Re: [PATCH v2 11/20] rpmsg: glink: Fix idr_lock from mutex to spinlock

From: Chris Lew
Date: Mon Aug 28 2017 - 17:51:58 EST


Hi Sricharan,

Minor bug in this patch.

On 8/24/2017 12:21 AM, Sricharan R wrote:
[..]
@@ -829,11 +839,14 @@ static int qcom_glink_rx_open(struct qcom_glink *glink, unsigned int rcid,
struct device_node *node;
int lcid;
int ret;
+ unsigned long flags;
+ spin_lock_irqsave(&glink->idr_lock, flags);
idr_for_each_entry(&glink->lcids, channel, lcid) {
if (!strcmp(channel->name, name))
break;
}
+ spin_unlock_irqrestore(&glink->idr_lock, flags);
if (!channel) {
channel = qcom_glink_alloc_channel(glink, name);
@@ -844,15 +857,15 @@ static int qcom_glink_rx_open(struct qcom_glink *glink, unsigned int rcid,
create_device = true;
}
- mutex_lock(&glink->idr_lock);
+ spin_lock_irqsave(&glink->idr_lock, flags);
ret = idr_alloc(&glink->rcids, channel, rcid, rcid + 1, GFP_KERNEL);

I think GFP_KERNEL should be changed to GFP_ATOMIC if the mutex is changed to spinlock.

Thanks,
Chris
--
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