From nobody Mon Feb 9 01:45:48 2026 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id A0B95142902 for ; Thu, 21 Mar 2024 16:53:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711039982; cv=none; b=sG8kEELGCpiVncQOovyG4hIIKVGHFGCNJ9vMlPBeanfKamI8+/n2vb1W0UymqhtG8cm8DajkE1t9mEw47LaadVBlwJfTFl+MGV8/vdyQ0UZ1EDlU7jbODluX+BPXQaeS8YHSBsdFzFnly86+UI4RHKXB32M47nuMW925I8sQNgY= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711039982; c=relaxed/simple; bh=T88a3dvbF49aC2qKu/i0t9netSqmUU/dw4wLFshprXQ=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=i82uCTM7NP/JZjejSdwRExjOAeOZ53oxRX0SYRLua3DxEA/Svd9t9RMYtoAd8gH6baxUVHq6m+RkRqMZpYFLF34Qh7Dp4sKr/e6YePTeDGaa0SgXkXtNWVAPb+WnXkPv5jkrZyVC8QwzXmYRK437EAcNkcvV/iu8rBLlFpfLgc0= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 8BECF1007; Thu, 21 Mar 2024 09:53:34 -0700 (PDT) Received: from merodach.members.linode.com (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 4CB9B3F67D; Thu, 21 Mar 2024 09:52:57 -0700 (PDT) From: James Morse To: x86@kernel.org, linux-kernel@vger.kernel.org Cc: Fenghua Yu , Reinette Chatre , Thomas Gleixner , Ingo Molnar , Borislav Petkov , H Peter Anvin , Babu Moger , James Morse , shameerali.kolothum.thodi@huawei.com, D Scott Phillips OS , carl@os.amperecomputing.com, lcherian@marvell.com, bobo.shaobowang@huawei.com, tan.shaopeng@fujitsu.com, baolin.wang@linux.alibaba.com, Jamie Iles , Xin Hao , peternewman@google.com, dfustini@baylibre.com, amitsinght@marvell.com, David Hildenbrand , Rex Nie , Dave Martin Subject: [PATCH v1 28/31] x86/resctrl: Drop __init/__exit on assorted symbols Date: Thu, 21 Mar 2024 16:51:03 +0000 Message-Id: <20240321165106.31602-29-james.morse@arm.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20240321165106.31602-1-james.morse@arm.com> References: <20240321165106.31602-1-james.morse@arm.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Because ARM's MPAM controls are probed using MMIO, resctrl can't be initialised until enough CPUs are online to have determined the system-wide supported num_closid. Arm64 also supports 'late onlined secondaries', where only a subset of CPUs are online during boot. These two combine to mean the MPAM driver may not be able to initialise resctrl until user-space has brought 'enough' CPUs online. To allow MPAM to initialise resctrl after __init text has been free'd, remove all the __init markings from resctrl. The existing __exit markings cause these functions to be removed by the linker as it has never been possible to build resctrl as a module. MPAM has an error interrupt which causes the driver to reset and disable itself. Remove the __exit markings to allow the MPAM driver to tear down resctrl when an error occurs. Signed-off-by: James Morse --- If 'late onlined secondaries' is an alien concept, I can add a worked example to the commit message: If a system has two L3 caches, but during boot only CPU-0 is online, then no CPU is able to probe the features of the second L3 cache. It's not until user-space brings other CPUs online that the MPAM driver can finally get a glimpse of all the hardware to determine what properties the system has. --- arch/x86/kernel/cpu/resctrl/internal.h | 2 +- arch/x86/kernel/cpu/resctrl/monitor.c | 4 ++-- arch/x86/kernel/cpu/resctrl/rdtgroup.c | 8 ++++---- include/linux/resctrl.h | 4 ++-- 4 files changed, 9 insertions(+), 9 deletions(-) diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/r= esctrl/internal.h index 3a3962736061..56218193a8ba 100644 --- a/arch/x86/kernel/cpu/resctrl/internal.h +++ b/arch/x86/kernel/cpu/resctrl/internal.h @@ -457,7 +457,7 @@ void closid_free(int closid); int alloc_rmid(u32 closid); void free_rmid(u32 closid, u32 rmid); int rdt_get_mon_l3_config(struct rdt_resource *r); -void __exit resctrl_mon_resource_exit(void); +void resctrl_mon_resource_exit(void); bool rdt_cpu_has(int flag); void mon_event_count(void *info); int rdtgroup_mondata_show(struct seq_file *m, void *arg); diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/re= sctrl/monitor.c index 8b316d9acc3b..7e6fca138cb7 100644 --- a/arch/x86/kernel/cpu/resctrl/monitor.c +++ b/arch/x86/kernel/cpu/resctrl/monitor.c @@ -954,7 +954,7 @@ static int dom_data_init(struct rdt_resource *r) return err; } =20 -static void __exit dom_data_exit(struct rdt_resource *r) +static void dom_data_exit(struct rdt_resource *r) { if (!r->mon_capable) return; @@ -1076,7 +1076,7 @@ int __init rdt_get_mon_l3_config(struct rdt_resource = *r) return 0; } =20 -void __exit resctrl_mon_resource_exit(void) +void resctrl_mon_resource_exit(void) { struct rdt_resource *r =3D resctrl_arch_get_resource(RDT_RESOURCE_L3); =20 diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/r= esctrl/rdtgroup.c index 218aebd6387f..1425a33d201d 100644 --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c @@ -2069,7 +2069,7 @@ static struct rftype *rdtgroup_get_rftype_by_name(con= st char *name) return NULL; } =20 -static void __init thread_throttle_mode_init(void) +static void thread_throttle_mode_init(void) { struct rdt_resource *r =3D resctrl_arch_get_resource(RDT_RESOURCE_MBA); struct rftype *rft; @@ -3997,7 +3997,7 @@ static void rdtgroup_destroy_root(void) rdtgroup_default.kn =3D NULL; } =20 -static void __init rdtgroup_setup_default(void) +static void rdtgroup_setup_default(void) { mutex_lock(&rdtgroup_mutex); =20 @@ -4190,7 +4190,7 @@ void resctrl_offline_cpu(unsigned int cpu) * * Return: 0 on success or -errno */ -int __init resctrl_init(void) +int resctrl_init(void) { int ret =3D 0; =20 @@ -4244,7 +4244,7 @@ int __init resctrl_init(void) return ret; } =20 -void __exit resctrl_exit(void) +void resctrl_exit(void) { debugfs_remove_recursive(debugfs_resctrl); unregister_filesystem(&rdt_fs_type); diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h index f463fb949677..5da55e58f229 100644 --- a/include/linux/resctrl.h +++ b/include/linux/resctrl.h @@ -393,7 +393,7 @@ void resctrl_arch_reset_rmid_all(struct rdt_resource *r= , struct rdt_domain *d); extern unsigned int resctrl_rmid_realloc_threshold; extern unsigned int resctrl_rmid_realloc_limit; =20 -int __init resctrl_init(void); -void __exit resctrl_exit(void); +int resctrl_init(void); +void resctrl_exit(void); =20 #endif /* _RESCTRL_H */ --=20 2.39.2