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authorRajithaY <rajithax.yerrumsetty@intel.com>2017-04-25 03:31:15 -0700
committerRajitha Yerrumchetty <rajithax.yerrumsetty@intel.com>2017-05-22 06:48:08 +0000
commitbb756eebdac6fd24e8919e2c43f7d2c8c4091f59 (patch)
treeca11e03542edf2d8f631efeca5e1626d211107e3 /qemu/aio-posix.c
parenta14b48d18a9ed03ec191cf16b162206998a895ce (diff)
Adding qemu as a submodule of KVMFORNFV
This Patch includes the changes to add qemu as a submodule to kvmfornfv repo and make use of the updated latest qemu for the execution of all testcase Change-Id: I1280af507a857675c7f81d30c95255635667bdd7 Signed-off-by:RajithaY<rajithax.yerrumsetty@intel.com>
Diffstat (limited to 'qemu/aio-posix.c')
-rw-r--r--qemu/aio-posix.c499
1 files changed, 0 insertions, 499 deletions
diff --git a/qemu/aio-posix.c b/qemu/aio-posix.c
deleted file mode 100644
index 6006122e0..000000000
--- a/qemu/aio-posix.c
+++ /dev/null
@@ -1,499 +0,0 @@
-/*
- * QEMU aio implementation
- *
- * Copyright IBM, Corp. 2008
- *
- * Authors:
- * Anthony Liguori <aliguori@us.ibm.com>
- *
- * This work is licensed under the terms of the GNU GPL, version 2. See
- * the COPYING file in the top-level directory.
- *
- * Contributions after 2012-01-13 are licensed under the terms of the
- * GNU GPL, version 2 or (at your option) any later version.
- */
-
-#include "qemu/osdep.h"
-#include "qemu-common.h"
-#include "block/block.h"
-#include "qemu/queue.h"
-#include "qemu/sockets.h"
-#ifdef CONFIG_EPOLL_CREATE1
-#include <sys/epoll.h>
-#endif
-
-struct AioHandler
-{
- GPollFD pfd;
- IOHandler *io_read;
- IOHandler *io_write;
- int deleted;
- void *opaque;
- bool is_external;
- QLIST_ENTRY(AioHandler) node;
-};
-
-#ifdef CONFIG_EPOLL_CREATE1
-
-/* The fd number threashold to switch to epoll */
-#define EPOLL_ENABLE_THRESHOLD 64
-
-static void aio_epoll_disable(AioContext *ctx)
-{
- ctx->epoll_available = false;
- if (!ctx->epoll_enabled) {
- return;
- }
- ctx->epoll_enabled = false;
- close(ctx->epollfd);
-}
-
-static inline int epoll_events_from_pfd(int pfd_events)
-{
- return (pfd_events & G_IO_IN ? EPOLLIN : 0) |
- (pfd_events & G_IO_OUT ? EPOLLOUT : 0) |
- (pfd_events & G_IO_HUP ? EPOLLHUP : 0) |
- (pfd_events & G_IO_ERR ? EPOLLERR : 0);
-}
-
-static bool aio_epoll_try_enable(AioContext *ctx)
-{
- AioHandler *node;
- struct epoll_event event;
-
- QLIST_FOREACH(node, &ctx->aio_handlers, node) {
- int r;
- if (node->deleted || !node->pfd.events) {
- continue;
- }
- event.events = epoll_events_from_pfd(node->pfd.events);
- event.data.ptr = node;
- r = epoll_ctl(ctx->epollfd, EPOLL_CTL_ADD, node->pfd.fd, &event);
- if (r) {
- return false;
- }
- }
- ctx->epoll_enabled = true;
- return true;
-}
-
-static void aio_epoll_update(AioContext *ctx, AioHandler *node, bool is_new)
-{
- struct epoll_event event;
- int r;
-
- if (!ctx->epoll_enabled) {
- return;
- }
- if (!node->pfd.events) {
- r = epoll_ctl(ctx->epollfd, EPOLL_CTL_DEL, node->pfd.fd, &event);
- if (r) {
