[Qemu-devel] [PATCH 0/13] New shot at QEMUAccel

[Qemu-devel] [PATCH 0/13] New shot at QEMUAccel

[Glauber Costa]

Hi guys,

This is a new version of the QEMUAccel work. To start with, I decided
to keep the name for now. We don't have that many functions that are not
cpu-related to justify splitting the structure into many. Plus, this is one
of the less confusing names we came up with.

The code I'm posting is tested with kqemu for both i386 and x86_64, and it works.
So, if you guys feel like it, I can say it's ready  for inclusion (which obviously
does not mean bug-free). It is not complete, however.

There are still some pieces of kqemu code that does not work. Specially the interrupt
code in cpu-exec.c , which relies on the tricky longjmp.

Comments are very welcome.

[Qemu-devel] [PATCH 01/13] [PATCH] make cpu_exec_init symmetric

[Glauber Costa]

we put all the code that needs to be executed only at cpu0
out of cpu_exec_init(), in exec_init(). It is executed
before machine_init(), and only once. With this change,
code cpu_exec_init() is completely symmetric.
---
 exec-all.h |    1 +
 exec.c     |   15 +++++++++------
 vl.c       |    1 +
 3 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/exec-all.h b/exec-all.h
index d8c6c33..8c32858 100644
--- a/exec-all.h
+++ b/exec-all.h
@@ -82,6 +82,7 @@ int cpu_restore_state_copy(struct TranslationBlock *tb,
                            void *puc);
 void cpu_resume_from_signal(CPUState *env1, void *puc);
 void cpu_exec_init(CPUState *env);
+void exec_init(void);
 int page_unprotect(target_ulong address, unsigned long pc, void *puc);
 void tb_invalidate_phys_page_range(target_phys_addr_t start, target_phys_addr_t end,
                                    int is_cpu_write_access);
diff --git a/exec.c b/exec.c
index 2fd0078..5384460 100644
--- a/exec.c
+++ b/exec.c
@@ -327,17 +327,20 @@ static void tlb_unprotect_code_phys(CPUState *env, ram_addr_t ram_addr,
                                     target_ulong vaddr);
 #endif
 
+/* Must be called once before any of attempts to call cpu_init */
+void exec_init(void)
+{
+    cpu_gen_init();
+    code_gen_ptr = code_gen_buffer;
+    page_init();
+    io_mem_init();
+}
+
 void cpu_exec_init(CPUState *env)
 {
     CPUState **penv;
     int cpu_index;
 
-    if (!code_gen_ptr) {
-        cpu_gen_init();
-        code_gen_ptr = code_gen_buffer;
-        page_init();
-        io_mem_init();
-    }
     env->next_cpu = NULL;
     penv = &first_cpu;
     cpu_index = 0;
diff --git a/vl.c b/vl.c
index 67712f0..5999b37 100644
--- a/vl.c
+++ b/vl.c
@@ -8576,6 +8576,7 @@ int main(int argc, char **argv)
         }
     }
 
+    exec_init();
     machine->init(ram_size, vga_ram_size, boot_devices, ds,
                   kernel_filename, kernel_cmdline, initrd_filename, cpu_model);
 
-- 
1.5.5

[Qemu-devel] [PATCH 02/13] [PATCH] split kqemu_init into two

[Glauber Costa]

we separate kqemu_init() into a part that depends on env,
and other that does not. The later can be initialized earlier
---
 exec.c                |    3 +++
 kqemu.c               |   10 +++++++---
 target-i386/helper2.c |    2 +-
 3 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/exec.c b/exec.c
index 5384460..dfedfc3 100644
--- a/exec.c
+++ b/exec.c
@@ -334,6 +334,9 @@ void exec_init(void)
     code_gen_ptr = code_gen_buffer;
     page_init();
     io_mem_init();
+#ifdef USE_KQEMU
+    kqemu_start();
+#endif
 }
 
 void cpu_exec_init(CPUState *env)
diff --git a/kqemu.c b/kqemu.c
index 88592ee..0e38d52 100644
--- a/kqemu.c
+++ b/kqemu.c
@@ -159,7 +159,7 @@ static void kqemu_update_cpuid(CPUState *env)
        accelerated code */
 }
 
-int kqemu_init(CPUState *env)
+int kqemu_start(void)
 {
     struct kqemu_init init;
     int ret, version;
@@ -238,13 +238,17 @@ int kqemu_init(CPUState *env)
         kqemu_fd = KQEMU_INVALID_FD;
         return -1;
     }
-    kqemu_update_cpuid(env);
-    env->kqemu_enabled = kqemu_allowed;
     nb_pages_to_flush = 0;
     nb_ram_pages_to_update = 0;
     return 0;
 }
 
+void kqemu_init_env(CPUState *env)
+{
+    kqemu_update_cpuid(env);
+    env->kqemu_enabled = kqemu_allowed;
+}
+
 void kqemu_flush_page(CPUState *env, target_ulong addr)
 {
 #if defined(DEBUG)
diff --git a/target-i386/helper2.c b/target-i386/helper2.c
index 6cf218f..1c0fcdb 100644
--- a/target-i386/helper2.c
+++ b/target-i386/helper2.c
@@ -113,7 +113,7 @@ CPUX86State *cpu_x86_init(const char *cpu_model)
     }
     cpu_reset(env);
 #ifdef USE_KQEMU
-    kqemu_init(env);
+    kqemu_init_env(env);
 #endif
     return env;
 }
-- 
1.5.5

[Qemu-devel] [PATCH 03/13] [PATCH] introduce QEMUAccel and fill it with interrupt specific driver

[Glauber Costa]

This patch introduces QEMUAccel, a placeholder for function pointers
that aims at helping qemu to abstract accelerators such as kqemu and
kvm (actually, the 'accelerator' name was proposed by avi kivity, since
he loves referring to kvm that way).

To begin with, the accelerator is given the opportunity to register a
cpu_interrupt function, to be called after the raw cpu_interrupt.
This has the side effect of, for the kqemu accelerator, calling kqemu_cpu_interrupt
everytime, which didn't use to happen. But looking at the code, this seems safe to me.

