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[2620:137:e000::1:20]) by mx.google.com with ESMTP id cs13-20020a170906dc8d00b006fdd5415a3fsi9715813ejc.410.2022.05.16.02.21.20; Mon, 16 May 2022 02:21:46 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com header.s=20210112 header.b=YSLyu6lv; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237187AbiEOOrX (ORCPT + 99 others); Sun, 15 May 2022 10:47:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48632 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233130AbiEOOrV (ORCPT ); Sun, 15 May 2022 10:47:21 -0400 Received: from mail-vs1-xe2d.google.com (mail-vs1-xe2d.google.com [IPv6:2607:f8b0:4864:20::e2d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6B3B2165AB; Sun, 15 May 2022 07:47:18 -0700 (PDT) Received: by mail-vs1-xe2d.google.com with SMTP id e19so13049835vsu.12; Sun, 15 May 2022 07:47:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=5QnIpuAEZs42X+q1obRU/ax5sTkR75Slj6dTZvcqhRQ=; b=YSLyu6lvKcan18/4Zh6EG5xc4O7lxfv46mYd6waDvV1bRWKog6AILBOCJrFtOg2PVf ekrvCJUdE6Eq6LeotIkOjRZ75u/tquQSBuR7Q/vj17g8ViQFoL5XuZFG6Bm1GsZy5f5P oIOMkHua7KstkE+5tYN+2QHKV779Q95EEhRJawr5/WjHElqozytcilfJfK2oGr6QJ48/ 3b/aN3wpcoCphCJv/jUlbsr3yhB77fL4p0Zj0dgYZkNt97CV1MGsLoQS0I/khWh3aWVq qIkEq2GIVkTN0+SOxCWo3genlOXIxk/L7+N8XmE65Oz2mL+68Kq4qNy4ST0m/oWipZw9 d0gw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=5QnIpuAEZs42X+q1obRU/ax5sTkR75Slj6dTZvcqhRQ=; b=6pSYSaEGKn0PoWC05CALs+OBjxS0zMtmIlQ3y5+v+fTm54YuOd423LyEUoYrBIoOhF 3PAVOXAyx0e1xBguzKTL4205cxIA75ByVCQbJANkBgPFwnHZy/V+v2vnhp3283JfkjS7 bFMQRtUbPQqfR/PuwIizylPRO171fPW2WsCZVakwPG0Ojw43fpg1WzMvA6Glt61HhZBk /YrW4FV4h3T/ZmHF6FMCiAwKgF8su0HBQC4K/K86Yl08iSovbpAmFsdpyr+fw9i0NrwQ TJSYB7vTlaoLcEae2bUie0yJmWkbZ/Ch0z4ZFyjCCSbLsu7C9GLwxUzX3CAnS352a+f/ u2Zg== X-Gm-Message-State: AOAM531OBwG0E4b9NZhPcS8PLrxRjsXD8fY12+WQfIldUmGhTqRDCOSO sIOrMtAOQDMSLtfkVSm8maKfOxmUMlviOIOnkY8= X-Received: by 2002:a67:2e91:0:b0:32c:df82:9ad3 with SMTP id u139-20020a672e91000000b0032cdf829ad3mr5016270vsu.40.1652626036924; Sun, 15 May 2022 07:47:16 -0700 (PDT) MIME-Version: 1.0 References: <20220514080402.2650181-1-chenhuacai@loongson.cn> <20220514080402.2650181-21-chenhuacai@loongson.cn> <88092b34-89ac-10e6-381c-982c5e244432@xen0n.name> In-Reply-To: <88092b34-89ac-10e6-381c-982c5e244432@xen0n.name> From: Huacai Chen Date: Sun, 15 May 2022 22:47:05 +0800 Message-ID: Subject: Re: [PATCH V10 20/22] LoongArch: Add multi-processor (SMP) support To: WANG Xuerui Cc: Huacai Chen , Arnd Bergmann , Andy Lutomirski , Thomas Gleixner , Peter Zijlstra , Andrew Morton , David Airlie , Jonathan Corbet , Linus Torvalds , linux-arch , "open list:DOCUMENTATION" , LKML , Xuefeng Li , Yanteng Si , Guo Ren , Jiaxun Yang , Stephen Rothwell Content-Type: text/plain; charset="UTF-8" X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,FREEMAIL_FROM, RCVD_IN_DNSWL_NONE,SPF_HELO_NONE,SPF_PASS,T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, Xuerui, On Sun, May 15, 2022 at 10:16 PM WANG Xuerui wrote: > > Hi, > > On 5/14/22 16:04, Huacai Chen wrote: > > LoongArch-based procesors have 4, 8 or 16 cores per package. This patch > > adds multi-processor (SMP) support for LoongArch. > > > > Signed-off-by: Huacai Chen > > --- > > arch/loongarch/Kconfig | 44 +- > > arch/loongarch/include/asm/atomic.h | 4 + > > arch/loongarch/include/asm/barrier.h | 108 ++++ > > arch/loongarch/include/asm/cmpxchg.h | 1 + > > arch/loongarch/include/asm/futex.h | 1 + > > arch/loongarch/include/asm/hardirq.h | 2 + > > arch/loongarch/include/asm/irq.h | 3 + > > arch/loongarch/include/asm/percpu.h | 194 ++++++ > > arch/loongarch/include/asm/pgtable.h | 21 + > > arch/loongarch/include/asm/smp.h | 124 ++++ > > arch/loongarch/include/asm/stackframe.h | 17 +- > > arch/loongarch/include/asm/tlbflush.h | 13 + > > arch/loongarch/include/asm/topology.h | 7 +- > > arch/loongarch/kernel/Makefile | 2 + > > arch/loongarch/kernel/acpi.c | 70 ++- > > arch/loongarch/kernel/asm-offsets.c | 10 + > > arch/loongarch/kernel/head.S | 30 + > > arch/loongarch/kernel/irq.c | 13 +- > > arch/loongarch/kernel/proc.c | 5 + > > arch/loongarch/kernel/process.c | 7 + > > arch/loongarch/kernel/reset.c | 12 + > > arch/loongarch/kernel/setup.c | 26 + > > arch/loongarch/kernel/smp.c | 744 ++++++++++++++++++++++++ > > arch/loongarch/kernel/topology.c | 43 +- > > arch/loongarch/kernel/vmlinux.lds.S | 4 + > > arch/loongarch/mm/tlbex.S | 69 +++ > > include/linux/cpuhotplug.h | 1 + > > 27 files changed, 1564 insertions(+), 11 deletions(-) > > create mode 100644 arch/loongarch/include/asm/smp.h > > create mode 100644 arch/loongarch/kernel/smp.c > > > > diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig > > index 564bd6d2c2b9..f1053d77f06e 100644 > > --- a/arch/loongarch/Kconfig > > +++ b/arch/loongarch/Kconfig > > @@ -65,6 +65,7 @@ config LOONGARCH > > select GENERIC_LIB_UCMPDI2 > > select GENERIC_PCI_IOMAP > > select GENERIC_SCHED_CLOCK > > + select GENERIC_SMP_IDLE_THREAD > > select GENERIC_TIME_VSYSCALL > > select GPIOLIB > > select HAVE_ARCH_AUDITSYSCALL > > @@ -95,7 +96,7 @@ config LOONGARCH > > select HAVE_RSEQ > > select HAVE_SYSCALL_TRACEPOINTS > > select HAVE_TIF_NOHZ > > - select HAVE_VIRT_CPU_ACCOUNTING_GEN > > + select HAVE_VIRT_CPU_ACCOUNTING_GEN if !SMP > > select IRQ_FORCED_THREADING > > select IRQ_LOONGARCH_CPU > > select MODULES_USE_ELF_RELA if MODULES > > @@ -312,6 +313,47 @@ config EFI_STUB > > This kernel feature allows the kernel to be loaded directly by > > EFI firmware without the use of a bootloader. > > > > +config SMP > > + bool "Multi-Processing support" > > + help > > + This enables support for systems with more than one CPU. If you have > > + a system with only one CPU, say N. If you have a system with more > > + than one CPU, say Y. > > + > > + If you say N here, the kernel will run on uni- and multiprocessor > > + machines, but will use only one CPU of a multiprocessor machine. If > > + you say Y here, the kernel will run on many, but not all, > > + uniprocessor machines. On a uniprocessor machine, the kernel > > + will run faster if you say N here. > > + > > + People using multiprocessor machines who say Y here should also say > > + Y to "Enhanced Real Time Clock Support", below. > This paragraph could be removed as it's not applicable to us. (We don't > have an "Enhanced RTC support" config option.) OK, thanks. > > + > > + See also the SMP-HOWTO available at > > + . > > + > > + If you don't know what to do here, say N. > > + > > +config HOTPLUG_CPU > > + bool "Support for hot-pluggable CPUs" > > + depends on SMP > > + select GENERIC_IRQ_MIGRATION > > + help > > + Say Y here to allow turning CPUs off and on. CPUs can be > > + controlled through /sys/devices/system/cpu. > > + (Note: power management support will enable this option > > + automatically on SMP systems. ) > > + Say N if you want to disable CPU hotplug. > > + > > +config NR_CPUS > > + int "Maximum number of CPUs (2-256)" > > + range 2 256 > > + depends on SMP > > + default "16" > > + help > > + This allows you to specify the maximum number of CPUs which this > > + kernel will support. > > + > > config FORCE_MAX_ZONEORDER > > int "Maximum zone order" > > range 14 64 if PAGE_SIZE_64KB > > diff --git a/arch/loongarch/include/asm/atomic.h b/arch/loongarch/include/asm/atomic.h > > index 932352342b12..979367ad4e2c 100644 > > --- a/arch/loongarch/include/asm/atomic.h > > +++ b/arch/loongarch/include/asm/atomic.h > > @@ -162,6 +162,7 @@ static inline int arch_atomic_sub_if_positive(int i, atomic_t *v) > > " sc.w %1, %2 \n" > > " beq $zero, %1, 1b \n" > > "2: \n" > > + __WEAK_LLSC_MB > > : "=&r" (result), "=&r" (temp), > > "+" GCC_OFF_SMALL_ASM() (v->counter) > > : "I" (-i)); > > @@ -174,6 +175,7 @@ static inline int arch_atomic_sub_if_positive(int i, atomic_t *v) > > " sc.w %1, %2 \n" > > " beq $zero, %1, 1b \n" > > "2: \n" > > + __WEAK_LLSC_MB > > : "=&r" (result), "=&r" (temp), > > "+" GCC_OFF_SMALL_ASM() (v->counter) > > : "r" (i)); > > @@ -323,6 +325,7 @@ static inline long arch_atomic64_sub_if_positive(long i, atomic64_t *v) > > " sc.d %1, %2 \n" > > " beq %1, $zero, 1b \n" > > "2: \n" > > + __WEAK_LLSC_MB > > : "=&r" (result), "=&r" (temp), > > "+" GCC_OFF_SMALL_ASM() (v->counter) > > : "I" (-i)); > > @@ -335,6 +338,7 @@ static inline long