new file mode 100644
@@ -0,0 +1,37 @@
+/*
+ * Internal declarations for Tiny Code Generator for QEMU
+ *
+ * Copyright (c) 2008 Fabrice Bellard
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#ifndef TCG_INTERNAL_H
+#define TCG_INTERNAL_H 1
+
+#define TCG_HIGHWATER 1024
+
+extern TCGContext **tcg_ctxs;
+extern unsigned int n_tcg_ctxs;
+
+bool tcg_region_alloc(TCGContext *s);
+void tcg_region_initial_alloc(TCGContext *s);
+void tcg_region_prologue_set(TCGContext *s);
+
+#endif /* TCG_INTERNAL_H */
new file mode 100644
@@ -0,0 +1,572 @@
+/*
+ * Memory region management for Tiny Code Generator for QEMU
+ *
+ * Copyright (c) 2008 Fabrice Bellard
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "qemu/osdep.h"
+#include "exec/exec-all.h"
+#include "tcg/tcg.h"
+#if !defined(CONFIG_USER_ONLY)
+#include "hw/boards.h"
+#endif
+#include "tcg-internal.h"
+
+
+struct tcg_region_tree {
+ QemuMutex lock;
+ GTree *tree;
+ /* padding to avoid false sharing is computed at run-time */
+};
+
+/*
+ * We divide code_gen_buffer into equally-sized "regions" that TCG threads
+ * dynamically allocate from as demand dictates. Given appropriate region
+ * sizing, this minimizes flushes even when some TCG threads generate a lot
+ * more code than others.
+ */
+struct tcg_region_state {
+ QemuMutex lock;
+
+ /* fields set at init time */
+ void *start;
+ void *start_aligned;
+ void *end;
+ size_t n;
+ size_t size; /* size of one region */
+ size_t stride; /* .size + guard size */
+
+ /* fields protected by the lock */
+ size_t current; /* current region index */
+ size_t agg_size_full; /* aggregate size of full regions */
+};
+
+static struct tcg_region_state region;
+
+/*
+ * This is an array of struct tcg_region_tree's, with padding.
+ * We use void * to simplify the computation of region_trees[i]; each
+ * struct is found every tree_size bytes.
+ */
+static void *region_trees;
+static size_t tree_size;
+
+/* compare a pointer @ptr and a tb_tc @s */
+static int ptr_cmp_tb_tc(const void *ptr, const struct tb_tc *s)
+{
+ if (ptr >= s->ptr + s->size) {
+ return 1;
+ } else if (ptr < s->ptr) {
+ return -1;
+ }
+ return 0;
+}
+
+static gint tb_tc_cmp(gconstpointer ap, gconstpointer bp)
+{
+ const struct tb_tc *a = ap;
+ const struct tb_tc *b = bp;
+
+ /*
+ * When both sizes are set, we know this isn't a lookup.
+ * This is the most likely case: every TB must be inserted; lookups
+ * are a lot less frequent.
+ */
+ if (likely(a->size && b->size)) {
+ if (a->ptr > b->ptr) {
+ return 1;
+ } else if (a->ptr < b->ptr) {
+ return -1;
+ }
+ /* a->ptr == b->ptr should happen only on deletions */
+ g_assert(a->size == b->size);
+ return 0;
+ }
+ /*
+ * All lookups have either .size field set to 0.
+ * From the glib sources we see that @ap is always the lookup key. However
+ * the docs provide no guarantee, so we just mark this case as likely.
+ */
+ if (likely(a->size == 0)) {
+ return ptr_cmp_tb_tc(a->ptr, b);
+ }
+ return ptr_cmp_tb_tc(b->ptr, a);
+}
+
+static void tcg_region_trees_init(void)
+{
+ size_t i;
+
+ tree_size = ROUND_UP(sizeof(struct tcg_region_tree), qemu_dcache_linesize);
+ region_trees = qemu_memalign(qemu_dcache_linesize, region.n * tree_size);
+ for (i = 0; i < region.n; i++) {
+ struct tcg_region_tree *rt = region_trees + i * tree_size;
+
+ qemu_mutex_init(&rt->lock);
+ rt->tree = g_tree_new(tb_tc_cmp);
+ }
+}
+
+static struct tcg_region_tree *tc_ptr_to_region_tree(const void *p)
+{
+ size_t region_idx;
+
+ /*
+ * Like tcg_splitwx_to_rw, with no assert. The pc may come from
+ * a signal handler over which the caller has no control.