- aio_epoll_disable(ctx);
- }
- } else {
- event.data.ptr = node;
- event.events = epoll_events_from_pfd(node->pfd.events);
- if (is_new) {
- r = epoll_ctl(ctx->epollfd, EPOLL_CTL_ADD, node->pfd.fd, &event);
- if (r) {
- aio_epoll_disable(ctx);
- }
- } else {
- r = epoll_ctl(ctx->epollfd, EPOLL_CTL_MOD, node->pfd.fd, &event);
- if (r) {
- aio_epoll_disable(ctx);
- }
- }
- }
-}
-
-static int aio_epoll(AioContext *ctx, GPollFD *pfds,
- unsigned npfd, int64_t timeout)
-{
- AioHandler *node;
- int i, ret = 0;
- struct epoll_event events[128];
-
- assert(npfd == 1);
- assert(pfds[0].fd == ctx->epollfd);
- if (timeout > 0) {
- ret = qemu_poll_ns(pfds, npfd, timeout);
- }
- if (timeout <= 0 || ret > 0) {
- ret = epoll_wait(ctx->epollfd, events,
- sizeof(events) / sizeof(events[0]),
- timeout);
- if (ret <= 0) {
- goto out;
- }
- for (i = 0; i < ret; i++) {
- int ev = events[i].events;
- node = events[i].data.ptr;
- node->pfd.revents = (ev & EPOLLIN ? G_IO_IN : 0) |
- (ev & EPOLLOUT ? G_IO_OUT : 0) |
- (ev & EPOLLHUP ? G_IO_HUP : 0) |
- (ev & EPOLLERR ? G_IO_ERR : 0);
- }
- }
-out:
- return ret;
-}
-
-static bool aio_epoll_enabled(AioContext *ctx)
-{
- /* Fall back to ppoll when external clients are disabled. */
- return !aio_external_disabled(ctx) && ctx->epoll_enabled;
-}
-
-static bool aio_epoll_check_poll(AioContext *ctx, GPollFD *pfds,
- unsigned npfd, int64_t timeout)
-{
- if (!ctx->epoll_available) {
- return false;
- }
- if (aio_epoll_enabled(ctx)) {
- return true;
- }
- if (npfd >= EPOLL_ENABLE_THRESHOLD) {
- if (aio_epoll_try_enable(ctx)) {
- return true;
- } else {
- aio_epoll_disable(ctx);
- }
- }
- return false;
-}
-
-#else
-
-static void aio_epoll_update(AioContext *ctx, AioHandler *node, bool is_new)
-{
-}
-
-static int aio_epoll(AioContext *ctx, GPollFD *pfds,
- unsigned npfd, int64_t timeout)
-{
- assert(false);
-}
-
-static bool aio_epoll_enabled(AioContext *ctx)
-{
- return false;
-}
-
-static bool aio_epoll_check_poll(AioContext *ctx, GPollFD *pfds,
- unsigned npfd, int64_t timeout)
-{
- return false;
-}
-
-#endif
-
-static AioHandler *find_aio_handler(AioContext *ctx, int fd)
-{
- AioHandler *node;
-
- QLIST_FOREACH(node, &ctx->aio_handlers, node) {
- if (node->pfd.fd == fd)
- if (!node->deleted)
- return node;
- }
-
- return NULL;
-}
-
-void aio_set_fd_handler(AioContext *ctx,
- int fd,
- bool is_external,
- IOHandler *io_read,
- IOHandler *io_write,
- void *opaque)
-{
- AioHandler *node;
- bool is_new = false;
- bool deleted = false;
-
- node = find_aio_handler(ctx, fd);
-
- /* Are we deleting the fd handler? */
- if (!io_read && !io_write) {
- if (node) {
- g_source_remove_poll(&ctx->source, &node->pfd);
-
- /* If the lock is held, just mark the node as deleted */
- if (ctx->walking_handlers) {
- node->deleted = 1;
- node->pfd.revents = 0;
- } else {
- /* Otherwise, delete it for real. We can't just mark it as
- * deleted because deleted nodes are only cleaned up after
- * releasing the walking_handlers lock.
