This patch adds a new function to the EAL API:
int rte_eal_primary_proc_alive(const char *path);
The function indicates if a primary process is alive right now.
This functionality is implemented by testing for a write-
lock on the config file, and the function tests for a lock.
The use case for this functionality is that a secondary
process can wait until a primary process starts by polling
the function and waiting. When the primary is running, the
secondary continues to poll to detect if the primary process
has quit unexpectedly, the secondary process can detect this.
The RTE_MAGIC number is written to the shared config by the
primary process, this is the signal to the secondary process
that the EAL is set up, and ready to be used. The function
rte_eal_mcfg_complete() writes RTE_MAGIC. This has been
delayed in the EAL init proceedure, as the PCI probing in
the primary process can interfere with the secondary running.
Signed-off-by: Harry van Haaren <harry.van.haaren at intel.com>
---
v2:
- Passing NULL as const char* uses default /var/run/.rte_config
- Moved code into /common/ instead of /linuxapp/, should work on BSD now
doc/guides/rel_notes/release_2_3.rst | 7 +++
lib/librte_eal/bsdapp/eal/Makefile | 1 +
lib/librte_eal/bsdapp/eal/rte_eal_version.map | 8 ++++
lib/librte_eal/common/eal_common_proc.c | 61 +++++++++++++++++++++++++
lib/librte_eal/common/include/rte_eal.h | 18 ++++++++
lib/librte_eal/linuxapp/eal/Makefile | 1 +
lib/librte_eal/linuxapp/eal/eal.c | 4 +-
lib/librte_eal/linuxapp/eal/rte_eal_version.map | 7 +++
8 files changed, 105 insertions(+), 2 deletions(-)
create mode 100644 lib/librte_eal/common/eal_common_proc.c
diff --git a/doc/guides/rel_notes/release_2_3.rst
b/doc/guides/rel_notes/release_2_3.rst
index 99de186..14b5b06 100644
--- a/doc/guides/rel_notes/release_2_3.rst
+++ b/doc/guides/rel_notes/release_2_3.rst
@@ -11,6 +11,13 @@ Resolved Issues
EAL
~~~
+* **Added rte_eal_primary_proc_alive() function**
+
+ A new function ``rte_eal_primary_proc_alive()`` has been added
+ to allow the user to detect if a primary process is running.
+ Use cases for this feature include fault detection, and monitoring
+ using secondary processes.
+
Drivers
~~~~~~~
diff --git a/lib/librte_eal/bsdapp/eal/Makefile
b/lib/librte_eal/bsdapp/eal/Makefile
index 65b293f..2d6e3b1 100644
--- a/lib/librte_eal/bsdapp/eal/Makefile
+++ b/lib/librte_eal/bsdapp/eal/Makefile
@@ -61,6 +61,7 @@ SRCS-$(CONFIG_RTE_LIBRTE_EAL_BSDAPP) += eal_alarm.c
# from common dir
SRCS-$(CONFIG_RTE_LIBRTE_EAL_BSDAPP) += eal_common_lcore.c
+SRCS-$(CONFIG_RTE_LIBRTE_EAL_BSDAPP) += eal_common_proc.c
SRCS-$(CONFIG_RTE_LIBRTE_EAL_BSDAPP) += eal_common_timer.c
SRCS-$(CONFIG_RTE_LIBRTE_EAL_BSDAPP) += eal_common_memzone.c
SRCS-$(CONFIG_RTE_LIBRTE_EAL_BSDAPP) += eal_common_log.c
diff --git a/lib/librte_eal/bsdapp/eal/rte_eal_version.map
b/lib/librte_eal/bsdapp/eal/rte_eal_version.map
index 9d7adf1..0e28017 100644
--- a/lib/librte_eal/bsdapp/eal/rte_eal_version.map
+++ b/lib/librte_eal/bsdapp/eal/rte_eal_version.map
@@ -135,3 +135,11 @@ DPDK_2.2 {
rte_xen_dom0_supported;
} DPDK_2.1;
+
+
+DPDK_2.3 {
+ global:
+
+ rte_eal_primary_proc_alive;
+
+} DPDK_2.2;
diff --git a/lib/librte_eal/common/eal_common_proc.c
b/lib/librte_eal/common/eal_common_proc.c
new file mode 100644
index 0000000..c598891
--- /dev/null
