* [PATCH 0/2] arch: enable GENERIC_FIND_FIRST_BIT for MIPS and ARM64
@ 2021-02-25 13:56 Yury Norov
2021-02-25 13:56 ` [RESEND PATCH 1/2] ARM64: enable GENERIC_FIND_FIRST_BIT Yury Norov
` (2 more replies)
0 siblings, 3 replies; 10+ messages in thread
From: Yury Norov @ 2021-02-25 13:56 UTC (permalink / raw)
To: Will Deacon, Catalin Marinas, Thomas Bogendoerfer,
Alexander Lobakin, Alexey Klimov, linux-arm-kernel, linux-kernel,
linux-arch, linux-mips
Cc: Yury Norov
MIPS and ARM64 don't implement find_first_{zero}_bit in arch code and
don't enable it in config. It leads to using find_next_bit() which is
less efficient:
It's beneficial to enable GENERIC_FIND_FIRST_BIT as this functionality
is not new at all and well-tested. It provides more optimized code and
saves .text memory:
Alexander Lobakin (1):
MIPS: enable GENERIC_FIND_FIRST_BIT
Yury Norov (1):
arm64: enable GENERIC_FIND_FIRST_BIT
arch/arm64/Kconfig | 1 +
arch/mips/Kconfig | 1 +
2 files changed, 2 insertions(+)
--
2.25.1
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^ permalink raw reply [flat|nested] 10+ messages in thread
* [RESEND PATCH 1/2] ARM64: enable GENERIC_FIND_FIRST_BIT
2021-02-25 13:56 [PATCH 0/2] arch: enable GENERIC_FIND_FIRST_BIT for MIPS and ARM64 Yury Norov
@ 2021-02-25 13:56 ` Yury Norov
2021-02-25 14:02 ` Will Deacon
2021-02-25 13:57 ` [PATCH 2/2] MIPS: " Yury Norov
2021-03-15 19:14 ` (subset) [PATCH 0/2] arch: enable GENERIC_FIND_FIRST_BIT for MIPS and ARM64 Catalin Marinas
2 siblings, 1 reply; 10+ messages in thread
From: Yury Norov @ 2021-02-25 13:56 UTC (permalink / raw)
To: Will Deacon, Catalin Marinas, Thomas Bogendoerfer,
Alexander Lobakin, Alexey Klimov, linux-arm-kernel, linux-kernel,
linux-arch, linux-mips
Cc: Yury Norov
ARM64 doesn't implement find_first_{zero}_bit in arch code and doesn't
enable it in a config. It leads to using find_next_bit() which is less
efficient:
0000000000000000 <find_first_bit>:
0: aa0003e4 mov x4, x0
4: aa0103e0 mov x0, x1
8: b4000181 cbz x1, 38 <find_first_bit+0x38>
c: f9400083 ldr x3, [x4]
10: d2800802 mov x2, #0x40 // #64
14: 91002084 add x4, x4, #0x8
18: b40000c3 cbz x3, 30 <find_first_bit+0x30>
1c: 14000008 b 3c <find_first_bit+0x3c>
20: f8408483 ldr x3, [x4], #8
24: 91010045 add x5, x2, #0x40
28: b50000c3 cbnz x3, 40 <find_first_bit+0x40>
2c: aa0503e2 mov x2, x5
30: eb02001f cmp x0, x2
34: 54ffff68 b.hi 20 <find_first_bit+0x20> // b.pmore
38: d65f03c0 ret
3c: d2800002 mov x2, #0x0 // #0
40: dac00063 rbit x3, x3
44: dac01063 clz x3, x3
48: 8b020062 add x2, x3, x2
4c: eb02001f cmp x0, x2
50: 9a829000 csel x0, x0, x2, ls // ls = plast
54: d65f03c0 ret
...
