diff mbox series

parse: Improve/fix cache invalidation via mtime

Message ID 20240516160515.688850-1-richard.purdie@linuxfoundation.org
State Accepted, archived
Commit d9e5d313c79500e3c70ab9c3239b6b2180194f67
Headers show
Series parse: Improve/fix cache invalidation via mtime | expand

Commit Message

Richard Purdie May 16, 2024, 4:05 p.m. UTC 
We have been seeing obscure failures in devtool, particularly on newer
autobuilder workers where it appears the cache is assumed to be valid
when it shouldn't be.

We're using the 'seconds' granulation mtime field which is not really
a good way of telling if a file has changed. We can switch to the "ns"
version which is better however also add in inode number and size as
precautions. We already have all this data and tuples are fast so there
isn't really any cost to do so.

This hopefully fixes [YOCTO #15318].

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
---
 lib/bb/parse/__init__.py | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)
diff mbox series

Patch

diff --git a/lib/bb/parse/__init__.py b/lib/bb/parse/__init__.py
index a4358f1374..7ffdaa6fd7 100644
--- a/lib/bb/parse/__init__.py
+++ b/lib/bb/parse/__init__.py
@@ -49,20 +49,23 @@  class SkipPackage(SkipRecipe):
 __mtime_cache = {}
 def cached_mtime(f):
     if f not in __mtime_cache:
-        __mtime_cache[f] = os.stat(f)[stat.ST_MTIME]
+        res = os.stat(f)
+        __mtime_cache[f] = (res.st_mtime_ns, res.st_size, res.st_ino)
     return __mtime_cache[f]
 
 def cached_mtime_noerror(f):
     if f not in __mtime_cache:
         try:
-            __mtime_cache[f] = os.stat(f)[stat.ST_MTIME]
+            res = os.stat(f)
+            __mtime_cache[f] = (res.st_mtime_ns, res.st_size, res.st_ino)
         except OSError:
             return 0
     return __mtime_cache[f]
 
 def check_mtime(f, mtime):
     try:
-        current_mtime = os.stat(f)[stat.ST_MTIME]
+        res = os.stat(f)
+        current_mtime = (res.st_mtime_ns, res.st_size, res.st_ino)
         __mtime_cache[f] = current_mtime
     except OSError:
         current_mtime = 0
@@ -70,7 +73,8 @@  def check_mtime(f, mtime):
 
 def update_mtime(f):
     try:
-        __mtime_cache[f] = os.stat(f)[stat.ST_MTIME]
+        res = os.stat(f)
+        __mtime_cache[f] = (res.st_mtime_ns, res.st_size, res.st_ino)
     except OSError:
         if f in __mtime_cache:
             del __mtime_cache[f]