2018-07-27 19:14:35

by Ivan Khoronzhuk

[permalink] [raw]
Subject: [PATCH net-next] net: ethernet: ti: cpsw: replace unnecessarily macroses on functions

Replace ugly macroses on functions.

Signed-off-by: Ivan Khoronzhuk <[email protected]>
---

Based on net-next/master

drivers/net/ethernet/ti/cpsw.c | 63 +++++++++++++++++-----------------
1 file changed, 32 insertions(+), 31 deletions(-)

diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c
index 1b54c26c2bec..62326a98945b 100644
--- a/drivers/net/ethernet/ti/cpsw.c
+++ b/drivers/net/ethernet/ti/cpsw.c
@@ -565,40 +565,40 @@ static const struct cpsw_stats cpsw_gstrings_ch_stats[] = {
(func)(slave++, ##arg); \
} while (0)

-#define cpsw_dual_emac_src_port_detect(cpsw, status, ndev, skb) \
- do { \
- if (!cpsw->data.dual_emac) \
- break; \
- if (CPDMA_RX_SOURCE_PORT(status) == 1) { \
- ndev = cpsw->slaves[0].ndev; \
- skb->dev = ndev; \
- } else if (CPDMA_RX_SOURCE_PORT(status) == 2) { \
- ndev = cpsw->slaves[1].ndev; \
- skb->dev = ndev; \
- } \
- } while (0)
-#define cpsw_add_mcast(cpsw, priv, addr) \
- do { \
- if (cpsw->data.dual_emac) { \
- struct cpsw_slave *slave = cpsw->slaves + \
- priv->emac_port; \
- int slave_port = cpsw_get_slave_port( \
- slave->slave_num); \
- cpsw_ale_add_mcast(cpsw->ale, addr, \
- 1 << slave_port | ALE_PORT_HOST, \
- ALE_VLAN, slave->port_vlan, 0); \
- } else { \
- cpsw_ale_add_mcast(cpsw->ale, addr, \
- ALE_ALL_PORTS, \
- 0, 0, 0); \
- } \
- } while (0)
-
static inline int cpsw_get_slave_port(u32 slave_num)
{
return slave_num + 1;
}

+static inline void cpsw_src_port_detect(struct cpsw_common *cpsw, int status,
+ struct sk_buff *skb)
+{
+ if (!cpsw->data.dual_emac)
+ return;
+
+ if (CPDMA_RX_SOURCE_PORT(status) == 1)
+ skb->dev = cpsw->slaves[0].ndev;
+ else if (CPDMA_RX_SOURCE_PORT(status) == 2)
+ skb->dev = cpsw->slaves[1].ndev;
+}
+
+static void cpsw_add_mcast(struct cpsw_priv *priv, u8 *addr)
+{
+ struct cpsw_common *cpsw = priv->cpsw;
+
+ if (cpsw->data.dual_emac) {
+ struct cpsw_slave *slave = cpsw->slaves + priv->emac_port;
+ int slave_port = cpsw_get_slave_port(slave->slave_num);
+
+ cpsw_ale_add_mcast(cpsw->ale, addr,
+ 1 << slave_port | ALE_PORT_HOST,
+ ALE_VLAN, slave->port_vlan, 0);
+ return;
+ }
+
+ cpsw_ale_add_mcast(cpsw->ale, addr, ALE_ALL_PORTS, 0, 0, 0);
+}
+
static void cpsw_set_promiscious(struct net_device *ndev, bool enable)
{
struct cpsw_common *cpsw = ndev_to_cpsw(ndev);
@@ -706,7 +706,7 @@ static void cpsw_ndo_set_rx_mode(struct net_device *ndev)

/* program multicast address list into ALE register */
netdev_for_each_mc_addr(ha, ndev) {
- cpsw_add_mcast(cpsw, priv, (u8 *)ha->addr);
+ cpsw_add_mcast(priv, (u8 *)ha->addr);
}
}
}
@@ -801,7 +801,8 @@ static void cpsw_rx_handler(void *token, int len, int status)
int ret = 0;
struct cpsw_common *cpsw = ndev_to_cpsw(ndev);

- cpsw_dual_emac_src_port_detect(cpsw, status, ndev, skb);
+ cpsw_src_port_detect(cpsw, status, skb);
+ ndev = skb->dev;

if (unlikely(status < 0) || unlikely(!netif_running(ndev))) {
/* In dual emac mode check for all interfaces */
--
2.17.1



2018-07-27 19:16:59

by Grygorii Strashko

[permalink] [raw]
Subject: Re: [PATCH net-next] net: ethernet: ti: cpsw: replace unnecessarily macroses on functions



On 07/27/2018 02:13 PM, Ivan Khoronzhuk wrote:
> Replace ugly macroses on functions.
>
> Signed-off-by: Ivan Khoronzhuk <[email protected]>

Reviewed-by: Grygorii Strashko <[email protected]>


--
regards,
-grygorii

2018-07-27 19:22:43

by Joe Perches

[permalink] [raw]
Subject: Re: [PATCH net-next] net: ethernet: ti: cpsw: replace unnecessarily macroses on functions

On Fri, 2018-07-27 at 22:13 +0300, Ivan Khoronzhuk wrote:
> Replace ugly macroses on functions.