0000000000000118 <_find_next_bit.constprop.1>:
118: eb02007f cmp x3, x2
11c: 540002e2 b.cs 178 <_find_next_bit.constprop.1+0x60> // b.hs, b.nlast
120: d346fc66 lsr x6, x3, #6
124: f8667805 ldr x5, [x0, x6, lsl #3]
128: b4000061 cbz x1, 134 <_find_next_bit.constprop.1+0x1c>
12c: f8667826 ldr x6, [x1, x6, lsl #3]
130: 8a0600a5 and x5, x5, x6
134: ca0400a6 eor x6, x5, x4
138: 92800005 mov x5, #0xffffffffffffffff // #-1
13c: 9ac320a5 lsl x5, x5, x3
140: 927ae463 and x3, x3, #0xffffffffffffffc0
144: ea0600a5 ands x5, x5, x6
148: 54000120 b.eq 16c <_find_next_bit.constprop.1+0x54> // b.none
14c: 1400000e b 184 <_find_next_bit.constprop.1+0x6c>
150: d346fc66 lsr x6, x3, #6
154: f8667805 ldr x5, [x0, x6, lsl #3]
158: b4000061 cbz x1, 164 <_find_next_bit.constprop.1+0x4c>
15c: f8667826 ldr x6, [x1, x6, lsl #3]
160: 8a0600a5 and x5, x5, x6
164: eb05009f cmp x4, x5
168: 540000c1 b.ne 180 <_find_next_bit.constprop.1+0x68> // b.any
16c: 91010063 add x3, x3, #0x40
170: eb03005f cmp x2, x3
174: 54fffee8 b.hi 150 <_find_next_bit.constprop.1+0x38> // b.pmore
178: aa0203e0 mov x0, x2
17c: d65f03c0 ret
180: ca050085 eor x5, x4, x5
184: dac000a5 rbit x5, x5
188: dac010a5 clz x5, x5
18c: 8b0300a3 add x3, x5, x3
190: eb03005f cmp x2, x3
194: 9a839042 csel x2, x2, x3, ls // ls = plast
198: aa0203e0 mov x0, x2
19c: d65f03c0 ret
...
0000000000000238 <find_next_bit>:
238: a9bf7bfd stp x29, x30, [sp, #-16]!
23c: aa0203e3 mov x3, x2
240: d2800004 mov x4, #0x0 // #0
244: aa0103e2 mov x2, x1
248: 910003fd mov x29, sp
24c: d2800001 mov x1, #0x0 // #0
250: 97ffffb2 bl 118 <_find_next_bit.constprop.1>
254: a8c17bfd ldp x29, x30, [sp], #16
258: d65f03c0 ret
Enabling find_{first,next}_bit() would also benefit for_each_{set,clear}_bit().
On A-53 find_first_bit() is almost twice faster than find_next_bit(), according
to lib/find_bit_benchmark (thanks to Alexey for testing):
GENERIC_FIND_FIRST_BIT=n:
[7126084.948181] find_first_bit: 47389224 ns, 16357 iterations
[7126085.032315] find_first_bit: 19048193 ns, 655 iterations
GENERIC_FIND_FIRST_BIT=y:
[ 84.158068] find_first_bit: 27193319 ns, 16406 iterations
[ 84.233005] find_first_bit: 11082437 ns, 656 iterations
GENERIC_FIND_FIRST_BIT=n bloats the kernel despite that it disables generation
of find_{first,next}_bit():
yury:linux$ scripts/bloat-o-meter vmlinux vmlinux.ffb
add/remove: 4/1 grow/shrink: 19/251 up/down: 564/-1692 (-1128)
...
Overall, GENERIC_FIND_FIRST_BIT=n is harmful both in terms of performance and
code size, and it's better to have GENERIC_FIND_FIRST_BIT enabled.