This patch applies on raw qemu.
---
 block-raw-posix.c |    5 -----
 exec-all.h        |   18 +++++++++++++++++-
 exec.c            |    2 ++
 kqemu.c           |   27 +++++++++++++++++----------
 vl.c              |    6 +-----
 5 files changed, 37 insertions(+), 21 deletions(-)

diff --git a/block-raw-posix.c b/block-raw-posix.c
index 6b0009e..61c23ba 100644
--- a/block-raw-posix.c
+++ b/block-raw-posix.c
@@ -250,11 +250,6 @@ static void aio_signal_handler(int signum)
     if (env) {
         /* stop the currently executing cpu because a timer occured */
         cpu_interrupt(env, CPU_INTERRUPT_EXIT);
-#ifdef USE_KQEMU
-        if (env->kqemu_enabled) {
-            kqemu_cpu_interrupt(env);
-        }
-#endif
     }
 #endif
 }
diff --git a/exec-all.h b/exec-all.h
index 8c32858..7b2d97d 100644
--- a/exec-all.h
+++ b/exec-all.h
@@ -578,6 +578,23 @@ static inline target_ulong get_phys_addr_code(CPUState *env1, target_ulong addr)
 }
 #endif
 
+typedef struct QEMUAccel {
+    void (*cpu_interrupt)(CPUState *env);
+} QEMUAccel;
+
+extern QEMUAccel *current_accel;
+
+static inline void register_qemu_accel(QEMUAccel *accel)
+{
+    current_accel = accel;
+}
+
+static inline void accel_cpu_interrupt(CPUState *env)
+{
+    if (current_accel && current_accel->cpu_interrupt)
+        current_accel->cpu_interrupt(env);
+}
+
 #ifdef USE_KQEMU
 #define KQEMU_MODIFY_PAGE_MASK (0xff & ~(VGA_DIRTY_FLAG | CODE_DIRTY_FLAG))
 
@@ -587,7 +604,6 @@ void kqemu_flush_page(CPUState *env, target_ulong addr);
 void kqemu_flush(CPUState *env, int global);
 void kqemu_set_notdirty(CPUState *env, ram_addr_t ram_addr);
 void kqemu_modify_page(CPUState *env, ram_addr_t ram_addr);
-void kqemu_cpu_interrupt(CPUState *env);
 void kqemu_record_dump(void);
 
 static inline int kqemu_is_ok(CPUState *env)
diff --git a/exec.c b/exec.c
index dfedfc3..73360d3 100644
--- a/exec.c
+++ b/exec.c
@@ -1256,6 +1256,8 @@ void cpu_interrupt(CPUState *env, int mask)
         tb_reset_jump_recursive(tb);
         resetlock(&interrupt_lock);
     }
+
+    accel_cpu_interrupt(env);
 }
 
 void cpu_reset_interrupt(CPUState *env, int mask)
diff --git a/kqemu.c b/kqemu.c
index 0e38d52..f875e0e 100644
--- a/kqemu.c
+++ b/kqemu.c
@@ -159,6 +159,8 @@ static void kqemu_update_cpuid(CPUState *env)
        accelerated code */
 }
 
+QEMUAccel kqemu_accel;
+
 int kqemu_start(void)
 {
     struct kqemu_init init;
@@ -240,6 +242,7 @@ int kqemu_start(void)
     }
     nb_pages_to_flush = 0;
     nb_ram_pages_to_update = 0;
+    register_qemu_accel(&kqemu_accel);
     return 0;
 }
 
@@ -249,6 +252,20 @@ void kqemu_init_env(CPUState *env)
     env->kqemu_enabled = kqemu_allowed;
 }
 
+void kqemu_cpu_interrupt(CPUState *env)
+{
+#if defined(_WIN32) && KQEMU_VERSION >= 0x010101
+    /* cancelling the I/O request causes KQEMU to finish executing the
+       current block and successfully returning. */
+    CancelIo(kqemu_fd);
+#endif
+}
+
+QEMUAccel kqemu_accel = {
+    .cpu_interrupt = kqemu_cpu_interrupt,
+};
+
+
 void kqemu_flush_page(CPUState *env, target_ulong addr)
 {
 #if defined(DEBUG)
@@ -906,14 +923,4 @@ int kqemu_cpu_exec(CPUState *env)
     }
     return 0;
 }
-
-void kqemu_cpu_interrupt(CPUState *env)
-{
-#if defined(_WIN32) && KQEMU_VERSION >= 0x010101
-    /* cancelling the I/O request causes KQEMU to finish executing the
-       current block and successfully returning. */
-    CancelIo(kqemu_fd);
-#endif
-}
-
 #endif
diff --git a/vl.c b/vl.c
index 5999b37..26c1677 100644
--- a/vl.c
+++ b/vl.c
@@ -239,6 +239,7 @@ struct drive_opt {
 static CPUState *cur_cpu;
 static CPUState *next_cpu;
 static int event_pending = 1;
+QEMUAccel *current_accel;
 
 #define TFR(expr) do { if ((expr) != -1) break; } while (errno == EINTR)
 
@@ -1199,11 +1200,6 @@ static void host_alarm_handler(int host_signum)
         if (env) {
             /* stop the currently executing cpu because a timer occured */
             cpu_interrupt(env, CPU_INTERRUPT_EXIT);
-#ifdef USE_KQEMU
-            if (env->kqemu_enabled) {
-                kqemu_cpu_interrupt(env);
-            }
-#endif
         }
         event_pending = 1;
     }
-- 
1.5.5

[Qemu-devel] [PATCH 04/13] [PATCH] init env made accel driver

[Glauber Costa]

---
 exec-all.h            |    8 +++++++-
 kqemu.c               |    1 +
 target-i386/helper2.c |    4 +---
 3 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/exec-all.h b/exec-all.h
index 7b2d97d..9e211dc 100644
--- a/exec-all.h
+++ b/exec-all.h
@@ -580,6 +580,7 @@ static inline target_ulong get_phys_addr_code(CPUState *env1, target_ulong addr)
 
 typedef struct QEMUAccel {
     void (*cpu_interrupt)(CPUState *env);
+    void (*init_env)(CPUState *env);
 } QEMUAccel;
 
 extern QEMUAccel *current_accel;
@@ -595,10 +596,15 @@ static inline void accel_cpu_interrupt(CPUState *env)
         current_accel->cpu_interrupt(env);
 }
 
+static inline void accel_init_env(CPUState *env)
+{
+    if (current_accel && current_accel->init_env)
+        current_accel->init_env(env);
+}
+
 #ifdef USE_KQEMU
 #define KQEMU_MODIFY_PAGE_MASK (0xff & ~(VGA_DIRTY_FLAG | CODE_DIRTY_FLAG))
 
