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-rw-r--r--erts/emulator/beam/erl_alloc.types2
-rw-r--r--erts/emulator/sys/unix/sys.c230
2 files changed, 217 insertions, 15 deletions
diff --git a/erts/emulator/beam/erl_alloc.types b/erts/emulator/beam/erl_alloc.types
index 17ac6316b7..d23d26a0fc 100644
--- a/erts/emulator/beam/erl_alloc.types
+++ b/erts/emulator/beam/erl_alloc.types
@@ -411,6 +411,8 @@ type CS_PROG_PATH LONG_LIVED SYSTEM cs_prog_path
type ENVIRONMENT TEMPORARY SYSTEM environment
type PUTENV_STR SYSTEM SYSTEM putenv_string
type PRT_REP_EXIT STANDARD SYSTEM port_report_exit
+type SYS_BLOCKING STANDARD SYSTEM sys_blocking
+type SYS_WRITE_BUF TEMPORARY SYSTEM sys_write_buf
+endif
diff --git a/erts/emulator/sys/unix/sys.c b/erts/emulator/sys/unix/sys.c
index ad8b60fe7c..eed93cb2a0 100644
--- a/erts/emulator/sys/unix/sys.c
+++ b/erts/emulator/sys/unix/sys.c
@@ -92,8 +92,10 @@ static erts_smp_rwmtx_t environ_rwmtx;
# else
# define CHLDWTHR 0
# endif
+# define FDBLOCK 1
#else
# define CHLDWTHR 0
+# define FDBLOCK 0
#endif
/*
* [OTP-3906]
@@ -122,6 +124,15 @@ struct ErtsSysReportExit_ {
#endif
};
+/* Used by the fd driver iff the fd could not be set to non-blocking */
+typedef struct ErtsSysBlocking_ {
+ ErlDrvPDL pdl;
+ int res;
+ int err;
+ unsigned int pkey;
+} ErtsSysBlocking;
+
+
/* This data is shared by these drivers - initialized by spawn_init() */
static struct driver_data {
ErlDrvPort port_num;
@@ -130,6 +141,8 @@ static struct driver_data {
int pid;
int alive;
int status;
+ int terminating;
+ ErtsSysBlocking *blocking;
} *driver_data; /* indexed by fd */
static ErtsSysReportExit *report_exit_list;
@@ -1109,11 +1122,16 @@ void fini_getenv_state(GETENV_STATE *state)
/* Driver interfaces */
static ErlDrvData spawn_start(ErlDrvPort, char*, SysDriverOpts*);
static ErlDrvData fd_start(ErlDrvPort, char*, SysDriverOpts*);
+#if FDBLOCK
+static void fd_async(void *);
+static void fd_ready_async(ErlDrvData drv_data, ErlDrvThreadData thread_data);
+#endif
static ErlDrvSSizeT fd_control(ErlDrvData, unsigned int, char *, ErlDrvSizeT,
char **, ErlDrvSizeT);
static ErlDrvData vanilla_start(ErlDrvPort, char*, SysDriverOpts*);
static int spawn_init(void);
static void fd_stop(ErlDrvData);
+static void fd_flush(ErlDrvData);
static void stop(ErlDrvData);
static void ready_input(ErlDrvData, ErlDrvEvent);
static void ready_output(ErlDrvData, ErlDrvEvent);
@@ -1158,8 +1176,12 @@ struct erl_drv_entry fd_driver_entry = {
fd_control,
NULL,
outputv,
- NULL, /* ready_async */
- NULL, /* flush */
+#if FDBLOCK
+ fd_ready_async, /* ready_async */
+#else
+ NULL,
+#endif
+ fd_flush, /* flush */
NULL, /* call */
NULL, /* event */
ERL_DRV_EXTENDED_MARKER,
@@ -1213,13 +1235,28 @@ static RETSIGTYPE onchld(int signum)
#endif
}
+static int set_blocking_data(struct driver_data *dd) {
+
+ dd->blocking = erts_alloc(ERTS_ALC_T_SYS_BLOCKING, sizeof(ErtsSysBlocking));
+
+ erts_smp_atomic_add_nob(&sys_misc_mem_sz, sizeof(ErtsSysBlocking));
+
+ dd->blocking->pdl = driver_pdl_create(dd->port_num);
+ dd->blocking->res = 0;
