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From: "Alex Bennée" <alex.bennee@linaro.org>
To: richard.henderson@linaro.org
Cc: "Paolo Bonzini" <pbonzini@redhat.com>,
	cota@braap.org, "Alex Bennée" <alex.bennee@linaro.org>,
	qemu-devel@nongnu.org
Subject: [RFC PATCH 3/5] accel/tcg: drop the use of CF_HASH_MASK and rename params
Date: Wed, 24 Feb 2021 16:58:09 +0000	[thread overview]
Message-ID: <20210224165811.11567-4-alex.bennee@linaro.org> (raw)
In-Reply-To: <20210224165811.11567-1-alex.bennee@linaro.org>

We don't really deal in cf_mask most of the time. The one time it's
relevant is when we want to remove an invalidated TB from the QHT
lookup. Everywhere else we should be looking up things without
CF_INVALID set.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
---
 include/exec/exec-all.h   |  4 +---
 include/exec/tb-lookup.h  |  9 ++++++---
 accel/tcg/cpu-exec.c      | 16 ++++++++--------
 accel/tcg/tcg-runtime.c   |  2 +-
 accel/tcg/translate-all.c |  8 +++++---
 5 files changed, 21 insertions(+), 18 deletions(-)

diff --git a/include/exec/exec-all.h b/include/exec/exec-all.h
index 1a69c07add..acf66ab692 100644
--- a/include/exec/exec-all.h
+++ b/include/exec/exec-all.h
@@ -460,8 +460,6 @@ struct TranslationBlock {
 #define CF_PARALLEL    0x00080000 /* Generate code for a parallel context */
 #define CF_CLUSTER_MASK 0xff000000 /* Top 8 bits are cluster ID */
 #define CF_CLUSTER_SHIFT 24
-/* cflags' mask for hashing/comparison, basically ignore CF_INVALID */
-#define CF_HASH_MASK   (~CF_INVALID)
 
     /* Per-vCPU dynamic tracing state used to generate this TB */
     uint32_t trace_vcpu_dstate;
@@ -538,7 +536,7 @@ void tb_flush(CPUState *cpu);
 void tb_phys_invalidate(TranslationBlock *tb, tb_page_addr_t page_addr);
 TranslationBlock *tb_htable_lookup(CPUState *cpu, target_ulong pc,
                                    target_ulong cs_base, uint32_t flags,
-                                   uint32_t cf_mask);
+                                   uint32_t cflags);
 void tb_set_jmp_target(TranslationBlock *tb, int n, uintptr_t addr);
 
 /* GETPC is the true target of the return instruction that we'll execute.  */
diff --git a/include/exec/tb-lookup.h b/include/exec/tb-lookup.h
index b2247d458b..7b70412fae 100644
--- a/include/exec/tb-lookup.h
+++ b/include/exec/tb-lookup.h
@@ -19,11 +19,14 @@
 /* Might cause an exception, so have a longjmp destination ready */
 static inline TranslationBlock * tb_lookup(CPUState *cpu,
                                            target_ulong pc, target_ulong cs_base,
-                                           uint32_t flags, uint32_t cf_mask)
+                                           uint32_t flags, uint32_t cflags)
 {
     TranslationBlock *tb;
     uint32_t hash;
 
+    /* we should never be trying to look up an INVALID tb */
+    tcg_debug_assert(!(cflags & CF_INVALID));
+
     hash = tb_jmp_cache_hash_func(pc);
     tb = qatomic_rcu_read(&cpu->tb_jmp_cache[hash]);
 
