[RFC PATCH 3/3] eal: allow automatic mapping of high lcore ids

[Bruce Richardson <bruce.richardson@intel.com>]

To use cores with IDs greater than RTE_MAX_LCORE the user must provide a
mapping of those higher core numbers to ids within the 0 - RTE_MAX_LCORE
range. This can be awkward to do manually when more than a few lcores
are involved, so instead we can provide an extra option to EAL to do
this manually.

This patch therefore introduces the "map-lcore-ids" flag, which
automatically maps all provided lcore numbers to start at zero.

Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
---
 drivers/event/dlb2/pf/base/dlb2_resource.c |  2 +-
 lib/eal/common/eal_common_options.c        | 32 ++++++++++++++--------
 lib/eal/common/eal_options.h               |  2 ++
 lib/eal/include/rte_eal.h                  |  2 +-
 4 files changed, 25 insertions(+), 13 deletions(-)

diff --git a/drivers/event/dlb2/pf/base/dlb2_resource.c b/drivers/event/dlb2/pf/base/dlb2_resource.c
index c4bc248afc..541a16db24 100644
--- a/drivers/event/dlb2/pf/base/dlb2_resource.c
+++ b/drivers/event/dlb2/pf/base/dlb2_resource.c
@@ -931,7 +931,7 @@ dlb2_resource_probe(struct dlb2_hw *hw, const void *probe_args)
 	cpu = rte_get_next_lcore(-1, 1, 0);
 	hw->num_prod_cores = 0;
 	if (mask) {
-		int n = rte_eal_parse_coremask(mask, hw->prod_core_list);
+		int n = rte_eal_parse_coremask(mask, hw->prod_core_list, true);
 		if (n <= 0) {
 			DLB2_HW_ERR(hw, ": Invalid producer coremask=%s\n", mask);
 			return -1;
diff --git a/lib/eal/common/eal_common_options.c b/lib/eal/common/eal_common_options.c
index 807ba760ce..107b9eaad5 100644
--- a/lib/eal/common/eal_common_options.c
+++ b/lib/eal/common/eal_common_options.c
@@ -106,6 +106,7 @@ eal_long_options[] = {
 	{OPT_NO_TELEMETRY,      0, NULL, OPT_NO_TELEMETRY_NUM     },
 	{OPT_FORCE_MAX_SIMD_BITWIDTH, 1, NULL, OPT_FORCE_MAX_SIMD_BITWIDTH_NUM},
 	{OPT_HUGE_WORKER_STACK, 2, NULL, OPT_HUGE_WORKER_STACK_NUM     },
+	{OPT_MAP_LCORE_IDS,     0, NULL, OPT_MAP_LCORE_IDS_NUM    },
 
 	{0,                     0, NULL, 0                        }
 };
@@ -152,6 +153,7 @@ TAILQ_HEAD_INITIALIZER(devopt_list);
 static int main_lcore_parsed;
 static int mem_parsed;
 static struct lcore_options {
+	bool map_lcore_ids;
 	const char *core_mask_opt;
 	const char *core_list_opt;
 	const char *core_map_opt;
@@ -723,13 +725,14 @@ check_core_list(int *lcores, unsigned int count)
 	if (len > 0)
 		lcorestr[len - 1] = 0;
 	EAL_LOG(ERR, "To use high physical core ids, "
-		"please use --lcores to map them to lcore ids below RTE_MAX_LCORE, "
+		"please use --map-lcore-ids flag to map core ids automatically, "
+		"or use --lcores to map them manually to lcore ids below RTE_MAX_LCORE, "
 		"e.g. --lcores %s", lcorestr);
 	return -1;
 }
 
 int
-rte_eal_parse_coremask(const char *coremask, int *cores)
+rte_eal_parse_coremask(const char *coremask, int *cores, bool no_check)
 {
 	const char *coremask_orig = coremask;
 	unsigned int count = 0;
@@ -784,7 +787,7 @@ rte_eal_parse_coremask(const char *coremask, int *cores)
 		return -1;
 	}
 
