On 8/10/22 12:52, Richard Biener wrote:
> If it's not a template and the methods not inline won't we get multiple
> definition errors when this include file is included in multiple places
> from an executable? opts-common.cc might be a good place to
> stuff it, and opts.h to declare (if it were not for std::string, so possibly
> jobserver.h is good enough, or opts-jobserver.h?)
Works for me, updated in v2.
Martin
From ff2073e1f549df40a5e859e2cde9a403307c1960 Mon Sep 17 00:00:00 2001
From: Martin Liska <mli...@suse.cz>
Date: Tue, 9 Aug 2022 13:59:39 +0200
Subject: [PATCH 3/3] lto: respect jobserver in parallel WPA streaming
PR lto/106328
gcc/ChangeLog:
* opts-jobserver.h (struct jobserver_info): Add pipefd.
(jobserver_info::connect): New.
(jobserver_info::disconnect): Likewise.
(jobserver_info::get_token): Likewise.
(jobserver_info::return_token): Likewise.
* opts-common.cc: Implement the new functions.
gcc/lto/ChangeLog:
* lto.cc (wait_for_child): Decrement nruns once a process
finishes.
(stream_out_partitions): Use job server if active.
(do_whole_program_analysis): Likewise.
---
gcc/lto/lto.cc | 58 +++++++++++++++++++++++++++++++++-----------
gcc/opts-common.cc | 42 ++++++++++++++++++++++++++++++++
gcc/opts-jobserver.h | 14 +++++++++++
3 files changed, 100 insertions(+), 14 deletions(-)
diff --git a/gcc/lto/lto.cc b/gcc/lto/lto.cc
index 31b0c1862f7..c82307f4f7e 100644
--- a/gcc/lto/lto.cc
+++ b/gcc/lto/lto.cc
@@ -18,6 +18,7 @@ You should have received a copy of the GNU General Public License
along with GCC; see the file COPYING3. If not see
<http://www.gnu.org/licenses/>. */
+#define INCLUDE_STRING
#include "config.h"
#include "system.h"
#include "coretypes.h"
@@ -54,11 +55,17 @@ along with GCC; see the file COPYING3. If not see
#include "attribs.h"
#include "builtins.h"
#include "lto-common.h"
+#include "opts-jobserver.h"
-
-/* Number of parallel tasks to run, -1 if we want to use GNU Make jobserver. */
+/* Number of parallel tasks to run. */
static int lto_parallelism;
+/* Number of active WPA streaming processes. */
+static int nruns = 0;
+
+/* GNU make's jobserver info. */
+static jobserver_info *jinfo = NULL;
+
/* Return true when NODE has a clone that is analyzed (i.e. we need
to load its body even if the node itself is not needed). */
@@ -205,6 +212,12 @@ wait_for_child ()
"streaming subprocess was killed by signal");
}
while (!WIFEXITED (status) && !WIFSIGNALED (status));
+
+ --nruns;
+
+ /* Return token to the jobserver if active. */
+ if (jinfo != NULL && jinfo->is_active)
+ jinfo->return_token ();
}
#endif
@@ -228,25 +241,35 @@ stream_out_partitions (char *temp_filename, int blen, int min, int max,
bool ARG_UNUSED (last))
{
#ifdef HAVE_WORKING_FORK
- static int nruns;
-
if (lto_parallelism <= 1)
{
stream_out_partitions_1 (temp_filename, blen, min, max);
return;
}
- /* Do not run more than LTO_PARALLELISM streamings
- FIXME: we ignore limits on jobserver. */
if (lto_parallelism > 0 && nruns >= lto_parallelism)
- {
- wait_for_child ();
- nruns --;
- }
+ wait_for_child ();
+
/* If this is not the last parallel partition, execute new
streaming process. */
if (!last)
{
+ if (jinfo != NULL && jinfo->is_active)
+ while (true)
+ {
+ if (jinfo->get_token ())
+ break;
+ if (nruns > 0)
+ wait_for_child ();
+ else
+ {
+ /* There are no free tokens, lets do the job outselves. */
+ stream_out_partitions_1 (temp_filename, blen, min, max);
+ asm_nodes_output = true;
+ return;
+ }
+ }
+
pid_t cpid = fork ();
if (!cpid)
@@ -264,10 +287,12 @@ stream_out_partitions (char *temp_filename, int blen, int min, int max,
/* Last partition; stream it and wait for all children to die. */
else
{
- int i;
stream_out_partitions_1 (temp_filename, blen, min, max);
- for (i = 0; i < nruns; i++)
+ while (nruns > 0)
wait_for_child ();
+
+ if (jinfo != NULL && jinfo->is_active)
+ jinfo->disconnect ();
}
asm_nodes_output = true;
#else
@@ -460,9 +485,14 @@ do_whole_program_analysis (void)
lto_parallelism = 1;
- /* TODO: jobserver communication is not supported, yet. */
if (!strcmp (flag_wpa, "jobserver"))
- lto_parallelism = param_max_lto_streaming_parallelism;
+ {
+ jinfo = new jobserver_info ();
+ if (jinfo->is_active)
+ jinfo->connect ();
+
+ lto_parallelism = param_max_lto_streaming_parallelism;
+ }
else
{
lto_parallelism = atoi (flag_wpa);
diff --git a/gcc/opts-common.cc b/gcc/opts-common.cc
index c2993f9140a..6c9355f6372 100644
--- a/gcc/opts-common.cc
+++ b/gcc/opts-common.cc
@@ -2059,3 +2059,45 @@ jobserver_info::jobserver_info ()
if (!error_msg.empty ())
error_msg = "jobserver is not available: " + error_msg;
}
+
+void
+jobserver_info::connect ()
+{
+ if (!pipe_path.empty ())
+ pipefd = open (pipe_path.c_str (), O_RDWR);
+}
+
+void
+jobserver_info::disconnect ()
+{
+ if (!pipe_path.empty ())
+ {
+ gcc_assert (close (pipefd) == 0);
+ pipefd = -1;
+ }
+}
+
+bool
+jobserver_info::get_token ()
+{
+ int fd = pipe_path.empty () ? rfd : pipefd;
+ char c;
+ unsigned n = read (fd, &c, 1);
+ if (n != 1)
+ {
+ gcc_assert (errno == EAGAIN);
+ return false;
+ }
+ else
+ return true;
+}
+
+void
+jobserver_info::return_token ()
+{
+ int fd = pipe_path.empty () ? wfd : pipefd;
+ char c = 'G';
+ gcc_assert (write (fd, &c, 1) == 1);
+}
+
+
diff --git a/gcc/opts-jobserver.h b/gcc/opts-jobserver.h
index 98ea2579962..76c1d9b2882 100644
--- a/gcc/opts-jobserver.h
+++ b/gcc/opts-jobserver.h
@@ -29,6 +29,18 @@ struct jobserver_info
/* Default constructor. */
jobserver_info ();
+ /* Connect to the server. */
+ void connect ();
+
+ /* Disconnect from the server. */
+ void disconnect ();
+
+ /* Get token from the server. */
+ bool get_token ();
+
+ /* Return token to the server. */
+ void return_token ();
+
/* Error message if there is a problem. */
string error_msg = "";
/* Skipped MAKEFLAGS where --jobserver-auth is skipped. */
@@ -39,6 +51,8 @@ struct jobserver_info
int wfd = -1;
/* Named pipe path. */
string pipe_path = "";
+ /* Pipe file descriptor. */
+ int pipefd = -1;
/* Return true if jobserver is active. */
bool is_active = false;
};
--
2.37.1