Careful, see below.

> diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c
[]
> @@ -565,40 +565,40 @@ static const struct cpsw_stats cpsw_gstrings_ch_stats[] = {
> (func)(slave++, ##arg); \
> } while (0)
>
> -#define cpsw_dual_emac_src_port_detect(cpsw, status, ndev, skb) \
> - do { \
> - if (!cpsw->data.dual_emac) \
> - break; \
> - if (CPDMA_RX_SOURCE_PORT(status) == 1) { \
> - ndev = cpsw->slaves[0].ndev; \
> - skb->dev = ndev; \
> - } else if (CPDMA_RX_SOURCE_PORT(status) == 2) { \
> - ndev = cpsw->slaves[1].ndev; \
> - skb->dev = ndev; \
> - } \
> - } while (0)
> -#define cpsw_add_mcast(cpsw, priv, addr) \
> - do { \
> - if (cpsw->data.dual_emac) { \
> - struct cpsw_slave *slave = cpsw->slaves + \
> - priv->emac_port; \
> - int slave_port = cpsw_get_slave_port( \
> - slave->slave_num); \
> - cpsw_ale_add_mcast(cpsw->ale, addr, \
> - 1 << slave_port | ALE_PORT_HOST, \
> - ALE_VLAN, slave->port_vlan, 0); \
> - } else { \
> - cpsw_ale_add_mcast(cpsw->ale, addr, \
> - ALE_ALL_PORTS, \
> - 0, 0, 0); \
> - } \
> - } while (0)
> -
> static inline int cpsw_get_slave_port(u32 slave_num)
> {
> return slave_num + 1;
> }
>
> +static inline void cpsw_src_port_detect(struct cpsw_common *cpsw, int status,
> + struct sk_buff *skb)
> +{
> + if (!cpsw->data.dual_emac)
> + return;
> +
> + if (CPDMA_RX_SOURCE_PORT(status) == 1)
> + skb->dev = cpsw->slaves[0].ndev;
> + else if (CPDMA_RX_SOURCE_PORT(status) == 2)
> + skb->dev = cpsw->slaves[1].ndev;
> +}

perhaps better as a switch/case

> +
> +static void cpsw_add_mcast(struct cpsw_priv *priv, u8 *addr)
> +{
> + struct cpsw_common *cpsw = priv->cpsw;
> +
> + if (cpsw->data.dual_emac) {
> + struct cpsw_slave *slave = cpsw->slaves + priv->emac_port;
> + int slave_port = cpsw_get_slave_port(slave->slave_num);
> +
> + cpsw_ale_add_mcast(cpsw->ale, addr,
> + 1 << slave_port | ALE_PORT_HOST,
> + ALE_VLAN, slave->port_vlan, 0);
> + return;
> + }
> +
> + cpsw_ale_add_mcast(cpsw->ale, addr, ALE_ALL_PORTS, 0, 0, 0);
> +}
> +
> static void cpsw_set_promiscious(struct net_device *ndev, bool enable)
> {
> struct cpsw_common *cpsw = ndev_to_cpsw(ndev);
> @@ -706,7 +706,7 @@ static void cpsw_ndo_set_rx_mode(struct net_device *ndev)
>
> /* program multicast address list into ALE register */
> netdev_for_each_mc_addr(ha, ndev) {
> - cpsw_add_mcast(cpsw, priv, (u8 *)ha->addr);
> + cpsw_add_mcast(priv, (u8 *)ha->addr);
> }
> }
> }
> @@ -801,7 +801,8 @@ static void cpsw_rx_handler(void *token, int len, int status)
> int ret = 0;
> struct cpsw_common *cpsw = ndev_to_cpsw(ndev);
>
> - cpsw_dual_emac_src_port_detect(cpsw, status, ndev, skb);
> + cpsw_src_port_detect(cpsw, status, skb);
> + ndev = skb->dev;

This is not the same code as the new function
is not guaranteed to succeed or set skb->dev.

