From 19d2b5e6ff7202c2bf45c547efa85ae6c2d76bbd Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Mon, 16 Feb 2015 14:08:22 +0100 Subject: i8257: rewrite DMA_schedule to avoid hooking into the CPU loop The i8257 DMA controller uses an idle bottom half, which by default does not cause the main loop to exit. Therefore, the DMA_schedule function is there to ensure that the CPU relinquishes the iothread mutex to the iothread. However, this is not enough since the iothread will call aio_compute_timeout() and go to sleep again. In the iothread world, forcing execution of the idle bottom half is much simpler, and only requires a call to qemu_notify_event(). Do it, removing the need for the "cpu_request_exit" pseudo-irq. The next patch will remove it. Reviewed-by: Richard Henderson Signed-off-by: Paolo Bonzini --- hw/dma/i8257.c | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-) (limited to 'hw/dma') diff --git a/hw/dma/i8257.c b/hw/dma/i8257.c index a414029bea..409ba7d01f 100644 --- a/hw/dma/i8257.c +++ b/hw/dma/i8257.c @@ -358,6 +358,7 @@ static void channel_run (int ncont, int ichan) } static QEMUBH *dma_bh; +static bool dma_bh_scheduled; static void DMA_run (void) { @@ -390,12 +391,15 @@ static void DMA_run (void) running = 0; out: - if (rearm) + if (rearm) { qemu_bh_schedule_idle(dma_bh); + dma_bh_scheduled = true; + } } static void DMA_run_bh(void *unused) { + dma_bh_scheduled = false; DMA_run(); } @@ -458,12 +462,14 @@ int DMA_write_memory (int nchan, void *buf, int pos, int len) return len; } -/* request the emulator to transfer a new DMA memory block ASAP */ -void DMA_schedule(int nchan) +/* request the emulator to transfer a new DMA memory block ASAP (even + * if the idle bottom half would not have exited the iothread yet). + */ +void DMA_schedule(void) { - struct dma_cont *d = &dma_controllers[nchan > 3]; - - qemu_irq_pulse(*d->cpu_request_exit); + if (dma_bh_scheduled) { + qemu_notify_event(); + } } static void dma_reset(void *opaque) -- cgit v1.2.3-55-g7522 From 5039d6e23586fe6bbedc5e4fe302b48a66890ade Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Mon, 16 Feb 2015 14:13:11 +0100 Subject: i8257: remove cpu_request_exit irq This is unused. cpu_exit now is almost exclusively an internal function to the CPU execution loop. In a few patches, we'll change the remaining occurrences to qemu_cpu_kick, making it truly internal. Reviewed-by: Richard henderson Signed-off-by: Paolo Bonzini --- hw/dma/i82374.c | 5 +---- hw/dma/i8257.c | 13 ++++--------- hw/i386/pc.c | 13 +------------ hw/isa/i82378.c | 3 +-- hw/mips/mips_fulong2e.c | 13 +------------ hw/mips/mips_jazz.c | 13 +------------ hw/mips/mips_malta.c | 13 +------------ hw/ppc/prep.c | 11 ----------- hw/sparc/sun4m.c | 2 +- hw/sparc64/sun4u.c | 2 +- include/hw/isa/isa.h | 2 +- 11 files changed, 13 insertions(+), 77 deletions(-) (limited to 'hw/dma') diff --git a/hw/dma/i82374.c b/hw/dma/i82374.c index b8ad2e64ec..f63097154f 100644 --- a/hw/dma/i82374.c +++ b/hw/dma/i82374.c @@ -38,7 +38,6 @@ do { fprintf(stderr, "i82374 ERROR: " fmt , ## __VA_ARGS__); } while (0) typedef struct I82374State { uint8_t commands[8]; - qemu_irq out; PortioList port_list; } I82374State; @@ -101,7 +100,7 @@ static uint32_t i82374_read_descriptor(void *opaque, uint32_t nport) static void i82374_realize(I82374State *s, Error **errp) { - DMA_init(1, &s->out); + DMA_init(1); memset(s->commands, 0, sizeof(s->commands)); } @@ -145,8 +144,6 @@ static void i82374_isa_realize(DeviceState *dev, Error **errp) isa->iobase); i82374_realize(s, errp); - - qdev_init_gpio_out(dev, &s->out, 1); } static Property i82374_properties[] = { diff --git a/hw/dma/i8257.c b/hw/dma/i8257.c index 409ba7d01f..13984244a6 100644 --- a/hw/dma/i8257.c +++ b/hw/dma/i8257.c @@ -59,7 +59,6 @@ static struct dma_cont { uint8_t flip_flop; int dshift; struct dma_regs regs[4]; - qemu_irq *cpu_request_exit; MemoryRegion channel_io; MemoryRegion cont_io; } dma_controllers[2]; @@ -521,13 +520,11 @@ static const MemoryRegionOps cont_io_ops = { /* dshift = 0: 8 bit DMA, 1 = 16 bit DMA */ static void dma_init2(struct dma_cont *d, int base, int dshift, - int page_base, int pageh_base, - qemu_irq *cpu_request_exit) + int page_base, int pageh_base) { int i; d->dshift = dshift; - d->cpu_request_exit = cpu_request_exit; memory_region_init_io(&d->channel_io, NULL, &channel_io_ops, d, "dma-chan", 8 << d->dshift); @@ -591,12 +588,10 @@ static const VMStateDescription vmstate_dma = { } }; -void DMA_init(int high_page_enable, qemu_irq *cpu_request_exit) +void DMA_init(int high_page_enable) { - dma_init2(&dma_controllers[0], 0x00, 0, 0x80, - high_page_enable ? 0x480 : -1, cpu_request_exit); - dma_init2(&dma_controllers[1], 0xc0, 1, 0x88, - high_page_enable ? 0x488 : -1, cpu_request_exit); + dma_init2(&dma_controllers[0], 0x00, 0, 0x80, high_page_enable ? 0x480 : -1); + dma_init2(&dma_controllers[1], 0xc0, 1, 0x88, high_page_enable ? 0x488 : -1); vmstate_register (NULL, 0, &vmstate_dma, &dma_controllers[0]); vmstate_register (NULL, 1, &vmstate_dma, &dma_controllers[1]); diff --git a/hw/i386/pc.c b/hw/i386/pc.c index 9f2924e5df..16d06c6bf8 100644 --- a/hw/i386/pc.c +++ b/hw/i386/pc.c @@ -1446,15 +1446,6 @@ DeviceState *pc_vga_init(ISABus *isa_bus, PCIBus *pci_bus) return dev; } -static void cpu_request_exit(void *opaque, int irq, int level) -{ - CPUState *cpu = current_cpu; - - if (cpu && level) { - cpu_exit(cpu); - } -} - static const MemoryRegionOps ioport80_io_ops = { .write = ioport80_write, .read = ioport80_read, @@ -1489,7 +1480,6 @@ void pc_basic_device_init(ISABus *isa_bus, qemu_irq *gsi, qemu_irq rtc_irq = NULL; qemu_irq *a20_line; ISADevice *i8042, *port92, *vmmouse, *pit = NULL; - qemu_irq *cpu_exit_irq; MemoryRegion *ioport80_io = g_new(MemoryRegion, 1); MemoryRegion *ioportF0_io = g_new(MemoryRegion, 1); @@ -1566,8 +1556,7 @@ void pc_basic_device_init(ISABus *isa_bus, qemu_irq *gsi, port92 = isa_create_simple(isa_bus, "port92"); port92_init(port92, &a20_line[1]); - cpu_exit_irq = qemu_allocate_irqs(cpu_request_exit, NULL, 1); - DMA_init(0, cpu_exit_irq); + DMA_init(0); for(i = 