ptimer: Rename ptimer_init() to ptimer_init_with_bh()

Currently the ptimer design uses a QEMU bottom-half as its
mechanism for calling back into the device model using the
ptimer when the timer has expired. Unfortunately this design
is fatally flawed, because it means that there is a lag
between the ptimer updating its own state and the device
callback function updating device state, and guest accesses
to device registers between the two can return inconsistent
device state.

We want to replace the bottom-half design with one where
the guest device's callback is called either immediately
(when the ptimer triggers by timeout) or when the device
model code closes a transaction-begin/end section (when the
ptimer triggers because the device model changed the
ptimer's count value or other state). As the first step,
rename ptimer_init() to ptimer_init_with_bh(), to free up
the ptimer_init() name for the new API. We can then convert
all the ptimer users away from ptimer_init_with_bh() before
removing it entirely.

(Commit created with
 git grep -l ptimer_init | xargs sed -i -e 's/ptimer_init/ptimer_init_with_bh/'
and three overlong lines folded by hand.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20191008171740.9679-2-peter.maydell@linaro.org

hw/arm/musicpal.c

@@ -849,7 +849,7 @@ static void mv88w8618_timer_init(SysBusDevice *dev, mv88w8618_timer_state *s,
     s->freq = freq;
 
     bh = qemu_bh_new(mv88w8618_timer_tick, s);
-    s->ptimer = ptimer_init(bh, PTIMER_POLICY_DEFAULT);
+    s->ptimer = ptimer_init_with_bh(bh, PTIMER_POLICY_DEFAULT);
 }
 
 static uint64_t mv88w8618_pit_read(void *opaque, hwaddr offset,

hw/core/ptimer.c

@@ -358,7 +358,7 @@ const VMStateDescription vmstate_ptimer = {
     }
 };
 
-ptimer_state *ptimer_init(QEMUBH *bh, uint8_t policy_mask)
+ptimer_state *ptimer_init_with_bh(QEMUBH *bh, uint8_t policy_mask)
 {
     ptimer_state *s;
 

hw/dma/xilinx_axidma.c

@@ -552,7 +552,7 @@ static void xilinx_axidma_realize(DeviceState *dev, Error **errp)
 
         st->nr = i;
         st->bh = qemu_bh_new(timer_hit, st);
-        st->ptimer = ptimer_init(st->bh, PTIMER_POLICY_DEFAULT);
+        st->ptimer = ptimer_init_with_bh(st->bh, PTIMER_POLICY_DEFAULT);
         ptimer_set_freq(st->ptimer, s->freqhz);
     }
     return;

hw/m68k/mcf5206.c

@@ -141,7 +141,7 @@ static m5206_timer_state *m5206_timer_init(qemu_irq irq)
 
     s = g_new0(m5206_timer_state, 1);
     bh = qemu_bh_new(m5206_timer_trigger, s);
-    s->timer = ptimer_init(bh, PTIMER_POLICY_DEFAULT);
+    s->timer = ptimer_init_with_bh(bh, PTIMER_POLICY_DEFAULT);
     s->irq = irq;
     m5206_timer_reset(s);
     return s;

hw/m68k/mcf5208.c

@@ -192,7 +192,7 @@ static void mcf5208_sys_init(MemoryRegion *address_space, qemu_irq *pic)
     for (i = 0; i < 2; i++) {
         s = g_new0(m5208_timer_state, 1);
         bh = qemu_bh_new(m5208_timer_trigger, s);
-        s->timer = ptimer_init(bh, PTIMER_POLICY_DEFAULT);
+        s->timer = ptimer_init_with_bh(bh, PTIMER_POLICY_DEFAULT);
         memory_region_init_io(&s->iomem, NULL, &m5208_timer_ops, s,
                               "m5208-timer", 0x00004000);
         memory_region_add_subregion(address_space, 0xfc080000 + 0x4000 * i,