> if (unlikely(status < 0) || unlikely(!netif_running(ndev))) {
> /* In dual emac mode check for all interfaces */

2018-07-27 19:37:51

by Ivan Khoronzhuk

[permalink] [raw]
Subject: Re: [PATCH net-next] net: ethernet: ti: cpsw: replace unnecessarily macroses on functions

On Fri, Jul 27, 2018 at 12:21:07PM -0700, Joe Perches wrote:
>On Fri, 2018-07-27 at 22:13 +0300, Ivan Khoronzhuk wrote:
>> Replace ugly macroses on functions.
>
>Careful, see below.
>
>> diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c
>[]
>> @@ -565,40 +565,40 @@ static const struct cpsw_stats cpsw_gstrings_ch_stats[] = {
>> (func)(slave++, ##arg); \
>> } while (0)
>>
>> -#define cpsw_dual_emac_src_port_detect(cpsw, status, ndev, skb) \
>> - do { \
>> - if (!cpsw->data.dual_emac) \
>> - break; \
>> - if (CPDMA_RX_SOURCE_PORT(status) == 1) { \
>> - ndev = cpsw->slaves[0].ndev; \
>> - skb->dev = ndev; \
>> - } else if (CPDMA_RX_SOURCE_PORT(status) == 2) { \
>> - ndev = cpsw->slaves[1].ndev; \
>> - skb->dev = ndev; \
>> - } \
>> - } while (0)
>> -#define cpsw_add_mcast(cpsw, priv, addr) \
>> - do { \
>> - if (cpsw->data.dual_emac) { \
>> - struct cpsw_slave *slave = cpsw->slaves + \
>> - priv->emac_port; \
>> - int slave_port = cpsw_get_slave_port( \
>> - slave->slave_num); \
>> - cpsw_ale_add_mcast(cpsw->ale, addr, \
>> - 1 << slave_port | ALE_PORT_HOST, \
>> - ALE_VLAN, slave->port_vlan, 0); \
>> - } else { \
>> - cpsw_ale_add_mcast(cpsw->ale, addr, \
>> - ALE_ALL_PORTS, \
>> - 0, 0, 0); \
>> - } \
>> - } while (0)
>> -
>> static inline int cpsw_get_slave_port(u32 slave_num)
>> {
>> return slave_num + 1;
>> }
>>
>> +static inline void cpsw_src_port_detect(struct cpsw_common *cpsw, int status,
>> + struct sk_buff *skb)
>> +{
>> + if (!cpsw->data.dual_emac)
>> + return;
>> +
>> + if (CPDMA_RX_SOURCE_PORT(status) == 1)
>> + skb->dev = cpsw->slaves[0].ndev;
>> + else if (CPDMA_RX_SOURCE_PORT(status) == 2)
>> + skb->dev = cpsw->slaves[1].ndev;
>> +}
>
>perhaps better as a switch/case
not better, it's shorter.

>
>> +
>> +static void cpsw_add_mcast(struct cpsw_priv *priv, u8 *addr)
>> +{
>> + struct cpsw_common *cpsw = priv->cpsw;
>> +
>> + if (cpsw->data.dual_emac) {
>> + struct cpsw_slave *slave = cpsw->slaves + priv->emac_port;
>> + int slave_port = cpsw_get_slave_port(slave->slave_num);
>> +
>> + cpsw_ale_add_mcast(cpsw->ale, addr,
>> + 1 << slave_port | ALE_PORT_HOST,
>> + ALE_VLAN, slave->port_vlan, 0);
>> + return;
>> + }
>> +
>> + cpsw_ale_add_mcast(cpsw->ale, addr, ALE_ALL_PORTS, 0, 0, 0);
>> +}
>> +
>> static void cpsw_set_promiscious(struct net_device *ndev, bool enable)
>> {
>> struct cpsw_common *cpsw = ndev_to_cpsw(ndev);
>> @@ -706,7 +706,7 @@ static void cpsw_ndo_set_rx_mode(struct net_device *ndev)
>>
>> /* program multicast address list into ALE register */
>> netdev_for_each_mc_addr(ha, ndev) {
>> - cpsw_add_mcast(cpsw, priv, (u8 *)ha->addr);
>> + cpsw_add_mcast(priv, (u8 *)ha->addr);
>> }
>> }
>> }
>> @@ -801,7 +801,8 @@ static void cpsw_rx_handler(void *token, int len, int status)
>> int ret = 0;
>> struct cpsw_common *cpsw = ndev_to_cpsw(ndev);
>>
>> - cpsw_dual_emac_src_port_detect(cpsw, status, ndev, skb);
>> + cpsw_src_port_detect(cpsw, status, skb);
>> + ndev = skb->dev;
>
>This is not the same code as the new function
>is not guaranteed to succeed or set skb->dev.
Guaranteed by above skb->dev is initialized already.
The function reflects previous macro.

Even more, seems that here is duplication of ndev=skb->dev;
It should be removed at init ), even if it 100% is optimized by complier.
So guaranteed a little more then needed ), will send v2 with removed
ndev = skb->dev at init if no objection.