-int kqemu_init(CPUState *env);
 int kqemu_cpu_exec(CPUState *env);
 void kqemu_flush_page(CPUState *env, target_ulong addr);
 void kqemu_flush(CPUState *env, int global);
diff --git a/kqemu.c b/kqemu.c
index f875e0e..e0422de 100644
--- a/kqemu.c
+++ b/kqemu.c
@@ -263,6 +263,7 @@ void kqemu_cpu_interrupt(CPUState *env)
 
 QEMUAccel kqemu_accel = {
     .cpu_interrupt = kqemu_cpu_interrupt,
+    .init_env = kqemu_init_env,
 };
 
 
diff --git a/target-i386/helper2.c b/target-i386/helper2.c
index 1c0fcdb..b633814 100644
--- a/target-i386/helper2.c
+++ b/target-i386/helper2.c
@@ -112,9 +112,7 @@ CPUX86State *cpu_x86_init(const char *cpu_model)
         return NULL;
     }
     cpu_reset(env);
-#ifdef USE_KQEMU
-    kqemu_init_env(env);
-#endif
+    accel_init_env(env);
     return env;
 }
 
-- 
1.5.5

[Qemu-devel] [PATCH 05/13] [PATCH] wrap cache flushing functions into accel drivers

[Glauber Costa]

---
 exec-all.h |   16 ++++++++++++++--
 exec.c     |   12 ++----------
 kqemu.c    |   15 +++++++++------
 3 files changed, 25 insertions(+), 18 deletions(-)

diff --git a/exec-all.h b/exec-all.h
index 9e211dc..bfc6576 100644
--- a/exec-all.h
+++ b/exec-all.h
@@ -581,6 +581,8 @@ static inline target_ulong get_phys_addr_code(CPUState *env1, target_ulong addr)
 typedef struct QEMUAccel {
     void (*cpu_interrupt)(CPUState *env);
     void (*init_env)(CPUState *env);
+    void (*flush_cache)(CPUState *env, int global);
+    void (*flush_page)(CPUState *env, target_ulong addr);
 } QEMUAccel;
 
 extern QEMUAccel *current_accel;
@@ -602,12 +604,22 @@ static inline void accel_init_env(CPUState *env)
         current_accel->init_env(env);
 }
 
+static inline void accel_flush_cache(CPUState *env, int global)
+{
+    if (current_accel && current_accel->flush_cache)
+        current_accel->flush_cache(env, global);
+}
+
+static inline void accel_flush_page(CPUState *env, target_ulong addr)
+{
+    if (current_accel && current_accel->flush_page)
+        current_accel->flush_page(env, addr);
+}
+
 #ifdef USE_KQEMU
 #define KQEMU_MODIFY_PAGE_MASK (0xff & ~(VGA_DIRTY_FLAG | CODE_DIRTY_FLAG))
 
 int kqemu_cpu_exec(CPUState *env);
-void kqemu_flush_page(CPUState *env, target_ulong addr);
-void kqemu_flush(CPUState *env, int global);
 void kqemu_set_notdirty(CPUState *env, ram_addr_t ram_addr);
 void kqemu_modify_page(CPUState *env, ram_addr_t ram_addr);
 void kqemu_record_dump(void);
diff --git a/exec.c b/exec.c
index 73360d3..5b093a3 100644
--- a/exec.c
+++ b/exec.c
@@ -1438,11 +1438,7 @@ void tlb_flush(CPUState *env, int flush_global)
 #if !defined(CONFIG_SOFTMMU)
     munmap((void *)MMAP_AREA_START, MMAP_AREA_END - MMAP_AREA_START);
 #endif
-#ifdef USE_KQEMU
-    if (env->kqemu_enabled) {
-        kqemu_flush(env, flush_global);
-    }
-#endif
+    accel_flush_cache(env, flush_global);
     tlb_flush_count++;
 }
 
@@ -1488,11 +1484,7 @@ void tlb_flush_page(CPUState *env, target_ulong addr)
     if (addr < MMAP_AREA_END)
         munmap((void *)addr, TARGET_PAGE_SIZE);
 #endif
-#ifdef USE_KQEMU
-    if (env->kqemu_enabled) {
-        kqemu_flush_page(env, addr);
-    }
-#endif
+    accel_flush_page(env, addr);
 }
 
 /* update the TLBs so that writes to code in the virtual page 'addr'
diff --git a/kqemu.c b/kqemu.c
index e0422de..524c74d 100644
--- a/kqemu.c
+++ b/kqemu.c
@@ -261,12 +261,6 @@ void kqemu_cpu_interrupt(CPUState *env)
 #endif
 }
 
-QEMUAccel kqemu_accel = {
-    .cpu_interrupt = kqemu_cpu_interrupt,
-    .init_env = kqemu_init_env,
-};
-
-
 void kqemu_flush_page(CPUState *env, target_ulong addr)
 {
 #if defined(DEBUG)
@@ -290,6 +284,15 @@ void kqemu_flush(CPUState *env, int global)
     nb_pages_to_flush = KQEMU_FLUSH_ALL;
 }
 
+QEMUAccel kqemu_accel = {
+    .cpu_interrupt = kqemu_cpu_interrupt,
+    .init_env = kqemu_init_env,
+    .flush_cache = kqemu_flush,
+    .flush_page = kqemu_flush_page,
+};
+
+
+
 void kqemu_set_notdirty(CPUState *env, ram_addr_t ram_addr)
 {
 #ifdef DEBUG
-- 
1.5.5

[Qemu-devel] [PATCH 06/13] [PATCH] turn info kqemu into generic info accelerator

[Glauber Costa]

---
 exec-all.h |    8 ++++++++
 kqemu.c    |   24 ++++++++++++++++++++++++
 monitor.c  |   36 +++++++++++++-----------------------
 3 files changed, 45 insertions(+), 23 deletions(-)

diff --git a/exec-all.h b/exec-all.h
index bfc6576..f1bd7ae 100644
--- a/exec-all.h
+++ b/exec-all.h
@@ -583,6 +583,7 @@ typedef struct QEMUAccel {
     void (*init_env)(CPUState *env);
     void (*flush_cache)(CPUState *env, int global);
     void (*flush_page)(CPUState *env, target_ulong addr);
+    int (*info)(CPUState *env, char *buf);
 } QEMUAccel;
 
 extern QEMUAccel *current_accel;
@@ -616,6 +617,13 @@ static inline void accel_flush_page(CPUState *env, target_ulong addr)
         current_accel->flush_page(env, addr);
 }
 