+ */
+ if (!in_code_gen_buffer(p)) {
+ p -= tcg_splitwx_diff;
+ if (!in_code_gen_buffer(p)) {
+ return NULL;
+ }
+ }
+
+ if (p < region.start_aligned) {
+ region_idx = 0;
+ } else {
+ ptrdiff_t offset = p - region.start_aligned;
+
+ if (offset > region.stride * (region.n - 1)) {
+ region_idx = region.n - 1;
+ } else {
+ region_idx = offset / region.stride;
+ }
+ }
+ return region_trees + region_idx * tree_size;
+}
+
+void tcg_tb_insert(TranslationBlock *tb)
+{
+ struct tcg_region_tree *rt = tc_ptr_to_region_tree(tb->tc.ptr);
+
+ g_assert(rt != NULL);
+ qemu_mutex_lock(&rt->lock);
+ g_tree_insert(rt->tree, &tb->tc, tb);
+ qemu_mutex_unlock(&rt->lock);
+}
+
+void tcg_tb_remove(TranslationBlock *tb)
+{
+ struct tcg_region_tree *rt = tc_ptr_to_region_tree(tb->tc.ptr);
+
+ g_assert(rt != NULL);
+ qemu_mutex_lock(&rt->lock);
+ g_tree_remove(rt->tree, &tb->tc);
+ qemu_mutex_unlock(&rt->lock);
+}
+
+/*
+ * Find the TB 'tb' such that
+ * tb->tc.ptr <= tc_ptr < tb->tc.ptr + tb->tc.size
+ * Return NULL if not found.
+ */
+TranslationBlock *tcg_tb_lookup(uintptr_t tc_ptr)
+{
+ struct tcg_region_tree *rt = tc_ptr_to_region_tree((void *)tc_ptr);
+ TranslationBlock *tb;
+ struct tb_tc s = { .ptr = (void *)tc_ptr };
+
+ if (rt == NULL) {
+ return NULL;
+ }
+
+ qemu_mutex_lock(&rt->lock);
+ tb = g_tree_lookup(rt->tree, &s);
+ qemu_mutex_unlock(&rt->lock);
+ return tb;
+}
+
+static void tcg_region_tree_lock_all(void)
+{
+ size_t i;
+
+ for (i = 0; i < region.n; i++) {
+ struct tcg_region_tree *rt = region_trees + i * tree_size;
+
+ qemu_mutex_lock(&rt->lock);
+ }
+}
+
+static void tcg_region_tree_unlock_all(void)
+{
+ size_t i;
+
+ for (i = 0; i < region.n; i++) {
+ struct tcg_region_tree *rt = region_trees + i * tree_size;
+
+ qemu_mutex_unlock(&rt->lock);
+ }
+}
+
+void tcg_tb_foreach(GTraverseFunc func, gpointer user_data)
+{
+ size_t i;
+
+ tcg_region_tree_lock_all();
+ for (i = 0; i < region.n; i++) {
+ struct tcg_region_tree *rt = region_trees + i * tree_size;
+
+ g_tree_foreach(rt->tree, func, user_data);
+ }
+ tcg_region_tree_unlock_all();
+}
+
+size_t tcg_nb_tbs(void)
+{
+ size_t nb_tbs = 0;
+ size_t i;
+
+ tcg_region_tree_lock_all();
+ for (i = 0; i < region.n; i++) {
+ struct tcg_region_tree *rt = region_trees + i * tree_size;
+
+ nb_tbs += g_tree_nnodes(rt->tree);
+ }
+ tcg_region_tree_unlock_all();
+ return nb_tbs;
+}
+
+static gboolean tcg_region_tree_traverse(gpointer k, gpointer v, gpointer data)
+{
+ TranslationBlock *tb = v;
+
+ tb_destroy(tb);
+ return FALSE;
+}
+
+static void tcg_region_tree_reset_all(void)
+{
+ size_t i;
+
+ tcg_region_tree_lock_all();
+ for (i = 0; i < region.n; i++) {
+ struct tcg_region_tree *rt = region_trees + i * tree_size;
+
+ g_tree_foreach(rt->tree, tcg_region_tree_traverse, NULL);
+ /* Increment the refcount first so that destroy acts as a reset */
+ g_tree_ref(rt->tree);
+ g_tree_destroy(rt->tree);
+ }
+ tcg_region_tree_unlock_all();
+}
+
+static void tcg_region_bounds(size_t curr_region, void **pstart, void **pend)
+{
+ void *start, *end;
+
+ start = region.start_aligned + curr_region * region.stride;
+ end = start + region.size;
+
+ if (curr_region == 0) {
+ start = region.start;
+ }
+ if (curr_region == region.n - 1) {
+ end = region.end;
+ }
+
+ *pstart = start;
+ *pend = end;
+}
+
+static void tcg_region_assign(TCGContext *s, size_t curr_region)
+{
+ void *start, *end;
+
+ tcg_region_bounds(curr_region, &start, &end);
+
+ s->code_gen_buffer = start;
+ s->code_gen_ptr = start;
+ s->code_gen_buffer_size = end - start;
+ s->code_gen_highwater = end - TCG_HIGHWATER;
+}
+
+static bool tcg_region_alloc__locked(TCGContext *s)
+{
+ if (region.current == region.n) {
+ return true;
+ }
+ tcg_region_assign(s, region.current);
+ region.current++;
+ return false;
+}
+
+/*
+ * Request a new region once the one in use has filled up.
