sync: implement pool.work_on_items to process a list of items in parallel

vlib/compiler/tests/repl/repl_test.v

@@ -3,7 +3,6 @@ module main
 import os
 import compiler.tests.repl.runner
 import benchmark
-import runtime
 import sync
 import filepath
 
@@ -28,77 +27,65 @@ fn test_the_v_compiler_can_be_invoked() {
 
 struct Session {
 mut:
-	options   runner.RunnerOptions
-	bmark     benchmark.Benchmark
-	ntask     int
-	ntask_mtx &sync.Mutex
-	waitgroup &sync.WaitGroup
+	options runner.RunnerOptions
+	bmark   benchmark.Benchmark
 }
 
 fn test_all_v_repl_files() {
 	mut session := &Session{
 		options: runner.new_options()
 		bmark: benchmark.new_benchmark()
-		ntask: 0
-		ntask_mtx: sync.new_mutex()
-		waitgroup: sync.new_waitgroup()
 	}
 	// warmup, and ensure that the vrepl is compiled in single threaded mode if it does not exist
 	runner.run_repl_file(os.cachedir(), session.options.vexec, 'vlib/compiler/tests/repl/nothing.repl') or {
 		panic(err)
 	}
-
-	session.bmark.set_total_expected_steps( session.options.files.len )
-	mut ncpus := 0
-	ncpus = runtime.nr_cpus()
+	session.bmark.set_total_expected_steps(session.options.files.len)
+	mut pool_repl := sync.new_pool_processor({
+		callback: worker_repl
+	})
+	pool_repl.set_shared_context(session)
 	$if windows {
-	// See: https://docs.microsoft.com/en-us/cpp/build/reference/fs-force-synchronous-pdb-writes?view=vs-2019
-		ncpus = 1
+		// See: https://docs.microsoft.com/en-us/cpp/build/reference/fs-force-synchronous-pdb-writes?view=vs-2019
+		pool_repl.set_max_jobs(1)
 	}
-	session.waitgroup.add( ncpus )
-	for i:=0; i < ncpus; i++ {
-		go process_in_thread(session,i)
-	}
-	session.waitgroup.wait()
+	pool_repl.work_on_items<string>(session.options.files)
 	session.bmark.stop()
 	println(session.bmark.total_message('total time spent running REPL files'))
 }
 
-fn process_in_thread( session mut Session, thread_id int ){
+fn worker_repl(p mut sync.PoolProcessor, idx int, thread_id int) voidptr {
 	cdir := os.cachedir()
-	mut tls_bench := benchmark.new_benchmark()
-	tls_bench.set_total_expected_steps( session.bmark.nexpected_steps )
-	for {
-		session.ntask_mtx.lock()
-		session.ntask++
-		idx := session.ntask-1
-		session.ntask_mtx.unlock()
-
-		if idx >= session.options.files.len { break }
-		tls_bench.cstep = idx
-
-		tfolder := filepath.join( cdir, 'vrepl_tests_$idx')
-		if os.is_dir( tfolder ) {
-			os.rmdir_all( tfolder )
-		}
-		os.mkdir( tfolder ) or { panic(err) }
-
-		file := session.options.files[ idx ]
-		session.bmark.step()
-		tls_bench.step()
-		fres := runner.run_repl_file(tfolder, session.options.vexec, file) or {
-			session.bmark.fail()
-			tls_bench.fail()
-			os.rmdir_all( tfolder )
-			eprintln(tls_bench.step_message_fail(err))
-			assert false
-			continue
-		}
-		session.bmark.ok()
-		tls_bench.ok()
-		os.rmdir_all( tfolder )
-		println(tls_bench.step_message_ok(fres))
-		assert true
+	mut session := &Session(p.get_shared_context())
+	mut tls_bench := &benchmark.Benchmark(p.get_thread_context(idx))
+	if isnil(tls_bench) {
+		tls_bench = benchmark.new_benchmark_pointer()
+		tls_bench.set_total_expected_steps(session.bmark.nexpected_steps)
+		p.set_thread_context(idx, tls_bench)
 	}
-	session.waitgroup.done()
+	tls_bench.cstep = idx
+	tfolder := filepath.join(cdir,'vrepl_tests_$idx')
+	if os.is_dir(tfolder) {
+		os.rmdir_all(tfolder)
+	}
+	os.mkdir(tfolder) or {
+		panic(err)
+	}
+	file := p.get_string_item(idx)
+	session.bmark.step()
+	tls_bench.step()
+	fres := runner.run_repl_file(tfolder, session.options.vexec, file) or {
+		session.bmark.fail()
+		tls_bench.fail()
+		os.rmdir_all(tfolder)
+		eprintln(tls_bench.step_message_fail(err))
+		assert false
+		return sync.no_result
+	}
+	session.bmark.ok()
+	tls_bench.ok()
+	os.rmdir_all(tfolder)
+	println(tls_bench.step_message_ok(fres))
+	assert true
+	return sync.no_result
 }