+static inline int accel_info(CPUState *env, char *buf)
+{
+    if (current_accel && current_accel->info)
+        return current_accel->info(env, buf);
+    return 0;
+}
+
 #ifdef USE_KQEMU
 #define KQEMU_MODIFY_PAGE_MASK (0xff & ~(VGA_DIRTY_FLAG | CODE_DIRTY_FLAG))
 
diff --git a/kqemu.c b/kqemu.c
index 524c74d..451d1d4 100644
--- a/kqemu.c
+++ b/kqemu.c
@@ -284,11 +284,35 @@ void kqemu_flush(CPUState *env, int global)
     nb_pages_to_flush = KQEMU_FLUSH_ALL;
 }
 
+int kqemu_info(CPUState *env, char *buf)
+{
+    int val, len;
+    val = 0;
+    val = env->kqemu_enabled;
+    len = sprintf(buf, "kqemu support: ");
+    buf += len;
+
+    switch(val) {
+    default:
+        len += sprintf(buf, "present, but bogus value\n");
+        break;
+    case 1:
+        len += sprintf(buf, "enabled for user code\n");
+        break;
+    case 2:
+        len += sprintf(buf, "enabled for user and kernel code\n");
+        break;
+    }
+
+    return len;
+}
+
 QEMUAccel kqemu_accel = {
     .cpu_interrupt = kqemu_cpu_interrupt,
     .init_env = kqemu_init_env,
     .flush_cache = kqemu_flush,
     .flush_page = kqemu_flush_page,
+    .info = kqemu_info,
 };
 
 
diff --git a/monitor.c b/monitor.c
index 236b827..cb9faef 100644
--- a/monitor.c
+++ b/monitor.c
@@ -34,6 +34,7 @@
 #include "block.h"
 #include "audio/audio.h"
 #include "disas.h"
+#include "exec-all.h"
 #include <dirent.h>
 
 #ifdef CONFIG_PROFILER
@@ -1165,34 +1166,23 @@ static void mem_info(void)
 }
 #endif
 
-static void do_info_kqemu(void)
+#define MAX_BUF 1024
+static void do_info_accelerator(void)
 {
-#ifdef USE_KQEMU
+    char buf[MAX_BUF];
     CPUState *env;
-    int val;
-    val = 0;
+
     env = mon_get_cpu();
+
     if (!env) {
         term_printf("No cpu initialized yet");
         return;
     }
-    val = env->kqemu_enabled;
-    term_printf("kqemu support: ");
-    switch(val) {
-    default:
-    case 0:
-        term_printf("disabled\n");
-        break;
-    case 1:
-        term_printf("enabled for user code\n");
-        break;
-    case 2:
-        term_printf("enabled for user and kernel code\n");
-        break;
-    }
-#else
-    term_printf("kqemu support: not compiled\n");
-#endif
+
+    if (accel_info(env, buf))
+        term_printf(buf);
+    else
+        term_printf("No accelerator present\n");
 }
 
 #ifdef CONFIG_PROFILER
@@ -1422,8 +1412,8 @@ static term_cmd_t info_cmds[] = {
 #endif
     { "jit", "", do_info_jit,
       "", "show dynamic compiler info", },
-    { "kqemu", "", do_info_kqemu,
-      "", "show kqemu information", },
+    { "accelerator", "", do_info_accelerator,
+      "", "show accelerator information", },
     { "usb", "", usb_info,
       "", "show guest USB devices", },
     { "usbhost", "", usb_host_info,
-- 
1.5.5

[Qemu-devel] [PATCH 07/13] [PATCH] separate accelerator part of info profiler

[Glauber Costa]

---
 exec-all.h |    8 ++++++++
 kqemu.c    |   35 +++++++++++++++++++++++++++++++++++
 monitor.c  |   27 ++++++---------------------
 3 files changed, 49 insertions(+), 21 deletions(-)

diff --git a/exec-all.h b/exec-all.h
index f1bd7ae..689973d 100644
--- a/exec-all.h
+++ b/exec-all.h
@@ -584,6 +584,7 @@ typedef struct QEMUAccel {
     void (*flush_cache)(CPUState *env, int global);
     void (*flush_page)(CPUState *env, target_ulong addr);
     int (*info)(CPUState *env, char *buf);
+    int (*profile)(CPUState *env, char *buf);
 } QEMUAccel;
 
 extern QEMUAccel *current_accel;
@@ -624,6 +625,13 @@ static inline int accel_info(CPUState *env, char *buf)
     return 0;
 }
 
+static inline int accel_profile(CPUState *env, char *buf)
+{
+    if (current_accel && current_accel->profile)
+       return current_accel->profile(env, buf);
+    return 0;
+}
+
 #ifdef USE_KQEMU
 #define KQEMU_MODIFY_PAGE_MASK (0xff & ~(VGA_DIRTY_FLAG | CODE_DIRTY_FLAG))
 
diff --git a/kqemu.c b/kqemu.c
index 451d1d4..6d46dfb 100644
--- a/kqemu.c
+++ b/kqemu.c
@@ -51,6 +51,10 @@
 #include <fcntl.h>
 #include "kqemu.h"
 
+#ifdef CONFIG_PROFILER
+#include "qemu-timer.h" /* for ticks_per_sec */
+#endif
+
 /* compatibility stuff */
 #ifndef KQEMU_RET_SYSCALL
 #define KQEMU_RET_SYSCALL   0x0300 /* syscall insn */
@@ -307,12 +311,43 @@ int kqemu_info(CPUState *env, char *buf)
     return len;
 }
 
+int64_t kqemu_time;
+int64_t kqemu_exec_count;
+int64_t kqemu_ret_int_count;
+int64_t kqemu_ret_excp_count;
+int64_t kqemu_ret_intr_count;
+extern int64_t qemu_time;
+
+int kqemu_profile(CPUState *env, char *buf)
+{
+    int len = 0;
+#ifdef CONFIG_PROFILER
+    len = sprintf(buf, "kqemu time  %" PRId64 " (%0.3f %0.1f%%) count=%" PRId64
+                        " int=%" PRId64 " excp=%" PRId64 " intr=%" PRId64 "\n",
+                kqemu_time, kqemu_time / (double)ticks_per_sec,
+                kqemu_time / qemu_time * 100.0,
+                kqemu_exec_count,
+                kqemu_ret_int_count,
+                kqemu_ret_excp_count,
+                kqemu_ret_intr_count);
+
+    kqemu_time = 0;
+    kqemu_exec_count = 0;
+    kqemu_ret_int_count = 0;
+    kqemu_ret_excp_count = 0;
+    kqemu_ret_intr_count = 0;
+    kqemu_record_dump();
+#endif
+    return len;
+}
+
 QEMUAccel kqemu_accel = {
     .cpu_interrupt = kqemu_cpu_interrupt,
     .init_env = kqemu_init_env,
     .flush_cache = kqemu_flush,
     .flush_page = kqemu_flush_page,
     .info = kqemu_info,
+    .profile = kqemu_profile,
 };
 
 
diff --git a/monitor.c b/monitor.c
index cb9faef..2ee5b0c 100644
--- a/monitor.c
+++ b/monitor.c
@@ -1187,17 +1187,14 @@ static void do_info_accelerator(void)
 
