From nobody Sat May 18 05:34:57 2024 Received: from mail.loongson.cn (mail.loongson.cn [114.242.206.163]) by smtp.subspace.kernel.org (Postfix) with ESMTP id D7F5C15D5C1 for ; Thu, 18 Apr 2024 11:05:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=114.242.206.163 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713438340; cv=none; b=WwNBbrATNy45Hw8P0p3Ojk3493K2LmoZnOe0Kj40XIx1oWv687EwyV4seKidplk1vtBaU34L81PYo0DVKnw5BALUwg1T/XD+QNlQNXbUVStF1m7IkvQF3dAAbhwkUlRZb87z6fWBzQIbuMQL1udnjAY1e0GlUiS6at2IyyZztHw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713438340; c=relaxed/simple; bh=lUKbfHT2CeWuRaF2K1IWI2/Tr2D9SeaelyavaVNWbf8=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=E6JSLE7jkaMYt12HCmx8tgMQoq1+dC6m4ywc91dh2F2Yq3hBw2HPVCjMrDx6es53g2z5YcyjlmhaoTyBVkI1X5K1fpznANe0pHokq3pE4UJhfQJyaBUBB2ssxFL9qr4tYEjH+9niysFftf5R90p0AdTz1IkP3ORfGW6AyTqAndo= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=loongson.cn; spf=pass smtp.mailfrom=loongson.cn; arc=none smtp.client-ip=114.242.206.163 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=loongson.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=loongson.cn Received: from loongson.cn (unknown [113.200.148.30]) by gateway (Coremail) with SMTP id _____8Cxbet1_iBmQj0pAA--.27994S3; Thu, 18 Apr 2024 19:05:25 +0800 (CST) Received: from linux.localdomain (unknown [113.200.148.30]) by localhost.localdomain (Coremail) with SMTP id AQAAf8DxuhJx_iBm9g1_AA--.34063S2; Thu, 18 Apr 2024 19:05:21 +0800 (CST) From: Tiezhu Yang To: Huacai Chen , Thomas Gleixner , Arnd Bergmann , Marc Zyngier Cc: loongarch@lists.linux.dev, linux-kernel@vger.kernel.org, loongson-kernel@lists.loongnix.cn Subject: [PATCH v5] LoongArch: Give chance to build under !CONFIG_SMP Date: Thu, 18 Apr 2024 19:05:20 +0800 Message-ID: <20240418110520.16915-1-yangtiezhu@loongson.cn> X-Mailer: git-send-email 2.42.0 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 X-CM-TRANSID: AQAAf8DxuhJx_iBm9g1_AA--.34063S2 X-CM-SenderInfo: p1dqw3xlh2x3gn0dqz5rrqw2lrqou0/ X-Coremail-Antispam: 1Uk129KBj93XoW3Jr4UKFWDJw4kZF13Xw4DZFc_yoW3XrWrpF yqyr4Dtr4rGrn7Aryqy3yrWr15Jr1kG3y2qFy2k3y8GFnrX348Xr4vgFnIqFyUKwsYgFWI vFn3Wa4aqF1UAwcCm3ZEXasCq-sJn29KB7ZKAUJUUUUx529EdanIXcx71UUUUU7KY7ZEXa sCq-sGcSsGvfJ3Ic02F40EFcxC0VAKzVAqx4xG6I80ebIjqfuFe4nvWSU5nxnvy29KBjDU 0xBIdaVrnRJUUUB2b4IE77IF4wAFF20E14v26r1j6r4UM7CY07I20VC2zVCF04k26cxKx2 IYs7xG6rWj6s0DM7CIcVAFz4kK6r1Y6r17M28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48v e4kI8wA2z4x0Y4vE2Ix0cI8IcVAFwI0_JFI_Gr1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI 0_Gr0_Cr1l84ACjcxK6I8E87Iv67AKxVW8Jr0_Cr1UM28EF7xvwVC2z280aVCY1x0267AK xVW8Jr0_Cr1UM2kKe7AKxVWUAVWUtwAS0I0E0xvYzxvE52x082IY62kv0487Mc804VCY07 AIYIkI8VC2zVCFFI0UMc02F40EFcxC0VAKzVAqx4xG6I80ewAv7VC0I7IYx2IY67AKxVWU AVWUtwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFVCjc4AY6r1j6r4UM4x0Y48IcxkI7V AKI48JMxkF7I0En4kS14v26r126r1DMxAIw28IcxkI7VAKI48JMxC20s026xCaFVCjc4AY 6r1j6r4UMxCIbckI1I0E14v26r126r1DMI8I3I0E5I8CrVAFwI0_Jr0_Jr4lx2IqxVCjr7 xvwVAFwI0_JrI_JrWlx4CE17CEb7AF67AKxVWUAVWUtwCIc40Y0x0EwIxGrwCI42IY6xII jxv20xvE14v26r1I6r4UMIIF0xvE2Ix0cI8IcVCY1x0267AKxVWUJVW8JwCI42IY6xAIw2 0EY4v20xvaj40_Jr0_JF4lIxAIcVC2z280aVAFwI0_Jr0_Gr1lIxAIcVC2z280aVCY1x02 67AKxVWUJVW8JbIYCTnIWIevJa73UjIFyTuYvjxUcbAwUUUUU Content-Type: text/plain; charset="utf-8" In the current code, SMP is selected in Kconfig for LoongArch, the users can not unset it, this is reasonable for a