hw/net/fsl_etsec/etsec.c

@@ -393,7 +393,7 @@ static void etsec_realize(DeviceState *dev, Error **errp)
 
 
     etsec->bh     = qemu_bh_new(etsec_timer_hit, etsec);
-    etsec->ptimer = ptimer_init(etsec->bh, PTIMER_POLICY_DEFAULT);
+    etsec->ptimer = ptimer_init_with_bh(etsec->bh, PTIMER_POLICY_DEFAULT);
     ptimer_set_freq(etsec->ptimer, 100);
 }
 

hw/net/lan9118.c

@@ -1350,7 +1350,7 @@ static void lan9118_realize(DeviceState *dev, Error **errp)
     s->txp = &s->tx_packet;
 
     bh = qemu_bh_new(lan9118_tick, s);
-    s->timer = ptimer_init(bh, PTIMER_POLICY_DEFAULT);
+    s->timer = ptimer_init_with_bh(bh, PTIMER_POLICY_DEFAULT);
     ptimer_set_freq(s->timer, 10000);
     ptimer_set_limit(s->timer, 0xffff, 1);
 }

hw/timer/allwinner-a10-pit.c

@@ -271,7 +271,7 @@ static void a10_pit_init(Object *obj)
         tc->container = s;
         tc->index = i;
         bh[i] = qemu_bh_new(a10_pit_timer_cb, tc);
-        s->timer[i] = ptimer_init(bh[i], PTIMER_POLICY_DEFAULT);
+        s->timer[i] = ptimer_init_with_bh(bh[i], PTIMER_POLICY_DEFAULT);
     }
 }
 

hw/timer/altera_timer.c

@@ -184,7 +184,7 @@ static void altera_timer_realize(DeviceState *dev, Error **errp)
     }
 
     t->bh = qemu_bh_new(timer_hit, t);
-    t->ptimer = ptimer_init(t->bh, PTIMER_POLICY_DEFAULT);
+    t->ptimer = ptimer_init_with_bh(t->bh, PTIMER_POLICY_DEFAULT);
     ptimer_set_freq(t->ptimer, t->freq_hz);
 
     memory_region_init_io(&t->mmio, OBJECT(t), &timer_ops, t,

hw/timer/arm_mptimer.c

@@ -228,7 +228,7 @@ static void arm_mptimer_reset(DeviceState *dev)
     }
 }
 
-static void arm_mptimer_init(Object *obj)
+static void arm_mptimer_init_with_bh(Object *obj)
 {
     ARMMPTimerState *s = ARM_MPTIMER(obj);
 
@@ -261,7 +261,7 @@ static void arm_mptimer_realize(DeviceState *dev, Error **errp)
     for (i = 0; i < s->num_cpu; i++) {
         TimerBlock *tb = &s->timerblock[i];
         QEMUBH *bh = qemu_bh_new(timerblock_tick, tb);
-        tb->timer = ptimer_init(bh, PTIMER_POLICY);
+        tb->timer = ptimer_init_with_bh(bh, PTIMER_POLICY);
         sysbus_init_irq(sbd, &tb->irq);
         memory_region_init_io(&tb->iomem, OBJECT(s), &timerblock_ops, tb,
                               "arm_mptimer_timerblock", 0x20);
@@ -311,7 +311,7 @@ static const TypeInfo arm_mptimer_info = {
     .name          = TYPE_ARM_MPTIMER,
     .parent        = TYPE_SYS_BUS_DEVICE,
     .instance_size = sizeof(ARMMPTimerState),
-    .instance_init = arm_mptimer_init,
+    .instance_init = arm_mptimer_init_with_bh,
     .class_init    = arm_mptimer_class_init,
 };
 

hw/timer/arm_timer.c

@@ -173,7 +173,7 @@ static arm_timer_state *arm_timer_init(uint32_t freq)
     s->control = TIMER_CTRL_IE;
 
