Messages in this thread Patch in this message | | | From | Nadav Amit <> | Subject | [PATCH v2 8/9] x86/mm/tlb: Remove UV special case | Date | Tue, 2 Jul 2019 16:51:50 -0700 |
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SGI UV support is outdated and not maintained, and it is not clear how it performs relatively to non-UV. Remove the code to simplify the code.
Cc: Peter Zijlstra <peterz@infradead.org> Cc: Dave Hansen <dave.hansen@intel.com> Suggested-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Nadav Amit <namit@vmware.com> --- arch/x86/mm/tlb.c | 25 ------------------------- 1 file changed, 25 deletions(-)
diff --git a/arch/x86/mm/tlb.c b/arch/x86/mm/tlb.c index b47a71820f35..64afe1215495 100644 --- a/arch/x86/mm/tlb.c +++ b/arch/x86/mm/tlb.c @@ -689,31 +689,6 @@ void native_flush_tlb_multi(const struct cpumask *cpumask, trace_tlb_flush(TLB_REMOTE_SEND_IPI, (info->end - info->start) >> PAGE_SHIFT); - if (is_uv_system()) { - /* - * This whole special case is confused. UV has a "Broadcast - * Assist Unit", which seems to be a fancy way to send IPIs. - * Back when x86 used an explicit TLB flush IPI, UV was - * optimized to use its own mechanism. These days, x86 uses - * smp_call_function_many(), but UV still uses a manual IPI, - * and that IPI's action is out of date -- it does a manual - * flush instead of calling flush_tlb_func_remote(). This - * means that the percpu tlb_gen variables won't be updated - * and we'll do pointless flushes on future context switches. - * - * Rather than hooking native_flush_tlb_multi() here, I think - * that UV should be updated so that smp_call_function_many(), - * etc, are optimal on UV. - */ - flush_tlb_func_local(info); - - cpumask = uv_flush_tlb_others(cpumask, info); - if (cpumask) - smp_call_function_many(cpumask, flush_tlb_func_remote, - (void *)info, 1); - return; - } - /* * If no page tables were freed, we can skip sending IPIs to * CPUs in lazy TLB mode. They will flush the CPU themselves -- 2.17.1
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