linux_dsm_epyc7002/include/asm-sparc64/mmu_context.h
David S. Miller a0663a79ad [SPARC64]: Fix TLB context allocation with SMT style shared TLBs.
The context allocation scheme we use depends upon there being a 1<-->1
mapping from cpu to physical TLB for correctness.  Chips like Niagara
break this assumption.

So what we do is notify all cpus with a cross call when the context
version number changes, and if necessary this makes them allocate
a valid context for the address space they are running at the time.

Stress tested with make -j1024, make -j2048, and make -j4096 kernel
builds on a 32-strand, 8 core, T2000 with 16GB of ram.

Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20 01:14:00 -08:00

122 lines
3.3 KiB
C

/* $Id: mmu_context.h,v 1.54 2002/02/09 19:49:31 davem Exp $ */
#ifndef __SPARC64_MMU_CONTEXT_H
#define __SPARC64_MMU_CONTEXT_H
/* Derived heavily from Linus's Alpha/AXP ASN code... */
#ifndef __ASSEMBLY__
#include <linux/spinlock.h>
#include <asm/system.h>
#include <asm/spitfire.h>
static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
{
}
extern spinlock_t ctx_alloc_lock;
extern unsigned long tlb_context_cache;
extern unsigned long mmu_context_bmap[];
extern void get_new_mmu_context(struct mm_struct *mm);
#ifdef CONFIG_SMP
extern void smp_new_mmu_context_version(void);
#else
#define smp_new_mmu_context_version() do { } while (0)
#endif
extern int init_new_context(struct task_struct *tsk, struct mm_struct *mm);
extern void destroy_context(struct mm_struct *mm);
extern void __tsb_context_switch(unsigned long pgd_pa,
unsigned long tsb_reg,
unsigned long tsb_vaddr,
unsigned long tsb_pte,
unsigned long tsb_descr_pa);
static inline void tsb_context_switch(struct mm_struct *mm)
{
__tsb_context_switch(__pa(mm->pgd), mm->context.tsb_reg_val,
mm->context.tsb_map_vaddr,
mm->context.tsb_map_pte,
__pa(&mm->context.tsb_descr));
}
extern void tsb_grow(struct mm_struct *mm, unsigned long mm_rss, gfp_t gfp_flags);
#ifdef CONFIG_SMP
extern void smp_tsb_sync(struct mm_struct *mm);
#else
#define smp_tsb_sync(__mm) do { } while (0)
#endif
/* Set MMU context in the actual hardware. */
#define load_secondary_context(__mm) \
__asm__ __volatile__( \
"\n661: stxa %0, [%1] %2\n" \
" .section .sun4v_1insn_patch, \"ax\"\n" \
" .word 661b\n" \
" stxa %0, [%1] %3\n" \
" .previous\n" \
" flush %%g6\n" \
: /* No outputs */ \
: "r" (CTX_HWBITS((__mm)->context)), \
"r" (SECONDARY_CONTEXT), "i" (ASI_DMMU), "i" (ASI_MMU))
extern void __flush_tlb_mm(unsigned long, unsigned long);
/* Switch the current MM context. Interrupts are disabled. */
static inline void switch_mm(struct mm_struct *old_mm, struct mm_struct *mm, struct task_struct *tsk)
{
unsigned long ctx_valid;
int cpu;
spin_lock(&mm->context.lock);
ctx_valid = CTX_VALID(mm->context);
if (!ctx_valid)
get_new_mmu_context(mm);
spin_unlock(&mm->context.lock);
if (!ctx_valid || (old_mm != mm)) {
load_secondary_context(mm);
tsb_context_switch(mm);
}
/* Even if (mm == old_mm) we _must_ check
* the cpu_vm_mask. If we do not we could
* corrupt the TLB state because of how
* smp_flush_tlb_{page,range,mm} on sparc64
* and lazy tlb switches work. -DaveM
*/
cpu = smp_processor_id();
if (!ctx_valid || !cpu_isset(cpu, mm->cpu_vm_mask)) {
cpu_set(cpu, mm->cpu_vm_mask);
__flush_tlb_mm(CTX_HWBITS(mm->context),
SECONDARY_CONTEXT);
}
}
#define deactivate_mm(tsk,mm) do { } while (0)
/* Activate a new MM instance for the current task. */
static inline void activate_mm(struct mm_struct *active_mm, struct mm_struct *mm)
{
unsigned long flags;
int cpu;
spin_lock_irqsave(&mm->context.lock, flags);
if (!CTX_VALID(mm->context))
get_new_mmu_context(mm);
cpu = smp_processor_id();
if (!cpu_isset(cpu, mm->cpu_vm_mask))
cpu_set(cpu, mm->cpu_vm_mask);
spin_unlock_irqrestore(&mm->context.lock, flags);
load_secondary_context(mm);
__flush_tlb_mm(CTX_HWBITS(mm->context), SECONDARY_CONTEXT);
tsb_context_switch(mm);
}
#endif /* !(__ASSEMBLY__) */
#endif /* !(__SPARC64_MMU_CONTEXT_H) */