Tested-by: Alexey Klimov <aklimov@redhat.com>
Signed-off-by: Yury Norov <yury.norov@gmail.com>
---
arch/arm64/Kconfig | 1 +
1 file changed, 1 insertion(+)
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 31bd885b79eb..5596eab04092 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -108,6 +108,7 @@ config ARM64
select GENERIC_CPU_AUTOPROBE
select GENERIC_CPU_VULNERABILITIES
select GENERIC_EARLY_IOREMAP
+ select GENERIC_FIND_FIRST_BIT
select GENERIC_IDLE_POLL_SETUP
select GENERIC_IRQ_IPI
select GENERIC_IRQ_MULTI_HANDLER
--
2.25.1
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^ permalink raw reply related [flat|nested] 10+ messages in thread
* [PATCH 2/2] MIPS: enable GENERIC_FIND_FIRST_BIT
2021-02-25 13:56 [PATCH 0/2] arch: enable GENERIC_FIND_FIRST_BIT for MIPS and ARM64 Yury Norov
2021-02-25 13:56 ` [RESEND PATCH 1/2] ARM64: enable GENERIC_FIND_FIRST_BIT Yury Norov
@ 2021-02-25 13:57 ` Yury Norov
2021-02-26 1:22 ` Huacai Chen
2021-03-01 14:49 ` Thomas Bogendoerfer
2021-03-15 19:14 ` (subset) [PATCH 0/2] arch: enable GENERIC_FIND_FIRST_BIT for MIPS and ARM64 Catalin Marinas
2 siblings, 2 replies; 10+ messages in thread
From: Yury Norov @ 2021-02-25 13:57 UTC (permalink / raw)
To: Will Deacon, Catalin Marinas, Thomas Bogendoerfer,
Alexander Lobakin, Alexey Klimov, linux-arm-kernel, linux-kernel,
linux-arch, linux-mips
Cc: Yury Norov
From: Alexander Lobakin <alobakin@pm.me>
MIPS doesn't have architecture-optimized bitsearching functions,
like find_{first,next}_bit() etc.
It's absolutely harmless to enable GENERIC_FIND_FIRST_BIT as this
functionality is not new at all and well-tested. It provides more
optimized code and saves some .text memory (32 R2):
add/remove: 4/1 grow/shrink: 1/53 up/down: 216/-372 (-156)
Users of for_each_set_bit() like hotpath gic_handle_shared_int()
will also benefit from this.
Suggested-by: Yury Norov <yury.norov@gmail.com>
Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Signed-off-by: Yury Norov <yury.norov@gmail.com>
---
arch/mips/Kconfig | 1 +
1 file changed, 1 insertion(+)
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index d89efba3d8a4..164bdd715d4b 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -26,6 +26,7 @@ config MIPS
select GENERIC_ATOMIC64 if !64BIT
select GENERIC_CMOS_UPDATE
select GENERIC_CPU_AUTOPROBE
+ select GENERIC_FIND_FIRST_BIT
select GENERIC_GETTIMEOFDAY
select GENERIC_IOMAP
select GENERIC_IRQ_PROBE
--
2.25.1
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^ permalink raw reply related [flat|nested] 10+ messages in thread
* Re: [RESEND PATCH 1/2] ARM64: enable GENERIC_FIND_FIRST_BIT
2021-02-25 13:56 ` [RESEND PATCH 1/2] ARM64: enable GENERIC_FIND_FIRST_BIT Yury Norov
@ 2021-02-25 14:02 ` Will Deacon
2021-03-03 22:17 ` Yury Norov
0 siblings, 1 reply; 10+ messages in thread
From: Will Deacon @ 2021-02-25 14:02 UTC (permalink / raw)
To: Yury Norov
Cc: linux-arch, Thomas Bogendoerfer, Alexander Lobakin,
Catalin Marinas, linux-kernel, linux-mips, Alexey Klimov,
linux-arm-kernel
On Thu, Feb 25, 2021 at 05:56:59AM -0800, Yury Norov wrote:
> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> index 31bd885b79eb..5596eab04092 100644
> --- a/arch/arm64/Kconfig
> +++ b/arch/arm64/Kconfig
> @@ -108,6 +108,7 @@ config ARM64
> select GENERIC_CPU_AUTOPROBE
> select GENERIC_CPU_VULNERABILITIES
> select GENERIC_EARLY_IOREMAP
> + select GENERIC_FIND_FIRST_BIT
> select GENERIC_IDLE_POLL_SETUP
> select GENERIC_IRQ_IPI
> select GENERIC_IRQ_MULTI_HANDLER
Acked-by: Will Deacon <will@kernel.org>
Catalin can pick this up later in the cycle.