>
>> if (unlikely(status < 0) || unlikely(!netif_running(ndev))) {
>> /* In dual emac mode check for all interfaces */

--
Regards,
Ivan Khoronzhuk

2018-07-27 19:54:20

by Ivan Khoronzhuk

[permalink] [raw]
Subject: Re: [PATCH net-next] net: ethernet: ti: cpsw: replace unnecessarily macroses on functions

On Fri, Jul 27, 2018 at 10:36:43PM +0300, Ivan Khoronzhuk wrote:
>On Fri, Jul 27, 2018 at 12:21:07PM -0700, Joe Perches wrote:
>>On Fri, 2018-07-27 at 22:13 +0300, Ivan Khoronzhuk wrote:
>>>Replace ugly macroses on functions.
>>
>>Careful, see below.
>>
>>>diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c
>>[]
>>>@@ -565,40 +565,40 @@ static const struct cpsw_stats cpsw_gstrings_ch_stats[] = {
>>> (func)(slave++, ##arg); \
>>> } while (0)
>>>
>>>-#define cpsw_dual_emac_src_port_detect(cpsw, status, ndev, skb) \
>>>- do { \
>>>- if (!cpsw->data.dual_emac) \
>>>- break; \
>>>- if (CPDMA_RX_SOURCE_PORT(status) == 1) { \
>>>- ndev = cpsw->slaves[0].ndev; \
>>>- skb->dev = ndev; \
>>>- } else if (CPDMA_RX_SOURCE_PORT(status) == 2) { \
>>>- ndev = cpsw->slaves[1].ndev; \
>>>- skb->dev = ndev; \
>>>- } \
>>>- } while (0)
>>>-#define cpsw_add_mcast(cpsw, priv, addr) \
>>>- do { \
>>>- if (cpsw->data.dual_emac) { \
>>>- struct cpsw_slave *slave = cpsw->slaves + \
>>>- priv->emac_port; \
>>>- int slave_port = cpsw_get_slave_port( \
>>>- slave->slave_num); \
>>>- cpsw_ale_add_mcast(cpsw->ale, addr, \
>>>- 1 << slave_port | ALE_PORT_HOST, \
>>>- ALE_VLAN, slave->port_vlan, 0); \
>>>- } else { \
>>>- cpsw_ale_add_mcast(cpsw->ale, addr, \
>>>- ALE_ALL_PORTS, \
>>>- 0, 0, 0); \
>>>- } \
>>>- } while (0)
>>>-
>>> static inline int cpsw_get_slave_port(u32 slave_num)
>>> {
>>> return slave_num + 1;
>>> }
>>>
>>>+static inline void cpsw_src_port_detect(struct cpsw_common *cpsw, int status,
>>>+ struct sk_buff *skb)
>>>+{
>>>+ if (!cpsw->data.dual_emac)
>>>+ return;
>>>+
>>>+ if (CPDMA_RX_SOURCE_PORT(status) == 1)
>>>+ skb->dev = cpsw->slaves[0].ndev;
>>>+ else if (CPDMA_RX_SOURCE_PORT(status) == 2)
>>>+ skb->dev = cpsw->slaves[1].ndev;
>>>+}
>>
>>perhaps better as a switch/case
>not better, it's shorter.
>
>>
>>>+
>>>+static void cpsw_add_mcast(struct cpsw_priv *priv, u8 *addr)
>>>+{
>>>+ struct cpsw_common *cpsw = priv->cpsw;
>>>+
>>>+ if (cpsw->data.dual_emac) {
>>>+ struct cpsw_slave *slave = cpsw->slaves + priv->emac_port;
>>>+ int slave_port = cpsw_get_slave_port(slave->slave_num);
>>>+
>>>+ cpsw_ale_add_mcast(cpsw->ale, addr,
>>>+ 1 << slave_port | ALE_PORT_HOST,
>>>+ ALE_VLAN, slave->port_vlan, 0);
>>>+ return;
>>>+ }
>>>+
>>>+ cpsw_ale_add_mcast(cpsw->ale, addr, ALE_ALL_PORTS, 0, 0, 0);
>>>+}
>>>+
>>> static void cpsw_set_promiscious(struct net_device *ndev, bool enable)
>>> {
>>> struct cpsw_common *cpsw = ndev_to_cpsw(ndev);
>>>@@ -706,7 +706,7 @@ static void cpsw_ndo_set_rx_mode(struct net_device *ndev)
>>>
>>> /* program multicast address list into ALE register */
>>> netdev_for_each_mc_addr(ha, ndev) {
>>>- cpsw_add_mcast(cpsw, priv, (u8 *)ha->addr);
>>>+ cpsw_add_mcast(priv, (u8 *)ha->addr);
>>> }
>>> }
>>> }
>>>@@ -801,7 +801,8 @@ static void cpsw_rx_handler(void *token, int len, int status)
>>> int ret = 0;
>>> struct cpsw_common *cpsw = ndev_to_cpsw(ndev);
>>>
>>>- cpsw_dual_emac_src_port_detect(cpsw, status, ndev, skb);
>>>+ cpsw_src_port_detect(cpsw, status, skb);
>>>+ ndev = skb->dev;
>>
>>This is not the same code as the new function
>>is not guaranteed to succeed or set skb->dev.
>Guaranteed by above skb->dev is initialized already.
>The function reflects previous macro.
>
>Even more, seems that here is duplication of ndev=skb->dev;
>It should be removed at init ), even if it 100% is optimized by complier.
>So guaranteed a little more then needed ), will send v2 with removed
>ndev = skb->dev at init if no objection.

