2015-07-09 08:14:00

by Vineet Gupta

[permalink] [raw]
Subject: [PATCH 0/3] atomic_or() related changes

Hi,

This started off as an effort to convert a cmpxchg based loop in arc/kernel/smp.c
to an API which is more LLOCK/SCOND friendly.

e.g.
do {
new = old = ACCESS_ONCE(*ipi_data_ptr);
new |= 1U << msg;
} while (cmpxchg(ipi_data_ptr, old, new) != old);

The generated code is horrible. There are 2 useless branches here and a
LD/LLOCK to same address all inside a loop.

8015cefc: ld_s r2,[r3,0]
8015cefe: or r5,r2,r1
8015cf02: llock r4,[r3]
8015cf06: brne r4,r2,8015cf12
8015cf0a: scond r5,[r3]
8015cf0e: bnz 8015cf02
8015cf12: brne r2,r4,8015cefc

An atomic_or() kind of API is better suited to generate something like below

8015cf02: llock r4,[r3]
8015cf06: or r5,r2,r1
8015cf0a: scond r5,[r3]
8015cf0e: bnz 8015cf02

Although this doesn't work for the specific instance I wanted to fix as
ipi_data_ptr is not atomic_t, I did run into a few things which could be
improved, hence this series.

Compile tested on ARC, ARM, x86.

I do have some concern about mixing long and int on 64 bit arch, which I've
captured inline in patch 2/3. It is most likely a lack of understand on my
part, but worth asking..

Thx,
-Vineet

Vineet Gupta (3):
asm-generic/atomic.h: ARCH_HAS_ATOMIC_OR -> CONFIG_ARCH_HAS_ATOMIC_OR
brcmfmac: dhd_sdio.c: use existing atomic_or primitive
ARC: provide atomic_or() and define ARCH_HAS_ATOMIC_OR

arch/arc/include/asm/atomic.h | 9 +++++++++
drivers/net/wireless/brcm80211/brcmfmac/sdio.c | 13 ++-----------
include/asm-generic/atomic.h | 2 +-
include/linux/atomic.h | 4 ++--
4 files changed, 14 insertions(+), 14 deletions(-)

--
1.9.1


2015-07-09 08:14:18

by Vineet Gupta

[permalink] [raw]
Subject: [PATCH 1/3] asm-generic/atomic.h: ARCH_HAS_ATOMIC_OR -> CONFIG_ARCH_HAS_ATOMIC_OR

Since this is not backed by a Kconfig option, remove CONFIG_ prefix

Cc: Arnd Bergmann <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Vineet Gupta <[email protected]>
---
include/asm-generic/atomic.h | 2 +-
include/linux/atomic.h | 4 ++--
2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/include/asm-generic/atomic.h b/include/asm-generic/atomic.h
index 1973ad2b13f4..1a1cdab6e702 100644
--- a/include/asm-generic/atomic.h
+++ b/include/asm-generic/atomic.h
@@ -104,7 +104,7 @@ ATOMIC_OP(and, &)
#endif

#ifndef atomic_set_mask
-#define CONFIG_ARCH_HAS_ATOMIC_OR
+#define ARCH_HAS_ATOMIC_OR
ATOMIC_OP(or, |)
#define atomic_set_mask(i, v) atomic_or((i), (v))
#endif
diff --git a/include/linux/atomic.h b/include/linux/atomic.h
index 5b08a8540ecf..195881eec33e 100644
--- a/include/linux/atomic.h
+++ b/include/linux/atomic.h
@@ -111,7 +111,7 @@ static inline int atomic_dec_if_positive(atomic_t *v)
}
#endif

-#ifndef CONFIG_ARCH_HAS_ATOMIC_OR
+#ifndef ARCH_HAS_ATOMIC_OR
static inline void atomic_or(int i, atomic_t *v)
{
int old;
@@ -122,7 +122,7 @@ static inline void atomic_or(int i, atomic_t *v)
new = old | i;
} while (atomic_cmpxchg(v, old, new) != old);
}
-#endif /* #ifndef CONFIG_ARCH_HAS_ATOMIC_OR */
+#endif /* #ifndef ARCH_HAS_ATOMIC_OR */

#include <asm-generic/atomic-long.h>
#ifdef CONFIG_GENERIC_ATOMIC64
--
1.9.1

2015-07-09 08:14:39

by Vineet Gupta

[permalink] [raw]
Subject: [PATCH 2/3] brcmfmac: dhd_sdio.c: use existing atomic_or primitive

There's already a generic implementation so use that instead.
---
I'm not sure if the driver usage of atomic_or?() is correct in terms of
storage size of @val for 64 bit arches.