Will
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^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH 2/2] MIPS: enable GENERIC_FIND_FIRST_BIT
2021-02-25 13:57 ` [PATCH 2/2] MIPS: " Yury Norov
@ 2021-02-26 1:22 ` Huacai Chen
2021-02-26 4:07 ` Yury Norov
2021-03-01 14:49 ` Thomas Bogendoerfer
1 sibling, 1 reply; 10+ messages in thread
From: Huacai Chen @ 2021-02-26 1:22 UTC (permalink / raw)
To: Yury Norov
Cc: linux-arch, Thomas Bogendoerfer, Alexander Lobakin,
Catalin Marinas, LKML, open list:MIPS, Alexey Klimov,
Will Deacon, linux-arm-kernel
Hi, Yury,
On Thu, Feb 25, 2021 at 9:59 PM Yury Norov <yury.norov@gmail.com> wrote:
>
> From: Alexander Lobakin <alobakin@pm.me>
>
> MIPS doesn't have architecture-optimized bitsearching functions,
> like find_{first,next}_bit() etc.
Emm, I think MIPS can use clo/clz to optimize bitsearching functions.
Huacai
> It's absolutely harmless to enable GENERIC_FIND_FIRST_BIT as this
> functionality is not new at all and well-tested. It provides more
> optimized code and saves some .text memory (32 R2):
>
> add/remove: 4/1 grow/shrink: 1/53 up/down: 216/-372 (-156)
>
> Users of for_each_set_bit() like hotpath gic_handle_shared_int()
> will also benefit from this.
>
> Suggested-by: Yury Norov <yury.norov@gmail.com>
> Signed-off-by: Alexander Lobakin <alobakin@pm.me>
> Signed-off-by: Yury Norov <yury.norov@gmail.com>
> ---
> arch/mips/Kconfig | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
> index d89efba3d8a4..164bdd715d4b 100644
> --- a/arch/mips/Kconfig
> +++ b/arch/mips/Kconfig
> @@ -26,6 +26,7 @@ config MIPS
> select GENERIC_ATOMIC64 if !64BIT
> select GENERIC_CMOS_UPDATE
> select GENERIC_CPU_AUTOPROBE
> + select GENERIC_FIND_FIRST_BIT
> select GENERIC_GETTIMEOFDAY
> select GENERIC_IOMAP
> select GENERIC_IRQ_PROBE
> --
> 2.25.1
>
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^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH 2/2] MIPS: enable GENERIC_FIND_FIRST_BIT
2021-02-26 1:22 ` Huacai Chen
@ 2021-02-26 4:07 ` Yury Norov
0 siblings, 0 replies; 10+ messages in thread
From: Yury Norov @ 2021-02-26 4:07 UTC (permalink / raw)
To: Huacai Chen
Cc: linux-arch, Thomas Bogendoerfer, Alexander Lobakin,
Catalin Marinas, LKML, open list:MIPS, Alexey Klimov,
Will Deacon, linux-arm-kernel
On Fri, Feb 26, 2021 at 09:22:18AM +0800, Huacai Chen wrote:
> Hi, Yury,
>
> On Thu, Feb 25, 2021 at 9:59 PM Yury Norov <yury.norov@gmail.com> wrote:
> >
> > From: Alexander Lobakin <alobakin@pm.me>
> >
> > MIPS doesn't have architecture-optimized bitsearching functions,
> > like find_{first,next}_bit() etc.
> Emm, I think MIPS can use clo/clz to optimize bitsearching functions.
find_{first,next}_bit() is about manipulating the bitmaps bigger that
a single word, and some arches (arm) implement their own find_bit()
functions. find_bit() is not a replacement of __ffs() and ffz().
> Huacai
>
> > It's absolutely harmless to enable GENERIC_FIND_FIRST_BIT as this
> > functionality is not new at all and well-tested. It provides more
> > optimized code and saves some .text memory (32 R2):
> >
> > add/remove: 4/1 grow/shrink: 1/53 up/down: 216/-372 (-156)
> >
> > Users of for_each_set_bit() like hotpath gic_handle_shared_int()
> > will also benefit from this.
