[dpdk-dev] [PATCH] eal/bsd: query the cpu count only once

[dpdk-dev] [PATCH] eal/bsd: query the cpu count only once

[Bruce Richardson]

Rather than querying the number of CPUs on the system multiple times, and
printing out the number each time, just query the value from sysctl once
and store it for future reuse.

Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
---
 lib/librte_eal/bsdapp/eal/eal_lcore.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/lib/librte_eal/bsdapp/eal/eal_lcore.c b/lib/librte_eal/bsdapp/eal/eal_lcore.c
index b8bfafde0..bc584dd53 100644
--- a/lib/librte_eal/bsdapp/eal/eal_lcore.c
+++ b/lib/librte_eal/bsdapp/eal/eal_lcore.c
@@ -53,12 +53,14 @@ eal_cpu_core_id(__rte_unused unsigned lcore_id)
 static int
 eal_get_ncpus(void)
 {
+	static int ncpu = -1;
 	int mib[2] = {CTL_HW, HW_NCPU};
-	int ncpu;
 	size_t len = sizeof(ncpu);
 
-	sysctl(mib, 2, &ncpu, &len, NULL, 0);
-	RTE_LOG(INFO, EAL, "Sysctl reports %d cpus\n", ncpu);
+	if (ncpu < 0) {
+		sysctl(mib, 2, &ncpu, &len, NULL, 0);
+		RTE_LOG(INFO, EAL, "Sysctl reports %d cpus\n", ncpu);
+	}
 	return ncpu;
 }
 
-- 
2.11.0

Re: [dpdk-dev] [PATCH] eal/bsd: query the cpu count only once

[Thomas Monjalon]

2017-03-23 15:09, Bruce Richardson:
> Rather than querying the number of CPUs on the system multiple times, and
> printing out the number each time, just query the value from sysctl once
> and store it for future reuse.
> 
> Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>

Applied, thanks