Assuming LP64 programming model for linux on say x86_64: atomic_or()
callers in this driver use long (sana 64 bit) storage and pass it to
atomic_orr/atomic_or which downcasts it to 32 bits. Is that OK ?
---
Cc: Brett Rudley <[email protected]>
Cc: Arend van Spriel <[email protected]>
Cc: "Franky (Zhenhui) Lin" <[email protected]>
Cc: Hante Meuleman <[email protected]>
Cc: Kalle Valo <[email protected]>
Cc: Pieter-Paul Giesberts <[email protected]>
Cc: Daniel Kim <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: Peter Zijlstra <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Vineet Gupta <[email protected]>

Signed-off-by: Vineet Gupta <[email protected]>
---
drivers/net/wireless/brcm80211/brcmfmac/sdio.c | 13 ++-----------
1 file changed, 2 insertions(+), 11 deletions(-)

diff --git a/drivers/net/wireless/brcm80211/brcmfmac/sdio.c b/drivers/net/wireless/brcm80211/brcmfmac/sdio.c
index d36f5f3d931b..f990e3d0e696 100644
--- a/drivers/net/wireless/brcm80211/brcmfmac/sdio.c
+++ b/drivers/net/wireless/brcm80211/brcmfmac/sdio.c
@@ -2564,15 +2564,6 @@ static inline void brcmf_sdio_clrintr(struct brcmf_sdio *bus)
}
}

-static void atomic_orr(int val, atomic_t *v)
-{
- int old_val;
-
- old_val = atomic_read(v);
- while (atomic_cmpxchg(v, old_val, val | old_val) != old_val)
- old_val = atomic_read(v);
-}
-
static int brcmf_sdio_intr_rstatus(struct brcmf_sdio *bus)
{
struct brcmf_core *buscore;
@@ -2595,7 +2586,7 @@ static int brcmf_sdio_intr_rstatus(struct brcmf_sdio *bus)
if (val) {
brcmf_sdiod_regwl(bus->sdiodev, addr, val, &ret);
bus->sdcnt.f1regdata++;
- atomic_orr(val, &bus->intstatus);
+ atomic_or(val, &bus->intstatus);
}

return ret;
@@ -2712,7 +2703,7 @@ static void brcmf_sdio_dpc(struct brcmf_sdio *bus)

/* Keep still-pending events for next scheduling */
if (intstatus)
- atomic_orr(intstatus, &bus->intstatus);
+ atomic_or(intstatus, &bus->intstatus);

brcmf_sdio_clrintr(bus);

--
1.9.1

2015-07-09 08:14:58

by Vineet Gupta

[permalink] [raw]
Subject: [PATCH 3/3] ARC: provide atomic_or() and define ARCH_HAS_ATOMIC_OR

Cc: Peter Zijlstra <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Vineet Gupta <[email protected]>
---
arch/arc/include/asm/atomic.h | 9 +++++++++
1 file changed, 9 insertions(+)

diff --git a/arch/arc/include/asm/atomic.h b/arch/arc/include/asm/atomic.h
index 03484cb4d16d..fab27dbc562b 100644
--- a/arch/arc/include/asm/atomic.h
+++ b/arch/arc/include/asm/atomic.h
@@ -141,10 +141,19 @@ static inline int atomic_##op##_return(int i, atomic_t *v) \
ATOMIC_OP(op, c_op, asm_op) \
ATOMIC_OP_RETURN(op, c_op, asm_op)

+/* atomic_add(), atomic_add_return() */
ATOMIC_OPS(add, +=, add)
+
+/* atomic_sub(), atomic_sub_return() */
ATOMIC_OPS(sub, -=, sub)
+
+/* atomic_and() */
ATOMIC_OP(and, &=, and)

+#define ARCH_HAS_ATOMIC_OR
+/* atomic_or() */
+ATOMIC_OP(or, |=, or)
+
#define atomic_clear_mask(mask, v) atomic_and(~(mask), (v))

#undef ATOMIC_OPS
--
1.9.1

2015-07-09 12:31:41

by Peter Zijlstra

[permalink] [raw]
Subject: Re: [PATCH 0/3] atomic_or() related changes



I see what you did there.. gimme a few more hours, I'll finish what I
have and stuff it through the build bot.