+ * Returns true on error.
+ */
+bool tcg_region_alloc(TCGContext *s)
+{
+ bool err;
+ /* read the region size now; alloc__locked will overwrite it on success */
+ size_t size_full = s->code_gen_buffer_size;
+
+ qemu_mutex_lock(®ion.lock);
+ err = tcg_region_alloc__locked(s);
+ if (!err) {
+ region.agg_size_full += size_full - TCG_HIGHWATER;
+ }
+ qemu_mutex_unlock(®ion.lock);
+ return err;
+}
+
+/*
+ * Perform a context's first region allocation.
+ * This function does _not_ increment region.agg_size_full.
+ */
+static void tcg_region_initial_alloc__locked(TCGContext *s)
+{
+ bool err = tcg_region_alloc__locked(s);
+ g_assert(!err);
+}
+
+void tcg_region_initial_alloc(TCGContext *s)
+{
+ qemu_mutex_lock(®ion.lock);
+ tcg_region_initial_alloc__locked(s);
+ qemu_mutex_unlock(®ion.lock);
+}
+
+/* Call from a safe-work context */
+void tcg_region_reset_all(void)
+{
+ unsigned int n_ctxs = qatomic_read(&n_tcg_ctxs);
+ unsigned int i;
+
+ qemu_mutex_lock(®ion.lock);
+ region.current = 0;
+ region.agg_size_full = 0;
+
+ for (i = 0; i < n_ctxs; i++) {
+ TCGContext *s = qatomic_read(&tcg_ctxs[i]);
+ tcg_region_initial_alloc__locked(s);
+ }
+ qemu_mutex_unlock(®ion.lock);
+
+ tcg_region_tree_reset_all();
+}
+
+#ifdef CONFIG_USER_ONLY
+static size_t tcg_n_regions(void)
+{
+ return 1;
+}
+#else
+/*
+ * It is likely that some vCPUs will translate more code than others, so we
+ * first try to set more regions than max_cpus, with those regions being of
+ * reasonable size. If that's not possible we make do by evenly dividing
+ * the code_gen_buffer among the vCPUs.
+ */
+static size_t tcg_n_regions(void)
+{
+ size_t i;
+
+ /* Use a single region if all we have is one vCPU thread */
+#if !defined(CONFIG_USER_ONLY)
+ MachineState *ms = MACHINE(qdev_get_machine());
+ unsigned int max_cpus = ms->smp.max_cpus;
+#endif
+ if (max_cpus == 1 || !qemu_tcg_mttcg_enabled()) {
+ return 1;
+ }
+
+ /* Try to have more regions than max_cpus, with each region being >= 2 MB */
+ for (i = 8; i > 0; i--) {
+ size_t regions_per_thread = i;
+ size_t region_size;
+
+ region_size = tcg_init_ctx.code_gen_buffer_size;
+ region_size /= max_cpus * regions_per_thread;
+
+ if (region_size >= 2 * 1024u * 1024) {
+ return max_cpus * regions_per_thread;
+ }
+ }
+ /* If we can't, then just allocate one region per vCPU thread */
+ return max_cpus;
+}
+#endif
+
+/*
+ * Initializes region partitioning.
+ *
+ * Called at init time from the parent thread (i.e. the one calling
+ * tcg_context_init), after the target's TCG globals have been set.
+ *
+ * Region partitioning works by splitting code_gen_buffer into separate regions,
+ * and then assigning regions to TCG threads so that the threads can translate
+ * code in parallel without synchronization.
+ *
+ * In softmmu the number of TCG threads is bounded by max_cpus, so we use at
+ * least max_cpus regions in MTTCG. In !MTTCG we use a single region.
+ * Note that the TCG options from the command-line (i.e. -accel accel=tcg,[...])
+ * must have been parsed before calling this function, since it calls
+ * qemu_tcg_mttcg_enabled().
+ *
+ * In user-mode we use a single region. Having multiple regions in user-mode
+ * is not supported, because the number of vCPU threads (recall that each thread
+ * spawned by the guest corresponds to a vCPU thread) is only bounded by the
+ * OS, and usually this number is huge (tens of thousands is not uncommon).
+ * Thus, given this large bound on the number of vCPU threads and the fact
+ * that code_gen_buffer is allocated at compile-time, we cannot guarantee
+ * that the availability of at least one region per vCPU thread.
+ *
+ * However, this user-mode limitation is unlikely to be a significant problem
+ * in practice. Multi-threaded guests share most if not all of their translated
+ * code, which makes parallel code generation less appealing than in softmmu.