But no, not duplicates.
It's used to get cpsw. So everyting is fine.
Patch should go as is.

>
>>
>>> if (unlikely(status < 0) || unlikely(!netif_running(ndev))) {
>>> /* In dual emac mode check for all interfaces */
>
>--
>Regards,
>Ivan Khoronzhuk

--
Regards,
Ivan Khoronzhuk

2018-07-27 20:05:42

by Joe Perches

[permalink] [raw]
Subject: Re: [PATCH net-next] net: ethernet: ti: cpsw: replace unnecessarily macroses on functions

On Fri, 2018-07-27 at 22:36 +0300, Ivan Khoronzhuk wrote:
> On Fri, Jul 27, 2018 at 12:21:07PM -0700, Joe Perches wrote:
> > On Fri, 2018-07-27 at 22:13 +0300, Ivan Khoronzhuk wrote:
> > > Replace ugly macroses on functions.
> >
> > Careful, see below.
> >
> > > diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c
> >
> > []
> > > @@ -565,40 +565,40 @@ static const struct cpsw_stats cpsw_gstrings_ch_stats[] = {
> > > (func)(slave++, ##arg); \
> > > } while (0)
> > >
> > > -#define cpsw_dual_emac_src_port_detect(cpsw, status, ndev, skb) \
> > > - do { \
> > > - if (!cpsw->data.dual_emac) \
> > > - break; \
> > > - if (CPDMA_RX_SOURCE_PORT(status) == 1) { \
> > > - ndev = cpsw->slaves[0].ndev; \
> > > - skb->dev = ndev; \
> > > - } else if (CPDMA_RX_SOURCE_PORT(status) == 2) { \
> > > - ndev = cpsw->slaves[1].ndev; \
> > > - skb->dev = ndev; \
> > > - } \
> > > - } while (0)
> > > -#define cpsw_add_mcast(cpsw, priv, addr) \
> > > - do { \
> > > - if (cpsw->data.dual_emac) { \
> > > - struct cpsw_slave *slave = cpsw->slaves + \
> > > - priv->emac_port; \
> > > - int slave_port = cpsw_get_slave_port( \
> > > - slave->slave_num); \
> > > - cpsw_ale_add_mcast(cpsw->ale, addr, \
> > > - 1 << slave_port | ALE_PORT_HOST, \
> > > - ALE_VLAN, slave->port_vlan, 0); \
> > > - } else { \
> > > - cpsw_ale_add_mcast(cpsw->ale, addr, \
> > > - ALE_ALL_PORTS, \
> > > - 0, 0, 0); \
> > > - } \
> > > - } while (0)
> > > -
> > > static inline int cpsw_get_slave_port(u32 slave_num)
> > > {
> > > return slave_num + 1;
> > > }
> > >
> > > +static inline void cpsw_src_port_detect(struct cpsw_common *cpsw, int status,
> > > + struct sk_buff *skb)
> > > +{
> > > + if (!cpsw->data.dual_emac)
> > > + return;
> > > +
> > > + if (CPDMA_RX_SOURCE_PORT(status) == 1)
> > > + skb->dev = cpsw->slaves[0].ndev;
> > > + else if (CPDMA_RX_SOURCE_PORT(status) == 2)
> > > + skb->dev = cpsw->slaves[1].ndev;
> > > +}
> >
> > perhaps better as a switch/case
>
> not better, it's shorter.

True for the source code but it compiles to more object code.

