linux-kernel - [PATCH v2] x86: Put the num_processors++ code in a more suitable position

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Date:   Wed, 7 Sep 2016 10:21:33 +0800
From:   Dou Liyang <douly.fnst@...fujitsu.com>
To:     <linux-kernel@...r.kernel.org>
CC:     <x86@...nel.org>, <tglx@...utronix.de>, <mingo@...hat.com>,
        <hpa@...or.com>, <rientjes@...gle.com>,
        Dou Liyang <douly.fnst@...fujitsu.com>
Subject: [PATCH v2] x86: Put the num_processors++ code in a more suitable position

This code is just for correctness.

If checking the topology package map of apicid and cpu is failure,
it will stop generating the processor info for that apicid and the
disabled_cpus will plus one. However, the num-processors has already
been added one above. That may cause the number of processors incorrect.

Just put the num_processors++ code in the more suitable position.
it makes sure that the num-processors will not conflict with the
disabled_cpus.

Signed-off-by: Dou Liyang <douly.fnst@...fujitsu.com>
Acked-by: David Rientjes <rientjes@...gle.com>
---
 arch/x86/kernel/apic/apic.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index 50c95af..f3e9b2d 100644
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -2093,7 +2093,6 @@ int generic_processor_info(int apicid, int version)
 		return -EINVAL;
 	}

-	num_processors++;
 	if (apicid == boot_cpu_physical_apicid) {
 		/*
 		 * x86_bios_cpu_apicid is required to have processors listed
@@ -2116,10 +2115,13 @@ int generic_processor_info(int apicid, int version)

 		pr_warning("APIC: Package limit reached. Processor %d/0x%x ignored.\n",
 			   thiscpu, apicid);
+
 		disabled_cpus++;
 		return -ENOSPC;
 	}

+	num_processors++;
+
 	/*
 	 * Validate version
 	 */
-- 
2.5.5