diff options
| author | David S. Miller <davem@davemloft.net> | 2006-02-23 14:19:28 -0800 |
|---|---|---|
| committer | David S. Miller <davem@sunset.davemloft.net> | 2006-03-20 01:14:00 -0800 |
| commit | a0663a79ad4faebe1db4a56e2e767b120b12333a (patch) | |
| tree | 612a53e387a6aea6116f8a1637050fa13c6d9f80 /arch/sparc64/mm/init.c | |
| parent | 074d82cf688fe2dfa7ba4a2317c56f62d13fb522 (diff) | |
[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>
Diffstat (limited to 'arch/sparc64/mm/init.c')
| -rw-r--r-- | arch/sparc64/mm/init.c | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/arch/sparc64/mm/init.c b/arch/sparc64/mm/init.c index 16f0db38d93..ccf083aecb6 100644 --- a/arch/sparc64/mm/init.c +++ b/arch/sparc64/mm/init.c @@ -629,17 +629,20 @@ void __flush_dcache_range(unsigned long start, unsigned long end) * let the user have CTX 0 (nucleus) or we ever use a CTX * version of zero (and thus NO_CONTEXT would not be caught * by version mis-match tests in mmu_context.h). + * + * Always invoked with interrupts disabled. */ void get_new_mmu_context(struct mm_struct *mm) { unsigned long ctx, new_ctx; unsigned long orig_pgsz_bits; - + int new_version; spin_lock(&ctx_alloc_lock); orig_pgsz_bits = (mm->context.sparc64_ctx_val & CTX_PGSZ_MASK); ctx = (tlb_context_cache + 1) & CTX_NR_MASK; new_ctx = find_next_zero_bit(mmu_context_bmap, 1 << CTX_NR_BITS, ctx); + new_version = 0; if (new_ctx >= (1 << CTX_NR_BITS)) { new_ctx = find_next_zero_bit(mmu_context_bmap, ctx, 1); if (new_ctx >= ctx) { @@ -662,6 +665,7 @@ void get_new_mmu_context(struct mm_struct *mm) mmu_context_bmap[i + 2] = 0; mmu_context_bmap[i + 3] = 0; } + new_version = 1; goto out; } } @@ -671,6 +675,9 @@ out: tlb_context_cache = new_ctx; mm->context.sparc64_ctx_val = new_ctx | orig_pgsz_bits; spin_unlock(&ctx_alloc_lock); + + if (unlikely(new_version)) + smp_new_mmu_context_version(); } void sparc_ultra_dump_itlb(void) |