From: KONRAD Frederic <fred.kon...@greensocs.com>
spinlock is only used in two cases:
* cpu-exec.c: to protect TranslationBlock
* mem_helper.c: for lock helper in target-i386 (which seems broken).
It's a pthread_mutex_t in user-mode so better using QemuMutex directly in this
case.
It allows as well to reuse tb_lock mutex of TBContext in case of multithread
TCG.
Signed-off-by: KONRAD Frederic <fred.kon...@greensocs.com>
---
cpu-exec.c | 15 +++++++++++----
include/exec/exec-all.h | 4 ++--
linux-user/main.c | 6 +++---
target-i386/mem_helper.c | 16 +++++++++++++---
tcg/i386/tcg-target.c | 8 ++++++++
5 files changed, 37 insertions(+), 12 deletions(-)
diff --git a/cpu-exec.c b/cpu-exec.c
index 97805cc..f3358a9 100644
--- a/cpu-exec.c
+++ b/cpu-exec.c
@@ -361,7 +361,9 @@ int cpu_exec(CPUState *cpu)
SyncClocks sc;
/* This must be volatile so it is not trashed by longjmp() */
+#if defined(CONFIG_USER_ONLY)
volatile bool have_tb_lock = false;
+#endif
if (async_safe_work_pending()) {
cpu->exit_request = 1;
@@ -488,8 +490,10 @@ int cpu_exec(CPUState *cpu)
cpu->exception_index = EXCP_INTERRUPT;
cpu_loop_exit(cpu);
}
- spin_lock(&tcg_ctx.tb_ctx.tb_lock);
+#if defined(CONFIG_USER_ONLY)
+ qemu_mutex_lock(&tcg_ctx.tb_ctx.tb_lock);
have_tb_lock = true;
+#endif
tb = tb_find_fast(cpu);
/* Note: we do it here to avoid a gcc bug on Mac OS X when
doing it in tb_find_slow */
@@ -511,9 +515,10 @@ int cpu_exec(CPUState *cpu)
tb_add_jump((TranslationBlock *)(next_tb & ~TB_EXIT_MASK),
next_tb & TB_EXIT_MASK, tb);
}
+#if defined(CONFIG_USER_ONLY)
have_tb_lock = false;
- spin_unlock(&tcg_ctx.tb_ctx.tb_lock);
-
+ qemu_mutex_unlock(&tcg_ctx.tb_ctx.tb_lock);
+#endif
/* cpu_interrupt might be called while translating the
TB, but before it is linked into a potentially
infinite loop and becomes env->current_tb. Avoid
@@ -580,10 +585,12 @@ int cpu_exec(CPUState *cpu)
x86_cpu = X86_CPU(cpu);
env = &x86_cpu->env;
#endif
+#if defined(CONFIG_USER_ONLY)
if (have_tb_lock) {
- spin_unlock(&tcg_ctx.tb_ctx.tb_lock);
+ qemu_mutex_unlock(&tcg_ctx.tb_ctx.tb_lock);
have_tb_lock = false;
}
+#endif
}
} /* for(;;) */
diff --git a/include/exec/exec-all.h b/include/exec/exec-all.h
index a6fce04..55a6ff2 100644
--- a/include/exec/exec-all.h
+++ b/include/exec/exec-all.h
@@ -176,7 +176,7 @@ struct TranslationBlock {
struct TranslationBlock *jmp_first;
};
-#include "exec/spinlock.h"
+#include "qemu/thread.h"
typedef struct TBContext TBContext;
@@ -186,7 +186,7 @@ struct TBContext {
TranslationBlock *tb_phys_hash[CODE_GEN_PHYS_HASH_SIZE];
int nb_tbs;
/* any access to the tbs or the page table must use this lock */
- spinlock_t tb_lock;
+ QemuMutex tb_lock;
/* statistics */
int tb_flush_count;
diff --git a/linux-user/main.c b/linux-user/main.c
index 05914b1..20e7199 100644
--- a/linux-user/main.c
+++ b/linux-user/main.c
@@ -107,7 +107,7 @@ static int pending_cpus;
/* Make sure everything is in a consistent state for calling fork(). */
void fork_start(void)
{
- pthread_mutex_lock(&tcg_ctx.tb_ctx.tb_lock);
+ qemu_mutex_lock(&tcg_ctx.tb_ctx.tb_lock);
pthread_mutex_lock(&exclusive_lock);
mmap_fork_start();
}
@@ -129,11 +129,11 @@ void fork_end(int child)
pthread_mutex_init(&cpu_list_mutex, NULL);
pthread_cond_init(&exclusive_cond, NULL);
pthread_cond_init(&exclusive_resume, NULL);
- pthread_mutex_init(&tcg_ctx.tb_ctx.tb_lock, NULL);
+ qemu_mutex_init(&tcg_ctx.tb_ctx.tb_lock);
gdbserver_fork(thread_cpu);
} else {
pthread_mutex_unlock(&exclusive_lock);
- pthread_mutex_unlock(&tcg_ctx.tb_ctx.tb_lock);
+ qemu_mutex_unlock(&tcg_ctx.tb_ctx.tb_lock);
}
}
diff --git a/target-i386/mem_helper.c b/target-i386/mem_helper.c
index 1aec8a5..7106cc3 100644
--- a/target-i386/mem_helper.c
+++ b/target-i386/mem_helper.c
@@ -23,17 +23,27 @@
/* broken thread support */
-static spinlock_t global_cpu_lock = SPIN_LOCK_UNLOCKED;
+#if defined(CONFIG_USER_ONLY)
+QemuMutex global_cpu_lock;
void helper_lock(void)
{
- spin_lock(&global_cpu_lock);
+ qemu_mutex_lock(&global_cpu_lock);
}
void helper_unlock(void)
{
- spin_unlock(&global_cpu_lock);
+ qemu_mutex_unlock(&global_cpu_lock);
}
+#else
+void helper_lock(void)
+{
+}
+
+void helper_unlock(void)
+{
+}
+#endif
void helper_cmpxchg8b(CPUX86State *env, target_ulong a0)
{
diff --git a/tcg/i386/tcg-target.c b/tcg/i386/tcg-target.c
index ff4d9cf..0d7c99c 100644
--- a/tcg/i386/tcg-target.c
+++ b/tcg/i386/tcg-target.c
@@ -24,6 +24,10 @@
#include "tcg-be-ldst.h"
+#if defined(CONFIG_USER_ONLY)
+extern QemuMutex global_cpu_lock;
+#endif
+
#ifndef NDEBUG
static const char * const tcg_target_reg_names[TCG_TARGET_NB_REGS] = {
#if TCG_TARGET_REG_BITS == 64
@@ -2342,6 +2346,10 @@ static void tcg_target_init(TCGContext *s)
tcg_regset_set_reg(s->reserved_regs, TCG_REG_CALL_STACK);
tcg_add_target_add_op_defs(x86_op_defs);
+
+#if defined(CONFIG_USER_ONLY)
+ qemu_mutex_init(global_cpu_lock);
+#endif
}
typedef struct {
--
1.9.0
