[v15,05/11] x86/mm: Use broadcast TLB flushing in page reclaim

Commit Message

Borislav Petkov March 4, 2025, 1:58 p.m. UTC

From: Rik van Riel <[e-mail]>

Page reclaim tracks only the CPU(s) where the TLB needs to be flushed, rather
than all the individual mappings that may be getting invalidated.

Use broadcast TLB flushing when that is available.

  [ bp: Massage commit message. ]

Signed-off-by: Rik van Riel <[e-mail]>
Signed-off-by: Borislav Petkov (AMD) <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
---
 arch/x86/mm/tlb.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

Patch

diff --git a/arch/x86/mm/tlb.c b/arch/x86/mm/tlb.c
index 8cd084bc3d98..76b4a88afb56 100644
--- a/arch/x86/mm/tlb.c
+++ b/arch/x86/mm/tlb.c
@@ -1320,7 +1320,9 @@  void arch_tlbbatch_flush(struct arch_tlbflush_unmap_batch *batch)
 	 * a local TLB flush is needed. Optimize this use-case by calling
 	 * flush_tlb_func_local() directly in this case.
 	 */
-	if (cpumask_any_but(&batch->cpumask, cpu) < nr_cpu_ids) {
+	if (cpu_feature_enabled(X86_FEATURE_INVLPGB)) {
+		invlpgb_flush_all_nonglobals();
+	} else if (cpumask_any_but(&batch->cpumask, cpu) < nr_cpu_ids) {
 		flush_tlb_multi(&batch->cpumask, info);
 	} else if (cpumask_test_cpu(cpu, &batch->cpumask)) {
 		lockdep_assert_irqs_enabled();