[PATCH] x86: sutomatically enable bigsmp when we have more than 8 CPUs

i386 generic subarchitecture requires explicit dmi strings or command line to enable bigsmp mode. The patch below removes that restriction, and uses bigsmp as soon as it finds more than 8 logical CPUs, Intel processors and xAPIC support. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] x86: sutomatically enable bigsmp when we have more than 8 CPUs
i386 generic subarchitecture requires explicit dmi strings or command line to enable bigsmp mode. The patch below removes that restriction, and uses bigsmp as soon as it finds more than 8 logical CPUs, Intel processors and xAPIC support. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Venkatesh Pallipadi · Linus Torvalds
1 parent 484b90c4b9
Showing 8 changed files with 47 additions and 2 deletions Side-by-side Diff
arch/i386/kernel/acpi/boot.c
arch/i386/kernel/mpparse.c
arch/i386/kernel/setup.c
arch/i386/mach-generic/bigsmp.c
arch/i386/mach-generic/probe.c
include/asm-i386/apicdef.h
include/asm-i386/mach-generic/mach_apic.h
include/asm-i386/mpspec.h
@@ -833,6 +833,9 @@
 		if (!error) {
 			acpi_lapic = 1;
  
+#ifdef CONFIG_X86_GENERICARCH
+			generic_bigsmp_probe();
+#endif
 			/*
 			 * Parse MADT IO-APIC entries
 			 */
@@ -65,6 +65,8 @@
 int pic_mode;
 unsigned long mp_lapic_addr;
  
+unsigned int def_to_bigsmp = 0;
+
 /* Processor that is doing the boot up */
 unsigned int boot_cpu_physical_apicid = -1U;
 /* Internal processor count */
@@ -213,6 +215,13 @@
 		ver = 0x10;
 	}
 	apic_version[m->mpc_apicid] = ver;
+	if ((num_processors > 8) &&
+	    APIC_XAPIC(ver) &&
+	    (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL))
+		def_to_bigsmp = 1;
+	else
+		def_to_bigsmp = 0;
+
 	bios_cpu_apicid[num_processors - 1] = m->mpc_apicid;
 }
  
@@ -1585,8 +1585,14 @@
 	 */
 	acpi_boot_table_init();
 	acpi_boot_init();
-#endif
  
+#if defined(CONFIG_SMP) && defined(CONFIG_X86_PC)
+	if (def_to_bigsmp)
+		printk(KERN_WARNING "More than 8 CPUs detected and "
+			"CONFIG_X86_PC cannot handle it.\nUse "
+			"CONFIG_X86_GENERICARCH or CONFIG_X86_BIGSMP.\n");
+#endif
+#endif
 #ifdef CONFIG_X86_LOCAL_APIC
 	if (smp_found_config)
 		get_smp_config();
@@ -47,7 +47,10 @@
  
 static __init int probe_bigsmp(void)
 { 
-	dmi_check_system(bigsmp_dmi_table);
+	if (def_to_bigsmp)
+        	dmi_bigsmp = 1;
+	else
+		dmi_check_system(bigsmp_dmi_table);
 	return dmi_bigsmp; 
 } 
  
@@ -30,6 +30,25 @@
 	NULL,
 };
  
+static int cmdline_apic;
+
+void __init generic_bigsmp_probe(void)
+{
+	/*
+	 * This routine is used to switch to bigsmp mode when
+	 * - There is no apic= option specified by the user
+	 * - generic_apic_probe() has choosen apic_default as the sub_arch
+	 * - we find more than 8 CPUs in acpi LAPIC listing with xAPIC support
+	 */
+
+	if (!cmdline_apic && genapic == &apic_default)
+		if (apic_bigsmp.probe()) {
+			genapic = &apic_bigsmp;
+			printk(KERN_INFO "Overriding APIC driver with %s\n",
+			       genapic->name);
+		}
+}
+
 void __init generic_apic_probe(char *command_line) 
 { 
 	char *s;
@@ -52,6 +71,7 @@
 		if (!changed)
 			printk(KERN_ERR "Unknown genapic `%s' specified.\n", s);
 		*p = old;
+		cmdline_apic = changed;
 	} 
 	for (i = 0; !changed && apic_probe[i]; i++) { 
 		if (apic_probe[i]->probe()) {
@@ -16,6 +16,7 @@
 #define			GET_APIC_VERSION(x)	((x)&0xFF)
 #define			GET_APIC_MAXLVT(x)	(((x)>>16)&0xFF)
 #define			APIC_INTEGRATED(x)	((x)&0xF0)
+#define			APIC_XAPIC(x)		((x) >= 0x14)
 #define		APIC_TASKPRI	0x80
 #define			APIC_TPRI_MASK		0xFF
 #define		APIC_ARBPRI	0x90
@@ -28,5 +28,7 @@
 #define enable_apic_mode (genapic->enable_apic_mode)
 #define phys_pkg_id (genapic->phys_pkg_id)
  
+extern void generic_bigsmp_probe(void);
+
 #endif /* __ASM_MACH_APIC_H */
@@ -11,6 +11,7 @@
 extern int quad_local_to_mp_bus_id [NR_CPUS/4][4];
 extern int mp_bus_id_to_pci_bus [MAX_MP_BUSSES];
  
