From: Yury Norov <yury.norov@gmail.com>
To: linux-kernel@vger.kernel.org
Cc: Yury Norov <yury.norov@gmail.com>,
Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
Rasmus Villemoes <linux@rasmusvillemoes.dk>,
Andrew Morton <akpm@linux-foundation.org>,
Stephen Rothwell <sfr@canb.auug.org.au>,
Peter Zijlstra <peterz@infradead.org>,
Thomas Gleixner <tglx@linutronix.de>,
"Paul E . McKenney" <paulmck@kernel.org>,
Vlastimil Babka <vbabka@suse.cz>,
Dmitry Vyukov <dvyukov@google.com>,
Valentin Schneider <vschneid@redhat.com>,
Sander Vanheule <sander@svanheule.net>,
Alexey Klimov <klimov.linux@gmail.com>,
Eric Biggers <ebiggers@google.com>
Subject: [PATCH v2 2/5] smp: add set_nr_cpu_ids()
Date: Mon, 5 Sep 2022 16:08:17 -0700 [thread overview]
Message-ID: <20220905230820.3295223-3-yury.norov@gmail.com> (raw)
In-Reply-To: <20220905230820.3295223-1-yury.norov@gmail.com>
In preparation to support compile-time nr_cpu_ids, add a setter for
the variable.
This is a no-op for all arches.
Signed-off-by: Yury Norov <yury.norov@gmail.com>
---
arch/loongarch/kernel/setup.c | 2 +-
arch/mips/kernel/setup.c | 2 +-
arch/x86/kernel/smpboot.c | 4 ++--
arch/x86/xen/smp_pv.c | 2 +-
include/linux/cpumask.h | 5 +++++
kernel/smp.c | 4 ++--
6 files changed, 12 insertions(+), 7 deletions(-)
diff --git a/arch/loongarch/kernel/setup.c b/arch/loongarch/kernel/setup.c
index 8f5c2f9a1a83..18a81edd3ac5 100644
--- a/arch/loongarch/kernel/setup.c
+++ b/arch/loongarch/kernel/setup.c
@@ -346,7 +346,7 @@ static void __init prefill_possible_map(void)
for (; i < NR_CPUS; i++)
set_cpu_possible(i, false);
- nr_cpu_ids = possible;
+ set_nr_cpu_ids(possible);
}
#endif
diff --git a/arch/mips/kernel/setup.c b/arch/mips/kernel/setup.c
index 2ca156a5b231..e8a0759cb4d0 100644
--- a/arch/mips/kernel/setup.c
+++ b/arch/mips/kernel/setup.c
@@ -750,7 +750,7 @@ static void __init prefill_possible_map(void)
for (; i < NR_CPUS; i++)
set_cpu_possible(i, false);
- nr_cpu_ids = possible;
+ set_nr_cpu_ids(possible);
}
#else
static inline void prefill_possible_map(void) {}
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index f24227bc3220..3f3ea0287f69 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -1316,7 +1316,7 @@ static void __init smp_sanity_check(void)
nr++;
}
- nr_cpu_ids = 8;
+ set_nr_cpu_ids(8);
}
#endif
@@ -1569,7 +1569,7 @@ __init void prefill_possible_map(void)
possible = i;
}
- nr_cpu_ids = possible;
+ set_nr_cpu_ids(possible);
pr_info("Allowing %d CPUs, %d hotplug CPUs\n",
possible, max_t(int, possible - num_processors, 0));
diff --git a/arch/x86/xen/smp_pv.c b/arch/x86/xen/smp_pv.c
index ba7af2eca755..480be82e9b7b 100644
--- a/arch/x86/xen/smp_pv.c
+++ b/arch/x86/xen/smp_pv.c
@@ -179,7 +179,7 @@ static void __init _get_smp_config(unsigned int early)
* hypercall to expand the max number of VCPUs an already