$ cat foo.c
struct cpsw_common {
struct {
int dual_emac;
} data;
struct {
int ndev;
} slaves[2];
};

struct sk_buff {
int dev;
};

#define CPDMA_RX_SOURCE_PORT(__status__) ((__status__ >> 16) & 0x7)

#if defined SWITCH

void foo(struct cpsw_common *cpsw, int status, struct sk_buff *skb)
{
if (!cpsw->data.dual_emac)
return;

switch (CPDMA_RX_SOURCE_PORT(status)) {
case 1:
skb->dev = cpsw->slaves[0].ndev;
break;
case 2:
skb->dev = cpsw->slaves[1].ndev;
break;
}
}

#else

void foo(struct cpsw_common *cpsw, int status, struct sk_buff *skb)
{
if (!cpsw->data.dual_emac)
return;

if (CPDMA_RX_SOURCE_PORT(status) == 1)
skb->dev = cpsw->slaves[0].ndev;
else if (CPDMA_RX_SOURCE_PORT(status) == 2)
skb->dev = cpsw->slaves[1].ndev;
}

#endif
$ gcc -c -O2 -DSWITCH foo.c
$ size foo.o
text data bss dec hex filename
94 0 0 94 5e foo.o
$ objdump -d foo.o

foo.o: file format elf64-x86-64


Disassembly of section .text:

0000000000000000 <foo>:
0: 8b 07 mov (%rdi),%eax
2: 85 c0 test %eax,%eax
4: 74 15 je 1b <foo+0x1b>
6: c1 fe 10 sar $0x10,%esi
9: 83 e6 07 and $0x7,%esi
c: 83 fe 01 cmp $0x1,%esi
f: 74 17 je 28 <foo+0x28>
11: 83 fe 02 cmp $0x2,%esi
14: 75 0a jne 20 <foo+0x20>
16: 8b 47 08 mov 0x8(%rdi),%eax
19: 89 02 mov %eax,(%rdx)
1b: f3 c3 repz retq
1d: 0f 1f 00 nopl (%rax)
20: f3 c3 repz retq
22: 66 0f 1f 44 00 00 nopw 0x0(%rax,%rax,1)
28: 8b 47 04 mov 0x4(%rdi),%eax
2b: 89 02 mov %eax,(%rdx)
2d: c3 retq
$ gcc -c -O2 foo.c
$ size foo.o
text data bss dec hex filename
102 0 0 102 66 foo.o
$ objdump -d foo.o

foo.o: file format elf64-x86-64


Disassembly of section .text:

0000000000000000 <foo>:
0: 8b 07 mov (%rdi),%eax
2: 85 c0 test %eax,%eax
4: 74 10 je 16 <foo+0x16>
6: c1 fe 10 sar $0x10,%esi
9: 83 e6 07 and $0x7,%esi
c: 83 fe 01 cmp $0x1,%esi
f: 74 0f je 20 <foo+0x20>
11: 83 fe 02 cmp $0x2,%esi
14: 74 1a je 30 <foo+0x30>
16: f3 c3 repz retq
18: 0f 1f 84 00 00 00 00 nopl 0x0(%rax,%rax,1)
1f: 00
20: 8b 47 04 mov 0x4(%rdi),%eax
23: 89 02 mov %eax,(%rdx)
25: c3 retq
26: 66 2e 0f 1f 84 00 00 nopw %cs:0x0(%rax,%rax,1)
2d: 00 00 00
30: 8b 47 08 mov 0x8(%rdi),%eax
33: 89 02 mov %eax,(%rdx)
35: c3 retq



2018-07-27 20:25:31

by Ivan Khoronzhuk

[permalink] [raw]
Subject: Re: [PATCH net-next] net: ethernet: ti: cpsw: replace unnecessarily macroses on functions