> >
> > Suggested-by: Yury Norov <yury.norov@gmail.com>
> > Signed-off-by: Alexander Lobakin <alobakin@pm.me>
> > Signed-off-by: Yury Norov <yury.norov@gmail.com>
> > ---
> > arch/mips/Kconfig | 1 +
> > 1 file changed, 1 insertion(+)
> >
> > diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
> > index d89efba3d8a4..164bdd715d4b 100644
> > --- a/arch/mips/Kconfig
> > +++ b/arch/mips/Kconfig
> > @@ -26,6 +26,7 @@ config MIPS
> > select GENERIC_ATOMIC64 if !64BIT
> > select GENERIC_CMOS_UPDATE
> > select GENERIC_CPU_AUTOPROBE
> > + select GENERIC_FIND_FIRST_BIT
> > select GENERIC_GETTIMEOFDAY
> > select GENERIC_IOMAP
> > select GENERIC_IRQ_PROBE
> > --
> > 2.25.1
> >
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http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH 2/2] MIPS: enable GENERIC_FIND_FIRST_BIT
2021-02-25 13:57 ` [PATCH 2/2] MIPS: " Yury Norov
2021-02-26 1:22 ` Huacai Chen
@ 2021-03-01 14:49 ` Thomas Bogendoerfer
1 sibling, 0 replies; 10+ messages in thread
From: Thomas Bogendoerfer @ 2021-03-01 14:49 UTC (permalink / raw)
To: Yury Norov
Cc: linux-arch, Alexander Lobakin, Catalin Marinas, linux-kernel,
linux-mips, Alexey Klimov, Will Deacon, linux-arm-kernel
On Thu, Feb 25, 2021 at 05:57:00AM -0800, Yury Norov wrote:
> From: Alexander Lobakin <alobakin@pm.me>
>
> MIPS doesn't have architecture-optimized bitsearching functions,
> like find_{first,next}_bit() etc.
> It's absolutely harmless to enable GENERIC_FIND_FIRST_BIT as this
> functionality is not new at all and well-tested. It provides more
> optimized code and saves some .text memory (32 R2):
>
> add/remove: 4/1 grow/shrink: 1/53 up/down: 216/-372 (-156)
>
> Users of for_each_set_bit() like hotpath gic_handle_shared_int()
> will also benefit from this.
>
> Suggested-by: Yury Norov <yury.norov@gmail.com>
> Signed-off-by: Alexander Lobakin <alobakin@pm.me>
> Signed-off-by: Yury Norov <yury.norov@gmail.com>
> ---
> arch/mips/Kconfig | 1 +
> 1 file changed, 1 insertion(+)
applied to mips-next.
Thomas.
--
Crap can work. Given enough thrust pigs will fly, but it's not necessarily a
good idea. [ RFC1925, 2.3 ]
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^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [RESEND PATCH 1/2] ARM64: enable GENERIC_FIND_FIRST_BIT
2021-02-25 14:02 ` Will Deacon
@ 2021-03-03 22:17 ` Yury Norov
2021-03-05 11:20 ` Catalin Marinas
0 siblings, 1 reply; 10+ messages in thread
From: Yury Norov @ 2021-03-03 22:17 UTC (permalink / raw)
To: Will Deacon
Cc: Catalin Marinas, Thomas Bogendoerfer, Alexander Lobakin,
Alexey Klimov, linux-arm-kernel, linux-kernel, linux-arch,
linux-mips
On Thu, Feb 25, 2021 at 02:02:06PM +0000, Will Deacon wrote:
> On Thu, Feb 25, 2021 at 05:56:59AM -0800, Yury Norov wrote:
> > diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> > index 31bd885b79eb..5596eab04092 100644
> > --- a/arch/arm64/Kconfig
> > +++ b/arch/arm64/Kconfig
> > @@ -108,6 +108,7 @@ config ARM64
> > select GENERIC_CPU_AUTOPROBE
> > select GENERIC_CPU_VULNERABILITIES
> > select GENERIC_EARLY_IOREMAP
> > + select GENERIC_FIND_FIRST_BIT
> > select GENERIC_IDLE_POLL_SETUP
> > select GENERIC_IRQ_IPI
> > select GENERIC_IRQ_MULTI_HANDLER
>
> Acked-by: Will Deacon <will@kernel.org>
>
> Catalin can pick this up later in the cycle.
>
> Will
Ping?