+++ b/lib/librte_eal/common/eal_common_proc.c
@@ -0,0 +1,61 @@
+/*-
+ * BSD LICENSE
+ *
+ * Copyright 2016 Intel Shannon Ltd. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ * * Neither the name of Intel Corporation nor the names of its
+ * contributors may be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <stdio.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <rte_eal.h>
+
+#include "eal_filesystem.h"
+#include "eal_internal_cfg.h"
+
+int
+rte_eal_primary_proc_alive(const char *config_file_path)
+{
+ int config_fd;
+
+ if (config_file_path)
+ config_fd = open(config_file_path, O_RDONLY);
+ else {
+ char default_path[PATH_MAX+1];
+ snprintf(default_path, PATH_MAX, RUNTIME_CONFIG_FMT,
+ default_config_dir, "rte");
+ config_fd = open(default_path, O_RDONLY);
+ }
+ if (config_fd < 0)
+ return 0;
+
+ int ret = lockf(config_fd, F_TEST, 0);
+ close(config_fd);
+
+ return !!ret;
+}
diff --git a/lib/librte_eal/common/include/rte_eal.h
b/lib/librte_eal/common/include/rte_eal.h
index d2816a8..05720ef 100644
--- a/lib/librte_eal/common/include/rte_eal.h
+++ b/lib/librte_eal/common/include/rte_eal.h
@@ -156,6 +156,24 @@ int rte_eal_iopl_init(void);
* - On failure, a negative error value.
*/
int rte_eal_init(int argc, char **argv);
+
+/**
+ * Check if a primary process is currently alive
+ *
+ * This function returns true when a primary process is currently
+ * active.
+ *
+ * @param config_file_path
+ * The config_file_path argument provided should point at the location
+ * that the primary process will create its config file. If NULL, the default
+ * config file path is used.
+ *
+ * @return
+ * - If alive, returns one.
+ * - If dead, returns zero.
+ */
+int rte_eal_primary_proc_alive(const char *config_file_path);
+
/**
* Usage function typedef used by the application usage function.
*
diff --git a/lib/librte_eal/linuxapp/eal/Makefile
b/lib/librte_eal/linuxapp/eal/Makefile
index 26eced5..6df0d58 100644
--- a/lib/librte_eal/linuxapp/eal/Makefile
+++ b/lib/librte_eal/linuxapp/eal/Makefile
@@ -71,6 +71,7 @@ endif
# from common dir
SRCS-$(CONFIG_RTE_LIBRTE_EAL_LINUXAPP) += eal_common_lcore.c
+SRCS-$(CONFIG_RTE_LIBRTE_EAL_LINUXAPP) += eal_common_proc.c
SRCS-$(CONFIG_RTE_LIBRTE_EAL_LINUXAPP) += eal_common_timer.c
SRCS-$(CONFIG_RTE_LIBRTE_EAL_LINUXAPP) += eal_common_memzone.c
SRCS-$(CONFIG_RTE_LIBRTE_EAL_LINUXAPP) += eal_common_log.c
diff --git a/lib/librte_eal/linuxapp/eal/eal.c
b/lib/librte_eal/linuxapp/eal/eal.c
index 635ec36..c261fc0 100644
--- a/lib/librte_eal/linuxapp/eal/eal.c
+++ b/lib/librte_eal/linuxapp/eal/eal.c
@@ -818,8 +818,6 @@ rte_eal_init(int argc, char **argv)
eal_check_mem_on_local_socket();
- rte_eal_mcfg_complete();
-
if (eal_plugins_init() < 0)
rte_panic("Cannot init plugins\n");
@@ -877,6 +875,8 @@ rte_eal_init(int argc, char **argv)
if (rte_eal_pci_probe())
rte_panic("Cannot probe PCI\n");
+ rte_eal_mcfg_complete();
+
return fctret;
}
diff --git a/lib/librte_eal/linuxapp/eal/rte_eal_version.map
b/lib/librte_eal/linuxapp/eal/rte_eal_version.map
index cbe175f..7a8c530 100644
--- a/lib/librte_eal/linuxapp/eal/rte_eal_version.map
+++ b/lib/librte_eal/linuxapp/eal/rte_eal_version.map
@@ -138,3 +138,10 @@ DPDK_2.2 {
rte_xen_dom0_supported;
} DPDK_2.1;
+
+DPDK_2.3 {
+ global:
+
+ rte_eal_primary_proc_alive;
+
+} DPDK_2.2;
--
2.5.0
