* [patch 1/2] qemu-kvm: use usptream eventfd code
2010-09-06 20:20 [patch 0/2] qemu-kvm cleanups Marcelo Tosatti
@ 2010-09-06 20:20 ` Marcelo Tosatti
2010-09-07 8:21 ` Avi Kivity
2010-09-06 20:20 ` [patch 2/2] qemu-kvm: drop posix-aio-compat.cs signalfd usage Marcelo Tosatti
1 sibling, 1 reply; 6+ messages in thread
From: Marcelo Tosatti @ 2010-09-06 20:20 UTC (permalink / raw)
To: kvm; +Cc: avi, Anthony Liguori, Marcelo Tosatti
[-- Attachment #1: qemu-notify-event --]
[-- Type: text/plain, Size: 3123 bytes --]
Upstream code is equivalent.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Index: qemu-kvm/cpus.c
===================================================================
--- qemu-kvm.orig/cpus.c
+++ qemu-kvm/cpus.c
@@ -290,11 +290,6 @@ void qemu_notify_event(void)
{
CPUState *env = cpu_single_env;
- if (kvm_enabled()) {
- qemu_kvm_notify_work();
- return;
- }
-
qemu_event_increment ();
if (env) {
cpu_exit(env);
Index: qemu-kvm/qemu-kvm.c
===================================================================
--- qemu-kvm.orig/qemu-kvm.c
+++ qemu-kvm/qemu-kvm.c
@@ -71,7 +71,6 @@ static int qemu_system_ready;
#define SIG_IPI (SIGRTMIN+4)
pthread_t io_thread;
-static int io_thread_fd = -1;
static int io_thread_sigfd = -1;
static CPUState *kvm_debug_cpu_requested;
@@ -1634,28 +1633,6 @@ int kvm_init_ap(void)
return 0;
}
-void qemu_kvm_notify_work(void)
-{
- /* Write 8 bytes to be compatible with eventfd. */
- static uint64_t val = 1;
- ssize_t ret;
-
- if (io_thread_fd == -1) {
- return;
- }
-
- do {
- ret = write(io_thread_fd, &val, sizeof(val));
- } while (ret < 0 && errno == EINTR);
-
- /* EAGAIN is fine in case we have a pipe. */
- if (ret < 0 && errno != EAGAIN) {
- fprintf(stderr, "qemu_kvm_notify_work: write() filed: %s\n",
- strerror(errno));
- exit (1);
- }
-}
-
/* If we have signalfd, we mask out the signals we want to handle and then
* use signalfd to listen for them. We rely on whatever the current signal
* handler is to dispatch the signals when we receive them.
@@ -1692,41 +1669,14 @@ static void sigfd_handler(void *opaque)
}
}
-/* Used to break IO thread out of select */
-static void io_thread_wakeup(void *opaque)
-{
- int fd = (unsigned long) opaque;
- ssize_t len;
- char buffer[512];
-
- /* Drain the notify pipe. For eventfd, only 8 bytes will be read. */
- do {
- len = read(fd, buffer, sizeof(buffer));
- } while ((len == -1 && errno == EINTR) || len == sizeof(buffer));
-}
-
int kvm_main_loop(void)
{
- int fds[2];
sigset_t mask;
int sigfd;
io_thread = pthread_self();
qemu_system_ready = 1;
- if (qemu_eventfd(fds) == -1) {
- fprintf(stderr, "failed to create eventfd\n");
- return -errno;
- }
-
- fcntl(fds[0], F_SETFL, O_NONBLOCK);
- fcntl(fds[1], F_SETFL, O_NONBLOCK);
-
- qemu_set_fd_handler2(fds[0], NULL, io_thread_wakeup, NULL,
- (void *)(unsigned long) fds[0]);
-
- io_thread_fd = fds[1];
-
sigemptyset(&mask);
sigaddset(&mask, SIGIO);
sigaddset(&mask, SIGALRM);
Index: qemu-kvm/qemu-kvm.h
===================================================================
--- qemu-kvm.orig/qemu-kvm.h
+++ qemu-kvm/qemu-kvm.h
@@ -863,8 +863,6 @@ void qemu_kvm_aio_wait_start(void);
void qemu_kvm_aio_wait(void);
void qemu_kvm_aio_wait_end(void);
-void qemu_kvm_notify_work(void);
-
void kvm_tpr_access_report(CPUState *env, uint64_t rip, int is_write);
int kvm_arch_init_irq_routing(void);
^ permalink raw reply [flat|nested] 6+ messages in thread* [patch 2/2] qemu-kvm: drop posix-aio-compat.cs signalfd usage
2010-09-06 20:20 [patch 0/2] qemu-kvm cleanups Marcelo Tosatti
2010-09-06 20:20 ` [patch 1/2] qemu-kvm: use usptream eventfd code Marcelo Tosatti
@ 2010-09-06 20:20 ` Marcelo Tosatti
1 sibling, 0 replies; 6+ messages in thread
From: Marcelo Tosatti @ 2010-09-06 20:20 UTC (permalink / raw)
