From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 179EFCE7A81 for ; Mon, 25 Sep 2023 07:54:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=gthnfcIXV+eKcFTy/3KnFjVGT4WuJwkjPLM6lscx78c=; b=uFUsJiIZ9f9kx1 JkQ7hcUqE0B5OVFaCg8uYHEJj2QPctZUJh6pgyt55/8UKyc4MmzdAsuOgJ1Cs5mXUU+T239DcqPEw ECSqEkUESSrK1zQ5eGL705MOSNGlTeFnTcOW/mrOYQKpsRoGqex3R0cYl1PQmRjmrz+NcVxYTgdxY 6/vOJgduigRWBqSZSzT5TXDvzIvOzoRphbeQhpJKfr6eCnS0ejJoQKTS+cWk+R8CuQrbltBW/bfsy EeN+A4OTBWTIDMNvi6K57Snl8KOWGBvRrBvmBaqxDiDB6nG0pUjs+0ZHgT20l4wdYVxK/hKrJbIPC KtHTHs3KtgAdqRg59WJA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qkgQF-00DfMb-11; Mon, 25 Sep 2023 07:54:27 +0000 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1qkgQB-00DfLf-2G for kexec@lists.infradead.org; Mon, 25 Sep 2023 07:54:25 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1695628462; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=RtrOhv5fXa0UyBpIzqyErWyqoITr8ir4rTLTZFqFk0k=; b=XJIrrRBQKf3t1hGqaDVkBJyQL0eNqIFZt20zyiQwrJmikzMZKATPxqZJfpbHFRQUgg2H+Y tOVawDueaDJCawC3UQ4hewN5uoNnt+gL+/HMUZLyS5HyPBN3f+xOGLnoA2B508SuTuiKHw sGieNre0yi1hLMFXCVpgS9JqF+ecYAI= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-591-1zQ7DQyrPSaXWY06M_-A8Q-1; Mon, 25 Sep 2023 03:54:18 -0400 X-MC-Unique: 1zQ7DQyrPSaXWY06M_-A8Q-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.rdu2.redhat.com [10.11.54.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 2D1DF8032FE; Mon, 25 Sep 2023 07:54:18 +0000 (UTC) Received: from piliu.users.ipa.redhat.com (unknown [10.72.120.2]) by smtp.corp.redhat.com (Postfix) with ESMTP id 4BB3A40C6EA8; Mon, 25 Sep 2023 07:54:13 +0000 (UTC) From: Pingfan Liu To: linuxppc-dev@lists.ozlabs.org Cc: Pingfan Liu , Michael Ellerman , Nicholas Piggin , Christophe Leroy , Mahesh Salgaonkar , Wen Xiong , Baoquan He , Ming Lei , kexec@lists.infradead.org Subject: [PATCHv7 2/4] powerpc/setup: Loosen the mapping between cpu logical id and its seq in dt Date: Mon, 25 Sep 2023 15:53:46 +0800 Message-Id: <20230925075348.16654-3-piliu@redhat.com> In-Reply-To: <20230925075348.16654-1-piliu@redhat.com> References: <20230925075348.16654-1-piliu@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.2 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230925_005423_808645_A8A1D122 X-CRM114-Status: GOOD ( 28.32 ) X-BeenThere: kexec@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "kexec" Errors-To: kexec-bounces+kexec=archiver.kernel.org@lists.infradead.org *** Idea *** For kexec -p, the boot cpu can be not the cpu0, this causes the problem of allocating memory for paca_ptrs[]. However, in theory, there is no requirement to assign cpu's logical id as its present sequence in the device tree. But there is something like cpu_first_thread_sibling(), which makes assumption on the mapping inside a core. Hence partially loosening the mapping, i.e. unbind the mapping of core while keep the mapping inside a core. *** Implement *** At this early stage, there are plenty of memory to utilize. Hence, this patch allocates interim memory to link the cpu info on a list, then reorder cpus by changing the list head. As a result, there is a rotate shift between the sequence number in dt and the cpu logical number. *** Result *** After this patch, a boot-cpu's logical id will always be mapped into the range [0,threads_per_core). Besides this, at this phase, all threads in the boot core are forced to be onlined. This restriction will be lifted in a later patch with extra effort. Signed-off-by: Pingfan Liu Cc: Michael Ellerman Cc: Nicholas Piggin Cc: Christophe Leroy Cc: Mahesh Salgaonkar Cc: Wen Xiong Cc: Baoquan He Cc: Ming Lei Cc: kexec@lists.infradead.org To: linuxppc-dev@lists.ozlabs.org --- arch/powerpc/kernel/prom.c | 25 +++++---- arch/powerpc/kernel/setup-common.c | 87 +++++++++++++++++++++++------- 2 files changed, 85 insertions(+), 27 deletions(-) diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c index ec82f5bda908..87272a2d8c10 100644 --- a/arch/powerpc/kernel/prom.c +++ b/arch/powerpc/kernel/prom.c @@ -76,7 +76,9 @@ u64 ppc64_rma_size; unsigned int boot_cpu_node_count __ro_after_init; #endif static phys_addr_t first_memblock_size; +#ifdef CONFIG_SMP static int __initdata boot_cpu_count; +#endif static int __init early_parse_mem(char *p) { @@ -331,8 +333,7 @@ static int __init early_init_dt_scan_cpus(unsigned long node, const __be32 *intserv; int i, nthreads; int len; - int found = -1; - int found_thread = 0; + bool found = false; /* We are scanning "cpu" nodes only */ if (type == NULL || strcmp(type, "cpu") != 0) @@ -355,8 +356,15 @@ static int __init early_init_dt_scan_cpus(unsigned