Debugging an issue where pettycoin would become unresponsive, I discovered
this:
poll([{fd=5, events=POLLIN}, {fd=19, events=POLLIN}, {fd=6, events=POLLIN}, {fd=15, events=POLLIN}, {fd=8, events=POLLIN}, {fd=-11}, {fd=7, events=POLL
OUT}], 7, -1) = 1 ([{fd=7, revents=POLLOUT}]) <0.000014>
write(7, "\224]\4\0\4\0\0\0\200\203\16\234\v\262\276\321h\357\217Y\0\204\21\31\253\304#U\0206}\20"..., 286100) = 159280 <98.894019>
Despite poll saying the (TCP socket) fd was ready, the write took 98 seconds!
The results were far more reasonable with O_NONBLOCK:
write(9, "%\247l0\337^\216\24\323\2705\203Y\340h\2767/bM\373?dM\254\22g\310\v\0\0\0"..., 206460) = 40544 <0.000052>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
backend_new_plan(conn);
}
backend_new_plan(conn);
}
+static void set_blocking(int fd, bool block)
+{
+ int flags = fcntl(fd, F_GETFL);
+
+ if (block)
+ flags &= ~O_NONBLOCK;
+ else
+ flags |= O_NONBLOCK;
+
+ fcntl(fd, F_SETFL, flags);
+}
+
struct io_conn *io_new_conn_(const tal_t *ctx, int fd,
struct io_plan *(*init)(struct io_conn *, void *),
void *arg)
struct io_conn *io_new_conn_(const tal_t *ctx, int fd,
struct io_plan *(*init)(struct io_conn *, void *),
void *arg)
if (!add_conn(conn))
return tal_free(conn);
if (!add_conn(conn))
return tal_free(conn);
+ /* Keep our I/O async. */
+ set_blocking(fd, false);
+
/* We start with out doing nothing, and in doing our init. */
conn->plan[IO_OUT].status = IO_UNSET;
/* We start with out doing nothing, and in doing our init. */
conn->plan[IO_OUT].status = IO_UNSET;
return -1;
if (err == 0) {
return -1;
if (err == 0) {
- /* Restore blocking if it was initially. */
- fcntl(fd, F_SETFL, arg->u1.s);
return 1;
} else if (err == EINPROGRESS)
return 0;
return 1;
} else if (err == EINPROGRESS)
return 0;
struct io_plan *(*next)(struct io_conn *, void *),
void *next_arg)
{
struct io_plan *(*next)(struct io_conn *, void *),
void *next_arg)
{
- struct io_plan_arg *arg = io_plan_arg(conn, IO_IN);
int fd = io_conn_fd(conn);
int fd = io_conn_fd(conn);
- /* Save old flags, set nonblock if not already. */
- arg->u1.s = fcntl(fd, F_GETFL);
- fcntl(fd, F_SETFL, arg->u1.s | O_NONBLOCK);
+ /* We don't actually need the arg, but we need it polling. */
+ io_plan_arg(conn, IO_OUT);
+
+ /* Note that io_new_conn() will make fd O_NONBLOCK */
/* Immediate connect can happen. */
if (connect(fd, addr->ai_addr, addr->ai_addrlen) == 0)
/* Immediate connect can happen. */
if (connect(fd, addr->ai_addr, addr->ai_addrlen) == 0)
- return set_always(conn, IO_IN, next, next_arg);
+ return set_always(conn, IO_OUT, next, next_arg);
if (errno != EINPROGRESS)
return io_close(conn);
if (errno != EINPROGRESS)
return io_close(conn);
- return io_set_plan(conn, IO_IN, do_connect, next, next_arg);
+ return io_set_plan(conn, IO_OUT, do_connect, next, next_arg);
}
static struct io_plan *io_wait_dir(struct io_conn *conn,
}
static struct io_plan *io_wait_dir(struct io_conn *conn,
/* We can't sync debug until we've set both: io_wait() and io_always
* can't handle it. */
conn->debug_saved = conn->debug;
/* We can't sync debug until we've set both: io_wait() and io_always
* can't handle it. */
conn->debug_saved = conn->debug;
+ io_set_debug(conn, false);
}
struct io_plan *io_duplex_(struct io_plan *in_plan, struct io_plan *out_plan)
}
struct io_plan *io_duplex_(struct io_plan *in_plan, struct io_plan *out_plan)
/* Restore debug. */
conn = container_of(in_plan, struct io_conn, plan[IO_IN]);
/* Restore debug. */
conn = container_of(in_plan, struct io_conn, plan[IO_IN]);
- conn->debug = conn->debug_saved;
+ io_set_debug(conn, conn->debug_saved);
/* Now set the plans again, to invoke sync debug. */
io_set_plan(conn, IO_OUT,
/* Now set the plans again, to invoke sync debug. */
io_set_plan(conn, IO_OUT,
void io_set_debug(struct io_conn *conn, bool debug)
{
conn->debug = debug;
void io_set_debug(struct io_conn *conn, bool debug)
{
conn->debug = debug;
+
+ /* Debugging means fds must block. */
+ set_blocking(io_conn_fd(conn), debug);
}
void io_debug_complete(struct io_conn *conn)
}
void io_debug_complete(struct io_conn *conn)