To: kvm; +Cc: avi, Anthony Liguori, Marcelo Tosatti
[-- Attachment #1: posix-aio-compat-use-signal --]
[-- Type: text/plain, Size: 3996 bytes --]
Block SIGUSR2, which makes the signal be handled through qemu-kvm.c's
signalfd.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Index: qemu-kvm/posix-aio-compat.c
===================================================================
--- qemu-kvm.orig/posix-aio-compat.c
+++ qemu-kvm/posix-aio-compat.c
@@ -26,7 +26,6 @@
#include "osdep.h"
#include "qemu-common.h"
#include "block_int.h"
-#include "compatfd.h"
#include "block/raw-posix-aio.h"
@@ -54,7 +53,7 @@ struct qemu_paiocb {
};
typedef struct PosixAioState {
- int fd;
+ int rfd, wfd;
struct qemu_paiocb *first_aio;
} PosixAioState;
@@ -473,29 +472,18 @@ static int posix_aio_process_queue(void
static void posix_aio_read(void *opaque)
{
PosixAioState *s = opaque;
- union {
- struct qemu_signalfd_siginfo siginfo;
- char buf[128];
- } sig;
- size_t offset;
-
- /* try to read from signalfd, don't freak out if we can't read anything */
- offset = 0;
- while (offset < 128) {
- ssize_t len;
+ ssize_t len;
- len = read(s->fd, sig.buf + offset, 128 - offset);
- if (len == -1 && errno == EINTR)
- continue;
- if (len == -1 && errno == EAGAIN) {
- /* there is no natural reason for this to happen,
- * so we'll spin hard until we get everything just
- * to be on the safe side. */
- if (offset > 0)
- continue;
- }
+ /* read all bytes from signal pipe */
+ for (;;) {
+ char bytes[16];
- offset += len;
+ len = read(s->rfd, bytes, sizeof(bytes));
+ if (len == -1 && errno == EINTR)
+ continue; /* try again */
+ if (len == sizeof(bytes))
+ continue; /* more to read */
+ break;
}
posix_aio_process_queue(s);
@@ -509,6 +497,20 @@ static int posix_aio_flush(void *opaque)
static PosixAioState *posix_aio_state;
+static void aio_signal_handler(int signum)
+{
+ if (posix_aio_state) {
+ char byte = 0;
+ ssize_t ret;
+
+ ret = write(posix_aio_state->wfd, &byte, sizeof(byte));
+ if (ret < 0 && errno != EAGAIN)
+ die("write()");
+ }
+
+ qemu_service_io();
+}
+
static void paio_remove(struct qemu_paiocb *acb)
{
struct qemu_paiocb **pacb;
@@ -610,8 +612,9 @@ BlockDriverAIOCB *paio_ioctl(BlockDriver
int paio_init(void)
{
- sigset_t mask;
+ struct sigaction act;
PosixAioState *s;
+ int fds[2];
int ret;
if (posix_aio_state)
@@ -619,21 +622,24 @@ int paio_init(void)
s = qemu_malloc(sizeof(PosixAioState));
- /* Make sure to block AIO signal */
- sigemptyset(&mask);
- sigaddset(&mask, SIGUSR2);
- sigprocmask(SIG_BLOCK, &mask, NULL);
+ sigfillset(&act.sa_mask);
+ act.sa_flags = 0; /* do not restart syscalls to interrupt select() */
+ act.sa_handler = aio_signal_handler;
+ sigaction(SIGUSR2, &act, NULL);
s->first_aio = NULL;
- s->fd = qemu_signalfd(&mask);
- if (s->fd == -1) {
- fprintf(stderr, "failed to create signalfd\n");
+ if (qemu_pipe(fds) == -1) {
+ fprintf(stderr, "failed to create pipe\n");
return -1;
}
- fcntl(s->fd, F_SETFL, O_NONBLOCK);
+ s->rfd = fds[0];
+ s->wfd = fds[1];
+
+ fcntl(s->rfd, F_SETFL, O_NONBLOCK);
+ fcntl(s->wfd, F_SETFL, O_NONBLOCK);
- qemu_aio_set_fd_handler(s->fd, posix_aio_read, NULL, posix_aio_flush,
+ qemu_aio_set_fd_handler(s->rfd, posix_aio_read, NULL, posix_aio_flush,
posix_aio_process_queue, s);
ret = pthread_attr_init(&attr);
Index: qemu-kvm/qemu-kvm.c
===================================================================
--- qemu-kvm.orig/qemu-kvm.c
+++ qemu-kvm/qemu-kvm.c
@@ -1680,6 +1680,7 @@ int kvm_main_loop(void)
sigemptyset(&mask);
sigaddset(&mask, SIGIO);
sigaddset(&mask, SIGALRM);
+ sigaddset(&mask, SIGUSR2);
sigaddset(&mask, SIGBUS);
sigprocmask(SIG_BLOCK, &mask, NULL);
^ permalink raw reply [flat|nested] 6+ messages in thread