+ */
+void tcg_region_init(void)
+{
+ void *buf = tcg_init_ctx.code_gen_buffer;
+ void *aligned;
+ size_t size = tcg_init_ctx.code_gen_buffer_size;
+ size_t page_size = qemu_real_host_page_size;
+ size_t region_size;
+ size_t n_regions;
+ size_t i;
+
+ n_regions = tcg_n_regions();
+
+ /* The first region will be 'aligned - buf' bytes larger than the others */
+ aligned = QEMU_ALIGN_PTR_UP(buf, page_size);
+ g_assert(aligned < tcg_init_ctx.code_gen_buffer + size);
+ /*
+ * Make region_size a multiple of page_size, using aligned as the start.
+ * As a result of this we might end up with a few extra pages at the end of
+ * the buffer; we will assign those to the last region.
+ */
+ region_size = (size - (aligned - buf)) / n_regions;
+ region_size = QEMU_ALIGN_DOWN(region_size, page_size);
+
+ /* A region must have at least 2 pages; one code, one guard */
+ g_assert(region_size >= 2 * page_size);
+
+ /* init the region struct */
+ qemu_mutex_init(®ion.lock);
+ region.n = n_regions;
+ region.size = region_size - page_size;
+ region.stride = region_size;
+ region.start = buf;
+ region.start_aligned = aligned;
+ /* page-align the end, since its last page will be a guard page */
+ region.end = QEMU_ALIGN_PTR_DOWN(buf + size, page_size);
+ /* account for that last guard page */
+ region.end -= page_size;
+
+ /*
+ * Set guard pages in the rw buffer, as that's the one into which
+ * buffer overruns could occur. Do not set guard pages in the rx
+ * buffer -- let that one use hugepages throughout.
+ */
+ for (i = 0; i < region.n; i++) {
+ void *start, *end;
+
+ tcg_region_bounds(i, &start, &end);
+
+ /*
+ * macOS 11.2 has a bug (Apple Feedback FB8994773) in which mprotect
+ * rejects a permission change from RWX -> NONE. Guard pages are
+ * nice for bug detection but are not essential; ignore any failure.
+ */
+ (void)qemu_mprotect_none(end, page_size);
+ }
+
+ tcg_region_trees_init();
+
+ /*
+ * Leave the initial context initialized to the first region.
+ * This will be the context into which we generate the prologue.
+ * It is also the only context for CONFIG_USER_ONLY.
+ */
+ tcg_region_initial_alloc__locked(&tcg_init_ctx);
+}
+
+void tcg_region_prologue_set(TCGContext *s)
+{
+ /* Deduct the prologue from the first region. */
+ g_assert(region.start == s->code_gen_buffer);
+ region.start = s->code_ptr;
+
+ /* Recompute boundaries of the first region. */
+ tcg_region_assign(s, 0);
+
+ /* Register the balance of the buffer with gdb. */
+ tcg_register_jit(tcg_splitwx_to_rx(region.start),
+ region.end - region.start);
+}
+
+/*
+ * Returns the size (in bytes) of all translated code (i.e. from all regions)
+ * currently in the cache.
+ * See also: tcg_code_capacity()
+ * Do not confuse with tcg_current_code_size(); that one applies to a single
+ * TCG context.
+ */
+size_t tcg_code_size(void)
+{
+ unsigned int n_ctxs = qatomic_read(&n_tcg_ctxs);
+ unsigned int i;
+ size_t total;
+
+ qemu_mutex_lock(®ion.lock);
+ total = region.agg_size_full;
+ for (i = 0; i < n_ctxs; i++) {
+ const TCGContext *s = qatomic_read(&tcg_ctxs[i]);
+ size_t size;
+
+ size = qatomic_read(&s->code_gen_ptr) - s->code_gen_buffer;
+ g_assert(size <= s->code_gen_buffer_size);
+ total += size;
+ }
+ qemu_mutex_unlock(®ion.lock);
+ return total;
+}
+
+/*
+ * Returns the code capacity (in bytes) of the entire cache, i.e. including all
+ * regions.
