lkml.org 
[lkml]   [2018]   [Jul]   [17]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v2] net/9p/client.c: fix misuse of spin_lock_irqsave for p9_client lock
Date
In p9_read_work(), we use spin_lock for client->lock, but misuse
spin_lock_irqsave for it in p9_fid_create(). As p9_client lock won't be
locked in irq context, so spin_lock is enough. And that will improve the
performance.

Rebased on 9p-next.

Signed-off-by: Jun Piao <piaojun@huawei.com>
---
net/9p/client.c | 18 ++++++++----------
net/9p/trans_fd.c | 7 +++----
2 files changed, 11 insertions(+), 14 deletions(-)

diff --git a/net/9p/client.c b/net/9p/client.c
index 30f9aee..f6897ee 100644
--- a/net/9p/client.c
+++ b/net/9p/client.c
@@ -275,14 +275,14 @@ static struct p9_fcall *p9_fcall_alloc(int alloc_msize)
INIT_LIST_HEAD(&req->req_list);

idr_preload(GFP_NOFS);
- spin_lock_irq(&c->lock);
+ spin_lock(&c->lock);
if (type == P9_TVERSION)
tag = idr_alloc(&c->reqs, req, P9_NOTAG, P9_NOTAG + 1,
GFP_NOWAIT);
else
tag = idr_alloc(&c->reqs, req, 0, P9_NOTAG, GFP_NOWAIT);
req->tc->tag = tag;
- spin_unlock_irq(&c->lock);
+ spin_unlock(&c->lock);
idr_preload_end();
if (tag < 0)
goto free;
@@ -328,13 +328,12 @@ struct p9_req_t *p9_tag_lookup(struct p9_client *c, u16 tag)
*/
static void p9_free_req(struct p9_client *c, struct p9_req_t *r)
{
- unsigned long flags;
u16 tag = r->tc->tag;

p9_debug(P9_DEBUG_MUX, "clnt %p req %p tag: %d\n", c, r, tag);
- spin_lock_irqsave(&c->lock, flags);
+ spin_lock(&c->lock);
idr_remove(&c->reqs, tag);
- spin_unlock_irqrestore(&c->lock, flags);
+ spin_unlock(&c->lock);
kfree(r->tc);
kfree(r->rc);
kmem_cache_free(p9_req_cache, r);
@@ -846,10 +845,10 @@ static struct p9_fid *p9_fid_create(struct p9_client *clnt)
fid->fid = 0;

idr_preload(GFP_KERNEL);
- spin_lock_irq(&clnt->lock);
+ spin_lock(&clnt->lock);
ret = idr_alloc_u32(&clnt->fids, fid, &fid->fid, P9_NOFID - 1,
GFP_NOWAIT);
- spin_unlock_irq(&clnt->lock);
+ spin_unlock(&clnt->lock);
idr_preload_end();

if (!ret)
@@ -862,13 +861,12 @@ static struct p9_fid *p9_fid_create(struct p9_client *clnt)
static void p9_fid_destroy(struct p9_fid *fid)
{
struct p9_client *clnt;
- unsigned long flags;

p9_debug(P9_DEBUG_FID, "fid %d\n", fid->fid);
clnt = fid->clnt;
- spin_lock_irqsave(&clnt->lock, flags);
+ spin_lock(&clnt->lock);
idr_remove(&clnt->fids, fid->fid);
- spin_unlock_irqrestore(&clnt->lock, flags);
+ spin_unlock(&clnt->lock);
kfree(fid->rdir);
kfree(fid);
}
diff --git a/net/9p/trans_fd.c b/net/9p/trans_fd.c
index bf459ee..94ef685 100644
--- a/net/9p/trans_fd.c
+++ b/net/9p/trans_fd.c
@@ -197,15 +197,14 @@ static void p9_mux_poll_stop(struct p9_conn *m)
static void p9_conn_cancel(struct p9_conn *m, int err)
{
struct p9_req_t *req, *rtmp;
- unsigned long flags;
LIST_HEAD(cancel_list);

p9_debug(P9_DEBUG_ERROR, "mux %p err %d\n", m, err);

- spin_lock_irqsave(&m->client->lock, flags);
+ spin_lock(&m->client->lock);

if (m->err) {
- spin_unlock_irqrestore(&m->client->lock, flags);
+ spin_unlock(&m->client->lock);
return;
}

@@ -217,7 +216,7 @@ static void p9_conn_cancel(struct p9_conn *m, int err)
list_for_each_entry_safe(req, rtmp, &m->unsent_req_list, req_list) {
list_move(&req->req_list, &cancel_list);
}
- spin_unlock_irqrestore(&m->client->lock, flags);
+ spin_unlock(&m->client->lock);

list_for_each_entry_safe(req, rtmp, &cancel_list, req_list) {
p9_debug(P9_DEBUG_ERROR, "call back req %p\n", req);
--
\
 
 \ /
  Last update: 2018-07-17 08:26    [W:0.079 / U:0.476 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site