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From: Brad Smith <brad@comstyle.com>
To: git@vger.kernel.org
Subject: [PATCH] thread-utils.c: detect online CPU count on OpenBSD / NetBSD
Date: Fri, 9 May 2025 02:13:13 -0400	[thread overview]
Message-ID: <aB2c-W0V83aVDpZr@humpty.home.comstyle.com> (raw)

OpenBSD / NetBSD use HW_NCPUONLINE to detect the online CPU
count. OpenBSD ships with SMT disabled on X86 systems so
HW_NCPU would provide double the number of CPUs as opposed
to the proper online count.

Signed-off-by: Brad Smith <brad@comstyle.com>
---
 thread-utils.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/thread-utils.c b/thread-utils.c
index 1f89ffab4c..374890e6b0 100644
--- a/thread-utils.c
+++ b/thread-utils.c
@@ -46,11 +46,11 @@ int online_cpus(void)
 	mib[0] = CTL_HW;
 #  ifdef HW_AVAILCPU
 	mib[1] = HW_AVAILCPU;
-	len = sizeof(cpucount);
-	if (!sysctl(mib, 2, &cpucount, &len, NULL, 0))
-		return cpucount;
-#  endif /* HW_AVAILCPU */
+#  elif defined(HW_NCPUONLINE)
+	mib[1] = HW_NCPUONLINE;
+#  else
 	mib[1] = HW_NCPU;
+#  endif /* HW_AVAILCPU */
 	len = sizeof(cpucount);
 	if (!sysctl(mib, 2, &cpucount, &len, NULL, 0))
 		return cpucount;
-- 
2.49.0


             reply	other threads:[~2025-05-09  6:13 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-05-09  6:13 Brad Smith [this message]
2025-05-09  8:36 ` [PATCH] thread-utils.c: detect online CPU count on OpenBSD / NetBSD Patrick Steinhardt
2025-05-31 20:18 ` Brad Smith
2025-06-01  2:14 ` Collin Funk

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