arch_atomic64_sub_if_positive(long i, atomic64_t *v) > > " sc.d %1, %2 \n" > > " beq %1, $zero, 1b \n" > > "2: \n" > > + __WEAK_LLSC_MB > > : "=&r" (result), "=&r" (temp), > > "+" GCC_OFF_SMALL_ASM() (v->counter) > > : "r" (i)); > > diff --git a/arch/loongarch/include/asm/barrier.h b/arch/loongarch/include/asm/barrier.h > > index cc6c7e3f5ce6..6c567c750d04 100644 > > --- a/arch/loongarch/include/asm/barrier.h > > +++ b/arch/loongarch/include/asm/barrier.h > > @@ -18,6 +18,19 @@ > > #define mb() fast_mb() > > #define iob() fast_iob() > > > > +#define __smp_mb() __asm__ __volatile__("dbar 0" : : : "memory") > > +#define __smp_rmb() __asm__ __volatile__("dbar 0" : : : "memory") > > +#define __smp_wmb() __asm__ __volatile__("dbar 0" : : : "memory") > > It's always unfortunate to see full barriers used in place of more > fine-grained barriers, but that's all we have in LoongArch v1.00... This > is life, I think, but make sure to tell the hardware engineers, that > users will be thankful for the additional barriers. ;-) OK, Loongson-3A6000 will have fine-grained barriers. > > > + > > +#ifdef CONFIG_SMP > > +#define __WEAK_LLSC_MB " dbar 0 \n" > > +#else > > +#define __WEAK_LLSC_MB " \n" > > +#endif > > + > > +#define __smp_mb__before_atomic() barrier() > > +#define __smp_mb__after_atomic() barrier() > > + > > /** > > * array_index_mask_nospec() - generate a ~0 mask when index < size, 0 otherwise > > * @index: array element index > > @@ -46,6 +59,101 @@ static inline unsigned long array_index_mask_nospec(unsigned long index, > > return mask; > > } > > > > +#define __smp_load_acquire(p) \ > > +({ \ > > + union { typeof(*p) __val; char __c[1]; } __u; \ > > + unsigned long __tmp = 0; \ > > + compiletime_assert_atomic_type(*p); \ > > + switch (sizeof(*p)) { \ > > + case 1: \ > > + *(__u8 *)__u.__c = *(volatile __u8 *)p; \ > > + __smp_mb(); \ > > + break; \ > > + case 2: \ > > + *(__u16 *)__u.__c = *(volatile __u16 *)p; \ > > + __smp_mb(); \ > > + break; \ > > + case 4: \ > > + __asm__ __volatile__( \ > > + "amor_db.w %[val], %[tmp], %[mem] \n" \ > > + : [val] "=&r" (*(__u32 *)__u.__c) \ > > + : [mem] "ZB" (*(u32 *) p), [tmp] "r" (__tmp) \ > > + : "memory"); \ > > + break; \ > > + case 8: \ > > + __asm__ __volatile__( \ > > + "amor_db.d %[val], %[tmp], %[mem] \n" \ > > + : [val] "=&r" (*(__u64 *)__u.__c) \ > > + : [mem] "ZB" (*(u64 *) p), [tmp] "r" (__tmp) \ > > + : "memory"); \ > > + break; \ > This is a little bit scary; while it's working right now it's perhaps > better to, if possible, rewrite these with generic helpers such as > READ_ONCE/WRITE_ONCE, like what arch/riscv has done. Cleanups can always > come later... > > + } \ > > + (typeof(*p))__u.__val; \ > > +}) > > + > > +#define __smp_store_release(p, v) \ > > +do { \ > > + union { typeof(*p) __val; char __c[1]; } __u = \ > > + { .__val = (__force typeof(*p)) (v) }; \ > > + unsigned long __tmp; \ > > + compiletime_assert_atomic_type(*p); \ > > + switch (sizeof(*p)) { \ > > + case 1: \ > > + __smp_mb(); \ > > + *(volatile __u8 *)p = *(__u8 *)__u.__c; \ > > + break; \ > > + case 2: \ > > + __smp_mb(); \ > > + *(volatile __u16 *)p = *(__u16 *)__u.__c; \ > > + break; \ > > + case 4: \ > > + __asm__ __volatile__( \ > > + "amswap_db.w %[tmp], %[val], %[mem] \n" \ > > + : [mem] "+ZB" (*(u32 *)p), [tmp] "=&r" (__tmp) \ > > + : [val] "r" (*(__u32 *)__u.__c) \ > > + : ); \ > > + break; \ > > + case 8: \ > > + __asm__ __volatile__( \ > > + "amswap_db.d %[tmp], %[val], %[mem] \n" \ > > + : [mem] "+ZB" (*(u64 *)p), [tmp] "=&r" (__tmp) \ > > + : [val] "r" (*(__u64 *)__u.__c) \ > > + : ); \ > > + break; \ > > + } \ > > +} while (0) > > + > > +#define __smp_store_mb(p, v) \ > > +do { \ > > + union { typeof(p) __val; char __c[1]; } __u = \ > > + { .__val = (__force typeof(p)) (v) }; \ > > + unsigned long __tmp; \ > > + switch (sizeof(p)) { \ > > + case 1: \ > > + *(volatile __u8 *)&p = *(__u8 *)__u.__c; \ > > + __smp_mb(); \ > > + break; \ > > + case 2: \ > > + *(volatile __u16 *)&p = *(__u16 *)__u.__c; \ > > + __smp_mb(); \ > > + break; \ > > + case 4: \ > > + __asm__ __volatile__( \ > > + "amswap_db.w %[tmp], %[val], %[mem] \n" \ > > + : [mem] "+ZB" (*(u32 *)&p), [tmp] "=&r" (__tmp) \ > > + : [val] "r" (*(__u32 *)__u.__c) \ > > + : ); \ > > + break; \ > > + case 8: \ > > + __asm__ __volatile__( \ > > + "amswap_db.d %[tmp], %[val], %[mem] \n" \ > > + : [mem] "+ZB" (*(u64 *)&p), [tmp] "=&r" (__tmp) \ > > + : [val] "r" (*(__u64 *)__u.__c) \ > > + : ); \ > > + break; \ > > + } \ > > +} while (0) > > + > > #include > > > > #endif /* __ASM_BARRIER_H */ > > diff --git a/arch/loongarch/include/asm/cmpxchg.h b/arch/loongarch/include/asm/cmpxchg.h > > index 699925b8ff27..7a880651161b 100644 > > --- a/arch/loongarch/include/asm/cmpxchg.h > > +++ b/arch/loongarch/include/asm/cmpxchg.h > > @@ -58,6 +58,7 @@ static inline unsigned long __xchg(volatile void *ptr, unsigned long x, > > " " st " $t0, %1 \n" \ > > " beq $zero, $t0, 1b \n" \ > > "2: \n" \ > > + __WEAK_LLSC_MB \ > > : "=&r" (__ret), "=ZB"(*m) \ > > : "ZB"(*m), "Jr" (old), "Jr" (new) \ > > : "t0", "memory"); \ > > diff --git a/arch/loongarch/include/asm/futex.h b/arch/loongarch/include/asm/futex.h > > index b27d55f92db7..9de8231694ec 100644 > > --- a/arch/loongarch/include/asm/futex.h > > +++ b/arch/loongarch/include/asm/futex.h > > @@ -86,6 +86,7 @@ futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr, u32 oldval, u32 newv > > "2: sc.w $t0, %2 \n" > > " beq $zero, $t0, 1b \n" > > "3: \n" > > + __WEAK_LLSC_MB > > " .section .fixup,\"ax\" \n" > > "4: li.d %0, %6 \n" > > " b 3b \n" > > diff --git a/arch/loongarch/include/asm/hardirq.h b/arch/loongarch/include/asm/hardirq.h > > index d32f83938880..befe8184aa08 100644 > > --- a/arch/loongarch/include/asm/hardirq.h > > +++ b/arch/loongarch/include/asm/hardirq.h > > @@ -21,4 +21,6 @@ typedef struct { > > > > DECLARE_PER_CPU_ALIGNED(irq_cpustat_t, irq_stat); > > > > +#define __ARCH_IRQ_STAT > > + > > #endif /* _ASM_HARDIRQ_H */ > > diff --git a/arch/loongarch/include/asm/irq.h b/arch/loongarch/include/asm/irq.h > > index cd95d0d4e10f..ca3a68767b54 100644 > > --- a/arch/loongarch/include/asm/irq.h > > +++ b/arch/loongarch/include/asm/irq.h > > @@ -125,6 +125,9 @@ extern struct irq_domain *pch_lpc_domain; > > extern struct irq_domain *pch_msi_domain[MAX_IO_PICS]; > > extern struct irq_domain *pch_pic_domain[MAX_IO_PICS]; > > > > +extern void fixup_irqs(void); > > +extern irqreturn_t loongson3_ipi_interrupt(int irq, void *dev); > > + > > #include > > > > #endif /* _ASM_IRQ_H */ > > diff --git a/arch/loongarch/include/asm/percpu.h b/arch/loongarch/include/asm/percpu.h > > index 7d5b22ebd834..6f0d6e6fde10 100644 > > --- a/arch/loongarch/include/asm/percpu.h > > +++ b/arch/loongarch/include/asm/percpu.h > > @@ -5,6 +5,8 @@ > > #ifndef __ASM_PERCPU_H > > #define __ASM_PERCPU_H > > > > +#include > > + > > /* Use r21 for fast access */ > > register unsigned long __my_cpu_offset __asm__("$r21"); > > > > @@ -15,6 +17,198 @@ static inline void set_my_cpu_offset(unsigned long off) > > } > > #define __my_cpu_offset __my_cpu_offset > > > > +#define PERCPU_OP(op, asm_op, c_op) \ > > +static inline unsigned long __percpu_##op(void *ptr, \ > > + unsigned long val, int size) \ > > +{ \ > > + unsigned long ret; \ > > + \ > > + switch (size) { \ > > + case 4: \ > > + __asm__ __volatile__( \ > > + "am"#asm_op".w" " %[ret], %[val], %[ptr] \n" \ > > + : [ret] "=&r" (ret), [ptr] "+ZB"(*(u32 *)ptr) \ > > + : [val] "r" (val)); \ > > + break; \ > > + case 8: \ > > + __asm__ __volatile__( \ > > + "am"#asm_op".d" " %[ret], %[val], %[ptr] \n" \ > > + : [ret] "=&r" (ret), [ptr] "+ZB"(*(u64 *)ptr) \ > > + : [val] "r" (val)); \ > > + break; \ > > + default: \ > > + ret = 0; \ > > + BUILD_BUG(); \ > > + } \ > > + \ > > + return ret c_op val; \ > > +} > > + > > +PERCPU_OP(add, add, +) > > +PERCPU_OP(and, and, &) > > +PERCPU_OP(or, or, |) > > +#undef PERCPU_OP > > + > > +static inline unsigned long __percpu_read(void *ptr, int size) > > +{ > > + unsigned long ret; > > + > > + switch (size) { > > + case 1: > > + __asm__ __volatile__ ("ldx.b %[ret], $r21, %[ptr] \n" > > + : [ret] "=&r"(ret) > > + : [ptr] "r"(ptr) > > + : "memory"); > > + break; > > + case 2: > > + __asm__ __volatile__ ("ldx.h %[ret], $r21, %[ptr] \n" > > + : [ret] "=&r"(ret) > > + : [ptr] "r"(ptr) > > + : "memory"); > > + break; > > + case 4: > > + __asm__ __volatile__ ("ldx.w %[ret], $r21, %[ptr] \n" > > + : [ret] "=&r"(ret) > > + : [ptr] "r"(ptr) > > + : "memory"); > > + break; > > + case 8: > > + __asm__ __volatile__ ("ldx.d %[ret], $r21, %[ptr] \n" > > + : [ret] "=&r"(ret) > > + : [ptr] "r"(ptr) > > + : "memory"); > > + break; > > + default: > > + ret = 0; > > + BUILD_BUG(); > > + } > > + > > + return ret; > > +} > > + > > +static inline void __percpu_write(void *ptr, unsigned long val, int size) > > +{ > > + switch (size) { > > + case 1: > > + __asm__ __volatile__("stx.b %[val], $r21, %[ptr] \n" > > + : > > + : [val] "r" (val), [ptr] "r" (ptr) > > + : "memory"); > > + break; > > + case 2: > > + __asm__ __volatile__("stx.h %[val], $r21, %[ptr] \n" > > + : > > + : [val] "r" (val), [ptr] "r" (ptr) > > + : "memory"); > > + break; > > + case 4: > > + __asm__ __volatile__("stx.w %[val], $r21, %[ptr] \n" > > + : > > + : [val] "r" (val), [ptr] "r" (ptr) > > + : "memory"); > > + break; > > + case 8: > > + __asm__ __volatile__("stx.d %[val], $r21, %[ptr] \n" > > + : > > + : [val] "r" (val), [ptr] "r" (ptr) > > + : "memory"); > > + break; > > + default: > > + BUILD_BUG(); > > + } > > +} > > + > > +static inline unsigned long __percpu_xchg(void *ptr, unsigned long val, > > + int size) > > +{ > > + switch (size) { > > + case 4: > > + return __xchg_asm("amswap.w", (volatile u32 *)ptr, (u32)val); > > + > > + case 8: > > + return __xchg_asm("amswap.d", (volatile u64 *)ptr, (u64)val); > > + > > + default: > > + BUILD_BUG(); > > + } > > + > > + return 0; > > +} > > + > > +/* this_cpu_cmpxchg */ > > +#define _protect_cmpxchg_local(pcp, o, n) \ > > +({ \ > > + typeof(*raw_cpu_ptr(&(pcp))) __ret; \ > > + preempt_disable_notrace(); \ > > + __ret = cmpxchg_local(raw_cpu_ptr(&(pcp)), o, n); \ > > + preempt_enable_notrace(); \ > > + __ret; \ > > +}) > > + > > +#define _percpu_read(pcp) \ > > +({ \ > > + typeof(pcp) __retval; \ > > + __retval = (typeof(pcp))__percpu_read(&(pcp), sizeof(pcp)); \ > > + __retval; \ > > +}) > > + > > +#define _percpu_write(pcp, val) \ > > +do { \ > > + __percpu_write(&(pcp), (unsigned long)(val), sizeof(pcp)); \ > > +} while (0) \ > > + > > +#define _pcp_protect(operation, pcp, val) \ > > +({ \ > > + typeof(pcp) __retval; \ > > + preempt_disable_notrace(); \ > > + __retval = (typeof(pcp))operation(raw_cpu_ptr(&(pcp)), \ > > + (val), sizeof(pcp)); \ > > + preempt_enable_notrace(); \ > > + __retval; \ > > +}) > > + > > +#define _percpu_add(pcp, val) \ > > + _pcp_protect(__percpu_add, pcp, val) > > + > > +#define _percpu_add_return(pcp, val) _percpu_add(pcp, val) > > + > > +#define _percpu_and(pcp, val) \ > > + _pcp_protect(__percpu_and, pcp, val) > > + > > +#define _percpu_or(pcp, val) \ > > + _pcp_protect(__percpu_or, pcp, val) > > + > > +#define _percpu_xchg(pcp, val) ((typeof(pcp)) \ > > + _pcp_protect(__percpu_xchg, pcp, (unsigned long)(val))) > > + > > +#define this_cpu_add_4(pcp, val) _percpu_add(pcp, val) > > +#define this_cpu_add_8(pcp, val) _percpu_add(pcp, val) > > + > > +#define this_cpu_add_return_4(pcp, val) _percpu_add_return(pcp, val) > > +#define this_cpu_add_return_8(pcp, val) _percpu_add_return(pcp, val) > > + > > +#define this_cpu_and_4(pcp, val) _percpu_and(pcp, val) > > +#define this_cpu_and_8(pcp, val) _percpu_and(pcp, val) > > + > > +#define this_cpu_or_4(pcp, val) _percpu_or(pcp, val) > > +#define this_cpu_or_8(pcp, val) _percpu_or(pcp, val) > > + > > +#define this_cpu_read_1(pcp) _percpu_read(pcp) > > +#define this_cpu_read_2(pcp) _percpu_read(pcp) > > +#define this_cpu_read_4(pcp) _percpu_read(pcp) > > +#define this_cpu_read_8(pcp) _percpu_read(pcp) > > + > > +#define this_cpu_write_1(pcp, val) _percpu_write(pcp, val) > > +#define this_cpu_write_2(pcp, val) _percpu_write(pcp, val) > > +#define this_cpu_write_4(pcp, val) _percpu_write(pcp, val) > > +#define this_cpu_write_8(pcp, val) _percpu_write(pcp, val) > > + > > +#define this_cpu_xchg_4(pcp, val) _percpu_xchg(pcp, val) > > +#define this_cpu_xchg_8(pcp, val) _percpu_xchg(pcp, val) > > + > > +#define this_cpu_cmpxchg_4(ptr, o, n) _protect_cmpxchg_local(ptr, o, n) > > +#define this_cpu_cmpxchg_8(ptr, o, n) _protect_cmpxchg_local(ptr, o, n) > > + > > #include > > > > #endif /* __ASM_PERCPU_H */ > > diff --git a/arch/loongarch/include/asm/pgtable.h b/arch/loongarch/include/asm/pgtable.h > > index 8920dd8b297b..5e33987d0a13 100644 > > --- a/arch/loongarch/include/asm/pgtable.h > > +++ b/arch/loongarch/include/asm/pgtable.h > > @@ -279,8 +279,29 @@ static inline void set_pte(pte_t *ptep, pte_t pteval) > > * Make sure the buddy is global too (if it's !none, > > * it better already be global) > > */ > > +#ifdef CONFIG_SMP > > + /* > > + * For SMP, multiple CPUs can race, so we need to do > > + * this atomically. > > + */ > > + unsigned long page_global = _PAGE_GLOBAL; > > + unsigned long tmp; > > + > > + __asm__ __volatile__ ( > > + "1:" __LL "%[tmp], %[buddy] \n" > > + " bnez %[tmp], 2f \n" > > + " or %[tmp], %[tmp], %[global] \n" > > + __SC "%[tmp], %[buddy] \n" > > + " beqz %[tmp], 1b \n" > > + " nop \n" > > + "2: \n" > > + __WEAK_LLSC_MB > > + : [buddy] "+m" (buddy->pte), [tmp] "=&r" (tmp) > > + : [global] "r" (page_global)); > > +#else /* !CONFIG_SMP */ > > if (pte_none(*buddy)) > > pte_val(*buddy) = pte_val(*buddy) | _PAGE_GLOBAL; > > +#endif /* CONFIG_SMP */ > > } > > } > > > > diff --git a/arch/loongarch/include/asm/smp.h b/arch/loongarch/include/asm/smp.h > > new file mode 100644 > > index 000000000000..551e1f37c705 > > --- /dev/null > > +++ b/arch/loongarch/include/asm/smp.h > > @@ -0,0 +1,124 @@ > > +/* SPDX-License-Identifier: GPL-2.0 */ > > +/* > > + * Author: Huacai Chen > > + * Copyright (C) 2020-2022 Loongson Technology Corporation Limited > > + */ > > +#ifndef __ASM_SMP_H > > +#define __ASM_SMP_H > > + > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > + > > +void loongson3_smp_setup(void); > > +void loongson3_prepare_cpus(unsigned int max_cpus); > > +void loongson3_boot_secondary(int cpu, struct task_struct *idle); > > +void loongson3_init_secondary(void); > > +void loongson3_smp_finish(void); > > +void loongson3_send_ipi_single(int cpu, unsigned int action); > > +void loongson3_send_ipi_mask(const struct cpumask *mask, unsigned int action); > > +#ifdef CONFIG_HOTPLUG_CPU > > +int loongson3_cpu_disable(void); > > +void loongson3_cpu_die(unsigned int cpu); > > +#endif > > + > > +#ifdef CONFIG_SMP > > + > > +static inline void plat_smp_setup(void) > > +{ > > + loongson3_smp_setup(); > > +} > > + > > +#else /* !CONFIG_SMP */ > > + > > +static inline void plat_smp_setup(void) { } > > + > > +#endif /* !CONFIG_SMP */ > > + > > +extern int smp_num_siblings; > > +extern int num_processors; > > +extern int disabled_cpus; > > +extern cpumask_t cpu_sibling_map[]; > > +extern cpumask_t cpu_core_map[]; > > +extern cpumask_t cpu_foreign_map[]; > > + > > +static inline int raw_smp_processor_id(void) > > +{ > > +#if defined(__VDSO__) > > + extern int vdso_smp_processor_id(void) > > + __compiletime_error("VDSO should not call smp_processor_id()"); > > + return vdso_smp_processor_id(); > > +#else > > + return current_thread_info()->cpu; > > +#endif > > +} > > +#define raw_smp_processor_id raw_smp_processor_id > > + > > +/* Map from cpu id to sequential logical cpu number. This will only > > + * not be idempotent when cpus failed to come on-line. */ > > +extern int __cpu_number_map[NR_CPUS]; > > +#define cpu_number_map(cpu) __cpu_number_map[cpu] > > + > > +/* The reverse map from sequential logical cpu number to cpu id. */ > > +extern int __cpu_logical_map[NR_CPUS]; > > +#define cpu_logical_map(cpu) __cpu_logical_map[cpu] > > + > > +#define cpu_physical_id(cpu) cpu_logical_map(cpu) > > + > > +#define SMP_BOOT_CPU 0x1 > > +#define SMP_RESCHEDULE 0x2 > > +#define SMP_CALL_FUNCTION 0x4 > > + > > +struct secondary_data { > > + unsigned long stack; > > + unsigned long thread_info; > > +}; > > +extern struct secondary_data cpuboot_data; > > + > > +extern asmlinkage void smpboot_entry(void); > > + > > +extern void calculate_cpu_foreign_map(void); > > + > > +/* > > + * Generate IPI list text > > + */ > > +extern void show_ipi_list(struct seq_file *p, int prec); > > + > > +/* > > + * This function sends a 'reschedule' IPI