[dpdk-dev] [PATCH v5 3/7] service cores: coremask parsing

[Harry van Haaren <harry.van.haaren@intel.com>]

Add logic for parsing a coremask from EAL, which allows
the application to be unaware of the cores being taken from
its coremask.

Signed-off-by: Harry van Haaren <harry.van.haaren@intel.com>

Acked-by: Jerin Jacob <jerin.jacob@caviumnetworks.com>

---

v4:
- Add --help print output (Jerin)
- Fixed coremask parsing to ensure master core is ROLE_RTE (Jerin)
- Improve coremask parsing error handling, master lcore and service coremask
  overlap is failed, informing user that the core cannot be used for the
  purpose A as it is already in use for B (A or B being service/master)

v2:
- Remove printf() (Jerin)
- Remove commented code (Jerin)
- simplified core tracking, no requirement on
  #include rte_service in EAL parsing anymore.

wip: fix master lcore handling in EAL
---
 lib/librte_eal/common/eal_common_options.c | 91 +++++++++++++++++++++++++++++-
 1 file changed, 90 insertions(+), 1 deletion(-)

diff --git a/lib/librte_eal/common/eal_common_options.c b/lib/librte_eal/common/eal_common_options.c
index 075b0ea..00265d6 100644
--- a/lib/librte_eal/common/eal_common_options.c
+++ b/lib/librte_eal/common/eal_common_options.c
@@ -61,6 +61,7 @@ const char
 eal_short_options[] =
 	"b:" /* pci-blacklist */
 	"c:" /* coremask */
+	"s:" /* service coremask */
 	"d:" /* driver */
 	"h"  /* help */
 	"l:" /* corelist */
@@ -267,6 +268,77 @@ static int xdigit2val(unsigned char c)
 }
 
 static int
+eal_parse_service_coremask(const char *coremask)
+{
+	struct rte_config *cfg = rte_eal_get_configuration();
+	int i, j, idx = 0;
+	unsigned int count = 0;
+	char c;
+	int val;
+
+	if (coremask == NULL)
+		return -1;
+	/* Remove all blank characters ahead and after .
+	 * Remove 0x/0X if exists.
+	 */
+	while (isblank(*coremask))
+		coremask++;
+	if (coremask[0] == '0' && ((coremask[1] == 'x')
+		|| (coremask[1] == 'X')))
+		coremask += 2;
+	i = strlen(coremask);
+	while ((i > 0) && isblank(coremask[i - 1]))
+		i--;
+
+	if (i == 0)
+		return -1;
+
+	for (i = i - 1; i >= 0 && idx < RTE_MAX_LCORE; i--) {
+		c = coremask[i];
+		if (isxdigit(c) == 0) {
+			/* invalid characters */
+			return -1;
+		}
+		val = xdigit2val(c);
+		for (j = 0; j < BITS_PER_HEX && idx < RTE_MAX_LCORE;
+				j++, idx++) {
+			if ((1 << j) & val) {
+				/* handle master lcore already parsed */
+				uint32_t lcore = idx;
+				if (master_lcore_parsed &&
+						cfg->master_lcore == lcore) {
+					RTE_LOG(ERR, EAL,
+						"Error: lcore %u is master lcore, cannot use as service core\n",
+						idx);
+					return -1;
+				}
+
+				if (!lcore_config[idx].detected) {
+					RTE_LOG(ERR, EAL,
+						"lcore %u unavailable\n", idx);
+					return -1;
+				}
+				lcore_config[idx].core_role = ROLE_SERVICE;
+				count++;
+			}
+		}
+	}
+
+	for (; i >= 0; i--)
+		if (coremask[i] != '0')
+			return -1;
+
+	for (; idx < RTE_MAX_LCORE; idx++)
+		lcore_config[idx].core_index = -1;
+
+	if (count == 0)
+		return -1;
+
+	cfg->service_lcore_count = count;
+	return 0;
+}
+
+static int
 eal_parse_coremask(const char *coremask)
 {
 	struct rte_config *cfg = rte_eal_get_configuration();
@@ -409,6 +481,13 @@ eal_parse_master_lcore(const char *arg)
 	if (cfg->master_lcore >= RTE_MAX_LCORE)
 		return -1;
 	master_lcore_parsed = 1;
+
+	/* ensure master core is not used as service core */
+	if (lcore_config[cfg->master_lcore].core_role == ROLE_SERVICE) {
+		RTE_LOG(ERR, EAL, "Error: Master lcore is used as a service core.\n");
+		return -1;
+	}
+
 	return 0;
 }
 
@@ -826,6 +905,13 @@ eal_parse_common_option(int opt, const char *optarg,
 		}
 		core_parsed = 1;
 		break;
+	/* service coremask */
+	case 's':
+		if (eal_parse_service_coremask(optarg) < 0) {
+			RTE_LOG(ERR, EAL, "invalid service coremask\n");
+			return -1;
+		}
+		break;
 	/* size of memory */
 	case 'm':
 		conf->memory = atoi(optarg);
@@ -978,8 +1064,10 @@ eal_adjust_config(struct internal_config *internal_cfg)
 		internal_config.process_type = eal_proc_type_detect();
 
 	/* default master lcore is the first one */
-	if (!master_lcore_parsed)
+	if (!master_lcore_parsed) {
 		cfg->master_lcore = rte_get_next_lcore(-1, 0, 0);
+		lcore_config[cfg->master_lcore].core_role = ROLE_RTE;
+	}
 
 	/* if no memory amounts were requested, this will result in 0 and
 	 * will be overridden later, right after eal_hugepage_info_init() */
@@ -1045,6 +1133,7 @@ eal_common_usage(void)
 	       "                      ',' is used for single number separator.\n"
 	       "                      '( )' can be omitted for single element group,\n"
 	       "                      '@' can be omitted if cpus and lcores have the same value\n"
+	       "  -s SERVICE COREMASK Hexadecimal bitmask of cores to be used as service cores\n"
 	       "  --"OPT_MASTER_LCORE" ID   Core ID that is used as master\n"
 	       "  -n CHANNELS         Number of memory channels\n"
 	       "  -m MB               Memory to allocate (see also --"OPT_SOCKET_MEM")\n"
-- 
2.7.4