+extern unsigned int def_to_bigsmp;
 extern unsigned int boot_cpu_physical_apicid;
 extern int smp_found_config;
 extern void find_smp_config (void);
...	...	@@ -833,6 +833,9 @@
833	833	if (!error) {
834	834	acpi_lapic = 1;
835	835
	836	+#ifdef CONFIG_X86_GENERICARCH
	837	+ generic_bigsmp_probe();
	838	+#endif
836	839	/*
837	840	* Parse MADT IO-APIC entries
838	841	*/
...	...	@@ -65,6 +65,8 @@
65	65	int pic_mode;
66	66	unsigned long mp_lapic_addr;
67	67
	68	+unsigned int def_to_bigsmp = 0;
	69	+
68	70	/* Processor that is doing the boot up */
69	71	unsigned int boot_cpu_physical_apicid = -1U;
70	72	/* Internal processor count */
...	...	@@ -213,6 +215,13 @@
213	215	ver = 0x10;
214	216	}
215	217	apic_version[m->mpc_apicid] = ver;
	218	+ if ((num_processors > 8) &&
	219	+ APIC_XAPIC(ver) &&
	220	+ (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL))
	221	+ def_to_bigsmp = 1;
	222	+ else
	223	+ def_to_bigsmp = 0;
	224	+
216	225	bios_cpu_apicid[num_processors - 1] = m->mpc_apicid;
217	226	}
218	227
...	...	@@ -1585,8 +1585,14 @@
1585	1585	*/
1586	1586	acpi_boot_table_init();
1587	1587	acpi_boot_init();
1588		-#endif
1589	1588
	1589	+#if defined(CONFIG_SMP) && defined(CONFIG_X86_PC)
	1590	+ if (def_to_bigsmp)
	1591	+ printk(KERN_WARNING "More than 8 CPUs detected and "
	1592	+ "CONFIG_X86_PC cannot handle it.\nUse "
	1593	+ "CONFIG_X86_GENERICARCH or CONFIG_X86_BIGSMP.\n");
	1594	+#endif
	1595	+#endif
1590	1596	#ifdef CONFIG_X86_LOCAL_APIC
1591	1597	if (smp_found_config)
1592	1598	get_smp_config();
...	...	@@ -47,7 +47,10 @@
47	47
48	48	static __init int probe_bigsmp(void)
49	49	{
50		- dmi_check_system(bigsmp_dmi_table);
	50	+ if (def_to_bigsmp)
	51	+ dmi_bigsmp = 1;
	52	+ else
	53	+ dmi_check_system(bigsmp_dmi_table);
51	54	return dmi_bigsmp;
52	55	}
53	56
...	...	@@ -30,6 +30,25 @@
30	30	NULL,
31	31	};
32	32
	33	+static int cmdline_apic;
	34	+
	35	+void __init generic_bigsmp_probe(void)
	36	+{
	37	+ /*
	38	+ * This routine is used to switch to bigsmp mode when
	39	+ * - There is no apic= option specified by the user
	40	+ * - generic_apic_probe() has choosen apic_default as the sub_arch
	41	+ * - we find more than 8 CPUs in acpi LAPIC listing with xAPIC support
	42	+ */
	43	+
	44	+ if (!cmdline_apic && genapic == &apic_default)
	45	+ if (apic_bigsmp.probe()) {
	46	+ genapic = &apic_bigsmp;
	47	+ printk(KERN_INFO "Overriding APIC driver with %s\n",
	48	+ genapic->name);
	49	+ }
	50	+}
	51	+
33	52	void __init generic_apic_probe(char *command_line)
34	53	{
35	54	char *s;
...	...	@@ -52,6 +71,7 @@
52	71	if (!changed)
53	72	printk(KERN_ERR "Unknown genapic `%s' specified.\n", s);
54	73	*p = old;
	74	+ cmdline_apic = changed;
55	75	}
56	76	for (i = 0; !changed && apic_probe[i]; i++) {
57	77	if (apic_probe[i]->probe()) {
...	...	@@ -16,6 +16,7 @@
16	16	#define GET_APIC_VERSION(x) ((x)&0xFF)
17	17	#define GET_APIC_MAXLVT(x) (((x)>>16)&0xFF)
18	18	#define APIC_INTEGRATED(x) ((x)&0xF0)
	19	+#define APIC_XAPIC(x) ((x) >= 0x14)
19	20	#define APIC_TASKPRI 0x80
20	21	#define APIC_TPRI_MASK 0xFF
21	22	#define APIC_ARBPRI 0x90
...	...	@@ -28,5 +28,7 @@
28	28	#define enable_apic_mode (genapic->enable_apic_mode)
29	29	#define phys_pkg_id (genapic->phys_pkg_id)
30	30
	31	+extern void generic_bigsmp_probe(void);
	32	+
31	33	#endif /* __ASM_MACH_APIC_H */
...	...	@@ -11,6 +11,7 @@
11	11	extern int quad_local_to_mp_bus_id [NR_CPUS/4][4];
12	12	extern int mp_bus_id_to_pci_bus [MAX_MP_BUSSES];
13	13
	14	+extern unsigned int def_to_bigsmp;
14	15	extern unsigned int boot_cpu_physical_apicid;
15	16	extern int smp_found_config;
16	17	extern void find_smp_config (void);