- */
- QLIST_REMOVE(node, node);
- deleted = true;
- }
- }
- } else {
- if (node == NULL) {
- /* Alloc and insert if it's not already there */
- node = g_new0(AioHandler, 1);
- node->pfd.fd = fd;
- QLIST_INSERT_HEAD(&ctx->aio_handlers, node, node);
-
- g_source_add_poll(&ctx->source, &node->pfd);
- is_new = true;
- }
- /* Update handler with latest information */
- node->io_read = io_read;
- node->io_write = io_write;
- node->opaque = opaque;
- node->is_external = is_external;
-
- node->pfd.events = (io_read ? G_IO_IN | G_IO_HUP | G_IO_ERR : 0);
- node->pfd.events |= (io_write ? G_IO_OUT | G_IO_ERR : 0);
- }
-
- aio_epoll_update(ctx, node, is_new);
- aio_notify(ctx);
- if (deleted) {
- g_free(node);
- }
-}
-
-void aio_set_event_notifier(AioContext *ctx,
- EventNotifier *notifier,
- bool is_external,
- EventNotifierHandler *io_read)
-{
- aio_set_fd_handler(ctx, event_notifier_get_fd(notifier),
- is_external, (IOHandler *)io_read, NULL, notifier);
-}
-
-bool aio_prepare(AioContext *ctx)
-{
- return false;
-}
-
-bool aio_pending(AioContext *ctx)
-{
- AioHandler *node;
-
- QLIST_FOREACH(node, &ctx->aio_handlers, node) {
- int revents;
-
- revents = node->pfd.revents & node->pfd.events;
- if (revents & (G_IO_IN | G_IO_HUP | G_IO_ERR) && node->io_read &&
- aio_node_check(ctx, node->is_external)) {
- return true;
- }
- if (revents & (G_IO_OUT | G_IO_ERR) && node->io_write &&
- aio_node_check(ctx, node->is_external)) {
- return true;
- }
- }
-
- return false;
-}
-
-bool aio_dispatch(AioContext *ctx)
-{
- AioHandler *node;
- bool progress = false;
-
- /*
- * If there are callbacks left that have been queued, we need to call them.
- * Do not call select in this case, because it is possible that the caller
- * does not need a complete flush (as is the case for aio_poll loops).
- */
- if (aio_bh_poll(ctx)) {
- progress = true;
- }
-
- /*
- * We have to walk very carefully in case aio_set_fd_handler is
- * called while we're walking.
- */
- node = QLIST_FIRST(&ctx->aio_handlers);
- while (node) {
- AioHandler *tmp;
- int revents;
-
- ctx->walking_handlers++;
-
- revents = node->pfd.revents & node->pfd.events;
- node->pfd.revents = 0;
-
- if (!node->deleted &&
- (revents & (G_IO_IN | G_IO_HUP | G_IO_ERR)) &&
- aio_node_check(ctx, node->is_external) &&
- node->io_read) {
- node->io_read(node->opaque);
-
- /* aio_notify() does not count as progress */
- if (node->opaque != &ctx->notifier) {
- progress = true;
- }
- }
- if (!node->deleted &&
- (revents & (G_IO_OUT | G_IO_ERR)) &&
- aio_node_check(ctx, node->is_external) &&
- node->io_write) {
- node->io_write(node->opaque);
- progress = true;
- }
-
- tmp = node;
- node = QLIST_NEXT(node, node);
-
- ctx->walking_handlers--;
-
- if (!ctx->walking_handlers && tmp->deleted) {
- QLIST_REMOVE(tmp, node);
- g_free(tmp);
- }
- }
-
- /* Run our timers */
- progress |= timerlistgroup_run_timers(&ctx->tlg);
-
- return progress;
-}
-
-/* These thread-local variables are used only in a small part of aio_poll
- * around the call to the poll() system call. In particular they are not
- * used while aio_poll is performing callbacks, which makes it much easier
- * to think about reentrancy!
- *
- * Stack-allocated arrays would be perfect but they have size limitations;
- * heap allocation is expensive enough that we want to reuse arrays across
- * calls to aio_poll(). And because poll() has to be called without holding
- * any lock, the arrays cannot be stored in AioContext. Thread-local data
- * has none of the disadvantages of these three options.
