linux/arch/ia64/include/asm/smp.h
David Howells 9b8de7479d FRV: Fix the section attribute on UP DECLARE_PER_CPU()
In non-SMP mode, the variable section attribute specified by DECLARE_PER_CPU()
does not agree with that specified by DEFINE_PER_CPU().  This means that
architectures that have a small data section references relative to a base
register may throw up linkage errors due to too great a displacement between
where the base register points and the per-CPU variable.

On FRV, the .h declaration says that the variable is in the .sdata section, but
the .c definition says it's actually in the .data section.  The linker throws
up the following errors:

kernel/built-in.o: In function `release_task':
kernel/exit.c:78: relocation truncated to fit: R_FRV_GPREL12 against symbol `per_cpu__process_counts' defined in .data section in kernel/built-in.o
kernel/exit.c:78: relocation truncated to fit: R_FRV_GPREL12 against symbol `per_cpu__process_counts' defined in .data section in kernel/built-in.o

To fix this, DECLARE_PER_CPU() should simply apply the same section attribute
as does DEFINE_PER_CPU().  However, this is made slightly more complex by
virtue of the fact that there are several variants on DEFINE, so these need to
be matched by variants on DECLARE.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-21 19:39:59 -07:00

139 lines
3.3 KiB
C

/*
* SMP Support
*
* Copyright (C) 1999 VA Linux Systems
* Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
* (c) Copyright 2001-2003, 2005 Hewlett-Packard Development Company, L.P.
* David Mosberger-Tang <davidm@hpl.hp.com>
* Bjorn Helgaas <bjorn.helgaas@hp.com>
*/
#ifndef _ASM_IA64_SMP_H
#define _ASM_IA64_SMP_H
#include <linux/init.h>
#include <linux/threads.h>
#include <linux/kernel.h>
#include <linux/cpumask.h>
#include <linux/bitops.h>
#include <linux/irqreturn.h>
#include <asm/io.h>
#include <asm/param.h>
#include <asm/processor.h>
#include <asm/ptrace.h>
static inline unsigned int
ia64_get_lid (void)
{
union {
struct {
unsigned long reserved : 16;
unsigned long eid : 8;
unsigned long id : 8;
unsigned long ignored : 32;
} f;
unsigned long bits;
} lid;
lid.bits = ia64_getreg(_IA64_REG_CR_LID);
return lid.f.id << 8 | lid.f.eid;
}
#define hard_smp_processor_id() ia64_get_lid()
#ifdef CONFIG_SMP
#define XTP_OFFSET 0x1e0008
#define SMP_IRQ_REDIRECTION (1 << 0)
#define SMP_IPI_REDIRECTION (1 << 1)
#define raw_smp_processor_id() (current_thread_info()->cpu)
extern struct smp_boot_data {
int cpu_count;
int cpu_phys_id[NR_CPUS];
} smp_boot_data __initdata;
extern char no_int_routing __devinitdata;
extern cpumask_t cpu_core_map[NR_CPUS];
DECLARE_PER_CPU_SHARED_ALIGNED(cpumask_t, cpu_sibling_map);
extern int smp_num_siblings;
extern void __iomem *ipi_base_addr;
extern unsigned char smp_int_redirect;
extern volatile int ia64_cpu_to_sapicid[];
#define cpu_physical_id(i) ia64_cpu_to_sapicid[i]
extern unsigned long ap_wakeup_vector;
/*
* Function to map hard smp processor id to logical id. Slow, so don't use this in
* performance-critical code.
*/
static inline int
cpu_logical_id (int cpuid)
{
int i;
for (i = 0; i < NR_CPUS; ++i)
if (cpu_physical_id(i) == cpuid)
break;
return i;
}
/*
* XTP control functions:
* min_xtp : route all interrupts to this CPU
* normal_xtp: nominal XTP value
* max_xtp : never deliver interrupts to this CPU.
*/
static inline void
min_xtp (void)
{
if (smp_int_redirect & SMP_IRQ_REDIRECTION)
writeb(0x00, ipi_base_addr + XTP_OFFSET); /* XTP to min */
}
static inline void
normal_xtp (void)
{
if (smp_int_redirect & SMP_IRQ_REDIRECTION)
writeb(0x08, ipi_base_addr + XTP_OFFSET); /* XTP normal */
}
static inline void
max_xtp (void)
{
if (smp_int_redirect & SMP_IRQ_REDIRECTION)
writeb(0x0f, ipi_base_addr + XTP_OFFSET); /* Set XTP to max */
}
/* Upping and downing of CPUs */
extern int __cpu_disable (void);
extern void __cpu_die (unsigned int cpu);
extern void cpu_die (void) __attribute__ ((noreturn));
extern void __init smp_build_cpu_map(void);
extern void __init init_smp_config (void);
extern void smp_do_timer (struct pt_regs *regs);
extern irqreturn_t handle_IPI(int irq, void *dev_id);
extern void smp_send_reschedule (int cpu);
extern void identify_siblings (struct cpuinfo_ia64 *);
extern int is_multithreading_enabled(void);
extern void arch_send_call_function_single_ipi(int cpu);
extern void arch_send_call_function_ipi_mask(const struct cpumask *mask);
#define arch_send_call_function_ipi_mask arch_send_call_function_ipi_mask
#else /* CONFIG_SMP */
#define cpu_logical_id(i) 0
#define cpu_physical_id(i) ia64_get_lid()
#endif /* CONFIG_SMP */
#endif /* _ASM_IA64_SMP_H */