svcrdma: Use standard Linux lists for context cache

Replace the one-off linked list implementation used to implement the
context cache with the standard Linux list_head lists. Add a context
counter to catch resource leaks. A WARN_ON will be added later to
ensure that we've freed all contexts.

Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
This commit is contained in:
Tom Tucker 2008-04-30 20:44:39 -05:00
parent 02e7452de7
commit 8740767376
2 changed files with 29 additions and 23 deletions

View file

@ -72,7 +72,7 @@ extern atomic_t rdma_stat_sq_prod;
*/
struct svc_rdma_op_ctxt {
struct svc_rdma_op_ctxt *read_hdr;
struct svc_rdma_op_ctxt *next;
struct list_head free_list;
struct xdr_buf arg;
struct list_head dto_q;
enum ib_wr_opcode wr_op;
@ -104,7 +104,8 @@ struct svcxprt_rdma {
struct ib_pd *sc_pd;
struct svc_rdma_op_ctxt *sc_ctxt_head;
atomic_t sc_ctxt_used;
struct list_head sc_ctxt_free;
int sc_ctxt_cnt;
int sc_ctxt_bump;
int sc_ctxt_max;

View file

@ -103,8 +103,8 @@ static int rdma_bump_context_cache(struct svcxprt_rdma *xprt)
spin_lock_bh(&xprt->sc_ctxt_lock);
if (ctxt) {
at_least_one = 1;
ctxt->next = xprt->sc_ctxt_head;
xprt->sc_ctxt_head = ctxt;
INIT_LIST_HEAD(&ctxt->free_list);
list_add(&ctxt->free_list, &xprt->sc_ctxt_free);
} else {
/* kmalloc failed...give up for now */
xprt->sc_ctxt_cnt--;
@ -123,7 +123,7 @@ struct svc_rdma_op_ctxt *svc_rdma_get_context(struct svcxprt_rdma *xprt)
while (1) {
spin_lock_bh(&xprt->sc_ctxt_lock);
if (unlikely(xprt->sc_ctxt_head == NULL)) {
if (unlikely(list_empty(&xprt->sc_ctxt_free))) {
/* Try to bump my cache. */
spin_unlock_bh(&xprt->sc_ctxt_lock);
@ -136,12 +136,15 @@ struct svc_rdma_op_ctxt *svc_rdma_get_context(struct svcxprt_rdma *xprt)
schedule_timeout_uninterruptible(msecs_to_jiffies(500));
continue;
}
ctxt = xprt->sc_ctxt_head;
xprt->sc_ctxt_head = ctxt->next;
ctxt = list_entry(xprt->sc_ctxt_free.next,
struct svc_rdma_op_ctxt,
free_list);
list_del_init(&ctxt->free_list);
spin_unlock_bh(&xprt->sc_ctxt_lock);
ctxt->xprt = xprt;
INIT_LIST_HEAD(&ctxt->dto_q);
ctxt->count = 0;
atomic_inc(&xprt->sc_ctxt_used);
break;
}
return ctxt;
@ -163,10 +166,11 @@ void svc_rdma_put_context(struct svc_rdma_op_ctxt *ctxt, int free_pages)
ctxt->sge[i].addr,
ctxt->sge[i].length,
ctxt->direction);
spin_lock_bh(&xprt->sc_ctxt_lock);
ctxt->next = xprt->sc_ctxt_head;
xprt->sc_ctxt_head = ctxt;
list_add(&ctxt->free_list, &xprt->sc_ctxt_free);
spin_unlock_bh(&xprt->sc_ctxt_lock);
atomic_dec(&xprt->sc_ctxt_used);
}
/* ib_cq event handler */
@ -412,28 +416,29 @@ static void create_context_cache(struct svcxprt_rdma *xprt,
xprt->sc_ctxt_max = ctxt_max;
xprt->sc_ctxt_bump = ctxt_bump;
xprt->sc_ctxt_cnt = 0;
xprt->sc_ctxt_head = NULL;
atomic_set(&xprt->sc_ctxt_used, 0);
INIT_LIST_HEAD(&xprt->sc_ctxt_free);
for (i = 0; i < ctxt_count; i++) {
ctxt = kmalloc(sizeof(*ctxt), GFP_KERNEL);
if (ctxt) {
ctxt->next = xprt->sc_ctxt_head;
xprt->sc_ctxt_head = ctxt;
INIT_LIST_HEAD(&ctxt->free_list);
list_add(&ctxt->free_list, &xprt->sc_ctxt_free);
xprt->sc_ctxt_cnt++;
}
}
}
static void destroy_context_cache(struct svc_rdma_op_ctxt *ctxt)
static void destroy_context_cache(struct svcxprt_rdma *xprt)
{
struct svc_rdma_op_ctxt *next;
if (!ctxt)
return;
do {
next = ctxt->next;
while (!list_empty(&xprt->sc_ctxt_free)) {
struct svc_rdma_op_ctxt *ctxt;
ctxt = list_entry(xprt->sc_ctxt_free.next,
struct svc_rdma_op_ctxt,
free_list);
list_del_init(&ctxt->free_list);
kfree(ctxt);
ctxt = next;
} while (next);
}
}
static struct svcxprt_rdma *rdma_create_xprt(struct svc_serv *serv,
@ -470,7 +475,7 @@ static struct svcxprt_rdma *rdma_create_xprt(struct svc_serv *serv,
reqs +
cma_xprt->sc_sq_depth +
RPCRDMA_MAX_THREADS + 1); /* max */
if (!cma_xprt->sc_ctxt_head) {
if (list_empty(&cma_xprt->sc_ctxt_free)) {
kfree(cma_xprt);
return NULL;
}
@ -976,7 +981,7 @@ static void svc_rdma_free(struct svc_xprt *xprt)
if (rdma->sc_pd && !IS_ERR(rdma->sc_pd))
ib_dealloc_pd(rdma->sc_pd);
destroy_context_cache(rdma->sc_ctxt_head);
destroy_context_cache(rdma);
kfree(rdma);
}