multiprocessor machine. But as the help info of config SMP said, if you have a system with only one CPU, say N. On a uniprocessor machine, the kernel will run faster if you say N here. The Loongson-2K0500 is a single-core CPU for applications like industrial control, printing terminals, and BMC (Baseboard Management Controller), there are many development boards, products and solutions on the market, so it is better and necessary to give a chance to build under !CONFIG_SMP for a uniprocessor machine. First of all, do not select SMP for config LOONGARCH in Kconfig to make it possible to unset CONFIG_SMP. Then, do some changes to fix the warnings and errors if CONFIG_SMP is not set. (1) Define get_ipi_irq() only if CONFIG_SMP is set to fix the warning: arch/loongarch/kernel/irq.c:90:19: warning: 'get_ipi_irq' defined but not u= sed [-Wunused-function] (2) Add "#ifdef CONFIG_SMP" in asm/smp.h to fix the warning: ./arch/loongarch/include/asm/smp.h:49:9: warning: "raw_smp_processor_id" re= defined 49 | #define raw_smp_processor_id raw_smp_processor_id | ^~~~~~~~~~~~~~~~~~~~ ./include/linux/smp.h:198:9: note: this is the location of the previous def= inition 198 | #define raw_smp_processor_id() 0 (3) Define machine_shutdown() as empty under !CONFIG_SMP to fix the error: arch/loongarch/kernel/machine_kexec.c: In function 'machine_shutdown': arch/loongarch/kernel/machine_kexec.c:233:25: error: implicit declaration o= f function 'cpu_device_up'; did you mean 'put_device'? [-Wimplicit-function= -declaration] (4) Make config SCHED_SMT depends on SMP to fix many errors such as: kernel/sched/core.c: In function 'sched_core_find': kernel/sched/core.c:310:43: error: 'struct rq' has no member named 'cpu' (5) Define cpu_logical_map(cpu) as 0 under !CONFIG_SMP in asm/smp.h, then include asm/smp.h in asm/acpi.h (because acpi.h is included in linux/irq.h indirectly) to fix many build errors under drivers/irqchip such as: drivers/irqchip/irq-loongson-eiointc.c: In function 'cpu_to_eio_node': drivers/irqchip/irq-loongson-eiointc.c:59:16: error: implicit declaration o= f function 'cpu_logical_map' [-Wimplicit-function-declaration] (6) Do not write per_cpu_offset(0) to PERCPU_BASE_KS when resume because per_cpu_offset(x) is defined as __per_cpu_offset[x]) only under CONFIG_SMP in include/asm-generic/percpu.h, just save the value of PERCPU_BASE_KS when suspend and restore it when resume to fix the error: arch/loongarch/power/suspend.c: In function 'loongarch_common_resume': arch/loongarch/power/suspend.c:47:21: error: implicit declaration of functi= on 'per_cpu_offset' [-Wimplicit-function-declaration] When running the UnixBench tests with "-c 1" single-streamed pass, the improvement in performance is about 9 percent with this patch. By the way, it is helpful to debug and analysis the kernel issue of multi-core system under !CONFIG_SMP. Signed-off-by: Tiezhu Yang --- v5: -- Drop the changes of arch/loongarch/kernel/acpi.c -- Define cpu_logical_map(cpu) as 0 under !CONFIG_SMP -- Squash the changes of suspend.c into one single patch arch/loongarch/Kconfig | 2 +- arch/loongarch/include/asm/acpi.h | 1 + arch/loongarch/include/asm/smp.h | 5 +++++ arch/loongarch/kernel/irq.c | 2 ++ arch/loongarch/kernel/machine_kexec.c | 2 +- arch/loongarch/power/suspend.c | 4 +++- 6 files changed, 13 insertions(+), 3 deletions(-) diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig index a5f300ec6f28..8d892de0b7a8 100644 --- a/arch/loongarch/Kconfig +++ b/arch/loongarch/Kconfig @@ -174,7 +174,6 @@ config LOONGARCH select PCI_QUIRKS select PERF_USE_VMALLOC select RTC_LIB - select SMP select SPARSE_IRQ select SYSCTL_ARCH_UNALIGN_ALLOW select SYSCTL_ARCH_UNALIGN_NO_WARN @@ -420,6 +419,7 @@ config EFI_STUB =20 config SCHED_SMT bool "SMT scheduler support" + depends on SMP default y help Improves scheduler's performance when there are multiple diff --git a/arch/loongarch/include/asm/acpi.h b/arch/loongarch/include/asm= /acpi.h index 49e29b29996f..313f66f7913a 100644 --- a/arch/loongarch/include/asm/acpi.h +++ b/arch/loongarch/include/asm/acpi.h @@ -8,6 +8,7 @@ #ifndef _ASM_LOONGARCH_ACPI_H #define _ASM_LOONGARCH_ACPI_H =20 +#include #include =20 #ifdef CONFIG_ACPI diff --git a/arch/loongarch/include/asm/smp.h b/arch/loongarch/include/asm/= smp.h index f81e5f01d619..8190b093a687 100644 --- a/arch/loongarch/include/asm/smp.h +++ b/arch/loongarch/include/asm/smp.h @@ -6,6 +6,7 @@ #ifndef __ASM_SMP_H #define __ASM_SMP_H =20 +#ifdef CONFIG_SMP #include #include #include @@ -101,4 +102,8 @@ static inline void __cpu_die(unsigned int cpu) } #endif =20 +#else /* !CONFIG_SMP */ +#define cpu_logical_map(cpu) 0 +#endif /* CONFIG_SMP */ + #endif /* __ASM_SMP_H */ diff --git a/arch/loongarch/kernel/irq.c b/arch/loongarch/kernel/irq.c index 883e5066ae44..e791fa275ec5 100644 --- a/arch/loongarch/kernel/irq.c +++ b/arch/loongarch/kernel/irq.c @@ -87,6 +87,7 @@ static void __init init_vec_parent_group(void) acpi_table_parse(ACPI_SIG_MCFG, early_pci_mcfg_parse); } =20 +#ifdef CONFIG_SMP static int __init get_ipi_irq(void) { struct irq_domain *d =3D irq_find_matching_fwnode(cpuintc_handle, DOMAIN_= BUS_ANY); @@ -96,6 +97,7 @@ static int __init get_ipi_irq(void) =20 return -EINVAL; } +#endif =20 void __init init_IRQ(void) { diff --git a/arch/loongarch/kernel/machine_kexec.c b/arch/loongarch/kernel/= machine_kexec.c index 2dcb9e003657..8ae641dc53bb 100644 --- a/arch/loongarch/kernel/machine_kexec.c +++ b/arch/loongarch/kernel/machine_kexec.c @@ -225,6 +225,7 @@ void crash_smp_send_stop(void) =20 void machine_shutdown(void) { +#ifdef CONFIG_SMP int cpu; =20 /* All CPUs go to reboot_code_buffer */ @@ -232,7 +233,6 @@ void machine_shutdown(void) if (!cpu_online(cpu)) cpu_device_up(get_cpu_device(cpu)); =20 -#ifdef CONFIG_SMP smp_call_function(kexec_shutdown_secondary, NULL, 0); #endif } diff --git a/arch/loongarch/power/suspend.c b/arch/loongarch/power/suspend.c index 166d9e06a64b..8571818b93dc 100644 --- a/arch/loongarch/power/suspend.c +++ b/arch/loongarch/power/suspend.c @@ -24,6 +24,7 @@ struct saved_registers { u64 kpgd; u32 pwctl0; u32 pwctl1; + u64 pcpu_base; }; static struct saved_registers saved_regs; =20 @@ -36,6 +37,7 @@ void loongarch_common_suspend(void) saved_regs.pwctl1 =3D csr_read32(LOONGARCH_CSR_PWCTL1); saved_regs.ecfg =3D csr_read32(LOONGARCH_CSR_ECFG); saved_regs.euen =3D csr_read32(LOONGARCH_CSR_EUEN); + saved_regs.pcpu_base =3D csr_read64(PERCPU_BASE_KS); =20 loongarch_suspend_addr =3D loongson_sysconf.suspend_addr; } @@ -44,7 +46,7 @@ void loongarch_common_resume(void) { sync_counter(); local_flush_tlb_all(); - csr_write64(per_cpu_offset(0), PERCPU_BASE_KS); + csr_write64(saved_regs.pcpu_base, PERCPU_BASE_KS); csr_write64(eentry, LOONGARCH_CSR_EENTRY); csr_write64(eentry, LOONGARCH_CSR_MERRENTRY); csr_write64(tlbrentry, LOONGARCH_CSR_TLBRENTRY); --=20 2.42.0