On Fri, Jul 27, 2018 at 01:04:22PM -0700, Joe Perches wrote:
>On Fri, 2018-07-27 at 22:36 +0300, Ivan Khoronzhuk wrote:
>> On Fri, Jul 27, 2018 at 12:21:07PM -0700, Joe Perches wrote:
>> > On Fri, 2018-07-27 at 22:13 +0300, Ivan Khoronzhuk wrote:
>> > > Replace ugly macroses on functions.
>> >
>> > Careful, see below.
>> >
>> > > diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c
>> >
>> > []
>> > > @@ -565,40 +565,40 @@ static const struct cpsw_stats cpsw_gstrings_ch_stats[] = {
>> > > (func)(slave++, ##arg); \
>> > > } while (0)
>> > >
>> > > -#define cpsw_dual_emac_src_port_detect(cpsw, status, ndev, skb) \
>> > > - do { \
>> > > - if (!cpsw->data.dual_emac) \
>> > > - break; \
>> > > - if (CPDMA_RX_SOURCE_PORT(status) == 1) { \
>> > > - ndev = cpsw->slaves[0].ndev; \
>> > > - skb->dev = ndev; \
>> > > - } else if (CPDMA_RX_SOURCE_PORT(status) == 2) { \
>> > > - ndev = cpsw->slaves[1].ndev; \
>> > > - skb->dev = ndev; \
>> > > - } \
>> > > - } while (0)
>> > > -#define cpsw_add_mcast(cpsw, priv, addr) \
>> > > - do { \
>> > > - if (cpsw->data.dual_emac) { \
>> > > - struct cpsw_slave *slave = cpsw->slaves + \
>> > > - priv->emac_port; \
>> > > - int slave_port = cpsw_get_slave_port( \
>> > > - slave->slave_num); \
>> > > - cpsw_ale_add_mcast(cpsw->ale, addr, \
>> > > - 1 << slave_port | ALE_PORT_HOST, \
>> > > - ALE_VLAN, slave->port_vlan, 0); \
>> > > - } else { \
>> > > - cpsw_ale_add_mcast(cpsw->ale, addr, \
>> > > - ALE_ALL_PORTS, \
>> > > - 0, 0, 0); \
>> > > - } \
>> > > - } while (0)
>> > > -
>> > > static inline int cpsw_get_slave_port(u32 slave_num)
>> > > {
>> > > return slave_num + 1;
>> > > }
>> > >
>> > > +static inline void cpsw_src_port_detect(struct cpsw_common *cpsw, int status,
>> > > + struct sk_buff *skb)
>> > > +{
>> > > + if (!cpsw->data.dual_emac)
>> > > + return;
>> > > +
>> > > + if (CPDMA_RX_SOURCE_PORT(status) == 1)
>> > > + skb->dev = cpsw->slaves[0].ndev;
>> > > + else if (CPDMA_RX_SOURCE_PORT(status) == 2)
>> > > + skb->dev = cpsw->slaves[1].ndev;
>> > > +}
>> >
>> > perhaps better as a switch/case
>>
>> not better, it's shorter.
>
>True for the source code but it compiles to more object code.
>
>$ cat foo.c
>struct cpsw_common {
> struct {
> int dual_emac;
> } data;
> struct {
> int ndev;
> } slaves[2];
>};
>
>struct sk_buff {
> int dev;
>};
>
>#define CPDMA_RX_SOURCE_PORT(__status__) ((__status__ >> 16) & 0x7)
>
>#if defined SWITCH
>
>void foo(struct cpsw_common *cpsw, int status, struct sk_buff *skb)
>{
> if (!cpsw->data.dual_emac)
> return;
>
> switch (CPDMA_RX_SOURCE_PORT(status)) {
> case 1:
> skb->dev = cpsw->slaves[0].ndev;
> break;
> case 2:
> skb->dev = cpsw->slaves[1].ndev;
> break;
> }
>}
>
>#else
>
>void foo(struct cpsw_common *cpsw, int status, struct sk_buff *skb)
>{
> if (!cpsw->data.dual_emac)
> return;
>
> if (CPDMA_RX_SOURCE_PORT(status) == 1)
> skb->dev = cpsw->slaves[0].ndev;
> else if (CPDMA_RX_SOURCE_PORT(status) == 2)
> skb->dev = cpsw->slaves[1].ndev;
>}
>
>#endif
>$ gcc -c -O2 -DSWITCH foo.c
>$ size foo.o
> text data bss dec hex filename
> 94 0 0 94 5e foo.o
>$ objdump -d foo.o
>
>foo.o: file format elf64-x86-64
>
>
>Disassembly of section .text:
>
>0000000000000000 <foo>:
> 0: 8b 07 mov (%rdi),%eax
> 2: 85 c0 test %eax,%eax
> 4: 74 15 je 1b <foo+0x1b>
> 6: c1 fe 10 sar $0x10,%esi
> 9: 83 e6 07 and $0x7,%esi
> c: 83 fe 01 cmp $0x1,%esi
> f: 74 17 je 28 <foo+0x28>
> 11: 83 fe 02 cmp $0x2,%esi
> 14: 75 0a jne 20 <foo+0x20>
> 16: 8b 47 08 mov 0x8(%rdi),%eax
> 19: 89 02 mov %eax,(%rdx)
> 1b: f3 c3 repz retq
> 1d: 0f 1f 00 nopl (%rax)
> 20: f3 c3 repz retq
> 22: 66 0f 1f 44 00 00 nopw 0x0(%rax,%rax,1)
> 28: 8b 47 04 mov 0x4(%rdi),%eax
> 2b: 89 02 mov %eax,(%rdx)
> 2d: c3 retq
>$ gcc -c -O2 foo.c
>$ size foo.o
> text data bss dec hex filename
> 102 0 0 102 66 foo.o
>$ objdump -d foo.o
>
>foo.o: file format elf64-x86-64
>
>
>Disassembly of section .text:
>
>0000000000000000 <foo>:
> 0: 8b 07 mov (%rdi),%eax
> 2: 85 c0 test %eax,%eax
> 4: 74 10 je 16 <foo+0x16>
> 6: c1 fe 10 sar $0x10,%esi
> 9: 83 e6 07 and $0x7,%esi
> c: 83 fe 01 cmp $0x1,%esi
> f: 74 0f je 20 <foo+0x20>
> 11: 83 fe 02 cmp $0x2,%esi
> 14: 74 1a je 30 <foo+0x30>
> 16: f3 c3 repz retq
> 18: 0f 1f 84 00 00 00 00 nopl 0x0(%rax,%rax,1)
> 1f: 00
> 20: 8b 47 04 mov 0x4(%rdi),%eax
> 23: 89 02 mov %eax,(%rdx)
> 25: c3 retq
> 26: 66 2e 0f 1f 84 00 00 nopw %cs:0x0(%rax,%rax,1)
> 2d: 00 00 00
> 30: 8b 47 08 mov 0x8(%rdi),%eax
> 33: 89 02 mov %eax,(%rdx)
> 35: c3 retq
>
>