 #ifdef CONFIG_PROFILER
 
-int64_t kqemu_time;
 int64_t qemu_time;
-int64_t kqemu_exec_count;
 int64_t dev_time;
-int64_t kqemu_ret_int_count;
-int64_t kqemu_ret_excp_count;
-int64_t kqemu_ret_intr_count;
-
 static void do_info_profile(void)
 {
     int64_t total;
+    char buf[MAX_BUF];
+    CPUState *env = mon_get_cpu();
+
     total = qemu_time;
     if (total == 0)
         total = 1;
@@ -1205,24 +1202,12 @@ static void do_info_profile(void)
                 dev_time, dev_time / (double)ticks_per_sec);
     term_printf("qemu time   %" PRId64 " (%0.3f)\n",
                 qemu_time, qemu_time / (double)ticks_per_sec);
-    term_printf("kqemu time  %" PRId64 " (%0.3f %0.1f%%) count=%" PRId64 " int=%" PRId64 " excp=%" PRId64 " intr=%" PRId64 "\n",
-                kqemu_time, kqemu_time / (double)ticks_per_sec,
-                kqemu_time / (double)total * 100.0,
-                kqemu_exec_count,
-                kqemu_ret_int_count,
-                kqemu_ret_excp_count,
-                kqemu_ret_intr_count);
+    if (accel_profile(env, buf))
+        term_printf(buf);
     qemu_time = 0;
-    kqemu_time = 0;
-    kqemu_exec_count = 0;
     dev_time = 0;
-    kqemu_ret_int_count = 0;
-    kqemu_ret_excp_count = 0;
-    kqemu_ret_intr_count = 0;
-#ifdef USE_KQEMU
-    kqemu_record_dump();
-#endif
 }
+
 #else
 static void do_info_profile(void)
 {
-- 
1.5.5

[Qemu-devel] [PATCH 08/13] [PATCH] move kqemu externs to kqemu.h

[Glauber Costa]

---
 cpu-all.h |    5 -----
 kqemu.h   |    6 ++++++
 2 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/cpu-all.h b/cpu-all.h
index 7e77f76..5336a29 100644
--- a/cpu-all.h
+++ b/cpu-all.h
@@ -1053,14 +1053,9 @@ static inline int64_t profile_getclock(void)
     return cpu_get_real_ticks();
 }
 
-extern int64_t kqemu_time, kqemu_time_start;
 extern int64_t qemu_time, qemu_time_start;
 extern int64_t tlb_flush_time;
-extern int64_t kqemu_exec_count;
 extern int64_t dev_time;
-extern int64_t kqemu_ret_int_count;
-extern int64_t kqemu_ret_excp_count;
-extern int64_t kqemu_ret_intr_count;
 
 extern int64_t dyngen_tb_count1;
 extern int64_t dyngen_tb_count;
diff --git a/kqemu.h b/kqemu.h
index 7b43057..88156c1 100644
--- a/kqemu.h
+++ b/kqemu.h
@@ -26,6 +26,12 @@
 
 #define KQEMU_VERSION 0x010300
 
+extern int64_t kqemu_time, kqemu_time_start;
+extern int64_t kqemu_exec_count;
+extern int64_t kqemu_ret_int_count;
+extern int64_t kqemu_ret_excp_count;
+extern int64_t kqemu_ret_intr_count;
+
 struct kqemu_segment_cache {
     uint32_t selector;
     unsigned long base;
-- 
1.5.5

[Qemu-devel] [PATCH 09/13] [PATCH] move disabling code to kqemu.c instead of vl.c

[Glauber Costa]

this is for the case in which we run more than one cpu
---
 kqemu.c |    3 ++-
 vl.c    |    4 ----
 2 files changed, 2 insertions(+), 5 deletions(-)

diff --git a/kqemu.c b/kqemu.c
index 6d46dfb..94366ec 100644
--- a/kqemu.c
+++ b/kqemu.c
@@ -164,6 +164,7 @@ static void kqemu_update_cpuid(CPUState *env)
 }
 
 QEMUAccel kqemu_accel;
+extern int smp_cpus;
 
 int kqemu_start(void)
 {
@@ -173,7 +174,7 @@ int kqemu_start(void)
     DWORD temp;
 #endif
 
-    if (!kqemu_allowed)
+    if (!kqemu_allowed || smp_cpus > 1)
         return -1;
 
 #ifdef _WIN32
diff --git a/vl.c b/vl.c
index 26c1677..8104e33 100644
--- a/vl.c
+++ b/vl.c
@@ -8357,10 +8357,6 @@ int main(int argc, char **argv)
         exit(1);
     }
 
-#ifdef USE_KQEMU
-    if (smp_cpus > 1)
-        kqemu_allowed = 0;
-#endif
     linux_boot = (kernel_filename != NULL);
     net_boot = (boot_devices_bitmap >> ('n' - 'a')) & 0xF;
 
-- 
1.5.5

[Qemu-devel] [PATCH 10/13] [PATCH] set_notdirty goes through accel wrapper

[Glauber Costa]

---
 exec-all.h |    8 +++++++-
 exec.c     |   18 +++++++-----------
 kqemu.c    |   23 +++++++++++------------
 3 files changed, 25 insertions(+), 24 deletions(-)

diff --git a/exec-all.h b/exec-all.h
index 689973d..ed96a22 100644
--- a/exec-all.h
+++ b/exec-all.h
@@ -585,6 +585,7 @@ typedef struct QEMUAccel {
     void (*flush_page)(CPUState *env, target_ulong addr);
     int (*info)(CPUState *env, char *buf);
     int (*profile)(CPUState *env, char *buf);
+    void (*set_notdirty)(ram_addr_t addr);
 } QEMUAccel;
 
 extern QEMUAccel *current_accel;
@@ -632,11 +633,16 @@ static inline int accel_profile(CPUState *env, char *buf)
     return 0;
 }
 