- */
-static __thread GPollFD *pollfds;
-static __thread AioHandler **nodes;
-static __thread unsigned npfd, nalloc;
-static __thread Notifier pollfds_cleanup_notifier;
-
-static void pollfds_cleanup(Notifier *n, void *unused)
-{
- g_assert(npfd == 0);
- g_free(pollfds);
- g_free(nodes);
- nalloc = 0;
-}
-
-static void add_pollfd(AioHandler *node)
-{
- if (npfd == nalloc) {
- if (nalloc == 0) {
- pollfds_cleanup_notifier.notify = pollfds_cleanup;
- qemu_thread_atexit_add(&pollfds_cleanup_notifier);
- nalloc = 8;
- } else {
- g_assert(nalloc <= INT_MAX);
- nalloc *= 2;
- }
- pollfds = g_renew(GPollFD, pollfds, nalloc);
- nodes = g_renew(AioHandler *, nodes, nalloc);
- }
- nodes[npfd] = node;
- pollfds[npfd] = (GPollFD) {
- .fd = node->pfd.fd,
- .events = node->pfd.events,
- };
- npfd++;
-}
-
-bool aio_poll(AioContext *ctx, bool blocking)
-{
- AioHandler *node;
- int i, ret;
- bool progress;
- int64_t timeout;
-
- aio_context_acquire(ctx);
- progress = false;
-
- /* aio_notify can avoid the expensive event_notifier_set if
- * everything (file descriptors, bottom halves, timers) will
- * be re-evaluated before the next blocking poll(). This is
- * already true when aio_poll is called with blocking == false;
- * if blocking == true, it is only true after poll() returns,
- * so disable the optimization now.
- */
- if (blocking) {
- atomic_add(&ctx->notify_me, 2);
- }
-
- ctx->walking_handlers++;
-
- assert(npfd == 0);
-
- /* fill pollfds */
- QLIST_FOREACH(node, &ctx->aio_handlers, node) {
- if (!node->deleted && node->pfd.events
- && !aio_epoll_enabled(ctx)
- && aio_node_check(ctx, node->is_external)) {
- add_pollfd(node);
- }
- }
-
- timeout = blocking ? aio_compute_timeout(ctx) : 0;
-
- /* wait until next event */
- if (timeout) {
- aio_context_release(ctx);
- }
- if (aio_epoll_check_poll(ctx, pollfds, npfd, timeout)) {
- AioHandler epoll_handler;
-
- epoll_handler.pfd.fd = ctx->epollfd;
- epoll_handler.pfd.events = G_IO_IN | G_IO_OUT | G_IO_HUP | G_IO_ERR;
- npfd = 0;
- add_pollfd(&epoll_handler);
- ret = aio_epoll(ctx, pollfds, npfd, timeout);
- } else {
- ret = qemu_poll_ns(pollfds, npfd, timeout);
- }
- if (blocking) {
- atomic_sub(&ctx->notify_me, 2);
- }
- if (timeout) {
- aio_context_acquire(ctx);
- }
-
- aio_notify_accept(ctx);
-
- /* if we have any readable fds, dispatch event */
- if (ret > 0) {
- for (i = 0; i < npfd; i++) {
- nodes[i]->pfd.revents = pollfds[i].revents;
- }
- }
-
- npfd = 0;
- ctx->walking_handlers--;
-
- /* Run dispatch even if there were no readable fds to run timers */
- if (aio_dispatch(ctx)) {
- progress = true;
- }
-
- aio_context_release(ctx);
-
- return progress;
-}
-
-void aio_context_setup(AioContext *ctx, Error **errp)
-{
-#ifdef CONFIG_EPOLL_CREATE1
- assert(!ctx->epollfd);
- ctx->epollfd = epoll_create1(EPOLL_CLOEXEC);
- if (ctx->epollfd == -1) {
- ctx->epoll_available = false;
- } else {
- ctx->epoll_available = true;
- }
-#endif
-}