diff options
| author | David Fries <david@fries.net> | 2008-10-16 09:04:38 +0400 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2008-10-16 22:21:49 +0400 |
| commit | c30c9b15187e977ab5928f7276e9dfcd8d6f9460 (patch) | |
| tree | d36d7513c5acf1d39f581625ffa5c1915ae5627f /drivers/w1/w1_family.c | |
| parent | dd78c9439fc1e031835bccb934d27b978c72c536 (diff) | |
| download | linux-c30c9b15187e977ab5928f7276e9dfcd8d6f9460.tar.xz | |
W1: fix deadlocks and remove w1_control_thread
w1_control_thread was removed which would wake up every second and process
newly registered family codes and complete some final cleanup for a
removed master. Those routines were moved to the threads that were
previously requesting those operations. A new function
w1_reconnect_slaves takes care of reconnecting existing slave devices when
a new family code is registered or removed. The removal case was missing
and would cause a deadlock waiting for the family code reference count to
decrease, which will now happen. A problem with registering a family code
was fixed. A slave device would be unattached if it wasn't yet claimed,
then attached at the end of the list, two unclaimed slaves would cause an
infinite loop.
The struct w1_bus_master.search now takes a pointer to the struct
w1_master device to avoid searching for it, which would have caused a
lock ordering deadlock with the removal of w1_control_thread.
Signed-off-by: David Fries <david@fries.net>
Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/w1/w1_family.c')
| -rw-r--r-- | drivers/w1/w1_family.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/drivers/w1/w1_family.c b/drivers/w1/w1_family.c index a3c95bd6890a..8c35f9ccb689 100644 --- a/drivers/w1/w1_family.c +++ b/drivers/w1/w1_family.c @@ -53,7 +53,8 @@ int w1_register_family(struct w1_family *newf) } spin_unlock(&w1_flock); - w1_reconnect_slaves(newf); + /* check default devices against the new set of drivers */ + w1_reconnect_slaves(newf, 1); return ret; } @@ -77,6 +78,9 @@ void w1_unregister_family(struct w1_family *fent) spin_unlock(&w1_flock); + /* deatch devices using this family code */ + w1_reconnect_slaves(fent, 0); + while (atomic_read(&fent->refcnt)) { printk(KERN_INFO "Waiting for family %u to become free: refcnt=%d.\n", fent->fid, atomic_read(&fent->refcnt)); |