This driver, mainly used for ARM

For ARM, situation a little bit different:
$ arm-linux-gnueabihf-gcc -c -O2 -DSWITCH foo.c
$ size foo.o
text data bss dec hex filename
32 0 0 32 20 foo.o

$ arm-linux-gnueabihf-objdump -d foo.o

foo.o: file format elf32-littlearm


Disassembly of section .text:

00000000 <foo>:
0: 6803 ldr r3, [r0, #0]
2: b143 cbz r3, 16 <foo+0x16>
4: f3c1 4102 ubfx r1, r1, #16, #3
8: 2901 cmp r1, #1
a: d005 beq.n 18 <foo+0x18>
c: 2902 cmp r1, #2
e: d000 beq.n 12 <foo+0x12>
10: 4770 bx lr
12: 6883 ldr r3, [r0, #8]
14: 6013 str r3, [r2, #0]
16: 4770 bx lr
18: 6843 ldr r3, [r0, #4]
1a: 6013 str r3, [r2, #0]
1c: 4770 bx lr
1e: bf00 nop



$ arm-linux-gnueabihf-gcc -c -O2 foo.c
$ size foo.o
text data bss dec hex filename
28 0 0 28 1c foo.o

$ arm-linux-gnueabihf-objdump -d foo.o

foo.o: file format elf32-littlearm


Disassembly of section .text:

00000000 <foo>:
0: 6803 ldr r3, [r0, #0]
2: b13b cbz r3, 14 <foo+0x14>
4: f3c1 4102 ubfx r1, r1, #16, #3
8: 2901 cmp r1, #1
a: d004 beq.n 16 <foo+0x16>
c: 2902 cmp r1, #2
e: bf04 itt eq
10: 6883 ldreq r3, [r0, #8]
12: 6013 streq r3, [r2, #0]
14: 4770 bx lr
16: 6843 ldr r3, [r0, #4]
18: 6013 str r3, [r2, #0]
1a: 4770 bx lr

So, it's shorter.

--
Regards,
Ivan Khoronzhuk

2018-07-27 20:30:59

by Joe Perches

[permalink] [raw]
Subject: Re: [PATCH net-next] net: ethernet: ti: cpsw: replace unnecessarily macroses on functions

On Fri, 2018-07-27 at 23:23 +0300, Ivan Khoronzhuk wrote:
> For ARM, situation a little bit different:
> $ arm-linux-gnueabihf-gcc -c -O2 -DSWITCH foo.c
> $ size foo.o
> text data bss dec hex filename
> 32 0 0 32 20 foo.o
[]
> $ arm-linux-gnueabihf-gcc -c -O2 foo.c
> $ size foo.o
> text data bss dec hex filename
> 28 0 0 28 1c foo.o
[]
> So, it's shorter.

No worries.

I was kinda surprised the object code wasn't identical anyway.

cheers, Joe

2018-07-27 20:33:14

by Andrew Lunn

[permalink] [raw]
Subject: Re: [PATCH net-next] net: ethernet: ti: cpsw: replace unnecessarily macroses on functions

> +static inline void cpsw_src_port_detect(struct cpsw_common *cpsw, int status,
> + struct sk_buff *skb)

Please don't use inline. Let the compiler decide.

Andrew

2018-07-27 20:51:06

by Ivan Khoronzhuk

[permalink] [raw]
Subject: Re: [PATCH net-next] net: ethernet: ti: cpsw: replace unnecessarily macroses on functions

On Fri, Jul 27, 2018 at 10:32:03PM +0200, Andrew Lunn wrote:
>> +static inline void cpsw_src_port_detect(struct cpsw_common *cpsw, int status,
>> + struct sk_buff *skb)
>
>Please don't use inline. Let the compiler decide.
>
> Andrew

Corrected in v2

--
Regards,
Ivan Khoronzhuk