+static inline void accel_set_notdirty(target_ulong addr)
+{
+    if (current_accel && current_accel->set_notdirty)
+        current_accel->set_notdirty(addr);
+}
+
 #ifdef USE_KQEMU
 #define KQEMU_MODIFY_PAGE_MASK (0xff & ~(VGA_DIRTY_FLAG | CODE_DIRTY_FLAG))
 
 int kqemu_cpu_exec(CPUState *env);
-void kqemu_set_notdirty(CPUState *env, ram_addr_t ram_addr);
 void kqemu_modify_page(CPUState *env, ram_addr_t ram_addr);
 void kqemu_record_dump(void);
 
diff --git a/exec.c b/exec.c
index 5b093a3..6d05f75 100644
--- a/exec.c
+++ b/exec.c
@@ -1531,18 +1531,14 @@ void cpu_physical_memory_reset_dirty(ram_addr_t start, ram_addr_t end,
     if (length == 0)
         return;
     len = length >> TARGET_PAGE_BITS;
-#ifdef USE_KQEMU
-    /* XXX: should not depend on cpu context */
-    env = first_cpu;
-    if (env->kqemu_enabled) {
-        ram_addr_t addr;
-        addr = start;
-        for(i = 0; i < len; i++) {
-            kqemu_set_notdirty(env, addr);
-            addr += TARGET_PAGE_SIZE;
-        }
+
+    ram_addr_t addr;
+    addr = start;
+    for(i = 0; i < len; i++) {
+        accel_set_notdirty(addr);
+        addr += TARGET_PAGE_SIZE;
     }
-#endif
+
     mask = ~dirty_flags;
     p = phys_ram_dirty + (start >> TARGET_PAGE_BITS);
     for(i = 0; i < len; i++)
diff --git a/kqemu.c b/kqemu.c
index 94366ec..44c1a55 100644
--- a/kqemu.c
+++ b/kqemu.c
@@ -342,18 +342,7 @@ int kqemu_profile(CPUState *env, char *buf)
     return len;
 }
 
-QEMUAccel kqemu_accel = {
-    .cpu_interrupt = kqemu_cpu_interrupt,
-    .init_env = kqemu_init_env,
-    .flush_cache = kqemu_flush,
-    .flush_page = kqemu_flush_page,
-    .info = kqemu_info,
-    .profile = kqemu_profile,
-};
-
-
-
-void kqemu_set_notdirty(CPUState *env, ram_addr_t ram_addr)
+void kqemu_set_notdirty(ram_addr_t ram_addr)
 {
 #ifdef DEBUG
     if (loglevel & CPU_LOG_INT) {
@@ -369,6 +358,16 @@ void kqemu_set_notdirty(CPUState *env, ram_addr_t ram_addr)
         ram_pages_to_update[nb_ram_pages_to_update++] = ram_addr;
 }
 
+QEMUAccel kqemu_accel = {
+    .cpu_interrupt = kqemu_cpu_interrupt,
+    .init_env = kqemu_init_env,
+    .flush_cache = kqemu_flush,
+    .flush_page = kqemu_flush_page,
+    .info = kqemu_info,
+    .profile = kqemu_profile,
+    .set_notdirty = kqemu_set_notdirty,
+};
+
 static void kqemu_reset_modified_ram_pages(void)
 {
     int i;
-- 
1.5.5

[Qemu-devel] [PATCH 11/13] [PATCH] wrap modify_page through accel calls

[Glauber Costa]

---
 exec-all.h |    8 +++++++-
 exec.c     |   24 +++++++++---------------
 kqemu.c    |   26 +++++++++++++++-----------
 3 files changed, 31 insertions(+), 27 deletions(-)

diff --git a/exec-all.h b/exec-all.h
index ed96a22..04112e0 100644
--- a/exec-all.h
+++ b/exec-all.h
@@ -586,6 +586,7 @@ typedef struct QEMUAccel {
     int (*info)(CPUState *env, char *buf);
     int (*profile)(CPUState *env, char *buf);
     void (*set_notdirty)(ram_addr_t addr);
+    void (*modify_page)(ram_addr_t addr, int dirty_flags);
 } QEMUAccel;
 
 extern QEMUAccel *current_accel;
@@ -639,11 +640,16 @@ static inline void accel_set_notdirty(target_ulong addr)
         current_accel->set_notdirty(addr);
 }
 
+static inline void accel_modify_page(target_ulong addr, int dirty_flags)
+{
+    if (current_accel && current_accel->modify_page)
+        current_accel->modify_page(addr, dirty_flags);
+}
+
 #ifdef USE_KQEMU
 #define KQEMU_MODIFY_PAGE_MASK (0xff & ~(VGA_DIRTY_FLAG | CODE_DIRTY_FLAG))
 
 int kqemu_cpu_exec(CPUState *env);
-void kqemu_modify_page(CPUState *env, ram_addr_t ram_addr);
 void kqemu_record_dump(void);
 
 static inline int kqemu_is_ok(CPUState *env)
diff --git a/exec.c b/exec.c
index 6d05f75..92f1552 100644
--- a/exec.c
+++ b/exec.c
@@ -2185,11 +2185,9 @@ static void notdirty_mem_writeb(void *opaque, target_phys_addr_t addr, uint32_t
 #endif
     }
     stb_p((uint8_t *)(long)addr, val);
-#ifdef USE_KQEMU
-    if (cpu_single_env->kqemu_enabled &&
-        (dirty_flags & KQEMU_MODIFY_PAGE_MASK) != KQEMU_MODIFY_PAGE_MASK)
-        kqemu_modify_page(cpu_single_env, ram_addr);
-#endif
+
+    accel_modify_page(ram_addr, dirty_flags);
+
     dirty_flags |= (0xff & ~CODE_DIRTY_FLAG);
     phys_ram_dirty[ram_addr >> TARGET_PAGE_BITS] = dirty_flags;
     /* we remove the notdirty callback only if the code has been
@@ -2211,11 +2209,9 @@ static void notdirty_mem_writew(void *opaque, target_phys_addr_t addr, uint32_t
 #endif
     }
     stw_p((uint8_t *)(long)addr, val);
-#ifdef USE_KQEMU
-    if (cpu_single_env->kqemu_enabled &&
-        (dirty_flags & KQEMU_MODIFY_PAGE_MASK) != KQEMU_MODIFY_PAGE_MASK)
-        kqemu_modify_page(cpu_single_env, ram_addr);
-#endif
+
+    accel_modify_page(ram_addr, dirty_flags);
+
     dirty_flags |= (0xff & ~CODE_DIRTY_FLAG);
     phys_ram_dirty[ram_addr >> TARGET_PAGE_BITS] = dirty_flags;
     /* we remove the notdirty callback only if the code has been
@@ -2237,11 +2233,9 @@ static void notdirty_mem_writel(void *opaque, target_phys_addr_t addr, uint32_t
 #endif
     }
     stl_p((uint8_t *)(long)addr, val);
-#ifdef USE_KQEMU
-    if (cpu_single_env->kqemu_enabled &&
-        (dirty_flags & KQEMU_MODIFY_PAGE_MASK) != KQEMU_MODIFY_PAGE_MASK)
-        kqemu_modify_page(cpu_single_env, ram_addr);
-#endif
+
+    accel_modify_page(ram_addr, dirty_flags);
+
     dirty_flags |= (0xff & ~CODE_DIRTY_FLAG);
     phys_ram_dirty[ram_addr >> TARGET_PAGE_BITS] = dirty_flags;
     /* we remove the notdirty callback only if the code has been
diff --git a/kqemu.c b/kqemu.c
index 44c1a55..7e24bb7 100644
--- a/kqemu.c
+++ b/kqemu.c
@@ -358,16 +358,6 @@ void kqemu_set_notdirty(ram_addr_t ram_addr)
         ram_pages_to_update[nb_ram_pages_to_update++] = ram_addr;
 }
 
