[dpdk-dev] [PATCH] eal: fix recording of detected/enabled logical cores

[Thomas Monjalon <thomas.monjalon@6wind.com>]

From: Ivan Boule <ivan.boule@6wind.com>

1) In the EAL initialization phase, invoke the function rte_eal_cpu_init
   to detect the set of running cores (and enable them by default) before
   processing the [enabled] core mask option that is performed during the
   parsing of EAL arguments.

2) In the function rte_eal_cpu_init():
   - to parse the set of all running logical cores on the machine, do not
     use the RTE_LCORE_FOREACH macro that considers the set of already
     detected cores...
     Instead, use a standard loop based on the RTE_MAX_LCORE constant.
   - explicitely set to ROLE_RTE the role of each detected logical core
     that is recorded in the EAL configuration, as all running cores are
     enabled by default.

3) In the function eal_parse_coremask(), update the "lcore_count" field
   of the EAL configuration with the effective number of logical cores
   that are set in the mask of enabled logical cores.

Signed-off-by: Ivan Boule <ivan.boule@6wind.com>
---
 lib/librte_eal/linuxapp/eal/eal.c       |    8 +++++---
 lib/librte_eal/linuxapp/eal/eal_lcore.c |   12 ++++++++----
 2 files changed, 13 insertions(+), 7 deletions(-)

diff --git a/lib/librte_eal/linuxapp/eal/eal.c b/lib/librte_eal/linuxapp/eal/eal.c
index d94c6bb..ed0e9b1 100644
--- a/lib/librte_eal/linuxapp/eal/eal.c
+++ b/lib/librte_eal/linuxapp/eal/eal.c
@@ -389,6 +389,8 @@ eal_parse_coremask(const char *coremask)
 			cfg->lcore_role[i] = ROLE_OFF;
 		}
 	}
+	/* Update the count of enabled logical cores of the EAL configuration */
+	cfg->lcore_count = count;
 	return 0;
 }
 
@@ -817,6 +819,9 @@ rte_eal_init(int argc, char **argv)
 	if (rte_eal_log_early_init() < 0)
 		rte_panic("Cannot init early logs\n");
 
+	if (rte_eal_cpu_init() < 0)
+		rte_panic("Cannot detect lcores\n");
+
 	fctret = eal_parse_args(argc, argv);
 	if (fctret < 0)
 		exit(1);
@@ -849,9 +854,6 @@ rte_eal_init(int argc, char **argv)
 
 	rte_config_init();
 	
-	if (rte_eal_cpu_init() < 0)
-		rte_panic("Cannot detect lcores\n");
-
 	if (rte_eal_memory_init() < 0)
 		rte_panic("Cannot init memory\n");
 
diff --git a/lib/librte_eal/linuxapp/eal/eal_lcore.c b/lib/librte_eal/linuxapp/eal/eal_lcore.c
index 7487f34..768e333 100644
--- a/lib/librte_eal/linuxapp/eal/eal_lcore.c
+++ b/lib/librte_eal/linuxapp/eal/eal_lcore.c
@@ -152,15 +152,19 @@ rte_eal_cpu_init(void)
 	unsigned lcore_id;
 	unsigned count = 0;
 
-	/* disable lcores that were not detected */
-	RTE_LCORE_FOREACH(lcore_id) {
-
+	/*
+	 * Parse the maximum set of logical cores, detect the subset of running
+	 * ones and enable them by default.
+	 */
+	for (lcore_id = 0; lcore_id < RTE_MAX_LCORE; lcore_id++) {
 		lcore_config[lcore_id].detected = cpu_detected(lcore_id);
 		if (lcore_config[lcore_id].detected == 0) {
 			RTE_LOG(DEBUG, EAL, "Skip lcore %u (not detected)\n", lcore_id);
 			config->lcore_role[lcore_id] = ROLE_OFF;
 			continue;
 		}
+		/* By default, each detected core is enabled */
+		config->lcore_role[lcore_id] = ROLE_RTE;
 		lcore_config[lcore_id].core_id = cpu_core_id(lcore_id);
 		lcore_config[lcore_id].socket_id = cpu_socket_id(lcore_id);
 		if (lcore_config[lcore_id].socket_id >= RTE_MAX_NUMA_NODES)
@@ -177,7 +181,7 @@ rte_eal_cpu_init(void)
 				lcore_config[lcore_id].socket_id);
 		count ++;
 	}
-
+	/* Set the count of enabled logical cores of the EAL configuration */
 	config->lcore_count = count;
 
 	return 0;
-- 
1.7.10.4