+ dd->blocking->err = 0;
+ dd->blocking->pkey = driver_async_port_key(dd->port_num);
+
+ return 1;
+}
+
static int set_driver_data(ErlDrvPort port_num,
int ifd,
int ofd,
int packet_bytes,
int read_write,
int exit_status,
- int pid)
+ int pid,
+ int is_blocking)
{
Port *prt;
ErtsSysReportExit *report_exit;
@@ -1251,8 +1288,13 @@ static int set_driver_data(ErlDrvPort port_num,
driver_data[ifd].pid = pid;
driver_data[ifd].alive = 1;
driver_data[ifd].status = 0;
+ driver_data[ifd].terminating = 0;
+ driver_data[ifd].blocking = NULL;
if (read_write & DO_WRITE) {
driver_data[ifd].ofd = ofd;
+ if (is_blocking && FDBLOCK)
+ if (!set_blocking_data(driver_data+ifd))
+ return -1;
if (ifd != ofd)
driver_data[ofd] = driver_data[ifd]; /* structure copy */
} else { /* DO_READ only */
@@ -1268,6 +1310,11 @@ static int set_driver_data(ErlDrvPort port_num,
driver_data[ofd].pid = pid;
driver_data[ofd].alive = 1;
driver_data[ofd].status = 0;
+ driver_data[ofd].terminating = 0;
+ driver_data[ofd].blocking = NULL;
+ if (is_blocking && FDBLOCK)
+ if (!set_blocking_data(driver_data+ofd))
+ return -1;
return(ofd);
}
}
@@ -1277,6 +1324,7 @@ static int spawn_init()
int i;
#if CHLDWTHR
erts_thr_opts_t thr_opts = ERTS_THR_OPTS_DEFAULT_INITER;
+
thr_opts.detached = 0;
thr_opts.suggested_stack_size = 0; /* Smallest possible */
#endif
@@ -1756,7 +1804,7 @@ static ErlDrvData spawn_start(ErlDrvPort port_num, char* name, SysDriverOpts* op
}
res = set_driver_data(port_num, ifd[0], ofd[1], opts->packet_bytes,
- opts->read_write, opts->exit_status, pid);
+ opts->read_write, opts->exit_status, pid, 0);
/* Don't unblock SIGCHLD until now, since the call above must
first complete putting away the info about our new subprocess. */
unblock_signals();
@@ -1841,6 +1889,7 @@ static ErlDrvData fd_start(ErlDrvPort port_num, char* name,
SysDriverOpts* opts)
{
ErlDrvData res;
+ int non_blocking = 0;
if (((opts->read_write & DO_READ) && opts->ifd >= max_files) ||
((opts->read_write & DO_WRITE) && opts->ofd >= max_files))
@@ -1913,6 +1962,20 @@ static ErlDrvData fd_start(ErlDrvPort port_num, char* name,
* case - it can be called with any old pre-existing file descriptors,
* the relations between which (if they're even two) we can only guess
* at - still, we try our best...
+ *
+ * Added note OTP 18: Some systems seem to use stdout/stderr to log data
+ * using unix pipes, so we cannot allow the system to block on a write.
+ * Therefore we use an async thread to write the data to fd's that could
+ * not be set to non-blocking. When no async threads are available we
+ * fall back on the old behaviour.
+ *
+ * Also the guarantee about what is delivered to the OS has changed.
+ * Pre 18 the fd driver did no flushing of data before terminating.
+ * Now it does. This is because we want to be able to guarantee that things
+ * such as escripts and friends really have outputted all data before
+ * terminating. This could potentially block the termination of the system
+ * for a very long time, but if the user wants to terminate fast she should
+ * use erlang:halt with flush=false.