-QEMUAccel kqemu_accel = {
-    .cpu_interrupt = kqemu_cpu_interrupt,
-    .init_env = kqemu_init_env,
-    .flush_cache = kqemu_flush,
-    .flush_page = kqemu_flush_page,
-    .info = kqemu_info,
-    .profile = kqemu_profile,
-    .set_notdirty = kqemu_set_notdirty,
-};
-
 static void kqemu_reset_modified_ram_pages(void)
 {
     int i;
@@ -380,7 +370,7 @@ static void kqemu_reset_modified_ram_pages(void)
     nb_modified_ram_pages = 0;
 }
 
-void kqemu_modify_page(CPUState *env, ram_addr_t ram_addr)
+void kqemu_modify_page(ram_addr_t ram_addr, int dirty_flags)
 {
     unsigned long page_index;
     int ret;
@@ -388,6 +378,8 @@ void kqemu_modify_page(CPUState *env, ram_addr_t ram_addr)
     DWORD temp;
 #endif
 
+    if ((dirty_flags & KQEMU_MODIFY_PAGE_MASK) != KQEMU_MODIFY_PAGE_MASK)
+        return;
     page_index = ram_addr >> TARGET_PAGE_BITS;
     if (!modified_ram_pages_table[page_index]) {
 #if 0
@@ -411,6 +403,18 @@ void kqemu_modify_page(CPUState *env, ram_addr_t ram_addr)
     }
 }
 
+QEMUAccel kqemu_accel = {
+    .cpu_interrupt = kqemu_cpu_interrupt,
+    .init_env = kqemu_init_env,
+    .flush_cache = kqemu_flush,
+    .flush_page = kqemu_flush_page,
+    .info = kqemu_info,
+    .profile = kqemu_profile,
+    .set_notdirty = kqemu_set_notdirty,
+    .modify_page = kqemu_modify_page,
+};
+
+
 struct fpstate {
     uint16_t fpuc;
     uint16_t dummy1;
-- 
1.5.5

[Qemu-devel] [PATCH 12/13] [PATCH] remove kqemu reference from hw/pc.c

[Glauber Costa]

Instead, route cpu_get_ticks through accel driver.
---
 exec-all.h |   11 +++++++++++
 hw/pc.c    |   13 ++-----------
 kqemu.c    |    4 ++++
 3 files changed, 17 insertions(+), 11 deletions(-)

diff --git a/exec-all.h b/exec-all.h
index 04112e0..f62ff38 100644
--- a/exec-all.h
+++ b/exec-all.h
@@ -587,6 +587,7 @@ typedef struct QEMUAccel {
     int (*profile)(CPUState *env, char *buf);
     void (*set_notdirty)(ram_addr_t addr);
     void (*modify_page)(ram_addr_t addr, int dirty_flags);
+    uint64_t (*get_real_ticks)(void);
 } QEMUAccel;
 
 extern QEMUAccel *current_accel;
@@ -646,6 +647,16 @@ static inline void accel_modify_page(target_ulong addr, int dirty_flags)
         current_accel->modify_page(addr, dirty_flags);
 }
 
+int64_t cpu_get_ticks(void);
+
+static inline uint64_t accel_get_real_ticks(void)
+{
+    if (current_accel && current_accel->get_real_ticks)
+       return current_accel->get_real_ticks();
+    return cpu_get_ticks();
+}
+
+
 #ifdef USE_KQEMU
 #define KQEMU_MODIFY_PAGE_MASK (0xff & ~(VGA_DIRTY_FLAG | CODE_DIRTY_FLAG))
 
diff --git a/hw/pc.c b/hw/pc.c
index c92384c..43ff2f2 100644
--- a/hw/pc.c
+++ b/hw/pc.c
@@ -32,6 +32,7 @@
 #include "smbus.h"
 #include "boards.h"
 #include "console.h"
+#include "exec-all.h"
 
 /* output Bochs bios info messages */
 //#define DEBUG_BIOS
@@ -73,17 +74,7 @@ static void ioportF0_write(void *opaque, uint32_t addr, uint32_t data)
 /* TSC handling */
 uint64_t cpu_get_tsc(CPUX86State *env)
 {
-    /* Note: when using kqemu, it is more logical to return the host TSC
-       because kqemu does not trap the RDTSC instruction for
-       performance reasons */
-#if USE_KQEMU
-    if (env->kqemu_enabled) {
-        return cpu_get_real_ticks();
-    } else
-#endif
-    {
-        return cpu_get_ticks();
-    }
+    return accel_get_real_ticks();
 }
 
 /* SMM support */
diff --git a/kqemu.c b/kqemu.c
index 7e24bb7..fbd8b66 100644
--- a/kqemu.c
+++ b/kqemu.c
@@ -412,6 +412,10 @@ QEMUAccel kqemu_accel = {
     .profile = kqemu_profile,
     .set_notdirty = kqemu_set_notdirty,
     .modify_page = kqemu_modify_page,
+    /* Note: when using kqemu, it is more logical to return the host TSC
+       because kqemu does not trap the RDTSC instruction for
+       performance reasons */
+    .get_real_ticks = cpu_get_real_ticks,
 };
 
 
-- 
1.5.5

[Qemu-devel] [PATCH 13/13] [PATCH] build list of available accelerators

[Glauber Costa]

instead of hardcoding kqemu_start() in exec.c, which would require
such a hack for all available accelerators, semantics of register_qemu_accel()
is changed a little bit. It only builds a list of available accelerators.
The last one registered is the first tried.