I've just not managed to finish tile, but did do frv this time.

2015-07-09 13:05:38

by Vineet Gupta

[permalink] [raw]
Subject: Re: [PATCH 0/3] atomic_or() related changes

On Thursday 09 July 2015 06:01 PM, Peter Zijlstra wrote:
> I've just not managed to finish tile, but did do frv this time.

Not sure what you mean - are you also doing a similar series which extends
atomic_or to other arches too which will probably we simpler now given ur earlier
macro-fication of this code !

-vineet

2015-07-09 13:20:48

by Peter Zijlstra

[permalink] [raw]
Subject: Re: [PATCH 0/3] atomic_or() related changes

On Thu, Jul 09, 2015 at 01:05:25PM +0000, Vineet Gupta wrote:
> On Thursday 09 July 2015 06:01 PM, Peter Zijlstra wrote:
> > I've just not managed to finish tile, but did do frv this time.
>
> Not sure what you mean - are you also doing a similar series which extends
> atomic_or to other arches too which will probably we simpler now given ur earlier
> macro-fication of this code !

Yes, one I started a long time ago, I got two rounds of arch/* atomic
cleanups in already, but never got around to actually finishing it.

The next round is almost done, only tile is missing.

My current series is here:

https://git.kernel.org/cgit/linux/kernel/git/peterz/queue.git/log/?h=locking/arch

And I just found there's a bisection fail in there, so let me go fix
that before posting.

Once I got this sorted, there's maybe one more round left.

2015-07-09 18:25:36

by Arend van Spriel

[permalink] [raw]
Subject: Re: [PATCH 2/3] brcmfmac: dhd_sdio.c: use existing atomic_or primitive

On 07/09/2015 10:13 AM, Vineet Gupta wrote:
> There's already a generic implementation so use that instead.

There is or there was? If there is now I am fine with this patch, but if
it already was there the author might have had a reason for adding a
local function and I would like to hear that reason.

> ---
> I'm not sure if the driver usage of atomic_or?() is correct in terms of
> storage size of @val for 64 bit arches.
>
> Assuming LP64 programming model for linux on say x86_64: atomic_or()
> callers in this driver use long (sana 64 bit) storage and pass it to
> atomic_orr/atomic_or which downcasts it to 32 bits. Is that OK ?

The function is used with 32bit register value from the device so I
think it is ok.

Regards,
Arend

> ---
> Cc: Brett Rudley <[email protected]>
> Cc: Arend van Spriel <[email protected]>
> Cc: "Franky (Zhenhui) Lin" <[email protected]>
> Cc: Hante Meuleman <[email protected]>
> Cc: Kalle Valo <[email protected]>
> Cc: Pieter-Paul Giesberts <[email protected]>
> Cc: Daniel Kim <[email protected]>
> Cc: [email protected]
> Cc: [email protected]
> Cc: Peter Zijlstra <[email protected]>
> Cc: Ingo Molnar <[email protected]>
> Cc: [email protected]
> Cc: [email protected]
> Cc: [email protected]
> Signed-off-by: Vineet Gupta <[email protected]>
>
> Signed-off-by: Vineet Gupta <[email protected]>
> ---
> drivers/net/wireless/brcm80211/brcmfmac/sdio.c | 13 ++-----------
> 1 file changed, 2 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/net/wireless/brcm80211/brcmfmac/sdio.c b/drivers/net/wireless/brcm80211/brcmfmac/sdio.c
> index d36f5f3d931b..f990e3d0e696 100644
> --- a/drivers/net/wireless/brcm80211/brcmfmac/sdio.c
> +++ b/drivers/net/wireless/brcm80211/brcmfmac/sdio.c
> @@ -2564,15 +2564,6 @@ static inline void brcmf_sdio_clrintr(struct brcmf_sdio *bus)
> }
> }
>
> -static void atomic_orr(int val, atomic_t *v)
> -{
> - int old_val;
> -
> - old_val = atomic_read(v);
> - while (atomic_cmpxchg(v, old_val, val | old_val) != old_val)
> - old_val = atomic_read(v);
> -}
> -
> static int brcmf_sdio_intr_rstatus(struct brcmf_sdio *bus)
> {
> struct brcmf_core *buscore;
> @@ -2595,7 +2586,7 @@ static int brcmf_sdio_intr_rstatus(struct brcmf_sdio *bus)
> if (val) {
> brcmf_sdiod_regwl(bus->sdiodev, addr, val, &ret);
> bus->sdcnt.f1regdata++;
> - atomic_orr(val, &bus->intstatus);
> + atomic_or(val, &bus->intstatus);
> }
>
> return ret;
> @@ -2712,7 +2703,7 @@ static void brcmf_sdio_dpc(struct brcmf_sdio *bus)
>
> /* Keep still-pending events for next scheduling */
> if (intstatus)
> - atomic_orr(intstatus, &bus->intstatus);
> + atomic_or(intstatus, &bus->intstatus);
>
> brcmf_sdio_clrintr(bus);
>
>

