sched: using dst_rq instead of this_rq during load balance (78feefc5) · Commits · 戴 / test

As we already have dst_rq in lb_env, using or changing "this_rq" do not make sense. This patch will replace "this_rq" with dst_rq in load_balance, and we don't need to change "this_rq" while process LBF_SOME_PINNED any more. Signed-off-by:

Michael Wang <wangyun@linux.vnet.ibm.com> Signed-off-by:

Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/501F8357.3070102@linux.vnet.ibm.com Signed-off-by:

Thomas Gleixner <tglx@linutronix.de>

kernel/sched/fair.c

+4 −5

Original line number	Diff line number	Diff line
		@@ -4283,7 +4283,7 @@ redo:
		goto out_balanced;
		}

		BUG_ON(busiest == this_rq);
		BUG_ON(busiest == env.dst_rq);

		schedstat_add(sd, lb_imbalance[idle], env.imbalance);

		@@ -4304,7 +4304,7 @@ redo:
		update_h_load(env.src_cpu);
		more_balance:
		local_irq_save(flags);
		double_rq_lock(this_rq, busiest);
		double_rq_lock(env.dst_rq, busiest);

		/*
		* cur_ld_moved - load moved in current iteration
		@@ -4312,7 +4312,7 @@ more_balance:
		*/
		cur_ld_moved = move_tasks(&env);
		ld_moved += cur_ld_moved;
		double_rq_unlock(this_rq, busiest);
		double_rq_unlock(env.dst_rq, busiest);
		local_irq_restore(flags);

		if (env.flags & LBF_NEED_BREAK) {
		@@ -4348,8 +4348,7 @@ more_balance:
		if ((env.flags & LBF_SOME_PINNED) && env.imbalance > 0 &&
		lb_iterations++ < max_lb_iterations) {

		this_rq = cpu_rq(env.new_dst_cpu);
		env.dst_rq = this_rq;
		env.dst_rq = cpu_rq(env.new_dst_cpu);
		env.dst_cpu = env.new_dst_cpu;
		env.flags &= ~LBF_SOME_PINNED;
		env.loop = 0;

Admin message