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Diffstat (limited to 'net/sunrpc/cache.c')
-rw-r--r--net/sunrpc/cache.c128
1 files changed, 74 insertions, 54 deletions
diff --git a/net/sunrpc/cache.c b/net/sunrpc/cache.c
index bd843a81afa0..af0ddd28b081 100644
--- a/net/sunrpc/cache.c
+++ b/net/sunrpc/cache.c
@@ -32,13 +32,13 @@
#include <linux/sunrpc/cache.h>
#include <linux/sunrpc/stats.h>
#include <linux/sunrpc/rpc_pipe_fs.h>
+#include <trace/events/sunrpc.h>
#include "netns.h"
#define RPCDBG_FACILITY RPCDBG_CACHE
static bool cache_defer_req(struct cache_req *req, struct cache_head *item);
static void cache_revisit_request(struct cache_head *item);
-static bool cache_listeners_exist(struct cache_detail *detail);
static void cache_init(struct cache_head *h, struct cache_detail *detail)
{
@@ -65,13 +65,14 @@ static struct cache_head *sunrpc_cache_find_rcu(struct cache_detail *detail,
rcu_read_lock();
hlist_for_each_entry_rcu(tmp, head, cache_list) {
- if (detail->match(tmp, key)) {
- if (cache_is_expired(detail, tmp))
- continue;
- tmp = cache_get_rcu(tmp);
- rcu_read_unlock();
- return tmp;
- }
+ if (!detail->match(tmp, key))
+ continue;
+ if (test_bit(CACHE_VALID, &tmp->flags) &&
+ cache_is_expired(detail, tmp))
+ continue;
+ tmp = cache_get_rcu(tmp);
+ rcu_read_unlock();
+ return tmp;
}
rcu_read_unlock();
return NULL;
@@ -113,18 +114,21 @@ static struct cache_head *sunrpc_cache_add_entry(struct cache_detail *detail,
spin_lock(&detail->hash_lock);
/* check if entry appeared while we slept */
- hlist_for_each_entry_rcu(tmp, head, cache_list) {
- if (detail->match(tmp, key)) {
- if (cache_is_expired(detail, tmp)) {
- sunrpc_begin_cache_remove_entry(tmp, detail);
- freeme = tmp;
- break;
- }
- cache_get(tmp);
- spin_unlock(&detail->hash_lock);
- cache_put(new, detail);
- return tmp;
+ hlist_for_each_entry_rcu(tmp, head, cache_list,
+ lockdep_is_held(&detail->hash_lock)) {
+ if (!detail->match(tmp, key))
+ continue;
+ if (test_bit(CACHE_VALID, &tmp->flags) &&
+ cache_is_expired(detail, tmp)) {
+ sunrpc_begin_cache_remove_entry(tmp, detail);
+ trace_cache_entry_expired(detail, tmp);
+ freeme = tmp;
+ break;
}
+ cache_get(tmp);
+ spin_unlock(&detail->hash_lock);
+ cache_put(new, detail);
+ return tmp;
}
hlist_add_head_rcu(&new->cache_list, head);
@@ -174,6 +178,25 @@ static void cache_fresh_unlocked(struct cache_head *head,
}
}
+static void cache_make_negative(struct cache_detail *detail,
+ struct cache_head *h)
+{
+ set_bit(CACHE_NEGATIVE, &h->flags);
+ trace_cache_entry_make_negative(detail, h);
+}
+
+static void cache_entry_update(struct cache_detail *detail,
+ struct cache_head *h,
+ struct cache_head *new)
+{
+ if (!test_bit(CACHE_NEGATIVE, &new->flags)) {
+ detail->update(h, new);
+ trace_cache_entry_update(detail, h);
+ } else {
+ cache_make_negative(detail, h);
+ }
+}
+
struct cache_head *sunrpc_cache_update(struct cache_detail *detail,
struct cache_head *new, struct cache_head *old, int hash)
{
@@ -186,10 +209,7 @@ struct cache_head *sunrpc_cache_update(struct cache_detail *detail,
if (!test_bit(CACHE_VALID, &old->flags)) {
spin_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);
+ cache_entry_update(detail, old, new);
cache_fresh_locked(old, new->expiry_time, detail);
spin_unlock(&detail->hash_lock);
cache_fresh_unlocked(old, detail);
@@ -207,10 +227,7 @@ struct cache_head *sunrpc_cache_update(struct cache_detail *detail,
detail->init(tmp, old);
spin_lock(&detail->hash_lock);
- if (test_bit(CACHE_NEGATIVE, &new->flags))