This is a temporary solution, since we don't control exactly the order in which
things are loaded by the constructor attributes. The final goal is to have command
line switches and priority lists to determine that.

"info accelerator" is changed to accomodate it. It now prints a list of available
accelerators, and only if one of them is active, a detailed description of it is printed.
---
 exec-all.h |   43 +++++++++++++++++++++++++++++++++++++++++--
 exec.c     |    4 +---
 kqemu.c    |   11 +++++++++--
 monitor.c  |   18 ++++++++++++++++--
 vl.c       |    1 +
 5 files changed, 68 insertions(+), 9 deletions(-)

diff --git a/exec-all.h b/exec-all.h
index f62ff38..eca5cdb 100644
--- a/exec-all.h
+++ b/exec-all.h
@@ -579,8 +579,10 @@ static inline target_ulong get_phys_addr_code(CPUState *env1, target_ulong addr)
 #endif
 
 typedef struct QEMUAccel {
+    char *name;
     void (*cpu_interrupt)(CPUState *env);
     void (*init_env)(CPUState *env);
+    int (*start)(void);
     void (*flush_cache)(CPUState *env, int global);
     void (*flush_page)(CPUState *env, target_ulong addr);
     int (*info)(CPUState *env, char *buf);
@@ -590,11 +592,33 @@ typedef struct QEMUAccel {
     uint64_t (*get_real_ticks)(void);
 } QEMUAccel;
 
+typedef struct QEMUCont {
+    QEMUAccel *acc;
+    int active;
+    struct QEMUCont *next;
+} QEMUCont;
+
 extern QEMUAccel *current_accel;
+extern QEMUCont *head;
+void *qemu_mallocz(size_t size);
+
+static inline int register_qemu_accel(QEMUAccel *accel)
+{
+    QEMUCont *new;
+
+    new = qemu_mallocz(sizeof(*head));
+
+    new->acc = accel;
+    new->active = 0;
+    new->next = head;
+    head = new;
+
+    return 0;
+}
 
-static inline void register_qemu_accel(QEMUAccel *accel)
+static inline QEMUCont *get_accel_head(void)
 {
-    current_accel = accel;
+    return head;
 }
 
 static inline void accel_cpu_interrupt(CPUState *env)
@@ -603,6 +627,21 @@ static inline void accel_cpu_interrupt(CPUState *env)
         current_accel->cpu_interrupt(env);
 }
 
+static inline void accel_start(void)
+{
+    /* The top accelerator in the list gets tried first, but if it fails,
+     * keep trying until one of them succeeds or we exhaust the list */
+    QEMUCont *tmp = head;
+    while (tmp) {
+        if (tmp->acc && tmp->acc->start && (!(tmp->acc->start())) ) {
+            tmp->active = 1;
+            current_accel = tmp->acc;
+            break;
+        }
+        tmp = tmp->next; 
+    }
+}
+
 static inline void accel_init_env(CPUState *env)
 {
     if (current_accel && current_accel->init_env)
diff --git a/exec.c b/exec.c
index 92f1552..c885f7d 100644
--- a/exec.c
+++ b/exec.c
@@ -334,9 +334,7 @@ void exec_init(void)
     code_gen_ptr = code_gen_buffer;
     page_init();
     io_mem_init();
-#ifdef USE_KQEMU
-    kqemu_start();
-#endif
+    accel_start();
 }
 
 void cpu_exec_init(CPUState *env)
diff --git a/kqemu.c b/kqemu.c
index fbd8b66..996538d 100644
--- a/kqemu.c
+++ b/kqemu.c
@@ -163,7 +163,6 @@ static void kqemu_update_cpuid(CPUState *env)
        accelerated code */
 }
 
-QEMUAccel kqemu_accel;
 extern int smp_cpus;
 
 int kqemu_start(void)
@@ -247,7 +246,6 @@ int kqemu_start(void)
     }
     nb_pages_to_flush = 0;
     nb_ram_pages_to_update = 0;
-    register_qemu_accel(&kqemu_accel);
     return 0;
 }
 
@@ -404,8 +402,10 @@ void kqemu_modify_page(ram_addr_t ram_addr, int dirty_flags)
 }
 
 QEMUAccel kqemu_accel = {
+    .name = "kqemu",
     .cpu_interrupt = kqemu_cpu_interrupt,
     .init_env = kqemu_init_env,
+    .start = kqemu_start,
     .flush_cache = kqemu_flush,
     .flush_page = kqemu_flush_page,
     .info = kqemu_info,
@@ -418,6 +418,13 @@ QEMUAccel kqemu_accel = {
     .get_real_ticks = cpu_get_real_ticks,
 };
 
+static void __attribute__((constructor)) register_kqemu(void)
+{
+    if (register_qemu_accel(&kqemu_accel) < 0)
+        fprintf(logfile, "kqemu: could not register accelerator \n");
+}
+
+
 
 struct fpstate {
     uint16_t fpuc;
diff --git a/monitor.c b/monitor.c
index 2ee5b0c..49efa2d 100644
--- a/monitor.c
+++ b/monitor.c
@@ -1166,6 +1166,18 @@ static void mem_info(void)
 }
 #endif
 
+static int do_accel_do_list(void)
+{
+    QEMUCont *tmp;
+    int active = 0;
+    for (tmp= get_accel_head(); tmp != NULL; tmp = tmp->next)
+    {
+        term_printf("%c %s\n", tmp->active ? '*' : ' ', tmp->acc->name);
+        active |= tmp->active;
+    }
+    return active;
+}
+
 #define MAX_BUF 1024
 static void do_info_accelerator(void)
 {
@@ -1179,8 +1191,10 @@ static void do_info_accelerator(void)
         return;
     }
 
-    if (accel_info(env, buf))
-        term_printf(buf);
+    if (do_accel_do_list()) {
+        if (accel_info(env, buf))
+            term_printf(buf);
+    }
     else
         term_printf("No accelerator present\n");
 }
diff --git a/vl.c b/vl.c
index 8104e33..cd9af69 100644
--- a/vl.c
+++ b/vl.c
@@ -240,6 +240,7 @@ static CPUState *cur_cpu;
 static CPUState *next_cpu;
 static int event_pending = 1;
 QEMUAccel *current_accel;
+QEMUCont *head = NULL;
 
 #define TFR(expr) do { if ((expr) != -1) break; } while (errno == EINTR)
 
-- 
1.5.5