+ * See also: tcg_code_size()
+ */
+size_t tcg_code_capacity(void)
+{
+ size_t guard_size, capacity;
+
+ /* no need for synchronization; these variables are set at init time */
+ guard_size = region.stride - region.size;
+ capacity = region.end + guard_size - region.start;
+ capacity -= region.n * (guard_size + TCG_HIGHWATER);
+ return capacity;
+}
+
+size_t tcg_tb_phys_invalidate_count(void)
+{
+ unsigned int n_ctxs = qatomic_read(&n_tcg_ctxs);
+ unsigned int i;
+ size_t total = 0;
+
+ for (i = 0; i < n_ctxs; i++) {
+ const TCGContext *s = qatomic_read(&tcg_ctxs[i]);
+
+ total += qatomic_read(&s->tb_phys_invalidate_count);
+ }
+ return total;
+}
@@ -63,6 +63,7 @@
#include "elf.h"
#include "exec/log.h"
+#include "tcg-internal.h"
/* Forward declarations for functions declared in tcg-target.c.inc and
used here. */
@@ -153,10 +154,8 @@ static bool tcg_target_const_match(int64_t val, TCGType type, int ct);
static int tcg_out_ldst_finalize(TCGContext *s);
#endif
-#define TCG_HIGHWATER 1024
-
-static TCGContext **tcg_ctxs;
-static unsigned int n_tcg_ctxs;
+TCGContext **tcg_ctxs;
+unsigned int n_tcg_ctxs;
TCGv_env cpu_env = 0;
const void *tcg_code_gen_epilogue;
uintptr_t tcg_splitwx_diff;
@@ -165,42 +164,6 @@ uintptr_t tcg_splitwx_diff;
tcg_prologue_fn *tcg_qemu_tb_exec;
#endif
-struct tcg_region_tree {
- QemuMutex lock;
- GTree *tree;
- /* padding to avoid false sharing is computed at run-time */
-};
-
-/*
- * We divide code_gen_buffer into equally-sized "regions" that TCG threads
- * dynamically allocate from as demand dictates. Given appropriate region
- * sizing, this minimizes flushes even when some TCG threads generate a lot
- * more code than others.
- */
-struct tcg_region_state {
- QemuMutex lock;
-
- /* fields set at init time */
- void *start;
- void *start_aligned;
- void *end;
- size_t n;
- size_t size; /* size of one region */
- size_t stride; /* .size + guard size */
-
- /* fields protected by the lock */
- size_t current; /* current region index */
- size_t agg_size_full; /* aggregate size of full regions */
-};
-
-static struct tcg_region_state region;
-/*
- * This is an array of struct tcg_region_tree's, with padding.
- * We use void * to simplify the computation of region_trees[i]; each
- * struct is found every tree_size bytes.
- */
-static void *region_trees;
-static size_t tree_size;
static TCGRegSet tcg_target_available_regs[TCG_TYPE_COUNT];
static TCGRegSet tcg_target_call_clobber_regs;
@@ -457,453 +420,6 @@ static const TCGTargetOpDef constraint_sets[] = {
#include "tcg-target.c.inc"
-/* compare a pointer @ptr and a tb_tc @s */
-static int ptr_cmp_tb_tc(const void *ptr, const struct tb_tc *s)
-{
- if (ptr >= s->ptr + s->size) {
- return 1;
- } else if (ptr < s->ptr) {
- return -1;
- }
- return 0;
-}
-
-static gint tb_tc_cmp(gconstpointer ap, gconstpointer bp)
-{
- const struct tb_tc *a = ap;
- const struct tb_tc *b = bp;
-
- /*
- * When both sizes are set, we know this isn't a lookup.
- * This is the most likely case: every TB must be inserted; lookups
- * are a lot less frequent.
- */
- if (likely(a->size && b->size)) {
- if (a->ptr > b->ptr) {
- return 1;
- } else if (a->ptr < b->ptr) {
- return -1;
- }
- /* a->ptr == b->ptr should happen only on deletions */
- g_assert(a->size == b->size);
- return 0;
- }
- /*
- * All lookups have either .size field set to 0.
- * From the glib sources we see that @ap is always the lookup key. However
- * the docs provide no guarantee, so we just mark this case as likely.
- */
- if (likely(a->size == 0)) {
- return ptr_cmp_tb_tc(a->ptr, b);
- }
- return ptr_cmp_tb_tc(b->ptr, a);
-}
-
-static void tcg_region_trees_init(void)
-{
- size_t i;
-
- tree_size = ROUND_UP(sizeof(struct tcg_region_tree), qemu_dcache_linesize);
- region_trees = qemu_memalign(qemu_dcache_linesize, region.n * tree_size);
- for (i = 0; i < region.n; i++) {
- struct tcg_region_tree *rt = region_trees + i * tree_size;
-
- qemu_mutex_init(&rt->lock);
- rt->tree = g_tree_new(tb_tc_cmp);
- }
-}
-
-static struct tcg_region_tree *tc_ptr_to_region_tree(const void *p)
-{
- size_t region_idx;
-
- /*
- * Like tcg_splitwx_to_rw, with no assert. The pc may come from
- * a signal handler over which the caller has no control.
