2022-03-24 17:06:17

by Jakob Koschel

[permalink] [raw]
Subject: [PATCH] ACPI: ipmi: replace usage of found with dedicated list iterator variable

To move the list iterator variable into the list_for_each_entry_*()
macro in the future it should be avoided to use the list iterator
variable after the loop body.

To *never* use the list iterator variable after the loop it was
concluded to use a separate iterator variable instead of a
found boolean [1].

This removes the need to use a found variable and simply checking if
the variable was set, can determine if the break/goto was hit.

Link: https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=EHreAsk5SqXPwr9Y7k9sA6cWXJ6w@mail.gmail.com/
Signed-off-by: Jakob Koschel <[email protected]>
---
drivers/acpi/acpi_ipmi.c | 39 ++++++++++++++++++---------------------
1 file changed, 18 insertions(+), 21 deletions(-)

diff --git a/drivers/acpi/acpi_ipmi.c b/drivers/acpi/acpi_ipmi.c
index a5fe2926bf50..0555f68c2dfd 100644
--- a/drivers/acpi/acpi_ipmi.c
+++ b/drivers/acpi/acpi_ipmi.c
@@ -353,29 +353,27 @@ static void ipmi_flush_tx_msg(struct acpi_ipmi_device *ipmi)
static void ipmi_cancel_tx_msg(struct acpi_ipmi_device *ipmi,
struct acpi_ipmi_msg *msg)
{
- struct acpi_ipmi_msg *tx_msg, *temp;
- bool msg_found = false;
+ struct acpi_ipmi_msg *tx_msg = NULL, *iter, *temp;
unsigned long flags;

spin_lock_irqsave(&ipmi->tx_msg_lock, flags);
- list_for_each_entry_safe(tx_msg, temp, &ipmi->tx_msg_list, head) {
- if (msg == tx_msg) {
- msg_found = true;
- list_del(&tx_msg->head);
+ list_for_each_entry_safe(iter, temp, &ipmi->tx_msg_list, head) {
+ if (msg == iter) {
+ tx_msg = iter;
+ list_del(&iter->head);
break;
}
}
spin_unlock_irqrestore(&ipmi->tx_msg_lock, flags);

- if (msg_found)
+ if (tx_msg)
acpi_ipmi_msg_put(tx_msg);
}

static void ipmi_msg_handler(struct ipmi_recv_msg *msg, void *user_msg_data)
{
struct acpi_ipmi_device *ipmi_device = user_msg_data;
- bool msg_found = false;
- struct acpi_ipmi_msg *tx_msg, *temp;
+ struct acpi_ipmi_msg *tx_msg = NULL, *iter, *temp;
struct device *dev = ipmi_device->dev;
unsigned long flags;

@@ -387,16 +385,16 @@ static void ipmi_msg_handler(struct ipmi_recv_msg *msg, void *user_msg_data)
}

spin_lock_irqsave(&ipmi_device->tx_msg_lock, flags);
- list_for_each_entry_safe(tx_msg, temp, &ipmi_device->tx_msg_list, head) {
- if (msg->msgid == tx_msg->tx_msgid) {
- msg_found = true;
- list_del(&tx_msg->head);
+ list_for_each_entry_safe(iter, temp, &ipmi_device->tx_msg_list, head) {
+ if (msg->msgid == iter->tx_msgid) {
+ tx_msg = iter;
+ list_del(&iter->head);
break;
}
}
spin_unlock_irqrestore(&ipmi_device->tx_msg_lock, flags);

- if (!msg_found) {
+ if (!tx_msg) {
dev_warn(dev,
"Unexpected response (msg id %ld) is returned.\n",
msg->msgid);
@@ -482,15 +480,14 @@ static void ipmi_register_bmc(int iface, struct device *dev)

static void ipmi_bmc_gone(int iface)
{
- struct acpi_ipmi_device *ipmi_device, *temp;
- bool dev_found = false;
+ struct acpi_ipmi_device *ipmi_device = NULL, *iter, *temp;

mutex_lock(&driver_data.ipmi_lock);
- list_for_each_entry_safe(ipmi_device, temp,
+ list_for_each_entry_safe(iter, temp,
&driver_data.ipmi_devices, head) {
- if (ipmi_device->ipmi_ifnum != iface) {
- dev_found = true;
- __ipmi_dev_kill(ipmi_device);
+ if (iter->ipmi_ifnum != iface) {
+ ipmi_device = iter;
+ __ipmi_dev_kill(iter);
break;
}
}
@@ -500,7 +497,7 @@ static void ipmi_bmc_gone(int iface)
struct acpi_ipmi_device, head);
mutex_unlock(&driver_data.ipmi_lock);

- if (dev_found) {
+ if (ipmi_device) {
ipmi_flush_tx_msg(ipmi_device);
acpi_ipmi_dev_put(ipmi_device);
}

base-commit: f443e374ae131c168a065ea1748feac6b2e76613
--
2.25.1


2022-03-25 18:55:04

by Rafael J. Wysocki

[permalink] [raw]
Subject: Re: [PATCH] ACPI: ipmi: replace usage of found with dedicated list iterator variable