2015-07-09 18:31:29

by Arend van Spriel

[permalink] [raw]
Subject: Re: [PATCH 2/3] brcmfmac: dhd_sdio.c: use existing atomic_or primitive

On 07/09/2015 08:25 PM, Arend van Spriel wrote:
> On 07/09/2015 10:13 AM, Vineet Gupta wrote:
>> There's already a generic implementation so use that instead.
>
> There is or there was? If there is now I am fine with this patch, but if
> it already was there the author might have had a reason for adding a
> local function and I would like to hear that reason.

Nevermind. Just noticed you are proposing the generic implementation in
this series. Currently on vacation and want to discuss with Hante about
this change.

Regards,
Arend

>> ---
>> I'm not sure if the driver usage of atomic_or?() is correct in terms of
>> storage size of @val for 64 bit arches.
>>
>> Assuming LP64 programming model for linux on say x86_64: atomic_or()
>> callers in this driver use long (sana 64 bit) storage and pass it to
>> atomic_orr/atomic_or which downcasts it to 32 bits. Is that OK ?
>
> The function is used with 32bit register value from the device so I
> think it is ok.
>
> Regards,
> Arend
>
>> ---
>> Cc: Brett Rudley <[email protected]>
>> Cc: Arend van Spriel <[email protected]>
>> Cc: "Franky (Zhenhui) Lin" <[email protected]>
>> Cc: Hante Meuleman <[email protected]>
>> Cc: Kalle Valo <[email protected]>
>> Cc: Pieter-Paul Giesberts <[email protected]>
>> Cc: Daniel Kim <[email protected]>
>> Cc: [email protected]
>> Cc: [email protected]
>> Cc: Peter Zijlstra <[email protected]>
>> Cc: Ingo Molnar <[email protected]>
>> Cc: [email protected]
>> Cc: [email protected]
>> Cc: [email protected]
>> Signed-off-by: Vineet Gupta <[email protected]>
>>
>> Signed-off-by: Vineet Gupta <[email protected]>
>> ---
>> drivers/net/wireless/brcm80211/brcmfmac/sdio.c | 13 ++-----------
>> 1 file changed, 2 insertions(+), 11 deletions(-)
>>
>> diff --git a/drivers/net/wireless/brcm80211/brcmfmac/sdio.c
>> b/drivers/net/wireless/brcm80211/brcmfmac/sdio.c
>> index d36f5f3d931b..f990e3d0e696 100644
>> --- a/drivers/net/wireless/brcm80211/brcmfmac/sdio.c
>> +++ b/drivers/net/wireless/brcm80211/brcmfmac/sdio.c
>> @@ -2564,15 +2564,6 @@ static inline void brcmf_sdio_clrintr(struct
>> brcmf_sdio *bus)
>> }
>> }
>>
>> -static void atomic_orr(int val, atomic_t *v)
>> -{
>> - int old_val;
>> -
>> - old_val = atomic_read(v);
>> - while (atomic_cmpxchg(v, old_val, val | old_val) != old_val)
>> - old_val = atomic_read(v);
>> -}
>> -
>> static int brcmf_sdio_intr_rstatus(struct brcmf_sdio *bus)
>> {
>> struct brcmf_core *buscore;
>> @@ -2595,7 +2586,7 @@ static int brcmf_sdio_intr_rstatus(struct
>> brcmf_sdio *bus)
>> if (val) {
>> brcmf_sdiod_regwl(bus->sdiodev, addr, val, &ret);
>> bus->sdcnt.f1regdata++;
>> - atomic_orr(val, &bus->intstatus);
>> + atomic_or(val, &bus->intstatus);
>> }
>>
>> return ret;
>> @@ -2712,7 +2703,7 @@ static void brcmf_sdio_dpc(struct brcmf_sdio *bus)
>>
>> /* Keep still-pending events for next scheduling */
>> if (intstatus)
>> - atomic_orr(intstatus, &bus->intstatus);
>> + atomic_or(intstatus, &bus->intstatus);
>>
>> brcmf_sdio_clrintr(bus);
>>
>>
>