*/
if (opts->read_write & DO_READ) {
@@ -1935,6 +1998,7 @@ static ErlDrvData fd_start(ErlDrvPort port_num, char* name,
imagine a scenario where setting non-blocking mode
here would cause problems - go ahead and do it. */
+ non_blocking = 1;
SET_NONBLOCKING(opts->ofd);
} else { /* output fd is a tty, input fd isn't */
@@ -1977,6 +2041,7 @@ static ErlDrvData fd_start(ErlDrvPort port_num, char* name,
(nfd = open(tty, O_WRONLY)) != -1) {
dup2(nfd, opts->ofd);
close(nfd);
+ non_blocking = 1;
SET_NONBLOCKING(opts->ofd);
}
}
@@ -1985,8 +2050,9 @@ static ErlDrvData fd_start(ErlDrvPort port_num, char* name,
}
CHLD_STAT_LOCK;
res = (ErlDrvData)(long)set_driver_data(port_num, opts->ifd, opts->ofd,
- opts->packet_bytes,
- opts->read_write, 0, -1);
+ opts->packet_bytes,
+ opts->read_write, 0, -1,
+ !non_blocking);
CHLD_STAT_UNLOCK;
return res;
}
@@ -2012,14 +2078,30 @@ static void nbio_stop_fd(ErlDrvPort prt, int fd)
SET_BLOCKING(fd);
}
-static void fd_stop(ErlDrvData fd) /* Does not close the fds */
+static void fd_stop(ErlDrvData ev) /* Does not close the fds */
{
int ofd;
+ int fd = (int)(long)ev;
+ ErlDrvPort prt = driver_data[fd].port_num;
- nbio_stop_fd(driver_data[(int)(long)fd].port_num, (int)(long)fd);
- ofd = driver_data[(int)(long)fd].ofd;
- if (ofd != (int)(long)fd && ofd != -1)
- nbio_stop_fd(driver_data[(int)(long)fd].port_num, (int)(long)ofd);
+#if FDBLOCK
+ if (driver_data[fd].blocking) {
+ erts_free(ERTS_ALC_T_SYS_BLOCKING,driver_data[fd].blocking);
+ driver_data[fd].blocking = NULL;
+ erts_smp_atomic_add_nob(&sys_misc_mem_sz, -1*sizeof(ErtsSysBlocking));
+ }
+#endif
+
+ nbio_stop_fd(prt, fd);
+ ofd = driver_data[fd].ofd;
+ if (ofd != fd && ofd != -1)
+ nbio_stop_fd(prt, ofd);
+}
+
+static void fd_flush(ErlDrvData fd)
+{
+ if (!driver_data[(int)(long)fd].terminating)
+ driver_data[(int)(long)fd].terminating = 1;
}
static ErlDrvData vanilla_start(ErlDrvPort port_num, char* name,
@@ -2042,8 +2124,8 @@ static ErlDrvData vanilla_start(ErlDrvPort port_num, char* name,
CHLD_STAT_LOCK;
res = (ErlDrvData)(long)set_driver_data(port_num, fd, fd,
- opts->packet_bytes,
- opts->read_write, 0, -1);
+ opts->packet_bytes,
+ opts->read_write, 0, -1, 0);
CHLD_STAT_UNLOCK;
return res;
}
@@ -2080,6 +2162,7 @@ static void stop(ErlDrvData fd)
}
}
+/* used by fd_driver */
static void outputv(ErlDrvData e, ErlIOVec* ev)
{
int fd = (int)(long)e;
@@ -2105,12 +2188,21 @@ static void outputv(ErlDrvData e, ErlIOVec* ev)
ev->iov[0].iov_base = lbp;
ev->iov[0].iov_len = pb;
ev->size += pb;
+
+ if (driver_data[fd].blocking && FDBLOCK)
+ driver_pdl_lock(driver_data[fd].blocking->pdl);
+
if ((sz = driver_sizeq(ix)) > 0) {
driver_enqv(ix, ev, 0);
+
+ if (driver_data[fd].blocking && FDBLOCK)
+ driver_pdl_unlock(driver_data[fd].blocking->pdl);
+
if (sz + ev->size >= (1 << 13))
set_busy_port(ix, 1);
}
- else {
+ else if (!driver_data[fd].blocking || !FDBLOCK) {
+ /* We try to write directly if the fd in non-blocking */
int vsize = ev->vsize > MAX_VSIZE ? MAX_VSIZE : ev->vsize;
n = writev(ofd, (const void *) (ev->iov), vsize);
@@ -2126,10 +2218,22 @@ static void outputv(ErlDrvData e, ErlIOVec* ev)
driver_enqv(ix, ev, n); /* n is the skip value */
driver_select(ix, ofd, ERL_DRV_WRITE|ERL_DRV_USE, 1);
}
+#if FDBLOCK
+ else {
+ if (ev->size != 0) {
+ driver_enqv(ix, ev, 0);
+ driver_pdl_unlock(driver_data[fd].blocking->pdl);
+ driver_async(ix, &driver_data[fd].blocking->pkey,
+ fd_async, driver_data+fd, NULL);
+ } else {
+ driver_pdl_unlock(driver_data[fd].blocking->pdl);
+ }
+ }
+#endif
/* return 0;*/
}
-
+/* Used by spawn_driver and vanilla driver */
static void output(ErlDrvData e, char* buf, ErlDrvSizeT len)
{
int fd = (int)(long)e;
