somewhere max_execute_time is not properly used when sql hint max_execute_time is set

[jiyfhust]

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. Minimal reproduce step (Required)

For example:

tidb/pkg/planner/core/plan_stats.go

Lines 103 to 112 in 9bad202

	stmtCtx := ctx.GetSessionVars().StmtCtx
	hintMaxExecutionTime := int64(stmtCtx.MaxExecutionTime)
	if hintMaxExecutionTime <= 0 {
	hintMaxExecutionTime = maxDuration
	}
	sessMaxExecutionTime := int64(ctx.GetSessionVars().MaxExecutionTime)
	if sessMaxExecutionTime <= 0 {
	sessMaxExecutionTime = maxDuration
	}
	waitTime := min(syncWait, hintMaxExecutionTime, sessMaxExecutionTime)

if sql hint max_execute_time is set, then session variable max_execute_time should be ignored.

and

tidb/pkg/expression/builtin_info.go

Line 940 in 9bad202

timeout := time.Duration(ctx.GetSessionVars().MaxExecutionTime) * time.Millisecond

:

sql hint max_execute_time is not considered.

2. What did you expect to see? (Required)

3. What did you see instead (Required)

4. What is your TiDB version? (Required)

master

[jiyfhust]

@qw4990 Please table a look the pr for this issue.