2015-07-09 19:57:45

by Peter Zijlstra

[permalink] [raw]
Subject: Re: [PATCH 2/3] brcmfmac: dhd_sdio.c: use existing atomic_or primitive

On Thu, Jul 09, 2015 at 08:31:16PM +0200, Arend van Spriel wrote:
> >There is or there was? If there is now I am fine with this patch, but if
> >it already was there the author might have had a reason for adding a
> >local function and I would like to hear that reason.
>
> Nevermind. Just noticed you are proposing the generic implementation in this
> series. Currently on vacation and want to discuss with Hante about this
> change.

No there is one in linux/atomic.h, he just renamed the #ifdef guard and
provided a 'sane' implementation for his arch.

2015-07-10 04:50:22

by Vineet Gupta

[permalink] [raw]
Subject: Re: [PATCH 2/3] brcmfmac: dhd_sdio.c: use existing atomic_or primitive

On Thursday 09 July 2015 11:55 PM, Arend van Spriel wrote:
> On 07/09/2015 10:13 AM, Vineet Gupta wrote:
>> > There's already a generic implementation so use that instead.
> There is or there was? If there is now I am fine with this patch, but if
> it already was there the author might have had a reason for adding a
> local function and I would like to hear that reason.
>

atomic_orr() was introduced to this driver with

2014-03-06 5cbb9c285bdc brcmfmac: Use atomic functions for intstatus update.

as it seems atomic_set_mask() was not available cross arch. And atomic_or() in
generic code was indeed introduced after that

2014-04-23 560cb12a4080 locking,arch: Rewrite generic atomic support

Hence likely the reason author went with home grown atomic_orr()

-Vineet

2015-07-10 09:05:14

by Arend van Spriel

[permalink] [raw]
Subject: Re: [PATCH 2/3] brcmfmac: dhd_sdio.c: use existing atomic_or primitive

On 07/10/2015 06:49 AM, Vineet Gupta wrote:
> On Thursday 09 July 2015 11:55 PM, Arend van Spriel wrote:
>> On 07/09/2015 10:13 AM, Vineet Gupta wrote:
>>>> There's already a generic implementation so use that instead.
>> There is or there was? If there is now I am fine with this patch, but if
>> it already was there the author might have had a reason for adding a
>> local function and I would like to hear that reason.
>>
>
> atomic_orr() was introduced to this driver with
>
> 2014-03-06 5cbb9c285bdc brcmfmac: Use atomic functions for intstatus update.
>
> as it seems atomic_set_mask() was not available cross arch. And atomic_or() in
> generic code was indeed introduced after that
>
> 2014-04-23 560cb12a4080 locking,arch: Rewrite generic atomic support
>
> Hence likely the reason author went with home grown atomic_orr()

Hi Vineet

Thanks for looking into the timeline. Will look into it and let you know.

Regards,
Arend

> -Vineet
>

2015-07-24 17:03:09

by Kalle Valo

[permalink] [raw]
Subject: Re: [PATCH 2/3] brcmfmac: dhd_sdio.c: use existing atomic_or primitive

Vineet Gupta <[email protected]> writes:

> There's already a generic implementation so use that instead.
> ---
> I'm not sure if the driver usage of atomic_or?() is correct in terms of
> storage size of @val for 64 bit arches.
>
> Assuming LP64 programming model for linux on say x86_64: atomic_or()
> callers in this driver use long (sana 64 bit) storage and pass it to
> atomic_orr/atomic_or which downcasts it to 32 bits. Is that OK ?
> ---
> Cc: Brett Rudley <[email protected]>
> Cc: Arend van Spriel <[email protected]>
> Cc: "Franky (Zhenhui) Lin" <[email protected]>
> Cc: Hante Meuleman <[email protected]>
> Cc: Kalle Valo <[email protected]>
> Cc: Pieter-Paul Giesberts <[email protected]>
> Cc: Daniel Kim <[email protected]>
> Cc: [email protected]
> Cc: [email protected]
> Cc: Peter Zijlstra <[email protected]>
> Cc: Ingo Molnar <[email protected]>
> Cc: [email protected]
> Cc: [email protected]
> Cc: [email protected]
> Signed-off-by: Vineet Gupta <[email protected]>
>
> Signed-off-by: Vineet Gupta <[email protected]>

What's the plan with this patch? Should I take it to my
wireless-drivers-next tree or will someone else take it?

--
Kalle Valo

2015-07-24 17:22:16

by Vineet Gupta

[permalink] [raw]
Subject: Re: [PATCH 2/3] brcmfmac: dhd_sdio.c: use existing atomic_or primitive

On Friday 24 July 2015 08:02 PM, Kalle Valo wrote:
> Vineet Gupta <[email protected]> writes:
>
>> > There's already a generic implementation so use that instead.
>> > ---
>> > I'm not sure if the driver usage of atomic_or?() is correct in terms of
>> > storage size of @val for 64 bit arches.
>> >
>> > Assuming LP64 programming model for linux on say x86_64: atomic_or()
>> > callers in this driver use long (sana 64 bit) storage and pass it to
>> > atomic_orr/atomic_or which downcasts it to 32 bits. Is that OK ?
>> > ---
>> > Cc: Brett Rudley <[email protected]>
>> > Cc: Arend van Spriel <[email protected]>
>> > Cc: "Franky (Zhenhui) Lin" <[email protected]>
>> > Cc: Hante Meuleman <[email protected]>
>> > Cc: Kalle Valo <[email protected]>
>> > Cc: Pieter-Paul Giesberts <[email protected]>
>> > Cc: Daniel Kim <[email protected]>
>> > Cc: [email protected]
>> > Cc: [email protected]
>> > Cc: Peter Zijlstra <[email protected]>
>> > Cc: Ingo Molnar <[email protected]>
>> > Cc: [email protected]
>> > Cc: [email protected]
>> > Cc: [email protected]
>> > Signed-off-by: Vineet Gupta <[email protected]>
>> >
>> > Signed-off-by: Vineet Gupta <[email protected]>
> What's the plan with this patch? Should I take it to my
> wireless-drivers-next tree or will someone else take it?


Per last discussion on this topic, Arend wanted to discuss abt this with Hante.
I'm not taking it anyways so feel free to pick it up if you want !

-Vineet

2015-07-26 11:12:47

by Arend van Spriel

[permalink] [raw]
Subject: Re: [PATCH 2/3] brcmfmac: dhd_sdio.c: use existing atomic_or primitive

On 07/24/2015 07:22 PM, Vineet Gupta wrote:
> On Friday 24 July 2015 08:02 PM, Kalle Valo wrote:
>> Vineet Gupta <[email protected]> writes:
>>
>>>> There's already a generic implementation so use that instead.
>>>> ---
>>>> I'm not sure if the driver usage of atomic_or?() is correct in terms of
>>>> storage size of @val for 64 bit arches.
>>>>
>>>> Assuming LP64 programming model for linux on say x86_64: atomic_or()
>>>> callers in this driver use long (sana 64 bit) storage and pass it to
>>>> atomic_orr/atomic_or which downcasts it to 32 bits. Is that OK ?
>>>> ---
>>>> Cc: Brett Rudley <[email protected]>
>>>> Cc: Arend van Spriel <[email protected]>
>>>> Cc: "Franky (Zhenhui) Lin" <[email protected]>
>>>> Cc: Hante Meuleman <[email protected]>
>>>> Cc: Kalle Valo <[email protected]>
>>>> Cc: Pieter-Paul Giesberts <[email protected]>
>>>> Cc: Daniel Kim <[email protected]>
>>>> Cc: [email protected]
>>>> Cc: [email protected]
>>>> Cc: Peter Zijlstra <[email protected]>
>>>> Cc: Ingo Molnar <[email protected]>
>>>> Cc: [email protected]
>>>> Cc: [email protected]
>>>> Cc: [email protected]
>>>> Signed-off-by: Vineet Gupta <[email protected]>
>>>>
>>>> Signed-off-by: Vineet Gupta <[email protected]>
>> What's the plan with this patch? Should I take it to my
>> wireless-drivers-next tree or will someone else take it?
>
>
> Per last discussion on this topic, Arend wanted to discuss abt this with Hante.
> I'm not taking it anyways so feel free to pick it up if you want !