* running guest has. So cap it up to X. */
if (subtract)
- nr_cpu_ids = nr_cpu_ids - subtract;
+ set_nr_cpu_ids(nr_cpu_ids - subtract);
#endif
}
diff --git a/include/linux/cpumask.h b/include/linux/cpumask.h
index bd047864c7ac..0588bfe350d4 100644
--- a/include/linux/cpumask.h
+++ b/include/linux/cpumask.h
@@ -39,6 +39,11 @@ typedef struct cpumask { DECLARE_BITMAP(bits, NR_CPUS); } cpumask_t;
#define nr_cpu_ids 1U
#else
extern unsigned int nr_cpu_ids;
+
+static inline void set_nr_cpu_ids(unsigned int nr)
+{
+ nr_cpu_ids = nr;
+}
#endif
#ifdef CONFIG_CPUMASK_OFFSTACK
diff --git a/kernel/smp.c b/kernel/smp.c
index e971c9626a1b..150310a0947a 100644
--- a/kernel/smp.c
+++ b/kernel/smp.c
@@ -1070,7 +1070,7 @@ static int __init nrcpus(char *str)
int nr_cpus;
if (get_option(&str, &nr_cpus) && nr_cpus > 0 && nr_cpus < nr_cpu_ids)
- nr_cpu_ids = nr_cpus;
+ set_nr_cpu_ids(nr_cpus);
return 0;
}
@@ -1097,7 +1097,7 @@ EXPORT_SYMBOL(nr_cpu_ids);
/* An arch may set nr_cpu_ids earlier if needed, so this would be redundant */
void __init setup_nr_cpu_ids(void)
{
- nr_cpu_ids = find_last_bit(cpumask_bits(cpu_possible_mask),NR_CPUS) + 1;
+ set_nr_cpu_ids(find_last_bit(cpumask_bits(cpu_possible_mask), NR_CPUS) + 1);
}
/* Called by boot processor to activate the rest. */
--
2.34.1
next prev parent reply other threads:[~2022-09-05 23:08 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-09-05 23:08 [PATCH v2 0/5] cpumask: cleanup nr_cpu_ids vs nr_cpumask_bits mess Yury Norov
2022-09-05 23:08 ` [PATCH v2 1/5] smp: don't declare nr_cpu_ids if NR_CPUS == 1 Yury Norov
2022-09-06 8:53 ` Peter Zijlstra
2022-09-06 14:06 ` Yury Norov
2022-09-06 14:36 ` Peter Zijlstra
2022-09-06 15:01 ` Andy Shevchenko
2022-09-06 17:53 ` Peter Zijlstra
2022-09-06 15:07 ` Yury Norov
2022-09-07 8:02 ` David Laight
2022-09-05 23:08 ` Yury Norov [this message]
2022-09-05 23:08 ` [PATCH v2 3/5] lib/cpumask: delete misleading comment Yury Norov
2022-09-05 23:08 ` [PATCH v2 4/5] lib/cpumask: deprecate nr_cpumask_bits Yury Norov
2022-09-05 23:08 ` [PATCH v2 5/5] lib/cpumask: add FORCE_NR_CPUS config option Yury Norov
2022-10-18 8:21 ` Geert Uytterhoeven
2022-10-18 13:15 ` Geert Uytterhoeven
2022-10-18 13:41 ` Andreas Schwab
2022-10-18 13:50 ` Geert Uytterhoeven
2022-10-18 14:35 ` Yury Norov
2022-10-18 14:44 ` Andy Shevchenko
2022-10-18 14:59 ` Yury Norov
2022-10-18 15:15 ` Geert Uytterhoeven
2022-10-18 16:16 ` Yury Norov
2022-10-19 6:58 ` Geert Uytterhoeven
2022-09-06 8:55 ` [PATCH v2 0/5] cpumask: cleanup nr_cpu_ids vs nr_cpumask_bits mess Peter Zijlstra
2022-09-06 12:06 ` Valentin Schneider
2022-09-06 14:38 ` Peter Zijlstra
2022-09-06 15:45 ` Valentin Schneider
2022-09-06 16:26 ` Yury Norov
2022-09-06 14:48 ` Yury Norov
2022-09-06 14:35 ` Yury Norov
2022-09-15 14:45 ` Yury Norov
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