     bh = qemu_bh_new(arm_timer_tick, s);
-    s->timer = ptimer_init(bh, PTIMER_POLICY_DEFAULT);
+    s->timer = ptimer_init_with_bh(bh, PTIMER_POLICY_DEFAULT);
     vmstate_register(NULL, -1, &vmstate_arm_timer, s);
     return s;
 }

hw/timer/cmsdk-apb-dualtimer.c

@@ -453,7 +453,7 @@ static void cmsdk_apb_dualtimer_realize(DeviceState *dev, Error **errp)
         QEMUBH *bh = qemu_bh_new(cmsdk_dualtimermod_tick, m);
 
         m->parent = s;
-        m->timer = ptimer_init(bh,
+        m->timer = ptimer_init_with_bh(bh,
                                PTIMER_POLICY_WRAP_AFTER_ONE_PERIOD |
                                PTIMER_POLICY_TRIGGER_ONLY_ON_DECREMENT |
                                PTIMER_POLICY_NO_IMMEDIATE_RELOAD |

hw/timer/cmsdk-apb-timer.c

@@ -218,7 +218,7 @@ static void cmsdk_apb_timer_realize(DeviceState *dev, Error **errp)
     }
 
     bh = qemu_bh_new(cmsdk_apb_timer_tick, s);
-    s->timer = ptimer_init(bh,
+    s->timer = ptimer_init_with_bh(bh,
                            PTIMER_POLICY_WRAP_AFTER_ONE_PERIOD |
                            PTIMER_POLICY_TRIGGER_ONLY_ON_DECREMENT |
                            PTIMER_POLICY_NO_IMMEDIATE_RELOAD |

hw/timer/digic-timer.c

@@ -129,7 +129,7 @@ static void digic_timer_init(Object *obj)
 {
     DigicTimerState *s = DIGIC_TIMER(obj);
 
-    s->ptimer = ptimer_init(NULL, PTIMER_POLICY_DEFAULT);
+    s->ptimer = ptimer_init_with_bh(NULL, PTIMER_POLICY_DEFAULT);
 
     /*
      * FIXME: there is no documentation on Digic timer

hw/timer/etraxfs_timer.c

@@ -328,9 +328,9 @@ static void etraxfs_timer_realize(DeviceState *dev, Error **errp)
     t->bh_t0 = qemu_bh_new(timer0_hit, t);
     t->bh_t1 = qemu_bh_new(timer1_hit, t);
     t->bh_wd = qemu_bh_new(watchdog_hit, t);
-    t->ptimer_t0 = ptimer_init(t->bh_t0, PTIMER_POLICY_DEFAULT);
-    t->ptimer_t1 = ptimer_init(t->bh_t1, PTIMER_POLICY_DEFAULT);
-    t->ptimer_wd = ptimer_init(t->bh_wd, PTIMER_POLICY_DEFAULT);
+    t->ptimer_t0 = ptimer_init_with_bh(t->bh_t0, PTIMER_POLICY_DEFAULT);
+    t->ptimer_t1 = ptimer_init_with_bh(t->bh_t1, PTIMER_POLICY_DEFAULT);
+    t->ptimer_wd = ptimer_init_with_bh(t->bh_wd, PTIMER_POLICY_DEFAULT);
 
     sysbus_init_irq(sbd, &t->irq);
     sysbus_init_irq(sbd, &t->nmi);

hw/timer/exynos4210_mct.c

@@ -1429,7 +1429,7 @@ static void exynos4210_mct_init(Object *obj)
 
     /* Global timer */
     bh[0] = qemu_bh_new(exynos4210_gfrc_event, s);
-    s->g_timer.ptimer_frc = ptimer_init(bh[0], PTIMER_POLICY_DEFAULT);
+    s->g_timer.ptimer_frc = ptimer_init_with_bh(bh[0], PTIMER_POLICY_DEFAULT);
     memset(&s->g_timer.reg, 0, sizeof(struct gregs));
 
