x86/mm/tlb.c

1108 	 * - mm_tlb_gen:     the latest generation.
1120 	u64 mm_tlb_gen;
1173 		 * While the core might be still behind mm_tlb_gen, checking
1174 		 * mm_tlb_gen unnecessarily would have negative caching effects
1181 	 * Defer mm_tlb_gen reading as long as possible to avoid cache
1184 	mm_tlb_gen = atomic64_read(&loaded_mm->context.tlb_gen);
1186 	if (unlikely(local_tlb_gen == mm_tlb_gen)) {
1196 	WARN_ON_ONCE(local_tlb_gen > mm_tlb_gen);
1197 	WARN_ON_ONCE(f->new_tlb_gen > mm_tlb_gen);
1223 	 *     local_tlb_gen == 1, mm_tlb_gen == 3, and end != TLB_FLUSH_ALL.
1228 	 * 2. f->new_tlb_gen == mm_tlb_gen.  This is purely an optimization.
1233 	 *    local_tlb_gen all the way to mm_tlb_gen and we can probably
1238 	    f->new_tlb_gen == mm_tlb_gen) {
1265 	/* Both paths above update our state to mm_tlb_gen. */
1266 	this_cpu_write(cpu_tlbstate.ctxs[loaded_mm_asid].tlb_gen, mm_tlb_gen);