to another CPU. > > + * it goes straight through and wastes no time serializing > > + * anything. Worst case is that we lose a reschedule ... > > + */ > > +static inline void smp_send_reschedule(int cpu) > > +{ > > + loongson3_send_ipi_single(cpu, SMP_RESCHEDULE); > > +} > > + > > +static inline void arch_send_call_function_single_ipi(int cpu) > > +{ > > + loongson3_send_ipi_single(cpu, SMP_CALL_FUNCTION); > > +} > > + > > +static inline void arch_send_call_function_ipi_mask(const struct cpumask *mask) > > +{ > > + loongson3_send_ipi_mask(mask, SMP_CALL_FUNCTION); > > +} > > + > > +#ifdef CONFIG_HOTPLUG_CPU > > +static inline int __cpu_disable(void) > > +{ > > + return loongson3_cpu_disable(); > > +} > > + > > +static inline void __cpu_die(unsigned int cpu) > > +{ > > + loongson3_cpu_die(cpu); > > +} > > + > > +extern void play_dead(void); > > +#endif > > + > > +#endif /* __ASM_SMP_H */ > > diff --git a/arch/loongarch/include/asm/stackframe.h b/arch/loongarch/include/asm/stackframe.h > > index 44151b878d00..4ca953062b5b 100644 > > --- a/arch/loongarch/include/asm/stackframe.h > > +++ b/arch/loongarch/include/asm/stackframe.h > > @@ -77,17 +77,24 @@ > > * new value in sp. > > */ > > .macro get_saved_sp docfi=0 > > - la.abs t1, kernelsp > > - move t0, sp > > + la.abs t1, kernelsp > > +#ifdef CONFIG_SMP > > + csrrd t0, PERCPU_BASE_KS > > + LONG_ADD t1, t1, t0 > > +#endif > > + move t0, sp > > .if \docfi > > .cfi_register sp, t0 > > .endif > > - LONG_L sp, t1, 0 > > + LONG_L sp, t1, 0 > > .endm > > > > .macro set_saved_sp stackp temp temp2 > > - la.abs \temp, kernelsp > > - LONG_S \stackp, \temp, 0 > > + la.abs \temp, kernelsp > > +#ifdef CONFIG_SMP > > + LONG_ADD \temp, \temp, u0 > > +#endif > > + LONG_S \stackp, \temp, 0 > > .endm > > > > .macro SAVE_SOME docfi=0 > > diff --git a/arch/loongarch/include/asm/tlbflush.h b/arch/loongarch/include/asm/tlbflush.h > > index 36bd6d11dc2d..a0785e590681 100644 > > --- a/arch/loongarch/include/asm/tlbflush.h > > +++ b/arch/loongarch/include/asm/tlbflush.h > > @@ -25,6 +25,17 @@ extern void local_flush_tlb_kernel_range(unsigned long start, unsigned long end) > > extern void local_flush_tlb_page(struct vm_area_struct *vma, unsigned long page); > > extern void local_flush_tlb_one(unsigned long vaddr); > > > > +#ifdef CONFIG_SMP > > + > > +extern void flush_tlb_all(void); > > +extern void flush_tlb_mm(struct mm_struct *); > > +extern void flush_tlb_range(struct vm_area_struct *vma, unsigned long, unsigned long); > > +extern void flush_tlb_kernel_range(unsigned long, unsigned long); > > +extern void flush_tlb_page(struct vm_area_struct *, unsigned long); > > +extern void flush_tlb_one(unsigned long vaddr); > > + > > +#else /* CONFIG_SMP */ > > + > > #define flush_tlb_all() local_flush_tlb_all() > > #define flush_tlb_mm(mm) local_flush_tlb_mm(mm) > > #define flush_tlb_range(vma, vmaddr, end) local_flush_tlb_range(vma, vmaddr, end) > > @@ -32,4 +43,6 @@ extern void local_flush_tlb_one(unsigned long vaddr); > > #define flush_tlb_page(vma, page) local_flush_tlb_page(vma, page) > > #define flush_tlb_one(vaddr) local_flush_tlb_one(vaddr) > > > > +#endif /* CONFIG_SMP */ > > + > > #endif /* __ASM_TLBFLUSH_H */ > > diff --git a/arch/loongarch/include/asm/topology.h b/arch/loongarch/include/asm/topology.h > > index 9ac71a25207a..da135841e5b1 100644 > > --- a/arch/loongarch/include/asm/topology.h > > +++ b/arch/loongarch/include/asm/topology.h > > @@ -7,7 +7,12 @@ > > > > #include > > > > -#define cpu_logical_map(cpu) 0 > > +#ifdef CONFIG_SMP > > +#define topology_physical_package_id(cpu) (cpu_data[cpu].package) > > +#define topology_core_id(cpu) (cpu_data[cpu].core) > > +#define topology_core_cpumask(cpu) (&cpu_core_map[cpu]) > > +#define topology_sibling_cpumask(cpu) (&cpu_sibling_map[cpu]) > > +#endif > > > > #include > > > > diff --git a/arch/loongarch/kernel/Makefile b/arch/loongarch/kernel/Makefile > > index 211f12b3781c..08ddd8c90eae 100644 > > --- a/arch/loongarch/kernel/Makefile > > +++ b/arch/loongarch/kernel/Makefile > > @@ -19,4 +19,6 @@ obj-$(CONFIG_MODULES) += module.o module-sections.o > > > > obj-$(CONFIG_PROC_FS) += proc.o > > > > +obj-$(CONFIG_SMP) += smp.o > > + > > CPPFLAGS_vmlinux.lds := $(KBUILD_CFLAGS) > > diff --git a/arch/loongarch/kernel/acpi.c b/arch/loongarch/kernel/acpi.c > > index 506ab9912c51..0c7f2d1077a1 100644 > > --- a/arch/loongarch/kernel/acpi.c > > +++ b/arch/loongarch/kernel/acpi.c > > @@ -139,6 +139,35 @@ void __init acpi_boot_table_init(void) > > } > > } > > > > +static int set_processor_mask(u32 id, u32 flags) > > +{ > > + > > + int cpu, cpuid = id; > > + > > + if (num_processors >= nr_cpu_ids) { > > + pr_warn("acpi: nr_cpus/possible_cpus limit of %i reached." > pr_warn(PREFIX "nr_cpus ..."); -- make use of the common PREFIX declaration. > > + " processor 0x%x ignored.\n", nr_cpu_ids, cpuid); > > + > > + return -ENODEV; > > + > > + } > > + if (cpuid == loongson_sysconf.boot_cpu_id) > > + cpu = 0; > > + else > > + cpu = cpumask_next_zero(-1, cpu_present_mask); > > + > > + if (flags & ACPI_MADT_ENABLED) { > > + num_processors++; > > + set_cpu_possible(cpu, true); > > + set_cpu_present(cpu, true); > > + __cpu_number_map[cpuid] = cpu; > > + __cpu_logical_map[cpu] = cpuid; > > + } else > > + disabled_cpus++; > > + > > + return cpu; > > +} > > + > > static int __init > > acpi_parse_cpuintc(union acpi_subtable_headers *header, const unsigned long end) > > { > > @@ -149,6 +178,7 @@ acpi_parse_cpuintc(union acpi_subtable_headers *header, const unsigned long end) > > return -EINVAL; > > > > acpi_table_print_madt_entry(&header->common); > > + set_processor_mask(processor->core_id, processor->flags); > > > > return 0; > > } > > @@ -250,7 +280,12 @@ acpi_parse_pch_lpc(union acpi_subtable_headers *header, const unsigned long end) > > > > static void __init acpi_process_madt(void) > > { > > - int error; > > + int i, error; > > + > > + for (i = 0; i < NR_CPUS; i++) { > > + __cpu_number_map[i] = -1; > > + __cpu_logical_map[i] = -1; > > + } > > > > /* Parse MADT CPUINTC entries */ > > error = acpi_table_parse_madt(ACPI_MADT_TYPE_CORE_PIC, acpi_parse_cpuintc, MAX_CORE_PIC); > > @@ -336,3 +371,36 @@ void __init arch_reserve_mem_area(acpi_physical_address addr, size_t size) > > { > > memblock_reserve(addr, size); > > } > > + > > +#ifdef CONFIG_ACPI_HOTPLUG_CPU > > + > > +#include > > + > > +int acpi_map_cpu(acpi_handle handle, phys_cpuid_t physid, u32 acpi_id, int *pcpu) > > +{ > > + int cpu; > > + > > + cpu = set_processor_mask(physid, ACPI_MADT_ENABLED); > > + if (cpu < 0) { > > + pr_info(PREFIX "Unable to map lapic to logical cpu number\n"); > > + return cpu; > > + } > > + > > + *pcpu = cpu; > > + > > + return 0; > > +} > > +EXPORT_SYMBOL(acpi_map_cpu); > > + > > +int acpi_unmap_cpu(int cpu) > > +{ > > + set_cpu_present(cpu, false); > > + num_processors--; > > + > > + pr_info("cpu%d hot remove!\n", cpu); > > + > > + return 0; > > +} > > +EXPORT_SYMBOL(acpi_unmap_cpu); > > + > > +#endif /* CONFIG_ACPI_HOTPLUG_CPU */ > > diff --git a/arch/loongarch/kernel/asm-offsets.c b/arch/loongarch/kernel/asm-offsets.c > > index 3531e3c60a6e..bfb65eb2844f 100644 > > --- a/arch/loongarch/kernel/asm-offsets.c > > +++ b/arch/loongarch/kernel/asm-offsets.c > > @@ -252,3 +252,13 @@ void output_signal_defines(void) > > DEFINE(_SIGXFSZ, SIGXFSZ); > > BLANK(); > > } > > + > > +#ifdef CONFIG_SMP > > +void output_smpboot_defines(void) > > +{ > > + COMMENT("Linux smp cpu boot offsets."); > > + OFFSET(CPU_BOOT_STACK, secondary_data, stack); > > + OFFSET(CPU_BOOT_TINFO, secondary_data, thread_info); > > + BLANK(); > > +} > > +#endif > > diff --git a/arch/loongarch/kernel/head.S b/arch/loongarch/kernel/head.S > > index f0b3e76bb762..9f6c9f3182a5 100644 > > --- a/arch/loongarch/kernel/head.S > > +++ b/arch/loongarch/kernel/head.S > > @@ -94,4 +94,34 @@ SYM_CODE_START(kernel_entry) # kernel entry point > > > > SYM_CODE_END(kernel_entry) > > > > +#ifdef CONFIG_SMP > > + > > +/* > > + * SMP slave cpus entry point. Board specific code for bootstrap calls this > > + * function after setting up the stack and tp registers. > > + */ > > +SYM_CODE_START(smpboot_entry) > > + li.d t0, CSR_DMW0_INIT # UC, PLV0 > > + csrwr t0, LOONGARCH_CSR_DMWIN0 > > + li.d t0, CSR_DMW1_INIT # CA, PLV0 > > + csrwr t0, LOONGARCH_CSR_DMWIN1 > > + li.w t0, 0xb0 # PLV=0, IE=0, PG=1 > > + csrwr t0, LOONGARCH_CSR_CRMD > > + li.w t0, 0x04 # PLV=0, PIE=1, PWE=0 > > + csrwr t0, LOONGARCH_CSR_PRMD > > + li.w t0, 0x00 # FPE=0, SXE=0, ASXE=0, BTE=0 > > + csrwr t0, LOONGARCH_CSR_EUEN > > + > > + la.abs t0, cpuboot_data > > + ld.d sp, t0, CPU_BOOT_STACK > > + ld.d tp, t0, CPU_BOOT_TINFO > > + > > + la.abs t0, 0f > > + jirl zero, t0, 0 > > +0: > > + bl start_secondary > > +SYM_CODE_END(smpboot_entry) > > + > > +#endif /* CONFIG_SMP */ > > + > > SYM_ENTRY(kernel_entry_end, SYM_L_GLOBAL, SYM_A_NONE) > > diff --git a/arch/loongarch/kernel/irq.c b/arch/loongarch/kernel/irq.c > > index 48032ffd9331..fbb7ad1d1ac0 100644 > > --- a/arch/loongarch/kernel/irq.c > > +++ b/arch/loongarch/kernel/irq.c > > @@ -73,6 +73,9 @@ asmlinkage void spurious_interrupt(void) > > > > int arch_show_interrupts(struct seq_file *p, int prec) > > { > > +#ifdef CONFIG_SMP > > + show_ipi_list(p, prec); > > +#endif > > seq_printf(p, "%*s: %10u\n", prec, "ERR", atomic_read(&irq_err_count)); > > return 0; > > } > > @@ -108,13 +111,21 @@ void __init setup_IRQ(void) > > > > void __init init_IRQ(void) > > { > > - int i; > > + int i, r, ipi_irq; > > + static int ipi_dummy_dev; > > unsigned int order = get_order(IRQ_STACK_SIZE); > > > > clear_csr_ecfg(ECFG0_IM); > > clear_csr_estat(ESTATF_IP); > > > > setup_IRQ(); > > +#ifdef CONFIG_SMP > > + ipi_irq = get_ipi_irq(); > > + irq_set_percpu_devid(ipi_irq); > > + r = request_percpu_irq(ipi_irq, loongson3_ipi_interrupt, "IPI", &ipi_dummy_dev); > > + if (r < 0) > > + panic("IPI IRQ request failed\n"); > > +#endif > > > > for (i = 0; i < NR_IRQS; i++) > > irq_set_noprobe(i); > > diff --git a/arch/loongarch/kernel/proc.c b/arch/loongarch/kernel/proc.c > > index d1f36b510297..e5772b65f956 100644 > > --- a/arch/loongarch/kernel/proc.c > > +++ b/arch/loongarch/kernel/proc.c > > @@ -35,6 +35,11 @@ static int show_cpuinfo(struct seq_file *m, void *v) > > unsigned int fp_version = cpu_data[n].fpu_vers; > > struct proc_cpuinfo_notifier_args proc_cpuinfo_notifier_args; > > > > +#ifdef CONFIG_SMP > > + if (!cpu_online(n)) > > + return 0; > > +#endif > > + > > /* > > * For the first processor also print the system type > > */ > > diff --git a/arch/loongarch/kernel/process.c b/arch/loongarch/kernel/process.c > > index 667b365d909d..8f74985f8782 100644 > > --- a/arch/loongarch/kernel/process.c > > +++ b/arch/loongarch/kernel/process.c > > @@ -53,6 +53,13 @@ > > unsigned long boot_option_idle_override = IDLE_NO_OVERRIDE; > > EXPORT_SYMBOL(boot_option_idle_override); > > > > +#ifdef CONFIG_HOTPLUG_CPU > > +void arch_cpu_idle_dead(void) > > +{ > > + play_dead(); > > +} > > +#endif > > + > > asmlinkage void ret_from_fork(void); > > asmlinkage void ret_from_kernel_thread(void); > > > > diff --git a/arch/loongarch/kernel/reset.c b/arch/loongarch/kernel/reset.c > > index ef484ce43c5c..2b86469e4718 100644 > > --- a/arch/loongarch/kernel/reset.c > > +++ b/arch/loongarch/kernel/reset.c > > @@ -65,16 +65,28 @@ EXPORT_SYMBOL(pm_power_off); > > > > void machine_halt(void) > > { > > +#ifdef CONFIG_SMP > > + preempt_disable(); > > + smp_send_stop(); > > +#endif > > default_halt(); > > } > > > > void machine_power_off(void) > > { > > +#ifdef CONFIG_SMP > > + preempt_disable(); > > + smp_send_stop(); > > +#endif > > pm_power_off(); > > } > > > > void machine_restart(char *command) > > { > > +#ifdef CONFIG_SMP > > + preempt_disable(); > > + smp_send_stop(); > > +#endif > > do_kernel_restart(command); > > pm_restart(); > > } > > diff --git a/arch/loongarch/kernel/setup.c b/arch/loongarch/kernel/setup.c > > index 827d07204e62..c314c22cdb22 100644 > > --- a/arch/loongarch/kernel/setup.c > > +++ b/arch/loongarch/kernel/setup.c > > @@ -38,6 +38,7 @@ > > #include > > #include > > #include > > +#include > > #include > > > > #define SMBIOS_BIOSSIZE_OFFSET 0x09 > > @@ -317,6 +318,29 @@ static int __init reserve_memblock_reserved_regions(void) > > } > > arch_initcall(reserve_memblock_reserved_regions); > > > > +#ifdef CONFIG_SMP > > +static void __init prefill_possible_map(void) > > +{ > > + int i, possible; > > + > > + possible = num_processors + disabled_cpus; > > + if (possible > nr_cpu_ids) > > + possible = nr_cpu_ids; > > + > > + pr_info("SMP: Allowing %d CPUs, %d hotplug CPUs\n", > > + possible, max((possible - num_processors), 0)); > > + > > + for (i = 0; i < possible; i++) > > + set_cpu_possible(i, true); > > + for (; i < NR_CPUS; i++) > > + set_cpu_possible(i, false); > > + > > + nr_cpu_ids = possible; > > +} > > +#else > > +static inline void prefill_possible_map(void) {} > > +#endif > > + > > void __init setup_arch(char **cmdline_p) > > { > > cpu_probe(); > > @@ -331,6 +355,8 @@ void __init setup_arch(char **cmdline_p) > > arch_mem_init(cmdline_p); > > > > resource_init(); > > + plat_smp_setup(); > > + prefill_possible_map(); > > > > paging_init(); > > } > > diff --git a/arch/loongarch/kernel/smp.c b/arch/loongarch/kernel/smp.c > > new file mode 100644 > > index 000000000000..4211025c79d3 > > --- /dev/null > > +++ b/arch/loongarch/kernel/smp.c > > @@ -0,0 +1,744 @@ > > +// SPDX-License-Identifier: GPL-2.0-or-later > > +/* > > + * Copyright (C) 2020-2022 Loongson Technology Corporation Limited > > + * > > + * Derived from MIPS: > > + * Copyright (C) 2000, 2001 Kanoj Sarcar > > + * Copyright (C) 2000, 2001 Ralf Baechle > > + * Copyright (C) 2000, 2001 Silicon Graphics, Inc. > > + * Copyright (C) 2000, 2001, 2003 Broadcom Corporation > > + */ > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > + > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > + > > +int __cpu_number_map[NR_CPUS]; /* Map physical to logical */ > > +EXPORT_SYMBOL(__cpu_number_map); > > + > > +int __cpu_logical_map[NR_CPUS]; /* Map logical to physical */ > > +EXPORT_SYMBOL(__cpu_logical_map); > > + > > +/* Number of threads (siblings) per CPU core */ > > +int smp_num_siblings = 1; > > +EXPORT_SYMBOL(smp_num_siblings); > > + > > +/* Representing the threads (siblings) of each logical CPU */ > > +cpumask_t cpu_sibling_map[NR_CPUS] __read_mostly; > > +EXPORT_SYMBOL(cpu_sibling_map); > > + > > +/* Representing the core map of multi-core chips of each logical CPU */ > > +cpumask_t cpu_core_map[NR_CPUS] __read_mostly; > > +EXPORT_SYMBOL(cpu_core_map); > > + > > +static DECLARE_COMPLETION(cpu_starting); > > +static DECLARE_COMPLETION(cpu_running); > > + > > +/* > > + * A logcal cpu mask containing only one VPE per core to > > + * reduce the number of IPIs on large MT systems. > > + */ > > +cpumask_t cpu_foreign_map[NR_CPUS] __read_mostly; > > +EXPORT_SYMBOL(cpu_foreign_map); > > + > > +/* representing cpus for which sibling maps can be computed */ > > +static cpumask_t cpu_sibling_setup_map; > > + > > +/* representing cpus for which core maps can be computed */ > > +static cpumask_t cpu_core_setup_map; > > + > > +struct secondary_data cpuboot_data; > > +static DEFINE_PER_CPU(int, cpu_state); > > +DEFINE_PER_CPU_SHARED_ALIGNED(irq_cpustat_t, irq_stat); > > +EXPORT_PER_CPU_SYMBOL(irq_stat); > > + > > +enum ipi_msg_type { > > + IPI_RESCHEDULE, > > + IPI_CALL_FUNCTION, > > +}; > > + > > +static const char *ipi_types[NR_IPI] __tracepoint_string = { > > + [IPI_RESCHEDULE] = "Rescheduling interrupts", > > + [IPI_CALL_FUNCTION] = "Call Function interrupts", > "Function call interrupts" would sound more natural. Plus it's what all > other arches call it. OK, thanks. Huacai > > +}; > > + > > +void show_ipi_list(struct seq_file *p, int prec) > > +{ > > + unsigned int cpu, i; > > + > > + for (i = 0; i < NR_IPI; i++) { > > + seq_printf(p, "%*s%u:%s", prec - 1, "IPI", i, prec >= 4 ? " " : ""); > > + for_each_online_cpu(cpu) > > + seq_printf(p, "%10u ", per_cpu(irq_stat, cpu).ipi_irqs[i]); > > + seq_printf(p, " LoongArch %d %s\n", i + 1, ipi_types[i]); > > + } > > +} > > + > > +/* Send mailbox buffer via Mail_Send */ > > +static void csr_mail_send(uint64_t data, int cpu, int mailbox) > > +{ > > + uint64_t val; > > + > > + /* Send high 32 bits */ > > + val = IOCSR_MBUF_SEND_BLOCKING; > > + val |= (IOCSR_MBUF_SEND_BOX_HI(mailbox) << IOCSR_MBUF_SEND_BOX_SHIFT); > > + val |= (cpu << IOCSR_MBUF_SEND_CPU_SHIFT); > > + val |= (data & IOCSR_MBUF_SEND_H32_MASK); > > + iocsr_writeq(val, LOONGARCH_IOCSR_MBUF_SEND); > > + > > + /* Send low 32 bits */ > > + val = IOCSR_MBUF_SEND_BLOCKING; > > + val |= (IOCSR_MBUF_SEND_BOX_LO(mailbox) << IOCSR_MBUF_SEND_BOX_SHIFT); > > + val |= (cpu << IOCSR_MBUF_SEND_CPU_SHIFT); > > + val |= (data << IOCSR_MBUF_SEND_BUF_SHIFT); > > + iocsr_writeq(val, LOONGARCH_IOCSR_MBUF_SEND); > > +}; > > + > > +static u32 ipi_read_clear(int cpu) > > +{ > > + u32 action; > > + > > + /* Load the ipi register to figure out what we're supposed to do */ > > + action = iocsr_readl(LOONGARCH_IOCSR_IPI_STATUS); > > + /* Clear the ipi register to clear the interrupt */ > > + iocsr_writel(action, LOONGARCH_IOCSR_IPI_CLEAR); > > + smp_mb(); > > + > > + return action; > > +} > > + > > +static void ipi_write_action(int cpu, u32 action) > > +{ > > + unsigned int irq = 0; > > + > > + while ((irq = ffs(action))) { > > + uint32_t val = IOCSR_IPI_SEND_BLOCKING; > > + > > + val |= (irq - 1); > > + val |= (cpu << IOCSR_IPI_SEND_CPU_SHIFT); > > + iocsr_writel(val, LOONGARCH_IOCSR_IPI_SEND); > > + action &= ~BIT(irq - 1); > > + } > > +} > > + > > +void loongson3_send_ipi_single(int cpu, unsigned int action) > > +{ > > + ipi_write_action(cpu_logical_map(cpu), (u32)action); > > +} > > + > > +void loongson3_send_ipi_mask(const struct cpumask *mask, unsigned int action) > > +{ > > + unsigned int i; > > + > > + for_each_cpu(i, mask) > > + ipi_write_action(cpu_logical_map(i), (u32)action); > > +} > > + > > +irqreturn_t loongson3_ipi_interrupt(int irq, void *dev) > > +{ > > + unsigned int action; > > + unsigned int cpu = smp_processor_id(); > > + > > + action = ipi_read_clear(cpu_logical_map(cpu)); > > + > > + if (action & SMP_RESCHEDULE) { > > + scheduler_ipi(); > > + per_cpu(irq_stat, cpu).ipi_irqs[IPI_RESCHEDULE]++; > > + } > > + > > + if (action & SMP_CALL_FUNCTION) { > > + generic_smp_call_function_interrupt(); > > + per_cpu(irq_stat, cpu).ipi_irqs[IPI_CALL_FUNCTION]++; > > + } > > + > > + return IRQ_HANDLED; > > +} > > + > > +void __init loongson3_smp_setup(void) > > +{ > > + cpu_data[0].core = cpu_logical_map(0) % loongson_sysconf.cores_per_package; > > + cpu_data[0].package = cpu_logical_map(0) / loongson_sysconf.cores_per_package; > > + > > + iocsr_writel(0xffffffff, LOONGARCH_IOCSR_IPI_EN); > > + pr_info("Detected %i available CPU(s)\n", loongson_sysconf.nr_cpus); > > +} > > + > > +void __init loongson3_prepare_cpus(unsigned int max_cpus) > > +{ > > + int i = 0; > > + > > + for (i = 0; i < loongson_sysconf.nr_cpus; i++) { > > + set_cpu_present(i, true); > > + csr_mail_send(0, __cpu_logical_map[i], 0); > > + } > > + > > + per_cpu(cpu_state, smp_processor_id()) = CPU_ONLINE; > > +} > > + > > +/* > > + * Setup the PC, SP, and TP of a secondary processor and start it running! > > + */ > > +void loongson3_boot_secondary(int cpu, struct task_struct *idle) > > +{ > > + unsigned long entry; > > + > > + pr_info("Booting CPU#%d...\n", cpu); > > + > > + entry = __pa_symbol((unsigned long)&smpboot_entry); > > + cpuboot_data.stack = (unsigned long)__KSTK_TOS(idle); > > + cpuboot_data.thread_info = (unsigned long)task_thread_info(idle); > > + > > + csr_mail_send(entry, cpu_logical_map(cpu), 0); > > + > > + loongson3_send_ipi_single(cpu, SMP_BOOT_CPU); > > +} > > + > > +/* > > + * SMP init and finish on secondary CPUs > > + */ > > +void loongson3_init_secondary(void) > > +{ > > + unsigned int cpu = smp_processor_id(); > > + unsigned int imask = ECFGF_IP0 | ECFGF_IP1 | ECFGF_IP2 | > > + ECFGF_IPI | ECFGF_PMC | ECFGF_TIMER; > > + > > + change_csr_ecfg(ECFG0_IM, imask); > > + > > + iocsr_writel(0xffffffff, LOONGARCH_IOCSR_IPI_EN); > > + > > + per_cpu(cpu_state, cpu) = CPU_ONLINE; > > + cpu_data[cpu].core = > > + cpu_logical_map(cpu) % loongson_sysconf.cores_per_package; > > + cpu_data[cpu].package = > > + cpu_logical_map(cpu) / loongson_sysconf.cores_per_package; > > +} > > + > > +void loongson3_smp_finish(void) > > +{ > > + local_irq_enable(); > > + iocsr_writeq(0, LOONGARCH_IOCSR_MBUF0); > > + pr_info("CPU#%d finished\n", smp_processor_id()); > > +} > > + > > +#ifdef CONFIG_HOTPLUG_CPU > > + > > +static bool io_master(int cpu) > > +{ > > + int i, node, master; > > + > > + if (cpu == 0) > > + return true; > > + > > + for (i = 1; i < loongson_sysconf.nr_io_pics; i++) { > > + node = eiointc_get_node(i); > > + master = cpu_number_map(node * CORES_PER_EIO_NODE); > > + if (cpu == master) > > + return true; > > + } > > + > > + return false; > > +} > > + > > +int loongson3_cpu_disable(void) > > +{ > > + unsigned long flags; > > + unsigned int cpu = smp_processor_id(); > > + > > + if (io_master(cpu)) > > + return -EBUSY; > > + > > + set_cpu_online(cpu, false); > > + calculate_cpu_foreign_map(); > > + local_irq_save(flags); > > + irq_migrate_all_off_this_cpu(); > > + clear_csr_ecfg(ECFG0_IM); > > + local_irq_restore(flags); > > + local_flush_tlb_all(); > > + > > + return 0; > > +} > > + > > +void loongson3_cpu_die(unsigned int cpu) > > +{ > > + while (per_cpu(cpu_state, cpu) != CPU_DEAD) > > + cpu_relax(); > > + > > + mb(); > > +} > > + > > +/* > > + * The target CPU should go to XKPRANGE (uncached area) and flush > > + * ICache/DCache/VCache before the control CPU can safely disable its clock. > > + */ > > +static void loongson3_play_dead(int *state_addr) > > +{ > > + register int val; > > + register void *addr; > > + register void (*init_fn)(void); > > + > > + __asm__ __volatile__( > > + " li.d %[addr], 0x8000000000000000\n" > > + "1: cacop 0x8, %[addr], 0 \n" /* flush ICache */ > > + " cacop 0x8, %[addr], 1 \n" > > + " cacop 0x8, %[addr], 2 \n" > > + " cacop 0x8, %[addr], 3 \n" > > + " cacop 0x9, %[addr], 0 \n" /* flush DCache */ > > + " cacop 0x9, %[addr], 1 \n" > > + " cacop 0x9, %[addr], 2 \n" > > + " cacop 0x9, %[addr], 3 \n" > > + " addi.w %[sets], %[sets], -1 \n" > > + " addi.d %[addr], %[addr], 0x40 \n" > > + " bnez %[sets], 1b \n" > > + " li.d %[addr], 0x8000000000000000\n" > > + "2: cacop 0xa, %[addr], 0 \n" /* flush VCache */ > > + " cacop 0xa, %[addr], 1 \n" > > + " cacop 0xa, %[addr], 2 \n" > > + " cacop 0xa, %[addr], 3 \n" > > + " cacop 0xa, %[addr], 4 \n" > > + " cacop 0xa, %[addr], 5 \n" > > + " cacop 0xa, %[addr], 6 \n" > > + " cacop 0xa, %[addr], 7 \n" > > + " cacop 0xa, %[addr], 8 \n" > > + " cacop 0xa, %[addr], 9 \n" > > + " cacop 0xa, %[addr], 10 \n" > > + " cacop 0xa, %[addr], 11 \n" > > + " cacop 0xa, %[addr], 12 \n" > > + " cacop 0xa, %[addr], 13 \n" > > + " cacop 0xa, %[addr], 14 \n" > > + " cacop 0xa, %[addr], 15 \n" > > + " addi.w %[vsets], %[vsets], -1 \n" > > + " addi.d %[addr], %[addr], 0x40 \n" > > + " bnez %[vsets], 2b \n" > > + " li.w %[val], 0x7 \n" /* *state_addr = CPU_DEAD; */ > > + " st.w %[val], %[state_addr], 0 \n" > > + " dbar 0 \n" > > + " cacop 0x11, %[state_addr], 0 \n" /* flush entry of *state_addr */ > > + : [addr] "=&r" (addr), [val] "=&r" (val) > > + : [state_addr] "r" (state_addr), > > + [sets] "r" (cpu_data[smp_processor_id()].dcache.sets), > > + [vsets] "r" (cpu_data[smp_processor_id()].vcache.sets)); > > + > > + local_irq_enable(); > > + change_csr_ecfg(ECFG0_IM, ECFGF_IPI); > > + > > + __asm__ __volatile__( > > + " idle 0 \n" > > + " li.w $t0, 0x1020 \n" > > + " iocsrrd.d %[init_fn], $t0 \n" /* Get init PC */ > > + : [init_fn] "=&r" (addr) > > + : /* No Input */ > > + : "a0"); > > + init_fn = __va(addr); > > + > > + init_fn(); > > + unreachable(); > > +} > > + > > +void play_dead(void) > > +{ > > + int *state_addr; > > + unsigned int cpu = smp_processor_id(); > > + void (*play_dead_uncached)(int *s); > > + > > + idle_task_exit(); > > + play_dead_uncached = (void *)TO_UNCACHE(__pa((unsigned long)loongson3_play_dead)); > > + state_addr = &per_cpu(cpu_state, cpu); > > + mb(); > > + play_dead_uncached(state_addr); > > +} > > + > > +static int loongson3_enable_clock(unsigned int cpu) > > +{ > > + uint64_t core_id = cpu_data[cpu].core; > > + uint64_t package_id = cpu_data[cpu].package; > > + > > + LOONGSON_FREQCTRL(package_id) |= 1 << (core_id * 4 + 3); > > + > > + return 0; > > +} > > + > > +static int loongson3_disable_clock(unsigned int cpu) > > +{ > > + uint64_t core_id = cpu_data[cpu].core; > > + uint64_t package_id = cpu_data[cpu].package; > > + > > + LOONGSON_FREQCTRL(package_id) &= ~(1 << (core_id * 4 + 3)); > > + > > + return 0; > > +} > > + > > +static int register_loongson3_notifier(void) > > +{ > > + return