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-rw-r--r--fs/dlm/ast.c74
1 files changed, 58 insertions, 16 deletions
diff --git a/fs/dlm/ast.c b/fs/dlm/ast.c
index dc2ad60..4314f0d 100644
--- a/fs/dlm/ast.c
+++ b/fs/dlm/ast.c
@@ -2,7 +2,7 @@
*******************************************************************************
**
** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
-** Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved.
+** Copyright (C) 2004-2010 Red Hat, Inc. All rights reserved.
**
** This copyrighted material is made available to anyone wishing to use,
** modify, copy, or redistribute it subject to the terms and conditions
@@ -33,10 +33,10 @@ void dlm_del_ast(struct dlm_lkb *lkb)
spin_unlock(&ast_queue_lock);
}
-void dlm_add_ast(struct dlm_lkb *lkb, int type, int bastmode)
+void dlm_add_ast(struct dlm_lkb *lkb, int type, int mode)
{
if (lkb->lkb_flags & DLM_IFL_USER) {
- dlm_user_add_ast(lkb, type, bastmode);
+ dlm_user_add_ast(lkb, type, mode);
return;
}
@@ -44,10 +44,21 @@ void dlm_add_ast(struct dlm_lkb *lkb, int type, int bastmode)
if (!(lkb->lkb_ast_type & (AST_COMP | AST_BAST))) {
kref_get(&lkb->lkb_ref);
list_add_tail(&lkb->lkb_astqueue, &ast_queue);
+ lkb->lkb_ast_first = type;
}
+
+ /* sanity check, this should not happen */
+
+ if ((type == AST_COMP) && (lkb->lkb_ast_type & AST_COMP))
+ log_print("repeat cast %d castmode %d lock %x %s",
+ mode, lkb->lkb_castmode,
+ lkb->lkb_id, lkb->lkb_resource->res_name);
+
lkb->lkb_ast_type |= type;
- if (bastmode)
- lkb->lkb_bastmode = bastmode;
+ if (type == AST_BAST)
+ lkb->lkb_bastmode = mode;
+ else
+ lkb->lkb_castmode = mode;
spin_unlock(&ast_queue_lock);
set_bit(WAKE_ASTS, &astd_wakeflags);
@@ -59,9 +70,9 @@ static void process_asts(void)
struct dlm_ls *ls = NULL;
struct dlm_rsb *r = NULL;
struct dlm_lkb *lkb;
- void (*cast) (void *astparam);
- void (*bast) (void *astparam, int mode);
- int type = 0, bastmode;
+ void (*castfn) (void *astparam);
+ void (*bastfn) (void *astparam, int mode);
+ int type, first, bastmode, castmode, do_bast, do_cast, last_castmode;
repeat:
spin_lock(&ast_queue_lock);
@@ -75,17 +86,48 @@ repeat:
list_del(&lkb->lkb_astqueue);
type = lkb->lkb_ast_type;
lkb->lkb_ast_type = 0;
+ first = lkb->lkb_ast_first;
+ lkb->lkb_ast_first = 0;
bastmode = lkb->lkb_bastmode;
-
+ castmode = lkb->lkb_castmode;
+ castfn = lkb->lkb_astfn;
+ bastfn = lkb->lkb_bastfn;
spin_unlock(&ast_queue_lock);
- cast = lkb->lkb_astfn;
- bast = lkb->lkb_bastfn;
-
- if ((type & AST_COMP) && cast)
- cast(lkb->lkb_astparam);
- if ((type & AST_BAST) && bast)
- bast(lkb->lkb_astparam, bastmode);
+ do_cast = (type & AST_COMP) && castfn;
+ do_bast = (type & AST_BAST) && bastfn;
+
+ /* Skip a bast if its blocking mode is compatible with the
+ granted mode of the preceding cast. */
+
+ if (do_bast) {
+ if (first == AST_COMP)
+ last_castmode = castmode;
+ else
+ last_castmode = lkb->lkb_castmode_done;
+ if (dlm_modes_compat(bastmode, last_castmode))
+ do_bast = 0;
+ }
+
+ if (first == AST_COMP) {
+ if (do_cast)
+ castfn(lkb->lkb_astparam);
+ if (do_bast)
+ bastfn(lkb->lkb_astparam, bastmode);
+ } else if (first == AST_BAST) {
+ if (do_bast)
+ bastfn(lkb->lkb_astparam, bastmode);
+ if (do_cast)
+ castfn(lkb->lkb_astparam);
+ } else {
+ log_error(ls, "bad ast_first %d ast_type %d",
+ first, type);
+ }
+
+ if (do_cast)
+ lkb->lkb_castmode_done = castmode;
+ if (do_bast)
+ lkb->lkb_bastmode_done = bastmode;
/* this removes the reference added by dlm_add_ast
and may result in the lkb being freed */