long node, for (i = 0; i < nthreads; i++) { if (be32_to_cpu(intserv[i]) == fdt_boot_cpuid_phys(initial_boot_params)) { - found = boot_cpu_count; - found_thread = i; + /* + * always map the boot-cpu logical id into the + * range of [0, thread_per_core) + */ + boot_cpuid = i; + found = true; + /* This works around the hole in paca_ptrs[]. */ + if (nr_cpu_ids < nthreads) + set_nr_cpu_ids(nthreads); } #ifdef CONFIG_SMP /* logical cpu id is always 0 on UP kernels */ @@ -365,14 +373,13 @@ static int __init early_init_dt_scan_cpus(unsigned long node, } /* Not the boot CPU */ - if (found < 0) + if (!found) return 0; - DBG("boot cpu: logical %d physical %d\n", found, - be32_to_cpu(intserv[found_thread])); - boot_cpuid = found; + DBG("boot cpu: logical %d physical %d\n", boot_cpuid, + be32_to_cpu(intserv[boot_cpuid])); - boot_cpu_hwid = be32_to_cpu(intserv[found_thread]); + boot_cpu_hwid = be32_to_cpu(intserv[boot_cpuid]); /* * PAPR defines "logical" PVR values for cpus that diff --git a/arch/powerpc/kernel/setup-common.c b/arch/powerpc/kernel/setup-common.c index 1b19a9815672..f6d32324b5a5 100644 --- a/arch/powerpc/kernel/setup-common.c +++ b/arch/powerpc/kernel/setup-common.c @@ -36,6 +36,7 @@ #include #include #include +#include #include #include #include @@ -425,6 +426,13 @@ static void __init cpu_init_thread_core_maps(int tpc) u32 *cpu_to_phys_id = NULL; +struct interrupt_server_node { + struct list_head node; + bool avail; + int len; + __be32 *intserv; +}; + /** * setup_cpu_maps - initialize the following cpu maps: * cpu_possible_mask @@ -446,11 +454,16 @@ u32 *cpu_to_phys_id = NULL; void __init smp_setup_cpu_maps(void) { struct device_node *dn; - int cpu = 0; - int nthreads = 1; + int shift = 0, cpu = 0; + int j, nthreads = 1; + int len; + struct interrupt_server_node *intserv_node, *n; + struct list_head *bt_node, head; + bool avail, found_boot_cpu = false; DBG("smp_setup_cpu_maps()\n"); + INIT_LIST_HEAD(&head); cpu_to_phys_id = memblock_alloc(nr_cpu_ids * sizeof(u32), __alignof__(u32)); if (!cpu_to_phys_id) @@ -460,7 +473,6 @@ void __init smp_setup_cpu_maps(void) for_each_node_by_type(dn, "cpu") { const __be32 *intserv; __be32 cpu_be; - int j, len; DBG(" * %pOF...\n", dn); @@ -480,29 +492,68 @@ void __init smp_setup_cpu_maps(void) } } - nthreads = len / sizeof(int); - - for (j = 0; j < nthreads && cpu < nr_cpu_ids; j++) { - bool avail; + avail = of_device_is_available(dn); + if (!avail) + avail = !of_property_match_string(dn, + "enable-method", "spin-table"); - DBG(" thread %d -> cpu %d (hard id %d)\n", - j, cpu, be32_to_cpu(intserv[j])); - avail = of_device_is_available(dn); - if (!avail) - avail = !of_property_match_string(dn, - "enable-method", "spin-table"); + intserv_node = memblock_alloc(sizeof(struct interrupt_server_node) + len, + __alignof__(u32)); + if (!intserv_node) + panic("%s: Failed to allocate %zu bytes align=0x%zx\n", + __func__, + sizeof(struct interrupt_server_node) + len, + __alignof__(u32)); + intserv_node->intserv = (__be32 *)((char *)intserv_node + + sizeof(struct interrupt_server_node)); + intserv_node->len = len; + memcpy(intserv_node->intserv, intserv, len); + intserv_node->avail = avail; + INIT_LIST_HEAD(&intserv_node->node); + list_add_tail(&intserv_node->node, &head); + + if (!found_boot_cpu) { + nthreads = len / sizeof(int); + for (j = 0 ; j < nthreads; j++) { + if (be32_to_cpu(intserv[j]) == boot_cpu_hwid) { + bt_node = &intserv_node->node; + found_boot_cpu = true; + /* + * Record the round-shift between dt + * seq and cpu logical number + */ + shift = cpu - j; + break; + } + + cpu++; + } + } + } + cpu = 0; + list_del_init(&head); + /* Select the primary thread, the boot cpu's slibing, as the logic 0 */ + list_add_tail(&head, bt_node); + pr_info("the round shift between dt seq and the cpu logic number: %d\n", shift); + list_for_each_entry(intserv_node, &head, node) { + + avail = intserv_node->avail; + nthreads = intserv_node->len / sizeof(int); + for (j = 0; j < nthreads && cpu < nr_cpu_ids; j++) { set_cpu_present(cpu, avail); set_cpu_possible(cpu, true); - cpu_to_phys_id[cpu] = be32_to_cpu(intserv[j]); + cpu_to_phys_id[cpu] = be32_to_cpu(intserv_node->intserv[j]); + DBG(" thread %d -> cpu %d (hard id %d)\n", + j, cpu, be32_to_cpu(intserv[j])); cpu++; } + } - if (cpu >= nr_cpu_ids) { - of_node_put(dn); - break; - } + list_for_each_entry_safe(intserv_node, n, &head, node) { + len = sizeof(struct interrupt_server_node) + intserv_node->len; + memblock_free(intserv_node, len); } /* If no SMT supported, nthreads is forced to 1 */ -- 2.31.1 _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec