[PATCH 4/4] patman: Check patches in parallel

[Simon Glass]

For large series this can take a while. Run checkpatch in parallel to
try to reduce the time. The checkpatch information is still reported in
sequential order, so a very slow patch at the start can still slow
things down. But overall this gives good results.

Signed-off-by: Simon Glass <sjg at chromium.org>
---

 tools/patmanu/checkpatch.py | 46 +++++++++++++++++++++----------------
 1 file changed, 26 insertions(+), 20 deletions(-)

diff --git a/tools/patmanu/checkpatch.py b/tools/patmanu/checkpatch.py
index 55d962f536f..1317f50b464 100644
--- a/tools/patmanu/checkpatch.py
+++ b/tools/patmanu/checkpatch.py
@@ -3,6 +3,7 @@
 #
 
 import collections
+import concurrent.futures
 import os
 import re
 import sys
@@ -244,26 +245,31 @@ def check_patches(verbose, args, use_tree):
     error_count, warning_count, check_count = 0, 0, 0
     col = terminal.Color()
 
-    for fname in args:
-        result = check_patch(fname, verbose, use_tree=use_tree)
-        if not result.ok:
-            error_count += result.errors
-            warning_count += result.warnings
-            check_count += result.checks
-            print('%d errors, %d warnings, %d checks for %s:' % (result.errors,
-                    result.warnings, result.checks, col.build(col.BLUE, fname)))
-            if (len(result.problems) != result.errors + result.warnings +
-                    result.checks):
-                print("Internal error: some problems lost")
-            # Python seems to get confused by this
-            # pylint: disable=E1133
-            for item in result.problems:
-                sys.stderr.write(
-                    get_warning_msg(col, item.get('type', '<unknown>'),
-                        item.get('file', '<unknown>'),
-                        item.get('line', 0), item.get('msg', 'message')))
-            print
-            #print(stdout)
+    with concurrent.futures.ThreadPoolExecutor(max_workers=16) as executor:
+        futures = []
+        for fname in args:
+            f = executor.submit(check_patch, fname, verbose, use_tree=use_tree)
+            futures.append(f)
+
+        for fname, f in zip(args, futures):
+            result = f.result()
+            if not result.ok:
+                error_count += result.errors
+                warning_count += result.warnings
+                check_count += result.checks
+                print('%d errors, %d warnings, %d checks for %s:' % (result.errors,
+                        result.warnings, result.checks, col.build(col.BLUE, fname)))
+                if (len(result.problems) != result.errors + result.warnings +
+                        result.checks):
+                    print("Internal error: some problems lost")
+                # Python seems to get confused by this
+                # pylint: disable=E1133
+                for item in result.problems:
+                    sys.stderr.write(
+                        get_warning_msg(col, item.get('type', '<unknown>'),
+                            item.get('file', '<unknown>'),
+                            item.get('line', 0), item.get('msg', 'message')))
+                print
     if error_count or warning_count or check_count:
         str = 'checkpatch.pl found %d error(s), %d warning(s), %d checks(s)'
         color = col.GREEN
-- 
2.39.2.637.g21b0678d19-goog