     /* Local timers */
@@ -1437,8 +1437,9 @@ static void exynos4210_mct_init(Object *obj)
         bh[0] = qemu_bh_new(exynos4210_ltick_event, &s->l_timer[i]);
         bh[1] = qemu_bh_new(exynos4210_lfrc_event, &s->l_timer[i]);
         s->l_timer[i].tick_timer.ptimer_tick =
-                                   ptimer_init(bh[0], PTIMER_POLICY_DEFAULT);
-        s->l_timer[i].ptimer_frc = ptimer_init(bh[1], PTIMER_POLICY_DEFAULT);
+            ptimer_init_with_bh(bh[0], PTIMER_POLICY_DEFAULT);
+        s->l_timer[i].ptimer_frc =
+            ptimer_init_with_bh(bh[1], PTIMER_POLICY_DEFAULT);
         s->l_timer[i].id = i;
     }
 

hw/timer/exynos4210_pwm.c

@@ -393,7 +393,7 @@ static void exynos4210_pwm_init(Object *obj)
     for (i = 0; i < EXYNOS4210_PWM_TIMERS_NUM; i++) {
         bh = qemu_bh_new(exynos4210_pwm_tick, &s->timer[i]);
         sysbus_init_irq(dev, &s->timer[i].irq);
-        s->timer[i].ptimer = ptimer_init(bh, PTIMER_POLICY_DEFAULT);
+        s->timer[i].ptimer = ptimer_init_with_bh(bh, PTIMER_POLICY_DEFAULT);
         s->timer[i].id = i;
         s->timer[i].parent = s;
     }

hw/timer/exynos4210_rtc.c

@@ -558,12 +558,12 @@ static void exynos4210_rtc_init(Object *obj)
     QEMUBH *bh;
 
     bh = qemu_bh_new(exynos4210_rtc_tick, s);
-    s->ptimer = ptimer_init(bh, PTIMER_POLICY_DEFAULT);
+    s->ptimer = ptimer_init_with_bh(bh, PTIMER_POLICY_DEFAULT);
     ptimer_set_freq(s->ptimer, RTC_BASE_FREQ);
     exynos4210_rtc_update_freq(s, 0);
 
     bh = qemu_bh_new(exynos4210_rtc_1Hz_tick, s);
-    s->ptimer_1Hz = ptimer_init(bh, PTIMER_POLICY_DEFAULT);
+    s->ptimer_1Hz = ptimer_init_with_bh(bh, PTIMER_POLICY_DEFAULT);
     ptimer_set_freq(s->ptimer_1Hz, RTC_BASE_FREQ);
 
     sysbus_init_irq(dev, &s->alm_irq);

hw/timer/grlib_gptimer.c

@@ -366,7 +366,7 @@ static void grlib_gptimer_realize(DeviceState *dev, Error **errp)
 
         timer->unit   = unit;
         timer->bh     = qemu_bh_new(grlib_gptimer_hit, timer);
-        timer->ptimer = ptimer_init(timer->bh, PTIMER_POLICY_DEFAULT);
+        timer->ptimer = ptimer_init_with_bh(timer->bh, PTIMER_POLICY_DEFAULT);
         timer->id     = i;
 
         /* One IRQ line for each timer */

hw/timer/imx_epit.c

@@ -317,10 +317,10 @@ static void imx_epit_realize(DeviceState *dev, Error **errp)
                           0x00001000);
     sysbus_init_mmio(sbd, &s->iomem);
 
-    s->timer_reload = ptimer_init(NULL, PTIMER_POLICY_DEFAULT);
+    s->timer_reload = ptimer_init_with_bh(NULL, PTIMER_POLICY_DEFAULT);
 
     bh = qemu_bh_new(imx_epit_cmp, s);
-    s->timer_cmp = ptimer_init(bh, PTIMER_POLICY_DEFAULT);
+    s->timer_cmp = ptimer_init_with_bh(bh, PTIMER_POLICY_DEFAULT);
 }
 
 static void imx_epit_class_init(ObjectClass *klass, void *data)