Well, that was before your "timeline" clarification about the generic
function. One what tree is this patch based?

Regards,
Arend

2015-07-27 10:08:54

by Kalle Valo

[permalink] [raw]
Subject: Re: [PATCH 2/3] brcmfmac: dhd_sdio.c: use existing atomic_or primitive

Arend van Spriel <[email protected]> writes:

> On 07/24/2015 07:22 PM, Vineet Gupta wrote:
>> On Friday 24 July 2015 08:02 PM, Kalle Valo wrote:
>>> Vineet Gupta <[email protected]> writes:
>>>
>>>>> There's already a generic implementation so use that instead.
>>>>> ---
>>>>> I'm not sure if the driver usage of atomic_or?() is correct in terms of
>>>>> storage size of @val for 64 bit arches.
>>>>>
>>>>> Assuming LP64 programming model for linux on say x86_64: atomic_or()
>>>>> callers in this driver use long (sana 64 bit) storage and pass it to
>>>>> atomic_orr/atomic_or which downcasts it to 32 bits. Is that OK ?
>>>>> ---
>>>>> Cc: Brett Rudley <[email protected]>
>>>>> Cc: Arend van Spriel <[email protected]>
>>>>> Cc: "Franky (Zhenhui) Lin" <[email protected]>
>>>>> Cc: Hante Meuleman <[email protected]>
>>>>> Cc: Kalle Valo <[email protected]>
>>>>> Cc: Pieter-Paul Giesberts <[email protected]>
>>>>> Cc: Daniel Kim <[email protected]>
>>>>> Cc: [email protected]
>>>>> Cc: [email protected]
>>>>> Cc: Peter Zijlstra <[email protected]>
>>>>> Cc: Ingo Molnar <[email protected]>
>>>>> Cc: [email protected]
>>>>> Cc: [email protected]
>>>>> Cc: [email protected]
>>>>> Signed-off-by: Vineet Gupta <[email protected]>
>>>>>
>>>>> Signed-off-by: Vineet Gupta <[email protected]>
>>> What's the plan with this patch? Should I take it to my
>>> wireless-drivers-next tree or will someone else take it?
>>
>>
>> Per last discussion on this topic, Arend wanted to discuss abt this with Hante.
>> I'm not taking it anyways so feel free to pick it up if you want !
>
> Well, that was before your "timeline" clarification about the generic
> function. One what tree is this patch based?

Yeah, if this patch depends on another patch I need to know about it.
Otherwise I might break something when I apply this patch.

--
Kalle Valo

2015-07-27 10:24:04

by Vineet Gupta

[permalink] [raw]
Subject: Re: [PATCH 2/3] brcmfmac: dhd_sdio.c: use existing atomic_or primitive

On Monday 27 July 2015 01:08 PM, Kalle Valo wrote:
>>> >> Per last discussion on this topic, Arend wanted to discuss abt this with Hante.
>>> >> I'm not taking it anyways so feel free to pick it up if you want !
>> >
>> > Well, that was before your "timeline" clarification about the generic
>> > function. One what tree is this patch based?
> Yeah, if this patch depends on another patch I need to know about it.
> Otherwise I might break something when I apply this patch.

It was latest linux-next at the time, 4.1-rcx perhaps, don't remember exactly. But
it certainly doesn't depend on any new code - the patch simply makes use of an
existing API vs. using a local hard coded version of same.

Give it a spin off your existing tree - shdn't be too difficult to test I presume.

-Vineet

2015-08-13 12:30:35

by Kalle Valo

[permalink] [raw]
Subject: Re: [2/3] brcmfmac: dhd_sdio.c: use existing atomic_or primitive


> There's already a generic implementation so use that instead.

Thanks, applied to wireless-drivers-next.git.

Kalle Valo