@@ -32,10 +35,10 @@ static inline TranslationBlock * tb_lookup(CPUState *cpu,
                tb->cs_base == cs_base &&
                tb->flags == flags &&
                tb->trace_vcpu_dstate == *cpu->trace_dstate &&
-               (tb_cflags(tb) & (CF_HASH_MASK | CF_INVALID)) == cf_mask)) {
+               tb_cflags(tb) == cflags)) {
         return tb;
     }
-    tb = tb_htable_lookup(cpu, pc, cs_base, flags, cf_mask);
+    tb = tb_htable_lookup(cpu, pc, cs_base, flags, cflags);
     if (tb == NULL) {
         return NULL;
     }
diff --git a/accel/tcg/cpu-exec.c b/accel/tcg/cpu-exec.c
index 45286dc4b3..931da96c2b 100644
--- a/accel/tcg/cpu-exec.c
+++ b/accel/tcg/cpu-exec.c
@@ -307,7 +307,7 @@ struct tb_desc {
     CPUArchState *env;
     tb_page_addr_t phys_page1;
     uint32_t flags;
-    uint32_t cf_mask;
+    uint32_t cflags;
     uint32_t trace_vcpu_dstate;
 };
 
@@ -321,7 +321,7 @@ static bool tb_lookup_cmp(const void *p, const void *d)
         tb->cs_base == desc->cs_base &&
         tb->flags == desc->flags &&
         tb->trace_vcpu_dstate == desc->trace_vcpu_dstate &&
-        (tb_cflags(tb) & (CF_HASH_MASK | CF_INVALID)) == desc->cf_mask) {
+        tb_cflags(tb) == desc->cflags) {
         /* check next page if needed */
         if (tb->page_addr[1] == -1) {
             return true;
@@ -341,7 +341,7 @@ static bool tb_lookup_cmp(const void *p, const void *d)
 
 TranslationBlock *tb_htable_lookup(CPUState *cpu, target_ulong pc,
                                    target_ulong cs_base, uint32_t flags,
-                                   uint32_t cf_mask)
+                                   uint32_t cflags)
 {
     tb_page_addr_t phys_pc;
     struct tb_desc desc;
@@ -350,7 +350,7 @@ TranslationBlock *tb_htable_lookup(CPUState *cpu, target_ulong pc,
     desc.env = (CPUArchState *)cpu->env_ptr;
     desc.cs_base = cs_base;
     desc.flags = flags;
-    desc.cf_mask = cf_mask;
+    desc.cflags = cflags;
     desc.trace_vcpu_dstate = *cpu->trace_dstate;
     desc.pc = pc;
     phys_pc = get_page_addr_code(desc.env, pc);
@@ -358,7 +358,7 @@ TranslationBlock *tb_htable_lookup(CPUState *cpu, target_ulong pc,
         return NULL;
     }
     desc.phys_page1 = phys_pc & TARGET_PAGE_MASK;
-    h = tb_hash_func(phys_pc, pc, flags, cf_mask, *cpu->trace_dstate);
+    h = tb_hash_func(phys_pc, pc, flags, cflags, *cpu->trace_dstate);
     return qht_lookup_custom(&tb_ctx.htable, &desc, h, tb_lookup_cmp);
 }
 
@@ -418,7 +418,7 @@ static inline void tb_add_jump(TranslationBlock *tb, int n,
 
 static inline TranslationBlock *tb_find(CPUState *cpu,
                                         TranslationBlock *last_tb,
-                                        int tb_exit, uint32_t cf_mask)
+                                        int tb_exit, uint32_t cflags)
 {
     CPUArchState *env = (CPUArchState *)cpu->env_ptr;
     TranslationBlock *tb;
@@ -427,10 +427,10 @@ static inline TranslationBlock *tb_find(CPUState *cpu,
 
     cpu_get_tb_cpu_state(env, &pc, &cs_base, &flags);
 
