Re: [Qemu-devel] [PATCH for-3.2 33/41] slirp: replace qemu_notify_event() with a callback

[Samuel Thibault]

Marc-André Lureau, le mer. 14 nov. 2018 16:36:35 +0400, a ecrit:
> Use a "slirp socket" helper function to call the callback when
> sbdrop() returns true.

It's really far from clear what this should be doing :)

I'd say find out how to rephrase 86073017e384 ("slirp: Signal free input
buffer space to io-thread") in a generic way.

Samuel

[Qemu-devel] [PATCH for-3.2 33/41] slirp: replace qemu_notify_event() with a callback

[Marc-André Lureau]

Use a "slirp socket" helper function to call the callback when
sbdrop() returns true.

Signed-off-by: Marc-André Lureau 
---
 slirp/libslirp.h  | 1 +
 slirp/sbuf.h  | 2 +-
 slirp/socket.h| 1 +
 net/slirp.c   | 1 +
 slirp/sbuf.c  | 6 --
 slirp/socket.c| 7 +++
 slirp/tcp_input.c | 6 +++---
 7 files changed, 18 insertions(+), 6 deletions(-)

diff --git a/slirp/libslirp.h b/slirp/libslirp.h
index c7582e6516..7d04404340 100644
--- a/slirp/libslirp.h
+++ b/slirp/libslirp.h
@@ -22,6 +22,7 @@ typedef struct SlirpCb {
 void (*timer_mod)(void *timer, int64_t expire_timer);
 void (*set_nonblock)(int fd);
 void (*guest_error)(const char *msg);
+void (*notify)(void);
 } SlirpCb;
 
 
diff --git a/slirp/sbuf.h b/slirp/sbuf.h
index 644c201341..1cb9a42834 100644
--- a/slirp/sbuf.h
+++ b/slirp/sbuf.h
@@ -21,7 +21,7 @@ struct sbuf {
 };
 
 void sbfree(struct sbuf *);
-void sbdrop(struct sbuf *, int);
+bool sbdrop(struct sbuf *, int);
 void sbreserve(struct sbuf *, int);
 void sbappend(struct socket *, struct mbuf *);
 void sbcopy(struct sbuf *, int, int, char *);
diff --git a/slirp/socket.h b/slirp/socket.h
index 930ed95972..79b6fbd4c1 100644
--- a/slirp/socket.h
+++ b/slirp/socket.h
@@ -154,6 +154,7 @@ int soreadbuf(struct socket *so, const char *buf, int size);
 void sotranslate_out(struct socket *, struct sockaddr_storage *);
 void sotranslate_in(struct socket *, struct sockaddr_storage *);
 void sotranslate_accept(struct socket *);
+void sodrop(struct socket *, int num);
 
 
 #endif /* SLIRP_SOCKET_H */
diff --git a/net/slirp.c b/net/slirp.c
index b36092c948..4c39878933 100644
--- a/net/slirp.c
+++ b/net/slirp.c
@@ -198,6 +198,7 @@ static SlirpCb slirp_cb = {
 .timer_mod = net_slirp_timer_mod,
 .set_nonblock = qemu_set_nonblock,
 .guest_error = net_slirp_guest_error,
+.notify = qemu_notify_event,
 };
 
 static int net_slirp_init(NetClientState *peer, const char *model,
diff --git a/slirp/sbuf.c b/slirp/sbuf.c
index 912f235f65..17f28e97a6 100644
--- a/slirp/sbuf.c
+++ b/slirp/sbuf.c
@@ -17,7 +17,7 @@ sbfree(struct sbuf *sb)
free(sb->sb_data);
 }
 
-void
+bool
 sbdrop(struct sbuf *sb, int num)
 {
 int limit = sb->sb_datalen / 2;
@@ -34,8 +34,10 @@ sbdrop(struct sbuf *sb, int num)
sb->sb_rptr -= sb->sb_datalen;
 
 if (sb->sb_cc < limit && sb->sb_cc + num >= limit) {
-qemu_notify_event();
+return true;
 }
+
+return false;
 }
 
 void
diff --git a/slirp/socket.c b/slirp/socket.c
index 677fd20c9d..2b1b5052c4 100644
--- a/slirp/socket.c
+++ b/slirp/socket.c
@@ -928,3 +928,10 @@ void sotranslate_accept(struct socket *so)
 break;
 }
 }
+
+void sodrop(struct socket *s, int num)
+{
+if (sbdrop(>so_snd, num)) {
+s->slirp->cb->notify();
+}
+}
diff --git a/slirp/tcp_input.c b/slirp/tcp_input.c
index e33fb83df5..456d5829e7 100644
--- a/slirp/tcp_input.c
+++ b/slirp/tcp_input.c
@@ -527,7 +527,7 @@ findso:
SEQ_GT(ti->ti_ack, tp->t_rtseq))
tcp_xmit_timer(tp, tp->t_rtt);
acked = ti->ti_ack - tp->snd_una;
-   sbdrop(>so_snd, acked);
+   sodrop(so, acked);
tp->snd_una = ti->ti_ack;
m_free(m);
 
@@ -1140,10 +1140,10 @@ trimthenstep6:
}
if (acked > so->so_snd.sb_cc) {
tp->snd_wnd -= so->so_snd.sb_cc;
-   sbdrop(>so_snd, (int )so->so_snd.sb_cc);
+   sodrop(so, (int)so->so_snd.sb_cc);
ourfinisacked = 1;
} else {
-   sbdrop(>so_snd, acked);
+   sodrop(so, acked);
tp->snd_wnd -= acked;
ourfinisacked = 0;
}
-- 
2.19.1.708.g4ede3d42df