- */
- if (!in_code_gen_buffer(p)) {
- p -= tcg_splitwx_diff;
- if (!in_code_gen_buffer(p)) {
- return NULL;
- }
- }
-
- if (p < region.start_aligned) {
- region_idx = 0;
- } else {
- ptrdiff_t offset = p - region.start_aligned;
-
- if (offset > region.stride * (region.n - 1)) {
- region_idx = region.n - 1;
- } else {
- region_idx = offset / region.stride;
- }
- }
- return region_trees + region_idx * tree_size;
-}
-
-void tcg_tb_insert(TranslationBlock *tb)
-{
- struct tcg_region_tree *rt = tc_ptr_to_region_tree(tb->tc.ptr);
-
- g_assert(rt != NULL);
- qemu_mutex_lock(&rt->lock);
- g_tree_insert(rt->tree, &tb->tc, tb);
- qemu_mutex_unlock(&rt->lock);
-}
-
-void tcg_tb_remove(TranslationBlock *tb)
-{
- struct tcg_region_tree *rt = tc_ptr_to_region_tree(tb->tc.ptr);
-
- g_assert(rt != NULL);
- qemu_mutex_lock(&rt->lock);
- g_tree_remove(rt->tree, &tb->tc);
- qemu_mutex_unlock(&rt->lock);
-}
-
-/*
- * Find the TB 'tb' such that
- * tb->tc.ptr <= tc_ptr < tb->tc.ptr + tb->tc.size
- * Return NULL if not found.
- */
-TranslationBlock *tcg_tb_lookup(uintptr_t tc_ptr)
-{
- struct tcg_region_tree *rt = tc_ptr_to_region_tree((void *)tc_ptr);
- TranslationBlock *tb;
- struct tb_tc s = { .ptr = (void *)tc_ptr };
-
- if (rt == NULL) {
- return NULL;
- }
-
- qemu_mutex_lock(&rt->lock);
- tb = g_tree_lookup(rt->tree, &s);
- qemu_mutex_unlock(&rt->lock);
- return tb;
-}
-
-static void tcg_region_tree_lock_all(void)
-{
- size_t i;
-
- for (i = 0; i < region.n; i++) {
- struct tcg_region_tree *rt = region_trees + i * tree_size;
-
- qemu_mutex_lock(&rt->lock);
- }
-}
-
-static void tcg_region_tree_unlock_all(void)
-{
- size_t i;
-
- for (i = 0; i < region.n; i++) {
- struct tcg_region_tree *rt = region_trees + i * tree_size;
-
- qemu_mutex_unlock(&rt->lock);
- }
-}
-
-void tcg_tb_foreach(GTraverseFunc func, gpointer user_data)
-{
- size_t i;
-
- tcg_region_tree_lock_all();
- for (i = 0; i < region.n; i++) {
- struct tcg_region_tree *rt = region_trees + i * tree_size;
-
- g_tree_foreach(rt->tree, func, user_data);
- }
- tcg_region_tree_unlock_all();
-}
-
-size_t tcg_nb_tbs(void)
-{
- size_t nb_tbs = 0;
- size_t i;
-
- tcg_region_tree_lock_all();
- for (i = 0; i < region.n; i++) {
- struct tcg_region_tree *rt = region_trees + i * tree_size;
-
- nb_tbs += g_tree_nnodes(rt->tree);
- }
- tcg_region_tree_unlock_all();
- return nb_tbs;
-}
-
-static gboolean tcg_region_tree_traverse(gpointer k, gpointer v, gpointer data)
-{
- TranslationBlock *tb = v;
-
- tb_destroy(tb);
- return FALSE;
-}
-
-static void tcg_region_tree_reset_all(void)
-{
- size_t i;
-
- tcg_region_tree_lock_all();
- for (i = 0; i < region.n; i++) {
- struct tcg_region_tree *rt = region_trees + i * tree_size;
-
- g_tree_foreach(rt->tree, tcg_region_tree_traverse, NULL);
- /* Increment the refcount first so that destroy acts as a reset */
- g_tree_ref(rt->tree);
- g_tree_destroy(rt->tree);
- }
- tcg_region_tree_unlock_all();
-}
-
-static void tcg_region_bounds(size_t curr_region, void **pstart, void **pend)
-{
- void *start, *end;
-
- start = region.start_aligned + curr_region * region.stride;
- end = start + region.size;
-
- if (curr_region == 0) {
- start = region.start;
- }
- if (curr_region == region.n - 1) {
- end = region.end;
- }
-
- *pstart = start;
- *pend = end;
-}
-
-static void tcg_region_assign(TCGContext *s, size_t curr_region)
-{
- void *start, *end;
-
- tcg_region_bounds(curr_region, &start, &end);
-
- s->code_gen_buffer = start;
- s->code_gen_ptr = start;
- s->code_gen_buffer_size = end - start;
- s->code_gen_highwater = end - TCG_HIGHWATER;
-}
-
-static bool tcg_region_alloc__locked(TCGContext *s)
-{
- if (region.current == region.n) {
- return true;
- }
- tcg_region_assign(s, region.current);
- region.current++;
- return false;
-}
-
-/*
- * Request a new region once the one in use has filled up.
- * Returns true on error.
- */
-static bool tcg_region_alloc(TCGContext *s)
-{
- bool err;
- /* read the region size now; alloc__locked will overwrite it on success */
- size_t size_full = s->code_gen_buffer_size;
-
- qemu_mutex_lock(®ion.lock);
- err = tcg_region_alloc__locked(s);
- if (!err) {
- region.agg_size_full += size_full - TCG_HIGHWATER;
- }
- qemu_mutex_unlock(®ion.lock);
- return err;
-}
-
-/*
- * Perform a context's first region allocation.
- * This function does _not_ increment region.agg_size_full.
- */
-static void tcg_region_initial_alloc__locked(TCGContext *s)
-{
- bool err = tcg_region_alloc__locked(s);
- g_assert(!err);
-}
-
-#ifndef CONFIG_USER_ONLY
-static void tcg_region_initial_alloc(TCGContext *s)
-{
- qemu_mutex_lock(®ion.lock);
- tcg_region_initial_alloc__locked(s);
- qemu_mutex_unlock(®ion.lock);
-}
-#endif
-
-/* Call from a safe-work context */
-void tcg_region_reset_all(void)
-{
- unsigned int n_ctxs = qatomic_read(&n_tcg_ctxs);
- unsigned int i;
-
- qemu_mutex_lock(®ion.lock);
- region.current = 0;
- region.agg_size_full = 0;
-
- for (i = 0; i < n_ctxs; i++) {
- TCGContext *s = qatomic_read(&tcg_ctxs[i]);
- tcg_region_initial_alloc__locked(s);
- }
- qemu_mutex_unlock(®ion.lock);
-
- tcg_region_tree_reset_all();
-}
-
-#ifdef CONFIG_USER_ONLY
-static size_t tcg_n_regions(void)
-{
- return 1;
-}
-#else
-/*
- * It is likely that some vCPUs will translate more code than others, so we
- * first try to set more regions than max_cpus, with those regions being of
- * reasonable size. If that's not possible we make do by evenly dividing
- * the code_gen_buffer among the vCPUs.
- */
-static size_t tcg_n_regions(void)
-{
- size_t i;
-
- /* Use a single region if all we have is one vCPU thread */
-#if !defined(CONFIG_USER_ONLY)
- MachineState *ms = MACHINE(qdev_get_machine());
- unsigned int max_cpus = ms->smp.max_cpus;
-#endif
- if (max_cpus == 1 || !qemu_tcg_mttcg_enabled()) {
- return 1;
- }
-
- /* Try to have more regions than max_cpus, with each region being >= 2 MB */
- for (i = 8; i > 0; i--) {
- size_t regions_per_thread = i;
- size_t region_size;
-
- region_size = tcg_init_ctx.code_gen_buffer_size;
- region_size /= max_cpus * regions_per_thread;
-
- if (region_size >= 2 * 1024u * 1024) {
- return max_cpus * regions_per_thread;
- }
- }
- /* If we can't, then just allocate one region per vCPU thread */
- return max_cpus;
-}
-#endif
-
-/*
- * Initializes region partitioning.
- *
- * Called at init time from the parent thread (i.e. the one calling
- * tcg_context_init), after the target's TCG globals have been set.
- *
- * Region partitioning works by splitting code_gen_buffer into separate regions,
- * and then assigning regions to TCG threads so that the threads can translate
- * code in parallel without synchronization.
- *
- * In softmmu the number of TCG threads is bounded by max_cpus, so we use at
- * least max_cpus regions in MTTCG. In !MTTCG we use a single region.
- * Note that the TCG options from the command-line (i.e. -accel accel=tcg,[...])
- * must have been parsed before calling this function, since it calls
- * qemu_tcg_mttcg_enabled().
- *
- * In user-mode we use a single region. Having multiple regions in user-mode
- * is not supported, because the number of vCPU threads (recall that each thread
- * spawned by the guest corresponds to a vCPU thread) is only bounded by the
- * OS, and usually this number is huge (tens of thousands is not uncommon).
- * Thus, given this large bound on the number of vCPU threads and the fact
- * that code_gen_buffer is allocated at compile-time, we cannot guarantee
- * that the availability of at least one region per vCPU thread.
- *
- * However, this user-mode limitation is unlikely to be a significant problem
- * in practice. Multi-threaded guests share most if not all of their translated
- * code, which makes parallel code generation less appealing than in softmmu.
- */
-void tcg_region_init(void)
-{
- void *buf = tcg_init_ctx.code_gen_buffer;
- void *aligned;
- size_t size = tcg_init_ctx.code_gen_buffer_size;
- size_t page_size = qemu_real_host_page_size;
- size_t region_size;
- size_t n_regions;
- size_t i;
-
- n_regions = tcg_n_regions();
-
- /* The first region will be 'aligned - buf' bytes larger than the others */
- aligned = QEMU_ALIGN_PTR_UP(buf, page_size);
- g_assert(aligned < tcg_init_ctx.code_gen_buffer + size);
- /*
- * Make region_size a multiple of page_size, using aligned as the start.