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^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [RESEND PATCH 1/2] ARM64: enable GENERIC_FIND_FIRST_BIT
2021-03-03 22:17 ` Yury Norov
@ 2021-03-05 11:20 ` Catalin Marinas
0 siblings, 0 replies; 10+ messages in thread
From: Catalin Marinas @ 2021-03-05 11:20 UTC (permalink / raw)
To: Yury Norov
Cc: Will Deacon, Thomas Bogendoerfer, Alexander Lobakin,
Alexey Klimov, linux-arm-kernel, linux-kernel, linux-arch,
linux-mips
On Wed, Mar 03, 2021 at 02:17:41PM -0800, Yury Norov wrote:
> On Thu, Feb 25, 2021 at 02:02:06PM +0000, Will Deacon wrote:
> > On Thu, Feb 25, 2021 at 05:56:59AM -0800, Yury Norov wrote:
> > > diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> > > index 31bd885b79eb..5596eab04092 100644
> > > --- a/arch/arm64/Kconfig
> > > +++ b/arch/arm64/Kconfig
> > > @@ -108,6 +108,7 @@ config ARM64
> > > select GENERIC_CPU_AUTOPROBE
> > > select GENERIC_CPU_VULNERABILITIES
> > > select GENERIC_EARLY_IOREMAP
> > > + select GENERIC_FIND_FIRST_BIT
> > > select GENERIC_IDLE_POLL_SETUP
> > > select GENERIC_IRQ_IPI
> > > select GENERIC_IRQ_MULTI_HANDLER
> >
> > Acked-by: Will Deacon <will@kernel.org>
> >
> > Catalin can pick this up later in the cycle.
> >
> > Will
>
> Ping?
It's on my list for 5.13 but I'll only start queuing patches after -rc3.
--
Catalin
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^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: (subset) [PATCH 0/2] arch: enable GENERIC_FIND_FIRST_BIT for MIPS and ARM64
2021-02-25 13:56 [PATCH 0/2] arch: enable GENERIC_FIND_FIRST_BIT for MIPS and ARM64 Yury Norov
2021-02-25 13:56 ` [RESEND PATCH 1/2] ARM64: enable GENERIC_FIND_FIRST_BIT Yury Norov
2021-02-25 13:57 ` [PATCH 2/2] MIPS: " Yury Norov
@ 2021-03-15 19:14 ` Catalin Marinas
2 siblings, 0 replies; 10+ messages in thread
From: Catalin Marinas @ 2021-03-15 19:14 UTC (permalink / raw)
To: linux-mips, linux-kernel, Yury Norov, linux-arm-kernel,
Alexey Klimov, linux-arch, Will Deacon, Alexander Lobakin,
Thomas Bogendoerfer
On Thu, 25 Feb 2021 05:56:58 -0800, Yury Norov wrote:
> MIPS and ARM64 don't implement find_first_{zero}_bit in arch code and
> don't enable it in config. It leads to using find_next_bit() which is
> less efficient:
>
> It's beneficial to enable GENERIC_FIND_FIRST_BIT as this functionality
> is not new at all and well-tested. It provides more optimized code and
> saves .text memory:
>
> [...]
Applied to arm64 (for-next/misc), thanks!
[1/2] ARM64: enable GENERIC_FIND_FIRST_BIT
https://git.kernel.org/arm64/c/98c5ec77c7c5
--
Catalin
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^ permalink raw reply [flat|nested] 10+ messages in thread
end of thread, other threads:[~2021-03-15 19:15 UTC | newest]
Thread overview: 10+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-02-25 13:56 [PATCH 0/2] arch: enable GENERIC_FIND_FIRST_BIT for MIPS and ARM64 Yury Norov
2021-02-25 13:56 ` [RESEND PATCH 1/2] ARM64: enable GENERIC_FIND_FIRST_BIT Yury Norov
2021-02-25 14:02 ` Will Deacon
2021-03-03 22:17 ` Yury Norov
2021-03-05 11:20 ` Catalin Marinas
2021-02-25 13:57 ` [PATCH 2/2] MIPS: " Yury Norov
2021-02-26 1:22 ` Huacai Chen
2021-02-26 4:07 ` Yury Norov
2021-03-01 14:49 ` Thomas Bogendoerfer
2021-03-15 19:14 ` (subset) [PATCH 0/2] arch: enable GENERIC_FIND_FIRST_BIT for MIPS and ARM64 Catalin Marinas
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