Hello,
On 12 August 2006 17:26, Laurent Riffard wrote:
> Le 03.08.2006 17:07, Laurent Riffard a écrit :
> > Le 03.08.2006 08:09, Alexander Zarochentsev a écrit :
> >> On Tuesday 01 August 2006 01:29, Laurent Riffard wrote:
> >>> Le 31.07.2006 21:55, Vladimir V. Saveliev a écrit :
> >>>> Hello
> >>>>
> >>>> What kind of load did you run on reiser4 at that time?
> >>>
> >>> I just formatted a new 2GB Reiser4 FS, then I moved a whole
> >>> ccache cache tree to this new FS (cache size was about 20~30
> >>> Mbytes). Something like:
> >>>
> >>> # mkfs.reiser4 /dev/vglinux1/ccache
> >>> # mount -tauto -onoatime /dev/vglinux1/ccache /mnt/disk
> >>> # mv ~laurent/.ccache/* /mnt/disk/
> >>
> >> I was not able to reproduce it. Can you please try the following
> >> patch?
> >>
> >>
> >> lock validator friendly locking of new atom in
> >> atom_begin_and_assign_to_txnh and locking of two atoms.
> >>
> >> Signed-off-by: Alexander Zarochentsev <[EMAIL PROTECTED]>
> >> ---
> >>
> >> fs/reiser4/txnmgr.c | 14 ++++++++------
> >> fs/reiser4/txnmgr.h | 15 +++++++++++++++
> >> 2 files changed, 23 insertions(+), 6 deletions(-)
>
> [patch snipped]
>
> > I tried this patch: it's slow as hell (CPU is ~100% system) and it
overhead of locking dependency checks?
also disabling CONFIG_REISER4_DEBUG should help tp reduce cpu usage.
> > panics when syncing...
please apply another patch
lock validator friendly locking of new atom in
atom_begin_and_assign_to_txnh and locking of two atoms.
Signed-off-by: Alexander Zarochentsev <[EMAIL PROTECTED]>
---
fs/reiser4/txnmgr.c | 14 ++++++++------
fs/reiser4/txnmgr.h | 15 +++++++++++++++
2 files changed, 23 insertions(+), 6 deletions(-)
--- linux-2.6-git.orig/fs/reiser4/txnmgr.c
+++ linux-2.6-git/fs/reiser4/txnmgr.c
@@ -397,7 +397,7 @@ static void atom_init(txn_atom * atom)
INIT_LIST_HEAD(ATOM_OVRWR_LIST(atom));
INIT_LIST_HEAD(ATOM_WB_LIST(atom));
INIT_LIST_HEAD(&atom->inodes);
- spin_lock_init(&atom->alock);
+ spin_lock_init(&(atom->alock));
/* list of transaction handles */
INIT_LIST_HEAD(&atom->txnh_list);
/* link to transaction manager's list of atoms */
@@ -732,10 +732,12 @@ static int atom_begin_and_assign_to_txnh
assert("jmacd-17", atom_isclean(atom));
/*
- * do not use spin_lock_atom because we have broken lock ordering here
- * which is ok, as long as @atom is new and inaccessible for others.
+ * lock ordering is broken here. It is ok, as long as @atom is new
+ * and inaccessible for others. We can't use spin_lock_atom or
+ * spin_lock(&atom->alock) because they care about locking
+ * dependencies. spin_trylock_lock doesn't.
*/
- spin_lock(&(atom->alock));
+ check_me("", spin_trylock_atom(atom));
/* add atom to the end of transaction manager's list of atoms */
list_add_tail(&atom->atom_link, &mgr->atoms_list);
@@ -751,7 +753,7 @@ static int atom_begin_and_assign_to_txnh
atom->super = reiser4_get_current_sb();
capture_assign_txnh_nolock(atom, txnh);
- spin_unlock(&(atom->alock));
+ spin_unlock_atom(atom);
spin_unlock_txnh(txnh);
return -E_REPEAT;
@@ -2112,11 +2114,11 @@ static void fuse_not_fused_lock_owners(t
atomic_inc(&atomf->refcount);
spin_unlock_txnh(ctx->trans);
if (atomf > atomh) {
- spin_lock_atom(atomf);
+ spin_lock_atom_nested(atomf);
} else {
spin_unlock_atom(atomh);
spin_lock_atom(atomf);
- spin_lock_atom(atomh);
+ spin_lock_atom_nested(atomh);
}
if (atomh == atomf || !atom_isopen(atomh) ||
!atom_isopen(atomf)) {
release_two_atoms(atomf, atomh);
@@ -2794,10 +2796,10 @@ static void lock_two_atoms(txn_atom * on
/* lock the atom with lesser address first */
if (one < two) {
spin_lock_atom(one);
- spin_lock_atom(two);
+ spin_lock_atom_nested(two);
} else {
spin_lock_atom(two);
- spin_lock_atom(one);
+ spin_lock_atom_nested(one);
}
}
--- linux-2.6-git.orig/fs/reiser4/txnmgr.h
+++ linux-2.6-git/fs/reiser4/txnmgr.h
@@ -503,6 +503,7 @@ static inline void spin_lock_atom(txn_at
{
/* check that spinlocks of lower priorities are not held */
assert("", (LOCK_CNT_NIL(spin_locked_txnh) &&
+ LOCK_CNT_NIL(spin_locked_atom) &&
LOCK_CNT_NIL(spin_locked_jnode) &&
LOCK_CNT_NIL(spin_locked_zlock) &&
LOCK_CNT_NIL(rw_locked_dk) &&
@@ -514,6 +515,20 @@ static inline void spin_lock_atom(txn_at
LOCK_CNT_INC(spin_locked);
}
+static inline void spin_lock_atom_nested(txn_atom *atom)
+{
+ assert("", (LOCK_CNT_NIL(spin_locked_txnh) &&
+ LOCK_CNT_NIL(spin_locked_jnode) &&
+ LOCK_CNT_NIL(spin_locked_zlock) &&
+ LOCK_CNT_NIL(rw_locked_dk) &&
+ LOCK_CNT_NIL(rw_locked_tree)));
+
+ spin_lock_nested(&(atom->alock), SINGLE_DEPTH_NESTING);
+
+ LOCK_CNT_INC(spin_locked_atom);
+ LOCK_CNT_INC(spin_locked);
+}
+
static inline int spin_trylock_atom(txn_atom *atom)
{
if (spin_trylock(&(atom->alock))) {
