MIPS: mm: Place per_cpu on different nodes, if NUMA is enabled
authorThomas Bogendoerfer <tbogendoerfer@suse.de>
Thu, 9 Jan 2020 12:23:31 +0000 (13:23 +0100)
committerPaul Burton <paulburton@kernel.org>
Thu, 9 Jan 2020 17:54:30 +0000 (09:54 -0800)
Implement placing of per_cpu into memory, which is local to the CPU.

Signed-off-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
Signed-off-by: Paul Burton <paulburton@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: James Hogan <jhogan@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
arch/mips/Kconfig
arch/mips/mm/init.c

index ed8e28b..cf56b32 100644 (file)
@@ -2696,6 +2696,14 @@ config NUMA
 config SYS_SUPPORTS_NUMA
        bool
 
+config HAVE_SETUP_PER_CPU_AREA
+       def_bool y
+       depends on NUMA
+
+config NEED_PER_CPU_EMBED_FIRST_CHUNK
+       def_bool y
+       depends on NUMA
+
 config RELOCATABLE
        bool "Relocatable kernel"
        depends on SYS_SUPPORTS_RELOCATABLE && (CPU_MIPS32_R2 || CPU_MIPS64_R2 || CPU_MIPS32_R6 || CPU_MIPS64_R6 || CAVIUM_OCTEON_SOC)
index 50f9ed8..7968400 100644 (file)
@@ -508,6 +508,51 @@ void __ref free_initmem(void)
                free_initmem_default(POISON_FREE_INITMEM);
 }
 
+#ifdef CONFIG_HAVE_SETUP_PER_CPU_AREA
+unsigned long __per_cpu_offset[NR_CPUS] __read_mostly;
+EXPORT_SYMBOL(__per_cpu_offset);
+
+static int __init pcpu_cpu_distance(unsigned int from, unsigned int to)
+{
+       return node_distance(cpu_to_node(from), cpu_to_node(to));
+}
+
+static void * __init pcpu_fc_alloc(unsigned int cpu, size_t size,
+                                      size_t align)
+{
+       return memblock_alloc_try_nid(size, align, __pa(MAX_DMA_ADDRESS),
+                                     MEMBLOCK_ALLOC_ACCESSIBLE,
+                                     cpu_to_node(cpu));
+}
+
+static void __init pcpu_fc_free(void *ptr, size_t size)
+{
+       memblock_free_early(__pa(ptr), size);
+}
+
+void __init setup_per_cpu_areas(void)
+{
+       unsigned long delta;
+       unsigned int cpu;
+       int rc;
+
+       /*
+        * Always reserve area for module percpu variables.  That's
+        * what the legacy allocator did.
+        */
+       rc = pcpu_embed_first_chunk(PERCPU_MODULE_RESERVE,
+                                   PERCPU_DYNAMIC_RESERVE, PAGE_SIZE,
+                                   pcpu_cpu_distance,
+                                   pcpu_fc_alloc, pcpu_fc_free);
+       if (rc < 0)
+               panic("Failed to initialize percpu areas.");
+
+       delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start;
+       for_each_possible_cpu(cpu)
+               __per_cpu_offset[cpu] = delta + pcpu_unit_offsets[cpu];
+}
+#endif
+
 #ifndef CONFIG_MIPS_PGD_C0_CONTEXT
 unsigned long pgd_current[NR_CPUS];
 #endif