[PATCH v1 8/8] accel/tcg: remove trace_vcpu_dstate TB checking

[Alex Bennée]

We removed the ability to do vcpu tcg tracing between:

  d9a6bad542 (docs: remove references to TCG tracing)
  and
  126d4123c5 (tracing: excise the tcg related from tracetool)

but missed a bunch of other code. Lets continue the clean-up by
removing the extra field from tb_hash saving us 4 bytes per-TB and the
additional cost of hashing/checking something that was always empty
anyway.

There remain some per-vcpu trace points which don't look as though
they are called anywhere and the command line/QMP machinery to
clean-up.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
---
 accel/tcg/tb-hash.h       |  6 +++---
 include/exec/exec-all.h   |  3 ---
 accel/tcg/cpu-exec.c      |  6 +-----
 accel/tcg/translate-all.c | 13 ++-----------
 4 files changed, 6 insertions(+), 22 deletions(-)

diff --git a/accel/tcg/tb-hash.h b/accel/tcg/tb-hash.h
index 0a273d9605..d58115ee70 100644
--- a/accel/tcg/tb-hash.h
+++ b/accel/tcg/tb-hash.h
@@ -60,10 +60,10 @@ static inline unsigned int 
tb_jmp_cache_hash_func(target_ulong pc)
 #endif /* CONFIG_SOFTMMU */
 
 static inline
-uint32_t tb_hash_func(tb_page_addr_t phys_pc, target_ulong pc, uint32_t flags,
-                      uint32_t cf_mask, uint32_t trace_vcpu_dstate)
+uint32_t tb_hash_func(tb_page_addr_t phys_pc, target_ulong pc,
+                      uint32_t flags, uint32_t cf_mask)
 {
-    return qemu_xxhash7(phys_pc, pc, flags, cf_mask, trace_vcpu_dstate);
+    return qemu_xxhash6(phys_pc, pc, flags, cf_mask);
 }
 
 #endif
diff --git a/include/exec/exec-all.h b/include/exec/exec-all.h
index 311e5fb422..21469da064 100644
--- a/include/exec/exec-all.h
+++ b/include/exec/exec-all.h
@@ -479,9 +479,6 @@ struct TranslationBlock {
 #define CF_CLUSTER_MASK  0xff000000 /* Top 8 bits are cluster ID */
 #define CF_CLUSTER_SHIFT 24
 
-    /* Per-vCPU dynamic tracing state used to generate this TB */
-    uint32_t trace_vcpu_dstate;
-
     /*
      * Above fields used for comparing
      */
diff --git a/accel/tcg/cpu-exec.c b/accel/tcg/cpu-exec.c
index a565a3f8ec..86f0276b1d 100644
--- a/accel/tcg/cpu-exec.c
+++ b/accel/tcg/cpu-exec.c
@@ -188,7 +188,6 @@ static inline TranslationBlock *tb_lookup(CPUState *cpu, 
target_ulong pc,
                tb->pc == pc &&
                tb->cs_base == cs_base &&
                tb->flags == flags &&
-               tb->trace_vcpu_dstate == *cpu->trace_dstate &&
                tb_cflags(tb) == cflags)) {
         return tb;
     }
@@ -494,7 +493,6 @@ struct tb_desc {
     tb_page_addr_t phys_page1;
     uint32_t flags;
     uint32_t cflags;
-    uint32_t trace_vcpu_dstate;
 };
 
 static bool tb_lookup_cmp(const void *p, const void *d)
@@ -506,7 +504,6 @@ static bool tb_lookup_cmp(const void *p, const void *d)
         tb->page_addr[0] == desc->phys_page1 &&
         tb->cs_base == desc->cs_base &&
         tb->flags == desc->flags &&
-        tb->trace_vcpu_dstate == desc->trace_vcpu_dstate &&
         tb_cflags(tb) == desc->cflags) {
         /* check next page if needed */
         if (tb->page_addr[1] == -1) {
@@ -537,14 +534,13 @@ TranslationBlock *tb_htable_lookup(CPUState *cpu, 
target_ulong pc,
     desc.cs_base = cs_base;
     desc.flags = flags;
     desc.cflags = cflags;
-    desc.trace_vcpu_dstate = *cpu->trace_dstate;
     desc.pc = pc;
     phys_pc = get_page_addr_code(desc.env, pc);
     if (phys_pc == -1) {
         return NULL;
     }
     desc.phys_page1 = phys_pc & TARGET_PAGE_MASK;
-    h = tb_hash_func(phys_pc, pc, flags, cflags, *cpu->trace_dstate);
+    h = tb_hash_func(phys_pc, pc, flags, cflags);
     return qht_lookup_custom(&tb_ctx.htable, &desc, h, tb_lookup_cmp);
 }
 
diff --git a/accel/tcg/translate-all.c b/accel/tcg/translate-all.c
index ef62a199c7..ce05cb4103 100644
--- a/accel/tcg/translate-all.c
+++ b/accel/tcg/translate-all.c
@@ -197,11 +197,6 @@ struct page_collection {
 #define V_L2_BITS 10
 #define V_L2_SIZE (1 << V_L2_BITS)
 
-/* Make sure all possible CPU event bits fit in tb->trace_vcpu_dstate */
-QEMU_BUILD_BUG_ON(CPU_TRACE_DSTATE_MAX_EVENTS >
-                  sizeof_field(TranslationBlock, trace_vcpu_dstate)
-                  * BITS_PER_BYTE);
-
 /*
  * L1 Mapping properties
  */
@@ -894,7 +889,6 @@ static bool tb_cmp(const void *ap, const void *bp)
         a->cs_base == b->cs_base &&
         a->flags == b->flags &&
         (tb_cflags(a) & ~CF_INVALID) == (tb_cflags(b) & ~CF_INVALID) &&
-        a->trace_vcpu_dstate == b->trace_vcpu_dstate &&
         a->page_addr[0] == b->page_addr[0] &&
         a->page_addr[1] == b->page_addr[1];
 }
@@ -1186,8 +1180,7 @@ static void do_tb_phys_invalidate(TranslationBlock *tb, 
bool rm_from_page_list)
 
     /* remove the TB from the hash list */
     phys_pc = tb->page_addr[0] + (tb->pc & ~TARGET_PAGE_MASK);
-    h = tb_hash_func(phys_pc, tb->pc, tb->flags, orig_cflags,
-                     tb->trace_vcpu_dstate);
+    h = tb_hash_func(phys_pc, tb->pc, tb->flags, orig_cflags);
     if (!qht_remove(&tb_ctx.htable, tb, h)) {
         return;
     }
@@ -1349,8 +1342,7 @@ tb_link_page(TranslationBlock *tb, tb_page_addr_t phys_pc,
     }
 
     /* add in the hash table */
-    h = tb_hash_func(phys_pc, tb->pc, tb->flags, tb->cflags,
-                     tb->trace_vcpu_dstate);
+    h = tb_hash_func(phys_pc, tb->pc, tb->flags, tb->cflags);
     qht_insert(&tb_ctx.htable, tb, h, &existing_tb);
 
     /* remove TB from the page(s) if we couldn't insert it */
@@ -1426,7 +1418,6 @@ TranslationBlock *tb_gen_code(CPUState *cpu,
     tb->cs_base = cs_base;
     tb->flags = flags;
     tb->cflags = cflags;
-    tb->trace_vcpu_dstate = *cpu->trace_dstate;
     tcg_ctx->tb_cflags = cflags;
  tb_overflow:
 
-- 
2.30.2