From: Jaya Prakash <jayaprakash@ibm.com>
Date: Wed, 26 Feb 2025 14:02:59 +0000 (+0530)
Subject: blk/kernel : skip AIO thread for zero-sized devices
X-Git-Tag: v20.3.0~442^2
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=481dfb15e4675eecacae401500a8e5c555948314;p=ceph.git

blk/kernel : skip AIO thread for zero-sized devices

Sometimes devices can be 0-sized, where I/O is impossible.

This change skips _aio_start() in open() if the device size is 0. This avoids unnecessary AIO setup.

This issue was introduced in PR : https://github.com/ceph/ceph/pull/60791

Signed-off-by: Jaya Prakash <jayaprakash@ibm.com>
---

diff --git a/src/blk/kernel/KernelDevice.cc b/src/blk/kernel/KernelDevice.cc
index 41f0608355dd..c4e6168a61dd 100644
--- a/src/blk/kernel/KernelDevice.cc
+++ b/src/blk/kernel/KernelDevice.cc
@@ -295,9 +295,13 @@ int KernelDevice::open(const string& p)
     goto out_fail;
   }
 
-  r = _aio_start();
-  if (r < 0) {
-    goto out_fail;
+  if (size > 0) {
+    r = _aio_start();
+    if (r < 0) {
+      goto out_fail;
+    }
+  } else {
+    aio = false;
   }
 
   _discard_update_threads();