@@ -2192,6 +2296,23 @@ static int port_inp_failure(ErlDrvPort port_num, int ready_fd, int res)
ASSERT(res <= 0);
(void) driver_select(port_num, ready_fd, ERL_DRV_READ|ERL_DRV_WRITE, 0);
clear_fd_data(ready_fd);
+
+ if (driver_data[ready_fd].blocking && FDBLOCK) {
+ driver_pdl_lock(driver_data[ready_fd].blocking->pdl);
+ if (driver_sizeq(driver_data[ready_fd].port_num) > 0) {
+ driver_pdl_unlock(driver_data[ready_fd].blocking->pdl);
+ /* We have stuff in the output queue, so we just
+ set the state to terminating and wait for fd_async_ready
+ to terminate the port */
+ if (res == 0)
+ driver_data[ready_fd].terminating = 2;
+ else
+ driver_data[ready_fd].terminating = -err;
+ return 0;
+ }
+ driver_pdl_unlock(driver_data[ready_fd].blocking->pdl);
+ }
+
if (res == 0) {
if (driver_data[ready_fd].report_exit) {
CHLD_STAT_LOCK;
@@ -2242,6 +2363,7 @@ static void ready_input(ErlDrvData e, ErlDrvEvent ready_fd)
port_num = driver_data[fd].port_num;
packet_bytes = driver_data[fd].packet_bytes;
+
if (packet_bytes == 0) {
byte *read_buf = (byte *) erts_alloc(ERTS_ALC_T_SYS_READ_BUF,
ERTS_SYS_READ_BUF_SZ);
@@ -2365,6 +2487,8 @@ static void ready_output(ErlDrvData e, ErlDrvEvent ready_fd)
if ((iv = (struct iovec*) driver_peekq(ix, &vsize)) == NULL) {
driver_select(ix, ready_fd, ERL_DRV_WRITE, 0);
+ if (driver_data[fd].terminating)
+ driver_failure_atom(driver_data[fd].port_num,"normal");
return; /* 0; */
}
vsize = vsize > MAX_VSIZE ? MAX_VSIZE : vsize;
@@ -2390,6 +2514,82 @@ static void stop_select(ErlDrvEvent fd, void* _)
close((int)fd);
}
+#if FDBLOCK
+
+static void
+fd_async(void *async_data)
+{
+ int res;
+ struct driver_data *dd = (struct driver_data*)async_data;
+ SysIOVec *iov0;
+ SysIOVec *iov;
+ int iovlen;
+ int iovcnt;
+ int p;
+ /* much of this code is stolen from efile_drv:invoke_writev */
+ driver_pdl_lock(dd->blocking->pdl);
+ iov0 = driver_peekq(dd->port_num, &iovlen);
+ /* Calculate iovcnt */
+ for (p = 0, iovcnt = 0; iovcnt < iovlen;
+ p += iov0[iovcnt++].iov_len)
+ ;
+ iov = erts_alloc_fnf(ERTS_ALC_T_SYS_WRITE_BUF,
+ sizeof(SysIOVec)*iovcnt);
+ if (!iov) {
+ res = -1;
+ errno = ENOMEM;
+ erts_free(ERTS_ALC_T_SYS_WRITE_BUF, iov);
+ driver_pdl_unlock(dd->blocking->pdl);
+ } else {
+ memcpy(iov,iov0,iovcnt*sizeof(SysIOVec));
+ driver_pdl_unlock(dd->blocking->pdl);
+
+ res = writev(dd->ofd, iov, iovlen);
+
+ erts_free(ERTS_ALC_T_SYS_WRITE_BUF, iov);
+ }
+ dd->blocking->res = res;
+ dd->blocking->err = errno;
+}
+
+void fd_ready_async(ErlDrvData drv_data,
+ ErlDrvThreadData thread_data) {
+ struct driver_data *dd = (struct driver_data *)thread_data;
+ ErlDrvPort port_num = dd->port_num;
+
+ ASSERT(dd->blocking);
+ ASSERT(dd == (driver_data + (int)(long)drv_data));
+
+ if (dd->blocking->res > 0) {
+ driver_pdl_lock(dd->blocking->pdl);
+ if (driver_deq(port_num, dd->blocking->res) == 0) {
+ driver_pdl_unlock(dd->blocking->pdl);
+ set_busy_port(port_num, 0);
+ if (dd->terminating) {
+ /* The port is has been ordered to terminate
+ from either fd_flush or port_inp_failure */
+ if (dd->terminating == 1)
+ driver_failure_atom(port_num, "normal");
+ else if (dd->terminating == 2)
+ driver_failure_eof(port_num);
+ else if (dd->terminating < 0)
+ driver_failure_posix(port_num, -dd->terminating);
+ return; /* -1; */
+ }
+ } else {
+ driver_pdl_unlock(dd->blocking->pdl);
+ /* still data left to write in queue */
+ driver_async(port_num, &dd->blocking->pkey, fd_async, dd, NULL);
+ return /* 0; */;
+ }
+ } else if (dd->blocking->res < 0) {
+ driver_failure_posix(port_num, dd->blocking->err);
+ return; /* -1; */
+ }
+ return; /* 0; */
+}
+
+#endif
void erts_do_break_handling(void)
{
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-28 06:57:11 +0000