diff options
| author | Andy Lutomirski <luto@kernel.org> | 2017-05-28 10:00:14 -0700 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2017-06-05 09:59:44 +0200 |
| commit | ce4a4e565f5264909a18c733b864c3f74467f69e (patch) | |
| tree | d795fc0ca4e922ca10a57c0ac835cd5f005892ee /arch/x86/mm/tlb.c | |
| parent | 3f79e4c7c9c2f5c30751ea5c8dd9fd1d56b81947 (diff) | |
x86/mm: Remove the UP asm/tlbflush.h code, always use the (formerly) SMP code
The UP asm/tlbflush.h generates somewhat nicer code than the SMP version.
Aside from that, it's fallen quite a bit behind the SMP code:
- flush_tlb_mm_range() didn't flush individual pages if the range
was small.
- The lazy TLB code was much weaker. This usually wouldn't matter,
but, if a kernel thread flushed its lazy "active_mm" more than
once (due to reclaim or similar), it wouldn't be unlazied and
would instead pointlessly flush repeatedly.
- Tracepoints were missing.
Aside from that, simply having the UP code around was a maintanence
burden, since it means that any change to the TLB flush code had to
make sure not to break it.
Simplify everything by deleting the UP code.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Nadav Amit <nadav.amit@gmail.com>
Cc: Nadav Amit <namit@vmware.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/mm/tlb.c')
| -rw-r--r-- | arch/x86/mm/tlb.c | 17 |
1 files changed, 2 insertions, 15 deletions
diff --git a/arch/x86/mm/tlb.c b/arch/x86/mm/tlb.c index c03b4a0ce58c..da1416c77bfb 100644 --- a/arch/x86/mm/tlb.c +++ b/arch/x86/mm/tlb.c @@ -15,7 +15,7 @@ #include <linux/debugfs.h> /* - * Smarter SMP flushing macros. + * TLB flushing, formerly SMP-only * c/o Linus Torvalds. * * These mean you can really definitely utterly forget about @@ -28,8 +28,6 @@ * Implement flush IPI by CALL_FUNCTION_VECTOR, Alex Shi */ -#ifdef CONFIG_SMP - /* * We cannot call mmdrop() because we are in interrupt context, * instead update mm->cpu_vm_mask. @@ -53,8 +51,6 @@ void leave_mm(int cpu) } EXPORT_SYMBOL_GPL(leave_mm); -#endif /* CONFIG_SMP */ - void switch_mm(struct mm_struct *prev, struct mm_struct *next, struct task_struct *tsk) { @@ -85,10 +81,8 @@ void switch_mm_irqs_off(struct mm_struct *prev, struct mm_struct *next, set_pgd(pgd, init_mm.pgd[stack_pgd_index]); } -#ifdef CONFIG_SMP this_cpu_write(cpu_tlbstate.state, TLBSTATE_OK); this_cpu_write(cpu_tlbstate.active_mm, next); -#endif cpumask_set_cpu(cpu, mm_cpumask(next)); @@ -146,9 +140,7 @@ void switch_mm_irqs_off(struct mm_struct *prev, struct mm_struct *next, if (unlikely(prev->context.ldt != next->context.ldt)) load_mm_ldt(next); #endif - } -#ifdef CONFIG_SMP - else { + } else { this_cpu_write(cpu_tlbstate.state, TLBSTATE_OK); BUG_ON(this_cpu_read(cpu_tlbstate.active_mm) != next); @@ -175,11 +167,8 @@ void switch_mm_irqs_off(struct mm_struct *prev, struct mm_struct *next, load_mm_ldt(next); } } -#endif } -#ifdef CONFIG_SMP - /* * The flush IPI assumes that a thread switch happens in this order: * [cpu0: the cpu that switches] @@ -436,5 +425,3 @@ static int __init create_tlb_single_page_flush_ceiling(void) return 0; } late_initcall(create_tlb_single_page_flush_ceiling); - -#endif /* CONFIG_SMP */ |