[Re-send][PATCH] gpu/ipu-v3:reduce protected code area in ipu idmac get/put

From: Bernard
Date: Mon Sep 21 2020 - 07:19:28 EST


This change will speed-up a bit these ipu_idmac_get &
ipu_idmac_put processing and there is no need to protect
kzalloc & kfree.

Signed-off-by: Bernard Zhao <bernard@xxxxxxxx>
---
drivers/gpu/ipu-v3/ipu-common.c | 24 +++++++++++++-----------
1 file changed, 13 insertions(+), 11 deletions(-)

diff --git a/drivers/gpu/ipu-v3/ipu-common.c b/drivers/gpu/ipu-v3/ipu-common.c
index b3dae9ec1a38..8b3a57864c2e 100644
--- a/drivers/gpu/ipu-v3/ipu-common.c
+++ b/drivers/gpu/ipu-v3/ipu-common.c
@@ -267,29 +267,30 @@ EXPORT_SYMBOL_GPL(ipu_rot_mode_to_degrees);
struct ipuv3_channel *ipu_idmac_get(struct ipu_soc *ipu, unsigned num)
{
struct ipuv3_channel *channel;
+ struct ipuv3_channel *entry;

dev_dbg(ipu->dev, "%s %d\n", __func__, num);

if (num > 63)
return ERR_PTR(-ENODEV);

+ channel = kzalloc(sizeof(*channel), GFP_KERNEL);
+ if (!channel)
+ return ERR_PTR(-ENOMEM);
+
+ channel->num = num;
+ channel->ipu = ipu;
+
mutex_lock(&ipu->channel_lock);

- list_for_each_entry(channel, &ipu->channels, list) {
- if (channel->num == num) {
+ list_for_each_entry(entry, &ipu->channels, list) {
+ if (entry->num == num) {
+ kfree(channel);
channel = ERR_PTR(-EBUSY);
goto out;
}
}

- channel = kzalloc(sizeof(*channel), GFP_KERNEL);
- if (!channel) {
- channel = ERR_PTR(-ENOMEM);
- goto out;
- }
-
- channel->num = num;
- channel->ipu = ipu;
list_add(&channel->list, &ipu->channels);

out:
@@ -308,9 +309,10 @@ void ipu_idmac_put(struct ipuv3_channel *channel)
mutex_lock(&ipu->channel_lock);

list_del(&channel->list);
- kfree(channel);

mutex_unlock(&ipu->channel_lock);
+
+ kfree(channel);
}
EXPORT_SYMBOL_GPL(ipu_idmac_put);

--
2.28.0