From: Liu Ping Fan <pingf...@linux.vnet.ibm.com> Bind each NetClientState with a GSource(ie,NetClientSource). Currently, these GSource attached with default context, but in future, after resolving the race between handlers and the interface exposed by NetClientInfo and other re-entrant issue, we can run NetClientState on different threads
Signed-off-by: Liu Ping Fan <pingf...@linux.vnet.ibm.com> --- include/net/net.h | 27 +++++++++++++++ net/net.c | 96 +++++++++++++++++++++++++++++++++++++++++++++++++++++ net/tap.c | 57 +++++++++++++++++++++++++------ 3 files changed, 169 insertions(+), 11 deletions(-) diff --git a/include/net/net.h b/include/net/net.h index cb049a1..8fdb7eb 100644 --- a/include/net/net.h +++ b/include/net/net.h @@ -44,6 +44,7 @@ typedef ssize_t (NetReceiveIOV)(NetClientState *, const struct iovec *, int); typedef void (NetCleanup) (NetClientState *); typedef void (LinkStatusChanged)(NetClientState *); typedef void (NetClientDestructor)(NetClientState *); +typedef void (NetClientBindCtx)(NetClientState *, GMainContext *); typedef struct NetClientInfo { NetClientOptionsKind type; @@ -55,8 +56,25 @@ typedef struct NetClientInfo { NetCleanup *cleanup; LinkStatusChanged *link_status_changed; NetPoll *poll; + NetClientBindCtx *bind_ctx; } NetClientInfo; +typedef bool (*Pollable)(void *opaque); + +typedef struct NetClientSource { + GSource source; + GPollFD gfd; + GMainContext *ctx; + + Pollable readable; + Pollable writeable; + /* status returned by pollable last time */ + bool last_rd_sts; + bool last_wr_sts; + + void *opaque; +} NetClientSource; + struct NetClientState { NetClientInfo *info; int link_down; @@ -69,6 +87,10 @@ struct NetClientState { unsigned receive_disabled : 1; NetClientDestructor *destructor; unsigned int queue_index; + /* For virtio net, rx on [0], tx on [1], so the virtque + * can run on different threads. + */ + NetClientSource * nsrc[2]; }; typedef struct NICState { @@ -155,6 +177,9 @@ extern int default_net; extern const char *legacy_tftp_prefix; extern const char *legacy_bootp_filename; +void net_init_gsource(NetClientState *nc, int idx, NetClientSource *nsrc, + int fd, int events, Pollable rd, Pollable wr, GSourceFunc f, void *opaque); + int net_client_init(QemuOpts *opts, int is_netdev, Error **errp); int net_client_parse(QemuOptsList *opts_list, const char *str); int net_init_clients(void); @@ -190,4 +215,6 @@ unsigned compute_mcast_idx(const uint8_t *ep); .offset = vmstate_offset_macaddr(_state, _field), \ } +extern GSourceFuncs net_gsource_funcs; + #endif diff --git a/net/net.c b/net/net.c index f3d67f8..abe8fef 100644 --- a/net/net.c +++ b/net/net.c @@ -299,6 +299,12 @@ static void qemu_free_net_client(NetClientState *nc) } g_free(nc->name); g_free(nc->model); + if (nc->nsrc[0]) { + g_source_remove(g_source_get_id(&nc->nsrc[0]->source)); + } + if (nc->nsrc[1]) { + g_source_remove(g_source_get_id(&nc->nsrc[1]->source)); + } if (nc->destructor) { nc->destructor(nc); } @@ -558,6 +564,96 @@ qemu_sendv_packet(NetClientState *nc, const struct iovec *iov, int iovcnt) return qemu_sendv_packet_async(nc, iov, iovcnt, NULL); } +static gboolean prepare(GSource *src, gint *time) +{ + NetClientSource *nsrc = (NetClientSource *)src; + bool rd, wr, change = false; + + if (!nsrc->readable && !nsrc->writeable) { + return false; + } + if (nsrc->readable) { + rd = nsrc->readable(nsrc->opaque); + if (nsrc->last_rd_sts != rd) { + nsrc->last_rd_sts = rd; + change = true; + } + } + if (nsrc->writeable) { + wr = nsrc->writeable(nsrc->opaque); + if (nsrc->last_wr_sts != wr) { + nsrc->last_wr_sts = wr; + change = true; + } + } + if (!change) { + return false; + } + + g_source_remove_poll(src, &nsrc->gfd); + if (rd) { + nsrc->gfd.events |= G_IO_IN; + } else { + nsrc->gfd.events &= ~G_IO_IN; + } + if (wr) { + nsrc->gfd.events |= G_IO_OUT; + } else { + nsrc->gfd.events &= ~G_IO_OUT; + } + g_source_add_poll(src, &nsrc->gfd); + return false; +} + +static gboolean check(GSource *src) +{ + NetClientSource *nsrc = (NetClientSource *)src; + + if (nsrc->gfd.revents & nsrc->gfd.events) { + return true; + } + return false; +} + +static gboolean dispatch(GSource *src, GSourceFunc cb, gpointer data) +{ + gboolean ret = false; + + if (cb) { + ret = cb(data); + } + return ret; +} + +GSourceFuncs net_gsource_funcs = { + prepare, + check, + dispatch, + NULL +}; + +void net_init_gsource(NetClientState *nc, int idx, NetClientSource *nsrc, + int fd, int events, Pollable rd, Pollable wr, GSourceFunc f, void *opaque) +{ + nsrc->gfd.fd = fd; + nsrc->gfd.events = events; + nsrc->opaque = opaque; + nsrc->readable = rd; + nsrc->writeable = wr; + nsrc->last_rd_sts = false; + nsrc->last_wr_sts = false; + if (idx == 0) { + nc->nsrc[0] = nsrc; + } else { + nc->nsrc[1] = nsrc; + } + /* add PollFD if it wont change, otherwise left for GSource prepare */ + if (!rd && !wr) { + g_source_add_poll(&nsrc->source, &nsrc->gfd); + } + g_source_set_callback(&nsrc->source, f, nsrc, NULL); +} + NetClientState *qemu_find_netdev(const char *id) { NetClientState *nc; diff --git a/net/tap.c b/net/tap.c index daab350..0b663d1 100644 --- a/net/tap.c +++ b/net/tap.c @@ -70,25 +70,48 @@ static int tap_can_send(void *opaque); static void tap_send(void *opaque); static void tap_writable(void *opaque); -static void tap_update_fd_handler(TAPState *s) +static bool readable(void *opaque) { - qemu_set_fd_handler2(s->fd, - s->read_poll && s->enabled ? tap_can_send : NULL, - s->read_poll && s->enabled ? tap_send : NULL, - s->write_poll && s->enabled ? tap_writable : NULL, - s); + TAPState *s = (TAPState *)opaque; + + if (s->enabled && s->read_poll && + tap_can_send(s)) { + return true; + } + return false; +} + +static bool writeable(void *opaque) +{ + TAPState *s = (TAPState *)opaque; + + if (s->enabled && s->write_poll) { + return true; + } + return false; +} + +static gboolean tap_handler(gpointer data) +{ + NetClientSource *nsrc = (NetClientSource *)data; + + if (nsrc->gfd.revents & G_IO_IN) { + tap_send(nsrc->opaque); + } + if (nsrc->gfd.revents & G_IO_OUT) { + tap_writable(nsrc->opaque); + } + return true; } static void tap_read_poll(TAPState *s, bool enable) { s->read_poll = enable; - tap_update_fd_handler(s); } static void tap_write_poll(TAPState *s, bool enable) { s->write_poll = enable; - tap_update_fd_handler(s); } static void tap_writable(void *opaque) @@ -298,6 +321,7 @@ static void tap_cleanup(NetClientState *nc) static void tap_poll(NetClientState *nc, bool enable) { TAPState *s = DO_UPCAST(TAPState, nc, nc); + /* fixme, when tap backend on another thread, the disable should be sync */ tap_read_poll(s, enable); tap_write_poll(s, enable); } @@ -309,6 +333,11 @@ int tap_get_fd(NetClientState *nc) return s->fd; } +static void tap_bind_ctx(NetClientState *nc, GMainContext *ctx) +{ + g_source_attach(&nc->nsrc[0]->source, ctx); +} + /* fd support */ static NetClientInfo net_tap_info = { @@ -319,6 +348,7 @@ static NetClientInfo net_tap_info = { .receive_iov = tap_receive_iov, .poll = tap_poll, .cleanup = tap_cleanup, + .bind_ctx = tap_bind_ctx, }; static TAPState *net_tap_fd_init(NetClientState *peer, @@ -596,13 +626,18 @@ static int net_init_tap_one(const NetdevTapOptions *tap, NetClientState *peer, int vnet_hdr, int fd) { TAPState *s; + NetClientSource *nsrc; s = net_tap_fd_init(peer, model, name, fd, vnet_hdr); if (!s) { close(fd); return -1; } - + nsrc = (NetClientSource *)g_source_new(&net_gsource_funcs, + sizeof(NetClientSource)); + net_init_gsource(&s->nc, 0, nsrc, s->fd, G_IO_IN|G_IO_OUT, + readable, writeable, tap_handler, s); + s->nc.info->bind_ctx(&s->nc, NULL); if (tap_set_sndbuf(s->fd, tap) < 0) { return -1; } @@ -843,8 +878,8 @@ int tap_enable(NetClientState *nc) } else { ret = tap_fd_enable(s->fd); if (ret == 0) { + /*fixme, will be sync to ensure handler not be called */ s->enabled = true; - tap_update_fd_handler(s); } return ret; } @@ -861,8 +896,8 @@ int tap_disable(NetClientState *nc) ret = tap_fd_disable(s->fd); if (ret == 0) { qemu_purge_queued_packets(nc); + /*fixme, will be sync to ensure handler not be called */ s->enabled = false; - tap_update_fd_handler(s); } return ret; } -- 1.7.4.4