0; i < MAX_FD; i++) { fd[i] = drive_get(IF_FLOPPY, 0, i); diff --git a/hw/isa/i82378.c b/hw/isa/i82378.c index fcf97d86ac..d4c830684b 100644 --- a/hw/isa/i82378.c +++ b/hw/isa/i82378.c @@ -100,7 +100,6 @@ static void i82378_realize(PCIDevice *pci, Error **errp) /* 2 82C37 (dma) */ isa = isa_create_simple(isabus, "i82374"); - qdev_connect_gpio_out(DEVICE(isa), 0, s->out[1]); /* timer */ isa_create_simple(isabus, "mc146818rtc"); @@ -111,7 +110,7 @@ static void i82378_init(Object *obj) DeviceState *dev = DEVICE(obj); I82378State *s = I82378(obj); - qdev_init_gpio_out(dev, s->out, 2); + qdev_init_gpio_out(dev, s->out, 1); qdev_init_gpio_in(dev, i82378_request_pic_irq, 16); } diff --git a/hw/mips/mips_fulong2e.c b/hw/mips/mips_fulong2e.c index dea941ad88..6d2ea30bb0 100644 --- a/hw/mips/mips_fulong2e.c +++ b/hw/mips/mips_fulong2e.c @@ -251,15 +251,6 @@ static void network_init (PCIBus *pci_bus) } } -static void cpu_request_exit(void *opaque, int irq, int level) -{ - CPUState *cpu = current_cpu; - - if (cpu && level) { - cpu_exit(cpu); - } -} - static void mips_fulong2e_init(MachineState *machine) { ram_addr_t ram_size = machine->ram_size; @@ -274,7 +265,6 @@ static void mips_fulong2e_init(MachineState *machine) long bios_size; int64_t kernel_entry; qemu_irq *i8259; - qemu_irq *cpu_exit_irq; PCIBus *pci_bus; ISABus *isa_bus; I2CBus *smbus; @@ -375,8 +365,7 @@ static void mips_fulong2e_init(MachineState *machine) /* init other devices */ pit = pit_init(isa_bus, 0x40, 0, NULL); - cpu_exit_irq = qemu_allocate_irqs(cpu_request_exit, NULL, 1); - DMA_init(0, cpu_exit_irq); + DMA_init(0); /* Super I/O */ isa_create_simple(isa_bus, "i8042"); diff --git a/hw/mips/mips_jazz.c b/hw/mips/mips_jazz.c index 9d60633efb..3906016ac4 100644 --- a/hw/mips/mips_jazz.c +++ b/hw/mips/mips_jazz.c @@ -104,15 +104,6 @@ static const MemoryRegionOps dma_dummy_ops = { #define MAGNUM_BIOS_SIZE_MAX 0x7e000 #define MAGNUM_BIOS_SIZE (BIOS_SIZE < MAGNUM_BIOS_SIZE_MAX ? BIOS_SIZE : MAGNUM_BIOS_SIZE_MAX) -static void cpu_request_exit(void *opaque, int irq, int level) -{ - CPUState *cpu = current_cpu; - - if (cpu && level) { - cpu_exit(cpu); - } -} - static CPUUnassignedAccess real_do_unassigned_access; static void mips_jazz_do_unassigned_access(CPUState *cpu, hwaddr addr, bool is_write, bool is_exec, @@ -150,7 +141,6 @@ static void mips_jazz_init(MachineState *machine, ISADevice *pit; DriveInfo *fds[MAX_FD]; qemu_irq esp_reset, dma_enable; - qemu_irq *cpu_exit_irq; MemoryRegion *ram = g_new(MemoryRegion, 1); MemoryRegion *bios = g_new(MemoryRegion, 1); MemoryRegion *bios2 = g_new(MemoryRegion, 1); @@ -234,8 +224,7 @@ static void mips_jazz_init(MachineState *machine, /* ISA devices */ i8259 = i8259_init(isa_bus, env->irq[4]); isa_bus_irqs(isa_bus, i8259); - cpu_exit_irq = qemu_allocate_irqs(cpu_request_exit, NULL, 1); - DMA_init(0, cpu_exit_irq); + DMA_init(0); pit = pit_init(isa_bus, 0x40, 0, NULL); pcspk_init(isa_bus, pit); diff --git a/hw/mips/mips_malta.c b/hw/mips/mips_malta.c index 3082e75340..23b6fc36a5 100644 --- a/hw/mips/mips_malta.c +++ b/hw/mips/mips_malta.c @@ -905,15 +905,6 @@ static void main_cpu_reset(void *opaque) } } -static void cpu_request_exit(void *opaque, int irq, int level) -{ - CPUState *cpu = current_cpu; - - if (cpu && level) { - cpu_exit(cpu); - } -} - static void mips_malta_init(MachineState *machine) { @@ -939,7 +930,6 @@ void mips_malta_init(MachineState *machine) MIPSCPU *cpu; CPUMIPSState *env; qemu_irq *isa_irq; - qemu_irq *cpu_exit_irq; int piix4_devfn; I2CBus *smbus; int i; @@ -1175,8 +1165,7 @@ void mips_malta_init(MachineState *machine) smbus_eeprom_init(smbus, 8, smbus_eeprom_buf, smbus_eeprom_size); g_free(smbus_eeprom_buf); pit = pit_init(isa_bus, 0x40, 0, NULL); - cpu_exit_irq = qemu_allocate_irqs(cpu_request_exit, NULL, 1); - DMA_init(0, cpu_exit_irq); + DMA_init(0); /* Super I/O */ isa_create_simple(isa_bus, "i8042"); diff --git a/hw/ppc/prep.c b/hw/ppc/prep.c index 45b5f62d6e..81f0838cd9 100644 --- a/hw/ppc/prep.c +++ b/hw/ppc/prep.c @@ -336,15 +336,6 @@ static uint32_t PREP_io_800_readb (void *opaque, uint32_t addr) #define NVRAM_SIZE 0x2000 -static void cpu_request_exit(void *opaque, int irq, int level) -{ - CPUState *cpu = current_cpu; - - if (cpu && level) { - cpu_exit(cpu); - } -} - static void ppc_prep_reset(void *opaque) { PowerPCCPU *cpu = opaque; @@ -626,8 +617,6 @@ static void ppc_prep_init(MachineState *machine) cpu = POWERPC_CPU(first_cpu); qdev_connect_gpio_out(&pci->qdev, 0, cpu->env.irq_inputs[PPC6xx_INPUT_INT]); - qdev_connect_gpio_out(&pci->qdev, 1, - qemu_allocate_irq(cpu_request_exit, NULL, 0)); sysbus_connect_irq(&pcihost->busdev, 0, qdev_get_gpio_in(&pci->qdev, 9)); sysbus_connect_irq(&pcihost->busdev, 1, qdev_get_gpio_in(&pci->qdev, 11)); sysbus_connect_irq(&pcihost->busdev, 2, qdev_get_gpio_in(&pci->qdev, 9)); diff --git a/hw/sparc/sun4m.c b/hw/sparc/sun4m.c index ebaae9df27..b5db8b7a00 100644 --- a/hw/sparc/sun4m.c +++ b/hw/sparc/sun4m.c @@ -111,7 +111,7 @@ void DMA_hold_DREQ (int nchan) {} void DMA_release_DREQ (int nchan) {} void DMA_schedule(void) {} -void DMA_init(int high_page_enable, qemu_irq *cpu_request_exit) +void DMA_init(int high_page_enable) { } diff --git a/hw/sparc64/sun4u.c b/hw/sparc64/sun4u.c index 44eb4ebb79..a887a86b7d 100644 --- a/hw/sparc64/sun4u.c +++ b/hw/sparc64/sun4u.c @@ -114,7 +114,7 @@ void DMA_hold_DREQ (int nchan) {} void DMA_release_DREQ (int nchan) {} void DMA_schedule(void) {} -void DMA_init(int high_page_enable, qemu_irq *cpu_request_exit) +void DMA_init(int high_page_enable) { } diff --git a/include/hw/isa/isa.h b/include/hw/isa/isa.h index 81b94ea264..d758b39a2e 100644 --- a/include/hw/isa/isa.h +++ b/include/hw/isa/isa.h @@ -113,7 +113,7 @@ int DMA_write_memory (int nchan, void *buf, int pos, int size); void DMA_hold_DREQ (int nchan); void DMA_release_DREQ (int nchan); void DMA_schedule(void); -void DMA_init(int high_page_enable, qemu_irq *cpu_request_exit); +void DMA_init(int high_page_enable); void DMA_register_channel (int nchan, DMA_transfer_handler transfer_handler, void *opaque); -- cgit v1.2.3-55-g7522