-	if (check_core_list(cores, count) != 0)
+	if (!no_check && check_core_list(cores, count) != 0)
 		return -1;
 
 	return count;
@@ -869,7 +872,7 @@ eal_parse_service_corelist(const char *corelist)
 }
 
 static int
-eal_parse_corelist(const char *corelist, int *cores)
+eal_parse_corelist(const char *corelist, int *cores, bool no_check)
 {
 	unsigned int count = 0, i;
 	char *end = NULL;
@@ -932,7 +935,7 @@ eal_parse_corelist(const char *corelist, int *cores)
 		return -1;
 	}
 
-	if (check_core_list(cores, count))
+	if (!no_check && check_core_list(cores, count))
 		return -1;
 
 	return count;
@@ -1767,6 +1770,9 @@ eal_parse_common_option(int opt, const char *optarg,
 			return -1;
 		}
 		break;
+	case OPT_MAP_LCORE_IDS_NUM:
+		lcore_options.map_lcore_ids = true;
+		break;
 
 	/* don't know what to do, leave this to caller */
 	default:
@@ -1866,10 +1872,11 @@ eal_adjust_config(struct internal_config *internal_cfg)
 
 
 	if (lcore_options.core_mask_opt || lcore_options.core_list_opt) {
-		int lcore_indexes[RTE_MAX_LCORE];
+		bool map_ids = lcore_options.map_lcore_ids;
+		int idxs[RTE_MAX_LCORE];
 		int nb_indexes = lcore_options.core_list_opt ?
-				eal_parse_corelist(lcore_options.core_list_opt, lcore_indexes) :
-				rte_eal_parse_coremask(lcore_options.core_mask_opt, lcore_indexes);
+				eal_parse_corelist(lcore_options.core_list_opt, idxs, map_ids) :
+				rte_eal_parse_coremask(lcore_options.core_mask_opt, idxs, map_ids);
 
 		if (nb_indexes < 0)
 			return -1;
@@ -1877,13 +1884,16 @@ eal_adjust_config(struct internal_config *internal_cfg)
 		char *core_map_opt = malloc(RTE_MAX_LCORE * 10);
 		size_t core_map_len = 0;
 		for (i = 0; i < nb_indexes; i++) {
-			if (!eal_cpu_detected(lcore_indexes[i])) {
-				EAL_LOG(ERR, "core %d not present", lcore_indexes[i]);
+			if (!eal_cpu_detected(idxs[i])) {
+				EAL_LOG(ERR, "core %d not present", idxs[i]);
 				return -1;
 			}
 			int n = snprintf(core_map_opt + core_map_len,
 					(RTE_MAX_LCORE * 10) - core_map_len,
-					"%s%d", i == 0 ? "" : ",", lcore_indexes[i]);
+					"%s%d@%d",
+					i == 0 ? "" : ",",
+					map_ids ? i: idxs[i],
+					idxs[i]);
 			if (n < 0 || (size_t)n >= (RTE_MAX_LCORE * 10) - core_map_len) {
 				EAL_LOG(ERR, "core map string too long");
 				return -1;
diff --git a/lib/eal/common/eal_options.h b/lib/eal/common/eal_options.h
index 95fb4f6108..384c2d016e 100644
--- a/lib/eal/common/eal_options.h
+++ b/lib/eal/common/eal_options.h
@@ -93,6 +93,8 @@ enum {
 	OPT_FORCE_MAX_SIMD_BITWIDTH_NUM,
 #define OPT_HUGE_WORKER_STACK  "huge-worker-stack"
 	OPT_HUGE_WORKER_STACK_NUM,
+#define OPT_MAP_LCORE_IDS  "map-lcore-ids"
+	OPT_MAP_LCORE_IDS_NUM,
 
 	OPT_LONG_MAX_NUM
 };
diff --git a/lib/eal/include/rte_eal.h b/lib/eal/include/rte_eal.h
index c826e143f1..a53fb29c45 100644
--- a/lib/eal/include/rte_eal.h
+++ b/lib/eal/include/rte_eal.h
@@ -508,7 +508,7 @@ rte_eal_get_runtime_dir(void);
  */
 __rte_internal
 int
-rte_eal_parse_coremask(const char *coremask, int *cores);
+rte_eal_parse_coremask(const char *coremask, int *cores, bool nocheck);
 
 #ifdef __cplusplus
 }
-- 
2.43.0