host(void *ptr, bool round_offset,
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RAMBlock *block;
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uint8_t *host = ptr;
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- if (xen_enabled()) {
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+ if (xen_map_cache_enabled()) {
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ram_addr_t ram_addr;
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RCU_READ_LOCK_GUARD();
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ram_addr = xen_ram_addr_from_mapcache(ptr);
@@ -3787,7 +3789,7 @@ void address_space_unmap(AddressSpace *as, void *buffer, hwaddr len,
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if (is_write) {
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invalidate_and_set_dirty(mr, addr1, access_len);
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}
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- if (xen_enabled()) {
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+ if (xen_map_cache_enabled()) {
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xen_invalidate_map_cache_entry(buffer);
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}
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memory_region_unref(mr);
@@ -3898,7 +3900,7 @@ void address_space_cache_destroy(MemoryRegionCache *cache)
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return;
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}
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- if (xen_enabled()) {
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+ if (xen_map_cache_enabled()) {
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xen_invalidate_map_cache_entry(cache->ptr);
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}
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memory_region_unref(cache->mrs.mr);