cpuhp_setup_state_nocalls(CPUHP_LOONGARCH_SOC_PREPARE, > > + "loongarch/loongson:prepare", > > + loongson3_enable_clock, > > + loongson3_disable_clock); > > +} > > +early_initcall(register_loongson3_notifier); > > + > > +#endif > > + > > +/* > > + * Power management > > + */ > > +#ifdef CONFIG_PM > > + > > +static int loongson3_ipi_suspend(void) > > +{ > > + return 0; > > +} > > + > > +static void loongson3_ipi_resume(void) > > +{ > > + iocsr_writel(0xffffffff, LOONGARCH_IOCSR_IPI_EN); > > +} > > + > > +static struct syscore_ops loongson3_ipi_syscore_ops = { > > + .resume = loongson3_ipi_resume, > > + .suspend = loongson3_ipi_suspend, > > +}; > > + > > +/* > > + * Enable boot cpu ipi before enabling nonboot cpus > > + * during syscore_resume. > > + */ > > +static int __init ipi_pm_init(void) > > +{ > > + register_syscore_ops(&loongson3_ipi_syscore_ops); > > + return 0; > > +} > > + > > +core_initcall(ipi_pm_init); > > +#endif > > + > > +static inline void set_cpu_sibling_map(int cpu) > > +{ > > + int i; > > + > > + cpumask_set_cpu(cpu, &cpu_sibling_setup_map); > > + > > + if (smp_num_siblings <= 1) > > + cpumask_set_cpu(cpu, &cpu_sibling_map[cpu]); > > + else { > > + for_each_cpu(i, &cpu_sibling_setup_map) { > > + if (cpus_are_siblings(cpu, i)) { > > + cpumask_set_cpu(i, &cpu_sibling_map[cpu]); > > + cpumask_set_cpu(cpu, &cpu_sibling_map[i]); > > + } > > + } > > + } > > +} > > + > > +static inline void set_cpu_core_map(int cpu) > > +{ > > + int i; > > + > > + cpumask_set_cpu(cpu, &cpu_core_setup_map); > > + > > + for_each_cpu(i, &cpu_core_setup_map) { > > + if (cpu_data[cpu].package == cpu_data[i].package) { > > + cpumask_set_cpu(i, &cpu_core_map[cpu]); > > + cpumask_set_cpu(cpu, &cpu_core_map[i]); > > + } > > + } > > +} > > + > > +/* > > + * Calculate a new cpu_foreign_map mask whenever a > > + * new cpu appears or disappears. > > + */ > > +void calculate_cpu_foreign_map(void) > > +{ > > + int i, k, core_present; > > + cpumask_t temp_foreign_map; > > + > > + /* Re-calculate the mask */ > > + cpumask_clear(&temp_foreign_map); > > + for_each_online_cpu(i) { > > + core_present = 0; > > + for_each_cpu(k, &temp_foreign_map) > > + if (cpus_are_siblings(i, k)) > > + core_present = 1; > > + if (!core_present) > > + cpumask_set_cpu(i, &temp_foreign_map); > > + } > > + > > + for_each_online_cpu(i) > > + cpumask_andnot(&cpu_foreign_map[i], > > + &temp_foreign_map, &cpu_sibling_map[i]); > > +} > > + > > +/* Preload SMP state for boot cpu */ > > +void smp_prepare_boot_cpu(void) > > +{ > > + unsigned int cpu; > > + > > + set_cpu_possible(0, true); > > + set_cpu_online(0, true); > > + set_my_cpu_offset(per_cpu_offset(0)); > > + > > + for_each_possible_cpu(cpu) > > + set_cpu_numa_node(cpu, 0); > > +} > > + > > +/* called from main before smp_init() */ > > +void __init smp_prepare_cpus(unsigned int max_cpus) > > +{ > > + init_new_context(current, &init_mm); > > + current_thread_info()->cpu = 0; > > + loongson3_prepare_cpus(max_cpus); > > + set_cpu_sibling_map(0); > > + set_cpu_core_map(0); > > + calculate_cpu_foreign_map(); > > +#ifndef CONFIG_HOTPLUG_CPU > > + init_cpu_present(cpu_possible_mask); > > +#endif > > +} > > + > > +int __cpu_up(unsigned int cpu, struct task_struct *tidle) > > +{ > > + loongson3_boot_secondary(cpu, tidle); > > + > > + /* Wait for CPU to start and be ready to sync counters */ > > + if (!wait_for_completion_timeout(&cpu_starting, > > + msecs_to_jiffies(5000))) { > > + pr_crit("CPU%u: failed to start\n", cpu); > > + return -EIO; > > + } > > + > > + /* Wait for CPU to finish startup & mark itself online before return */ > > + wait_for_completion(&cpu_running); > > + > > + return 0; > > +} > > + > > +/* > > + * First C code run on the secondary CPUs after being started up by > > + * the master. > > + */ > > +asmlinkage void start_secondary(void) > > +{ > > + unsigned int cpu; > > + > > + sync_counter(); > > + cpu = smp_processor_id(); > > + set_my_cpu_offset(per_cpu_offset(cpu)); > > + > > + cpu_probe(); > > + constant_clockevent_init(); > > + loongson3_init_secondary(); > > + > > + set_cpu_sibling_map(cpu); > > + set_cpu_core_map(cpu); > > + > > + notify_cpu_starting(cpu); > > + > > + /* Notify boot CPU that we're starting */ > > + complete(&cpu_starting); > > + > > + /* The CPU is running, now mark it online */ > > + set_cpu_online(cpu, true); > > + > > + calculate_cpu_foreign_map(); > > + > > + /* > > + * Notify boot CPU that we're up & online and it can safely return > > + * from __cpu_up() > > + */ > > + complete(&cpu_running); > > + > > + /* > > + * irq will be enabled in loongson3_smp_finish(), enabling it too > > + * early is dangerous. > > + */ > > + WARN_ON_ONCE(!irqs_disabled()); > > + loongson3_smp_finish(); > > + > > + cpu_startup_entry(CPUHP_AP_ONLINE_IDLE); > > +} > > + > > +void __init smp_cpus_done(unsigned int max_cpus) > > +{ > > +} > > + > > +static void stop_this_cpu(void *dummy) > > +{ > > + set_cpu_online(smp_processor_id(), false); > > + calculate_cpu_foreign_map(); > > + local_irq_disable(); > > + while (true); > > +} > > + > > +void smp_send_stop(void) > > +{ > > + smp_call_function(stop_this_cpu, NULL, 0); > > +} > > + > > +int setup_profiling_timer(unsigned int multiplier) > > +{ > > + return 0; > > +} > > + > > +static void flush_tlb_all_ipi(void *info) > > +{ > > + local_flush_tlb_all(); > > +} > > + > > +void flush_tlb_all(void) > > +{ > > + on_each_cpu(flush_tlb_all_ipi, NULL, 1); > > +} > > + > > +static void flush_tlb_mm_ipi(void *mm) > > +{ > > + local_flush_tlb_mm((struct mm_struct *)mm); > > +} > > + > > +void flush_tlb_mm(struct mm_struct *mm) > > +{ > > + if (atomic_read(&mm->mm_users) == 0) > > + return; /* happens as a result of exit_mmap() */ > > + > > + preempt_disable(); > > + > > + if ((atomic_read(&mm->mm_users) != 1) || (current->mm != mm)) { > > + on_each_cpu_mask(mm_cpumask(mm), flush_tlb_mm_ipi, mm, 1); > > + } else { > > + unsigned int cpu; > > + > > + for_each_online_cpu(cpu) { > > + if (cpu != smp_processor_id() && cpu_context(cpu, mm)) > > + cpu_context(cpu, mm) = 0; > > + } > > + local_flush_tlb_mm(mm); > > + } > > + > > + preempt_enable(); > > +} > > + > > +struct flush_tlb_data { > > + struct vm_area_struct *vma; > > + unsigned long addr1; > > + unsigned long addr2; > > +}; > > + > > +static void flush_tlb_range_ipi(void *info) > > +{ > > + struct flush_tlb_data *fd = info; > > + > > + local_flush_tlb_range(fd->vma, fd->addr1, fd->addr2); > > +} > > + > > +void flush_tlb_range(struct vm_area_struct *vma, unsigned long start, unsigned long end) > > +{ > > + struct mm_struct *mm = vma->vm_mm; > > + > > + preempt_disable(); > > + if ((atomic_read(&mm->mm_users) != 1) || (current->mm != mm)) { > > + struct flush_tlb_data fd = { > > + .vma = vma, > > + .addr1 = start, > > + .addr2 = end, > > + }; > > + > > + on_each_cpu_mask(mm_cpumask(mm), flush_tlb_range_ipi, &fd, 1); > > + } else { > > + unsigned int cpu; > > + int exec = vma->vm_flags & VM_EXEC; > > + > > + for_each_online_cpu(cpu) { > > + /* > > + * flush_cache_range() will only fully flush icache if > > + * the VMA is executable, otherwise we must invalidate > > + * ASID without it appearing to has_valid_asid() as if > > + * mm has been completely unused by that CPU. > > + */ > > + if (cpu != smp_processor_id() && cpu_context(cpu, mm)) > > + cpu_context(cpu, mm) = !exec; > > + } > > + local_flush_tlb_range(vma, start, end); > > + } > > + preempt_enable(); > > +} > > + > > +static void flush_tlb_kernel_range_ipi(void *info) > > +{ > > + struct flush_tlb_data *fd = info; > > + > > + local_flush_tlb_kernel_range(fd->addr1, fd->addr2); > > +} > > + > > +void flush_tlb_kernel_range(unsigned long start, unsigned long end) > > +{ > > + struct flush_tlb_data fd = { > > + .addr1 = start, > > + .addr2 = end, > > + }; > > + > > + on_each_cpu(flush_tlb_kernel_range_ipi, &fd, 1); > > +} > > + > > +static void flush_tlb_page_ipi(void *info) > > +{ > > + struct flush_tlb_data *fd = info; > > + > > + local_flush_tlb_page(fd->vma, fd->addr1); > > +} > > + > > +void flush_tlb_page(struct vm_area_struct *vma, unsigned long page) > > +{ > > + preempt_disable(); > > + if ((atomic_read(&vma->vm_mm->mm_users) != 1) || (current->mm != vma->vm_mm)) { > > + struct flush_tlb_data fd = { > > + .vma = vma, > > + .addr1 = page, > > + }; > > + > > + on_each_cpu_mask(mm_cpumask(vma->vm_mm), flush_tlb_page_ipi, &fd, 1); > > + } else { > > + unsigned int cpu; > > + > > + for_each_online_cpu(cpu) { > > + /* > > + * flush_cache_page() only does partial flushes, so > > + * invalidate ASID without it appearing to > > + * has_valid_asid() as if mm has been completely unused > > + * by that CPU. > > + */ > > + if (cpu != smp_processor_id() && cpu_context(cpu, vma->vm_mm)) > > + cpu_context(cpu, vma->vm_mm) = 1; > > + } > > + local_flush_tlb_page(vma, page); > > + } > > + preempt_enable(); > > +} > > +EXPORT_SYMBOL(flush_tlb_page); > > + > > +static void flush_tlb_one_ipi(void *info) > > +{ > > + unsigned long vaddr = (unsigned long) info; > > + > > + local_flush_tlb_one(vaddr); > > +} > > + > > +void flush_tlb_one(unsigned long vaddr) > > +{ > > + on_each_cpu(flush_tlb_one_ipi, (void *)vaddr, 1); > > +} > > +EXPORT_SYMBOL(flush_tlb_one); > > diff --git a/arch/loongarch/kernel/topology.c b/arch/loongarch/kernel/topology.c > > index 3b2cbb95875b..ab1a75c0b5a6 100644 > > --- a/arch/loongarch/kernel/topology.c > > +++ b/arch/loongarch/kernel/topology.c > > @@ -1,13 +1,52 @@ > > // SPDX-License-Identifier: GPL-2.0 > > #include > > +#include > > #include > > +#include > > +#include > > #include > > > > -static struct cpu cpu_device; > > +static DEFINE_PER_CPU(struct cpu, cpu_devices); > > + > > +#ifdef CONFIG_HOTPLUG_CPU > > +int arch_register_cpu(int cpu) > > +{ > > + int ret; > > + struct cpu *c = &per_cpu(cpu_devices, cpu); > > + > > + c->hotpluggable = 1; > > + ret = register_cpu(c, cpu); > > + if (ret < 0) > > + pr_warn("register_cpu %d failed (%d)\n", cpu, ret); > > + > > + return ret; > > +} > > +EXPORT_SYMBOL(arch_register_cpu); > > + > > +void arch_unregister_cpu(int cpu) > > +{ > > + struct cpu *c = &per_cpu(cpu_devices, cpu); > > + > > + c->hotpluggable = 0; > > + unregister_cpu(c); > > +} > > +EXPORT_SYMBOL(arch_unregister_cpu); > > +#endif > > > > static int __init topology_init(void) > > { > > - return register_cpu(&cpu_device, 0); > > + int i, ret; > > + > > + for_each_present_cpu(i) { > > + struct cpu *c = &per_cpu(cpu_devices, i); > > + > > + c->hotpluggable = !!i; > > + ret = register_cpu(c, i); > > + if (ret < 0) > > + pr_warn("topology_init: register_cpu %d failed (%d)\n", i, ret); > > + } > > + > > + return 0; > > } > > > > subsys_initcall(topology_init); > > diff --git a/arch/loongarch/kernel/vmlinux.lds.S b/arch/loongarch/kernel/vmlinux.lds.S > > index 7da4c4d7c50d..006cbb1bd5c6 100644 > > --- a/arch/loongarch/kernel/vmlinux.lds.S > > +++ b/arch/loongarch/kernel/vmlinux.lds.S > > @@ -73,6 +73,10 @@ SECTIONS > > EXIT_DATA > > } > > > > +#ifdef CONFIG_SMP > > + PERCPU_SECTION(1 << CONFIG_L1_CACHE_SHIFT) > > +#endif > > + > > .init.bss : { > > *(.init.bss) > > } > > diff --git a/arch/loongarch/mm/tlbex.S b/arch/loongarch/mm/tlbex.S > > index a4ca4e507ee8..606b7800edc6 100644 > > --- a/arch/loongarch/mm/tlbex.S > > +++ b/arch/loongarch/mm/tlbex.S > > @@ -88,7 +88,14 @@ vmalloc_done_load: > > slli.d t0, t0, _PTE_T_LOG2 > > add.d t1, ra, t0 > > > > +#ifdef CONFIG_SMP > > +smp_pgtable_change_load: > > +#endif > > +#ifdef CONFIG_SMP > > + ll.d t0, t1, 0 > > +#else > > ld.d t0, t1, 0 > > +#endif > > tlbsrch > > > > srli.d ra, t0, _PAGE_PRESENT_SHIFT > > @@ -96,7 +103,12 @@ vmalloc_done_load: > > beq ra, $r0, nopage_tlb_load > > > > ori t0, t0, _PAGE_VALID > > +#ifdef CONFIG_SMP > > + sc.d t0, t1, 0 > > + beq t0, $r0, smp_pgtable_change_load > > +#else > > st.d t0, t1, 0 > > +#endif > > ori t1, t1, 8 > > xori t1, t1, 8 > > ld.d t0, t1, 0 > > @@ -120,14 +132,24 @@ vmalloc_load: > > * spots a huge page. > > */ > > tlb_huge_update_load: > > +#ifdef CONFIG_SMP > > + ll.d t0, t1, 0 > > +#else > > ld.d t0, t1, 0 > > +#endif > > srli.d ra, t0, _PAGE_PRESENT_SHIFT > > andi ra, ra, 1 > > beq ra, $r0, nopage_tlb_load > > tlbsrch > > > > ori t0, t0, _PAGE_VALID > > +#ifdef CONFIG_SMP > > + sc.d t0, t1, 0 > > + beq t0, $r0, tlb_huge_update_load > > + ld.d t0, t1, 0 > > +#else > > st.d t0, t1, 0 > > +#endif > > addu16i.d t1, $r0, -(CSR_TLBIDX_EHINV >> 16) > > addi.d ra, t1, 0 > > csrxchg ra, t1, LOONGARCH_CSR_TLBIDX > > @@ -173,6 +195,7 @@ tlb_huge_update_load: > > csrxchg t1, t0, LOONGARCH_CSR_TLBIDX > > > > nopage_tlb_load: > > + dbar 0 > > csrrd ra, EXCEPTION_KS2 > > la.abs t0, tlb_do_page_fault_0 > > jirl $r0, t0, 0 > > @@ -229,7 +252,14 @@ vmalloc_done_store: > > slli.d t0, t0, _PTE_T_LOG2 > > add.d t1, ra, t0 > > > > +#ifdef CONFIG_SMP > > +smp_pgtable_change_store: > > +#endif > > +#ifdef CONFIG_SMP > > + ll.d t0, t1, 0 > > +#else > > ld.d t0, t1, 0 > > +#endif > > tlbsrch > > > > srli.d ra, t0, _PAGE_PRESENT_SHIFT > > @@ -238,7 +268,12 @@ vmalloc_done_store: > > bne ra, $r0, nopage_tlb_store > > > > ori t0, t0, (_PAGE_VALID | _PAGE_DIRTY | _PAGE_MODIFIED) > > +#ifdef CONFIG_SMP > > + sc.d t0, t1, 0 > > + beq t0, $r0, smp_pgtable_change_store > > +#else > > st.d t0, t1, 0 > > +#endif > > > > ori t1, t1, 8 > > xori t1, t1, 8 > > @@ -263,7 +298,11 @@ vmalloc_store: > > * spots a huge page. > > */ > > tlb_huge_update_store: > > +#ifdef CONFIG_SMP > > + ll.d t0, t1, 0 > > +#else > > ld.d t0, t1, 0 > > +#endif > > srli.d ra, t0, _PAGE_PRESENT_SHIFT > > andi ra, ra, ((_PAGE_PRESENT | _PAGE_WRITE) >> _PAGE_PRESENT_SHIFT) > > xori ra, ra, ((_PAGE_PRESENT | _PAGE_WRITE) >> _PAGE_PRESENT_SHIFT) > > @@ -272,7 +311,13 @@ tlb_huge_update_store: > > tlbsrch > > ori t0, t0, (_PAGE_VALID | _PAGE_DIRTY | _PAGE_MODIFIED) > > > > +#ifdef CONFIG_SMP > > + sc.d t0, t1, 0 > > + beq t0, $r0, tlb_huge_update_store > > + ld.d t0, t1, 0 > > +#else > > st.d t0, t1, 0 > > +#endif > > addu16i.d t1, $r0, -(CSR_TLBIDX_EHINV >> 16) > > addi.d ra, t1, 0 > > csrxchg ra, t1, LOONGARCH_CSR_TLBIDX > > @@ -318,6 +363,7 @@ tlb_huge_update_store: > > csrxchg t1, t0, LOONGARCH_CSR_TLBIDX > > > > nopage_tlb_store: > > + dbar 0 > > csrrd ra, EXCEPTION_KS2 > > la.abs t0, tlb_do_page_fault_1 > > jirl $r0, t0, 0 > > @@ -373,7 +419,14 @@ vmalloc_done_modify: > > slli.d t0, t0, _PTE_T_LOG2 > > add.d t1, ra, t0 > > > > +#ifdef CONFIG_SMP > > +smp_pgtable_change_modify: > > +#endif > > +#ifdef CONFIG_SMP > > + ll.d t0, t1, 0 > > +#else > > ld.d t0, t1, 0 > > +#endif > > tlbsrch > > > > srli.d ra, t0, _PAGE_WRITE_SHIFT > > @@ -381,7 +434,12 @@ vmalloc_done_modify: > > beq ra, $r0, nopage_tlb_modify > > > > ori t0, t0, (_PAGE_VALID | _PAGE_DIRTY | _PAGE_MODIFIED) > > +#ifdef CONFIG_SMP > > + sc.d t0, t1, 0 > > + beq t0, $r0, smp_pgtable_change_modify > > +#else > > st.d t0, t1, 0 > > +#endif > > ori t1, t1, 8 > > xori t1, t1, 8 > > ld.d t0, t1, 0 > > @@ -405,7 +463,11 @@ vmalloc_modify: > > * build_tlbchange_handler_head spots a huge page. > > */ > > tlb_huge_update_modify: > > +#ifdef CONFIG_SMP > > + ll.d t0, t1, 0 > > +#else > > ld.d t0, t1, 0 > > +#endif > > > > srli.d ra, t0, _PAGE_WRITE_SHIFT > > andi ra, ra, 1 > > @@ -414,7 +476,13 @@ tlb_huge_update_modify: > > tlbsrch > > ori t0, t0, (_PAGE_VALID | _PAGE_DIRTY | _PAGE_MODIFIED) > > > > +#ifdef CONFIG_SMP > > + sc.d t0, t1, 0 > > + beq t0, $r0, tlb_huge_update_modify > > + ld.d t0, t1, 0 > > +#else > > st.d t0, t1, 0 > > +#endif > > /* > > * A huge PTE describes an area the size of the > > * configured huge page size. This is twice the > > @@ -454,6 +522,7 @@ tlb_huge_update_modify: > > csrxchg t1, t0, LOONGARCH_CSR_TLBIDX > > > > nopage_tlb_modify: > > + dbar 0 > > csrrd ra, EXCEPTION_KS2 > > la.abs t0, tlb_do_page_fault_1 > > jirl $r0, t0, 0 > > diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h > > index 2af7c6587875..8abd28c4f32b 100644 > > --- a/include/linux/cpuhotplug.h > > +++ b/include/linux/cpuhotplug.h > > @@ -130,6 +130,7 @@ enum cpuhp_state { > > CPUHP_ZCOMP_PREPARE, > > CPUHP_TIMERS_PREPARE, > > CPUHP_MIPS_SOC_PREPARE, > > + CPUHP_LOONGARCH_SOC_PREPARE, > > CPUHP_BP_PREPARE_DYN, > > CPUHP_BP_PREPARE_DYN_END = CPUHP_BP_PREPARE_DYN + 20, > > CPUHP_BRINGUP_CPU, > > All of this looks reasonable, not that I write kernel code day and > night, but maybe I just read too much arch/mips code in the past years > and the changes here look natural to me. And the names and code flows > are sensible enough that people moderately familiar with the kernel > (such as me) could easily follow. > > So, like with some earlier patches, a rather weak: > > Reviewed-by: WANG Xuerui >