- * As a result of this we might end up with a few extra pages at the end of
- * the buffer; we will assign those to the last region.
- */
- region_size = (size - (aligned - buf)) / n_regions;
- region_size = QEMU_ALIGN_DOWN(region_size, page_size);
-
- /* A region must have at least 2 pages; one code, one guard */
- g_assert(region_size >= 2 * page_size);
-
- /* init the region struct */
- qemu_mutex_init(®ion.lock);
- region.n = n_regions;
- region.size = region_size - page_size;
- region.stride = region_size;
- region.start = buf;
- region.start_aligned = aligned;
- /* page-align the end, since its last page will be a guard page */
- region.end = QEMU_ALIGN_PTR_DOWN(buf + size, page_size);
- /* account for that last guard page */
- region.end -= page_size;
-
- /*
- * Set guard pages in the rw buffer, as that's the one into which
- * buffer overruns could occur. Do not set guard pages in the rx
- * buffer -- let that one use hugepages throughout.
- */
- for (i = 0; i < region.n; i++) {
- void *start, *end;
-
- tcg_region_bounds(i, &start, &end);
-
- /*
- * macOS 11.2 has a bug (Apple Feedback FB8994773) in which mprotect
- * rejects a permission change from RWX -> NONE. Guard pages are
- * nice for bug detection but are not essential; ignore any failure.
- */
- (void)qemu_mprotect_none(end, page_size);
- }
-
- tcg_region_trees_init();
-
- /*
- * Leave the initial context initialized to the first region.
- * This will be the context into which we generate the prologue.
- * It is also the only context for CONFIG_USER_ONLY.
- */
- tcg_region_initial_alloc__locked(&tcg_init_ctx);
-}
-
-static void tcg_region_prologue_set(TCGContext *s)
-{
- /* Deduct the prologue from the first region. */
- g_assert(region.start == s->code_gen_buffer);
- region.start = s->code_ptr;
-
- /* Recompute boundaries of the first region. */
- tcg_region_assign(s, 0);
-
- /* Register the balance of the buffer with gdb. */
- tcg_register_jit(tcg_splitwx_to_rx(region.start),
- region.end - region.start);
-}
-
#ifdef CONFIG_DEBUG_TCG
const void *tcg_splitwx_to_rx(void *rw)
{
@@ -988,63 +504,6 @@ void tcg_register_thread(void)
}
#endif /* !CONFIG_USER_ONLY */
-/*
- * Returns the size (in bytes) of all translated code (i.e. from all regions)
- * currently in the cache.
- * See also: tcg_code_capacity()
- * Do not confuse with tcg_current_code_size(); that one applies to a single
- * TCG context.
- */
-size_t tcg_code_size(void)
-{
- unsigned int n_ctxs = qatomic_read(&n_tcg_ctxs);
- unsigned int i;
- size_t total;
-
- qemu_mutex_lock(®ion.lock);
- total = region.agg_size_full;
- for (i = 0; i < n_ctxs; i++) {
- const TCGContext *s = qatomic_read(&tcg_ctxs[i]);
- size_t size;
-
- size = qatomic_read(&s->code_gen_ptr) - s->code_gen_buffer;
- g_assert(size <= s->code_gen_buffer_size);
- total += size;
- }
- qemu_mutex_unlock(®ion.lock);
- return total;
-}
-
-/*
- * Returns the code capacity (in bytes) of the entire cache, i.e. including all
- * regions.
- * See also: tcg_code_size()
- */
-size_t tcg_code_capacity(void)
-{
- size_t guard_size, capacity;
-
- /* no need for synchronization; these variables are set at init time */
- guard_size = region.stride - region.size;
- capacity = region.end + guard_size - region.start;
- capacity -= region.n * (guard_size + TCG_HIGHWATER);
- return capacity;
-}
-
-size_t tcg_tb_phys_invalidate_count(void)
-{
- unsigned int n_ctxs = qatomic_read(&n_tcg_ctxs);
- unsigned int i;
- size_t total = 0;
-
- for (i = 0; i < n_ctxs; i++) {
- const TCGContext *s = qatomic_read(&tcg_ctxs[i]);
-
- total += qatomic_read(&s->tb_phys_invalidate_count);
- }
- return total;
-}
-
/* pool based memory allocation */
void *tcg_malloc_internal(TCGContext *s, int size)
{
@@ -2,6 +2,7 @@ tcg_ss = ss.source_set()
tcg_ss.add(files(
'optimize.c',
+ 'region.c',
'tcg.c',
'tcg-common.c',
'tcg-op.c',