On Thu, Mar 24, 2022 at 8:04 AM Jakob Koschel <[email protected]> wrote:
>
> To move the list iterator variable into the list_for_each_entry_*()
> macro in the future it should be avoided to use the list iterator
> variable after the loop body.
>
> To *never* use the list iterator variable after the loop it was
> concluded to use a separate iterator variable instead of a
> found boolean [1].
>
> This removes the need to use a found variable and simply checking if
> the variable was set, can determine if the break/goto was hit.
>
> Link: https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=EHreAsk5SqXPwr9Y7k9sA6cWXJ6w@mail.gmail.com/
> Signed-off-by: Jakob Koschel <[email protected]>
> ---
> drivers/acpi/acpi_ipmi.c | 39 ++++++++++++++++++---------------------
> 1 file changed, 18 insertions(+), 21 deletions(-)
>
> diff --git a/drivers/acpi/acpi_ipmi.c b/drivers/acpi/acpi_ipmi.c
> index a5fe2926bf50..0555f68c2dfd 100644
> --- a/drivers/acpi/acpi_ipmi.c
> +++ b/drivers/acpi/acpi_ipmi.c
> @@ -353,29 +353,27 @@ static void ipmi_flush_tx_msg(struct acpi_ipmi_device *ipmi)
> static void ipmi_cancel_tx_msg(struct acpi_ipmi_device *ipmi,
> struct acpi_ipmi_msg *msg)
> {
> - struct acpi_ipmi_msg *tx_msg, *temp;
> - bool msg_found = false;
> + struct acpi_ipmi_msg *tx_msg = NULL, *iter, *temp;
> unsigned long flags;
>
> spin_lock_irqsave(&ipmi->tx_msg_lock, flags);
> - list_for_each_entry_safe(tx_msg, temp, &ipmi->tx_msg_list, head) {
> - if (msg == tx_msg) {
> - msg_found = true;
> - list_del(&tx_msg->head);
> + list_for_each_entry_safe(iter, temp, &ipmi->tx_msg_list, head) {
> + if (msg == iter) {
> + tx_msg = iter;
> + list_del(&iter->head);
> break;
> }
> }
> spin_unlock_irqrestore(&ipmi->tx_msg_lock, flags);
>
> - if (msg_found)
> + if (tx_msg)
> acpi_ipmi_msg_put(tx_msg);
> }
>
> static void ipmi_msg_handler(struct ipmi_recv_msg *msg, void *user_msg_data)
> {
> struct acpi_ipmi_device *ipmi_device = user_msg_data;
> - bool msg_found = false;
> - struct acpi_ipmi_msg *tx_msg, *temp;
> + struct acpi_ipmi_msg *tx_msg = NULL, *iter, *temp;
> struct device *dev = ipmi_device->dev;
> unsigned long flags;
>
> @@ -387,16 +385,16 @@ static void ipmi_msg_handler(struct ipmi_recv_msg *msg, void *user_msg_data)
> }
>
> spin_lock_irqsave(&ipmi_device->tx_msg_lock, flags);
> - list_for_each_entry_safe(tx_msg, temp, &ipmi_device->tx_msg_list, head) {
> - if (msg->msgid == tx_msg->tx_msgid) {
> - msg_found = true;
> - list_del(&tx_msg->head);
> + list_for_each_entry_safe(iter, temp, &ipmi_device->tx_msg_list, head) {
> + if (msg->msgid == iter->tx_msgid) {
> + tx_msg = iter;
> + list_del(&iter->head);
> break;
> }
> }
> spin_unlock_irqrestore(&ipmi_device->tx_msg_lock, flags);
>
> - if (!msg_found) {
> + if (!tx_msg) {
> dev_warn(dev,
> "Unexpected response (msg id %ld) is returned.\n",
> msg->msgid);
> @@ -482,15 +480,14 @@ static void ipmi_register_bmc(int iface, struct device *dev)
>
> static void ipmi_bmc_gone(int iface)
> {
> - struct acpi_ipmi_device *ipmi_device, *temp;
> - bool dev_found = false;
> + struct acpi_ipmi_device *ipmi_device = NULL, *iter, *temp;
>
> mutex_lock(&driver_data.ipmi_lock);
> - list_for_each_entry_safe(ipmi_device, temp,
> + list_for_each_entry_safe(iter, temp,
> &driver_data.ipmi_devices, head) {
> - if (ipmi_device->ipmi_ifnum != iface) {
> - dev_found = true;
> - __ipmi_dev_kill(ipmi_device);
> + if (iter->ipmi_ifnum != iface) {
> + ipmi_device = iter;
> + __ipmi_dev_kill(iter);
> break;
> }
> }
> @@ -500,7 +497,7 @@ static void ipmi_bmc_gone(int iface)
> struct acpi_ipmi_device, head);
> mutex_unlock(&driver_data.ipmi_lock);
>
> - if (dev_found) {
> + if (ipmi_device) {
> ipmi_flush_tx_msg(ipmi_device);
> acpi_ipmi_dev_put(ipmi_device);
> }
>
> base-commit: f443e374ae131c168a065ea1748feac6b2e76613
> --

Applied as 5.18-rc material, thanks!