- set_bit(CACHE_NEGATIVE, &tmp->flags);
- else
- detail->update(tmp, new);
+ cache_entry_update(detail, tmp, new);
hlist_add_head(&tmp->cache_list, &detail->hash_table[hash]);
detail->entries++;
cache_get(tmp);
@@ -224,13 +241,6 @@ struct cache_head *sunrpc_cache_update(struct cache_detail *detail,
}
EXPORT_SYMBOL_GPL(sunrpc_cache_update);
-static int cache_make_upcall(struct cache_detail *cd, struct cache_head *h)
-{
- if (cd->cache_upcall)
- return cd->cache_upcall(cd, h);
- return sunrpc_cache_pipe_upcall(cd, h);
-}
-
static inline int cache_is_valid(struct cache_head *h)
{
if (!test_bit(CACHE_VALID, &h->flags))
@@ -259,7 +269,7 @@ static int try_to_negate_entry(struct cache_detail *detail, struct cache_head *h
spin_lock(&detail->hash_lock);
rv = cache_is_valid(h);
if (rv == -EAGAIN) {
- set_bit(CACHE_NEGATIVE, &h->flags);
+ cache_make_negative(detail, h);
cache_fresh_locked(h, seconds_since_boot()+CACHE_NEW_EXPIRY,
detail);
rv = -ENOENT;
@@ -303,17 +313,14 @@ int cache_check(struct cache_detail *detail,
(h->expiry_time != 0 && age > refresh_age/2)) {
dprintk("RPC: Want update, refage=%lld, age=%lld\n",
refresh_age, age);
- if (!test_and_set_bit(CACHE_PENDING, &h->flags)) {
- switch (cache_make_upcall(detail, h)) {
- case -EINVAL:
- rv = try_to_negate_entry(detail, h);
- break;
- case -EAGAIN:
- cache_fresh_unlocked(h, detail);
- break;
- }
- } else if (!cache_listeners_exist(detail))
+ switch (detail->cache_upcall(detail, h)) {
+ case -EINVAL:
rv = try_to_negate_entry(detail, h);
+ break;
+ case -EAGAIN:
+ cache_fresh_unlocked(h, detail);
+ break;
+ }
}
if (rv == -EAGAIN) {
@@ -468,6 +475,7 @@ static int cache_clean(void)
continue;
sunrpc_begin_cache_remove_entry(ch, current_detail);
+ trace_cache_entry_expired(current_detail, ch);
rv = 1;
break;
}
@@ -1195,20 +1203,12 @@ static bool cache_listeners_exist(struct cache_detail *detail)
*
* Each request is at most one page long.
*/
-int sunrpc_cache_pipe_upcall(struct cache_detail *detail, struct cache_head *h)
+static int cache_pipe_upcall(struct cache_detail *detail, struct cache_head *h)
{
-
char *buf;
struct cache_request *crq;
int ret = 0;
- if (!detail->cache_request)
- return -EINVAL;
-
- if (!cache_listeners_exist(detail)) {
- warn_no_listener(detail);
- return -EINVAL;
- }
if (test_bit(CACHE_CLEANED, &h->flags))
/* Too late to make an upcall */
return -EAGAIN;
@@ -1231,6 +1231,7 @@ int sunrpc_cache_pipe_upcall(struct cache_detail *detail, struct cache_head *h)
if (test_bit(CACHE_PENDING, &h->flags)) {
crq->item = cache_get(h);
list_add_tail(&crq->q.list, &detail->queue);
+ trace_cache_entry_upcall(detail, h);
} else
/* Lost a race, no longer PENDING, so don't enqueue */
ret = -EAGAIN;
@@ -1242,8 +1243,27 @@ int sunrpc_cache_pipe_upcall(struct cache_detail *detail, struct cache_head *h)
}
return ret;
}
+
+int sunrpc_cache_pipe_upcall(struct cache_detail *detail, struct cache_head *h)
+{
+ if (test_and_set_bit(CACHE_PENDING, &h->flags))
+ return 0;
+ return cache_pipe_upcall(detail, h);
+}
EXPORT_SYMBOL_GPL(sunrpc_cache_pipe_upcall);
+int sunrpc_cache_pipe_upcall_timeout(struct cache_detail *detail,
+ struct cache_head *h)
+{
+ if (!cache_listeners_exist(detail)) {
+ warn_no_listener(detail);
+ trace_cache_entry_no_listener(detail, h);
+ return -EINVAL;
+ }
+ return sunrpc_cache_pipe_upcall(detail, h);
+}
+EXPORT_SYMBOL_GPL(sunrpc_cache_pipe_upcall_timeout);
+
/*
* parse a message from user-space and pass it
* to an appropriate cache
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.