Changeset 81614543 in mainline

Timestamp:

2007-11-11T13:06:15Z (17 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

7c5bcc0

Parents:

6c4ff8a

Message:

VFS work.
vfs_grab_phone() must disable fibril preemption in order to avoid deadlock with
other fibrils of the same thread that might be trying to vfs_grab_phone() too.

File:

• uspace/srv/vfs/vfs_register.c (modified) (3 diffs)

uspace/srv/vfs/vfs_register.c

@@ -39 +39 @@
 #include <ipc/services.h>
 #include <async.h>
+#include <fibril.h>
 #include <errno.h>
 #include <stdio.h>
@@ -339 +340 @@
                          */
                         futex_down(&fs->phone_futex);
+                        /*
+                         * Avoid deadlock with other fibrils in the same thread
+                         * by disabling fibril preemption.
+                         */
+                        fibril_inc_sercount();
                         return fs->phone; 
                 }
@@ -354 +360 @@
         bool found = false;
 
+        /*
+         * Undo the fibril_inc_sercount() done in vfs_grab_phone().
+         */
+        fibril_dec_sercount();
+        
         futex_down(&fs_head_futex);
         link_t *cur;