If the system has more than 8 CPUs then XAPIC and the bigsmp APIC driver is
required. This is ensured via:
1) Enumerating all possible CPUs up to NR_CPUS
2) Checking at boot CPU APIC setup time whether the system has more than
8 CPUs and has an XAPIC.
If that's the case then it's attempted to install the bigsmp APIC
driver and a magic variable 'def_to_bigsmp' is set to one.
3) If that magic variable is set and CONFIG_X86_BIGSMP=n and the system
has more than 8 CPUs smp_sanity_check() removes all CPUs >= #8 from
the present and possible mask in the most convoluted way.
This logic is completely broken for the case where the bigsmp driver is
enabled, but not selected due to a command line option specifying the
default APIC. In that case the system boots with default APIC in logical
destination mode and fails to reduce the number of CPUs.
That aside the above which is sprinkled over 3 different places is yet
another piece of art.
It would have been too obvious to check the requirements upfront and limit
nr_cpu_ids _before_ enumerating tons of CPUs and then removing them again.
Implement exactly this. Check the bigsmp requirement when the boot APIC is
registered which happens _before_ ACPI/MPTABLE parsing and limit the number
of CPUs to 8 if it can't be used. Switch it over when the boot CPU apic is
set up if necessary.
[ dhansen: fix nr_cpu_ids off-by-one in default_setup_apic_routing() ]
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Michael Kelley <mikelley@microsoft.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Juergen Gross <jgross@suse.com> # Xen PV (dom0 and unpriv. guest)
116 lines
2.7 KiB
C
116 lines
2.7 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
#ifndef _ASM_X86_MPSPEC_H
|
|
#define _ASM_X86_MPSPEC_H
|
|
|
|
|
|
#include <asm/mpspec_def.h>
|
|
#include <asm/x86_init.h>
|
|
#include <asm/apicdef.h>
|
|
|
|
extern int pic_mode;
|
|
|
|
#ifdef CONFIG_X86_32
|
|
|
|
/*
|
|
* Summit or generic (i.e. installer) kernels need lots of bus entries.
|
|
* Maximum 256 PCI busses, plus 1 ISA bus in each of 4 cabinets.
|
|
*/
|
|
#if CONFIG_BASE_SMALL == 0
|
|
# define MAX_MP_BUSSES 260
|
|
#else
|
|
# define MAX_MP_BUSSES 32
|
|
#endif
|
|
|
|
#define MAX_IRQ_SOURCES 256
|
|
|
|
#else /* CONFIG_X86_64: */
|
|
|
|
#define MAX_MP_BUSSES 256
|
|
/* Each PCI slot may be a combo card with its own bus. 4 IRQ pins per slot. */
|
|
#define MAX_IRQ_SOURCES (MAX_MP_BUSSES * 4)
|
|
|
|
#endif /* CONFIG_X86_64 */
|
|
|
|
#ifdef CONFIG_EISA
|
|
extern int mp_bus_id_to_type[MAX_MP_BUSSES];
|
|
#endif
|
|
|
|
extern DECLARE_BITMAP(mp_bus_not_pci, MAX_MP_BUSSES);
|
|
|
|
extern unsigned int boot_cpu_physical_apicid;
|
|
extern u8 boot_cpu_apic_version;
|
|
|
|
#ifdef CONFIG_X86_LOCAL_APIC
|
|
extern int smp_found_config;
|
|
#else
|
|
# define smp_found_config 0
|
|
#endif
|
|
|
|
static inline void get_smp_config(void)
|
|
{
|
|
x86_init.mpparse.get_smp_config(0);
|
|
}
|
|
|
|
static inline void early_get_smp_config(void)
|
|
{
|
|
x86_init.mpparse.get_smp_config(1);
|
|
}
|
|
|
|
static inline void find_smp_config(void)
|
|
{
|
|
x86_init.mpparse.find_smp_config();
|
|
}
|
|
|
|
#ifdef CONFIG_X86_MPPARSE
|
|
extern void e820__memblock_alloc_reserved_mpc_new(void);
|
|
extern int enable_update_mptable;
|
|
extern void default_find_smp_config(void);
|
|
extern void default_get_smp_config(unsigned int early);
|
|
#else
|
|
static inline void e820__memblock_alloc_reserved_mpc_new(void) { }
|
|
#define enable_update_mptable 0
|
|
#define default_find_smp_config x86_init_noop
|
|
#define default_get_smp_config x86_init_uint_noop
|
|
#endif
|
|
|
|
int generic_processor_info(int apicid);
|
|
|
|
#define PHYSID_ARRAY_SIZE BITS_TO_LONGS(MAX_LOCAL_APIC)
|
|
|
|
struct physid_mask {
|
|
unsigned long mask[PHYSID_ARRAY_SIZE];
|
|
};
|
|
|
|
typedef struct physid_mask physid_mask_t;
|
|
|
|
#define physid_set(physid, map) set_bit(physid, (map).mask)
|
|
#define physid_isset(physid, map) test_bit(physid, (map).mask)
|
|
|
|
#define physids_or(dst, src1, src2) \
|
|
bitmap_or((dst).mask, (src1).mask, (src2).mask, MAX_LOCAL_APIC)
|
|
|
|
#define physids_clear(map) \
|
|
bitmap_zero((map).mask, MAX_LOCAL_APIC)
|
|
|
|
#define physids_empty(map) \
|
|
bitmap_empty((map).mask, MAX_LOCAL_APIC)
|
|
|
|
static inline void physids_promote(unsigned long physids, physid_mask_t *map)
|
|
{
|
|
physids_clear(*map);
|
|
map->mask[0] = physids;
|
|
}
|
|
|
|
static inline void physid_set_mask_of_physid(int physid, physid_mask_t *map)
|
|
{
|
|
physids_clear(*map);
|
|
physid_set(physid, *map);
|
|
}
|
|
|
|
#define PHYSID_MASK_ALL { {[0 ... PHYSID_ARRAY_SIZE-1] = ~0UL} }
|
|
#define PHYSID_MASK_NONE { {[0 ... PHYSID_ARRAY_SIZE-1] = 0UL} }
|
|
|
|
extern physid_mask_t phys_cpu_present_map;
|
|
|
|
#endif /* _ASM_X86_MPSPEC_H */
|