-    tb = tb_lookup(cpu, pc, cs_base, flags, cf_mask);
+    tb = tb_lookup(cpu, pc, cs_base, flags, cflags);
     if (tb == NULL) {
         mmap_lock();
-        tb = tb_gen_code(cpu, pc, cs_base, flags, cf_mask);
+        tb = tb_gen_code(cpu, pc, cs_base, flags, cflags);
         mmap_unlock();
         /* We add the TB in the virtual pc hash table for the fast lookup */
         qatomic_set(&cpu->tb_jmp_cache[tb_jmp_cache_hash_func(pc)], tb);
diff --git a/accel/tcg/tcg-runtime.c b/accel/tcg/tcg-runtime.c
index 99403e3eb3..49f5de37e8 100644
--- a/accel/tcg/tcg-runtime.c
+++ b/accel/tcg/tcg-runtime.c
@@ -27,10 +27,10 @@
 #include "exec/helper-proto.h"
 #include "exec/cpu_ldst.h"
 #include "exec/exec-all.h"
-#include "exec/tb-lookup.h"
 #include "disas/disas.h"
 #include "exec/log.h"
 #include "tcg/tcg.h"
+#include "exec/tb-lookup.h"
 
 /* 32-bit helpers */
 
diff --git a/accel/tcg/translate-all.c b/accel/tcg/translate-all.c
index f29b47f090..0b0bfd35ab 100644
--- a/accel/tcg/translate-all.c
+++ b/accel/tcg/translate-all.c
@@ -1311,7 +1311,7 @@ static bool tb_cmp(const void *ap, const void *bp)
     return a->pc == b->pc &&
         a->cs_base == b->cs_base &&
         a->flags == b->flags &&
-        (tb_cflags(a) & CF_HASH_MASK) == (tb_cflags(b) & CF_HASH_MASK) &&
+        (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];
@@ -1616,6 +1616,7 @@ static void do_tb_phys_invalidate(TranslationBlock *tb, bool rm_from_page_list)
     PageDesc *p;
     uint32_t h;
     tb_page_addr_t phys_pc;
+    uint32_t orig_cflags = tb_cflags(tb);
 
     assert_memory_lock();
 
@@ -1626,7 +1627,7 @@ 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, tb_cflags(tb) & CF_HASH_MASK,
+    h = tb_hash_func(phys_pc, tb->pc, tb->flags, orig_cflags,
                      tb->trace_vcpu_dstate);
     if (!qht_remove(&tb_ctx.htable, tb, h)) {
         return;
@@ -1793,6 +1794,7 @@ tb_link_page(TranslationBlock *tb, tb_page_addr_t phys_pc,
     uint32_t h;
 
     assert_memory_lock();
+    tcg_debug_assert(!(tb->cflags & CF_INVALID));
 
     /*
      * Add the TB to the page list, acquiring first the pages's locks.
@@ -1811,7 +1813,7 @@ 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 & CF_HASH_MASK,
+    h = tb_hash_func(phys_pc, tb->pc, tb->flags, tb->cflags,
                      tb->trace_vcpu_dstate);
     qht_insert(&tb_ctx.htable, tb, h, &existing_tb);
 
-- 
2.20.1



  parent reply	other threads:[~2021-02-24 17:08 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-02-24 16:58 [RFC PATCH 0/5] Experimenting with tb-lookup tweaks Alex Bennée
2021-02-24 16:58 ` [RFC PATCH 1/5] accel/tcg: rename tb_lookup__cpu_state and hoist state extraction Alex Bennée
2021-02-24 16:58 ` [RFC PATCH 2/5] accel/tcg: move CF_CLUSTER calculation to curr_cflags Alex Bennée
2021-02-24 16:58 ` Alex Bennée [this message]
2021-02-24 16:58 ` [RFC PATCH 4/5] include/exec: lightly re-arrange TranslationBlock Alex Bennée
2021-02-24 16:58 ` [RFC PATCH 5/5] include/exec/tb-lookup: try and reduce branch prediction issues Alex Bennée
2021-02-25  0:28 ` [RFC PATCH 0/5] Experimenting with tb-lookup tweaks Richard Henderson
2021-02-25 10:15   ` Alex Bennée
2021-02-25 15:45 ` no-reply

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