Fix mkldnn related irpasses being added triple times

[luotao1]

• fix mkldnn related irpasses are added triple times when mkldnn is enabled in AnaylsisPredictor #16174
• Inspired by pass_builder()->EnableMKLDNN() is called again in Update() after pass_builder reset (see Fix mkldnn related irpasses being added triple times #16175 (comment)).

[sfraczek]

Roughly looking, this could work fine unless a user calls AnalysisConfig::EnableMKLDNN() twice. Now the flag use_mkldnn_ has no use in both:

1. AnalysisConfig - because it is not checked.
2. PassStrategy - because now I think we assume CpuPassStrategy::EnableMKLDNN() is called only once.

[luotao1]

Now the flag use_mkldnn_ has no use in both:

flag use_mkldnn_ would be used in

Paddle/paddle/fluid/inference/api/analysis_predictor.cc

Lines 376 to 379 in c49e604

	if (config_.use_mkldnn_) {
	LOG(INFO) << "MKLDNN is enabled";
	argument_.SetMKLDNNEnabledOpTypes(config_.mkldnn_enabled_op_types_);
	}

[sfraczek]

ok

[LeoZhao-Intel]

with this change, the issue looks like fixed, but it seems to cause status mismatch between Passes_ and use_mkldnn_ in CpuPassStrategy. use_mkldnn_ in old CpuPassStrategy instance was not copied into new one, while Passes_ copied.

Better to add use_mkldnn_ in CpuPassStrategy copy constructor to avoid this mismatch.

[luotao1]

use_mkldnn_ in old CpuPassStrategy instance was not copied into new one, while Passes_ copied

use_mkldnn_ will be copied here.

Paddle/paddle/fluid/inference/api/analysis_config.cc

Line 108 in 7458114

CP_MEMBER(use_mkldnn_);

[tensor-tang]

LGTM.
Need @Superjomn 's double check.

[LeoZhao-Intel]

use_mkldnn_ in old CpuPassStrategy instance was not copied into new one, while Passes_ copied

use_mkldnn_ will be copied here.
Paddle/paddle/fluid/inference/api/analysis_config.cc

Line 108 in 7458114

CP_MEMBER(use_mkldnn_);

I mean use_mkldnn_ in CpuPassStrategy/PassStrategy, instead of AnalysisConfig,

void AnalysisConfig::EnableMKLDNN() {
#ifdef PADDLE_WITH_MKLDNN
  pass_builder()->EnableMKLDNN();
  use_mkldnn_ = true;
#else
  LOG(ERROR) << "Please compile with MKLDNN first to use MKLDNN";
  use_mkldnn_ = false;
#endif

  Update();
}

There are 2 members named use_mkldnn_ , one is AnaysisConfig, the other in PassStrategy.
In Update(), pass_builder_ will be reset with passes_ copied, but in new pass_builder_ instance, use_mkldnn_ value is still false while passes_ has included mkldnn irpasses already, which is what I mean "mismatch". That's why irpasses were added triple times.

with your change, passes_ will not be added again, but use_mkldnn_ in PassStrategy will be false.

[sfraczek]

I agree with @LeoZhao-Intel that the use_mkldnn_ left in the PassStrategy now has no clear purpose and something should be done about it.