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[PATCH] knfsd: Create cache_lookup function instead of using a macro to declare one

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The C++-like 'template' approach proves to be too ugly and hard to work with.

The old 'template' won't go away until all users are updated.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
NeilBrown
2006-03-27 01:15:02 -08:00
committed by Linus Torvalds
parent 7d317f2c9f
commit 15a5f6bd23
2 changed files with 110 additions and 0 deletions
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12
include/linux/sunrpc/cache.h
View File

@@ -81,6 +81,11 @@ struct cache_detail {
struct cache_detail *cd, struct cache_detail *cd,
struct cache_head *h); struct cache_head *h);
struct cache_head * (*alloc)(void);
int (*match)(struct cache_head *orig, struct cache_head *new);
void (*init)(struct cache_head *orig, struct cache_head *new);
void (*update)(struct cache_head *orig, struct cache_head *new);
/* fields below this comment are for internal use /* fields below this comment are for internal use
* and should not be touched by cache owners * and should not be touched by cache owners
*/ */
@@ -237,6 +242,13 @@ RTN *FNAME ARGS \
& FUNC##_cache, FUNC##_hash(item), FUNC##_match(item, tmp), \ & FUNC##_cache, FUNC##_hash(item), FUNC##_match(item, tmp), \
STRUCT##_init(new, item), STRUCT##_update(tmp, item)) STRUCT##_init(new, item), STRUCT##_update(tmp, item))
extern struct cache_head *
sunrpc_cache_lookup(struct cache_detail *detail,
struct cache_head *key, int hash);
extern struct cache_head *
sunrpc_cache_update(struct cache_detail *detail,
struct cache_head *new, struct cache_head *old, int hash);
#define cache_for_each(pos, detail, index, member) \ #define cache_for_each(pos, detail, index, member) \
for (({read_lock(&(detail)->hash_lock); index = (detail)->hash_size;}) ; \ for (({read_lock(&(detail)->hash_lock); index = (detail)->hash_size;}) ; \

98
net/sunrpc/cache.c
View File

@@ -47,6 +47,104 @@ void cache_init(struct cache_head *h)
h->last_refresh = now; h->last_refresh = now;
} }
struct cache_head *sunrpc_cache_lookup(struct cache_detail *detail,
struct cache_head *key, int hash)
{
struct cache_head **head, **hp;
struct cache_head *new = NULL;
head = &detail->hash_table[hash];
read_lock(&detail->hash_lock);
for (hp=head; *hp != NULL ; hp = &(*hp)->next) {
struct cache_head *tmp = *hp;
if (detail->match(tmp, key)) {
cache_get(tmp);
read_unlock(&detail->hash_lock);
return tmp;
}
}
read_unlock(&detail->hash_lock);
/* Didn't find anything, insert an empty entry */
new = detail->alloc();
if (!new)
return NULL;
cache_init(new);
write_lock(&detail->hash_lock);
/* check if entry appeared while we slept */
for (hp=head; *hp != NULL ; hp = &(*hp)->next) {
struct cache_head *tmp = *hp;
if (detail->match(tmp, key)) {
cache_get(tmp);
write_unlock(&detail->hash_lock);
detail->cache_put(new, detail);
return tmp;
}
}
detail->init(new, key);
new->next = *head;
*head = new;
detail->entries++;
cache_get(new);
write_unlock(&detail->hash_lock);
return new;
}
EXPORT_SYMBOL(sunrpc_cache_lookup);
struct cache_head *sunrpc_cache_update(struct cache_detail *detail,
struct cache_head *new, struct cache_head *old, int hash)
{
/* The 'old' entry is to be replaced by 'new'.
* If 'old' is not VALID, we update it directly,
* otherwise we need to replace it
*/
struct cache_head **head;
struct cache_head *tmp;
if (!test_bit(CACHE_VALID, &old->flags)) {
write_lock(&detail->hash_lock);
if (!test_bit(CACHE_VALID, &old->flags)) {
if (test_bit(CACHE_NEGATIVE, &new->flags))
set_bit(CACHE_NEGATIVE, &old->flags);
else
detail->update(old, new);
/* FIXME cache_fresh should come first */
write_unlock(&detail->hash_lock);
cache_fresh(detail, old, new->expiry_time);
return old;
}
write_unlock(&detail->hash_lock);
}
/* We need to insert a new entry */
tmp = detail->alloc();
if (!tmp) {
detail->cache_put(old, detail);
return NULL;
}
cache_init(tmp);
detail->init(tmp, old);
head = &detail->hash_table[hash];
write_lock(&detail->hash_lock);
if (test_bit(CACHE_NEGATIVE, &new->flags))
set_bit(CACHE_NEGATIVE, &tmp->flags);
else
detail->update(tmp, new);
tmp->next = *head;
*head = tmp;
cache_get(tmp);
write_unlock(&detail->hash_lock);
cache_fresh(detail, tmp, new->expiry_time);
cache_fresh(detail, old, 0);
detail->cache_put(old, detail);
return tmp;
}
EXPORT_SYMBOL(sunrpc_cache_update);
static int cache_make_upcall(struct cache_detail *detail, struct cache_head *h); static int cache_make_upcall(struct cache_detail *detail, struct cache_head *h);
/* /*