All of lore.kernel.org
 help / color / mirror / Atom feed
From: will.deacon@arm.com (Will Deacon)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH] ARM64: Fix compiling with GCC 6 and Atomics enabled
Date: Mon, 21 Dec 2015 12:38:43 +0000	[thread overview]
Message-ID: <20151221123843.GM23092@arm.com> (raw)
In-Reply-To: <1450498655-3820-1-git-send-email-apinski@cavium.com>

On Fri, Dec 18, 2015 at 08:17:35PM -0800, Andrew Pinski wrote:
> The problem here is that GCC 6 and above emits .arch now
> for each function so now the global .arch_extension has
> no effect.  This fixes the problem by putting
> .arch_extension inside ARM64_LSE_ATOMIC_INSN so
> it is enabled for each place where LSE is used.

Hmm, this is going to affect arch/arm/ much more heavily than arch/arm64.
.arch_extension is used for virt, mp and sec over there, and it may be
tricky to isolate the actual instruction usage (at least, virt looks
lost in kvm/arm.c).

Why can't gas have an option to accept all instruction encodings that it
knows about, inspite of any .arch directives?

Will

> Signed-off-by: Andrew Pinski <apinski@cavium.com>
> ---
>  arch/arm64/include/asm/lse.h |    4 +---
>  1 files changed, 1 insertions(+), 3 deletions(-)
> 
> diff --git a/arch/arm64/include/asm/lse.h b/arch/arm64/include/asm/lse.h
> index 3de42d6..625601f 100644
> --- a/arch/arm64/include/asm/lse.h
> +++ b/arch/arm64/include/asm/lse.h
> @@ -17,8 +17,6 @@
>  
>  #else	/* __ASSEMBLER__ */
>  
> -__asm__(".arch_extension	lse");
> -
>  /* Move the ll/sc atomics out-of-line */
>  #define __LL_SC_INLINE
>  #define __LL_SC_PREFIX(x)	__ll_sc_##x
> @@ -29,7 +27,7 @@ __asm__(".arch_extension	lse");
>  
>  /* In-line patching at runtime */
>  #define ARM64_LSE_ATOMIC_INSN(llsc, lse)				\
> -	ALTERNATIVE(llsc, lse, ARM64_HAS_LSE_ATOMICS)
> +	ALTERNATIVE(".arch_extension        lse\n" llsc, lse, ARM64_HAS_LSE_ATOMICS)
>  
>  #endif	/* __ASSEMBLER__ */
>  #else	/* CONFIG_AS_LSE && CONFIG_ARM64_LSE_ATOMICS */
> -- 
> 1.7.2.5
> 
> 
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
> 

WARNING: multiple messages have this Message-ID (diff)
From: Will Deacon <will.deacon@arm.com>
To: Andrew Pinski <apinski@cavium.com>
Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] ARM64: Fix compiling with GCC 6 and Atomics enabled
Date: Mon, 21 Dec 2015 12:38:43 +0000	[thread overview]
Message-ID: <20151221123843.GM23092@arm.com> (raw)
In-Reply-To: <1450498655-3820-1-git-send-email-apinski@cavium.com>

On Fri, Dec 18, 2015 at 08:17:35PM -0800, Andrew Pinski wrote:
> The problem here is that GCC 6 and above emits .arch now
> for each function so now the global .arch_extension has
> no effect.  This fixes the problem by putting
> .arch_extension inside ARM64_LSE_ATOMIC_INSN so
> it is enabled for each place where LSE is used.

Hmm, this is going to affect arch/arm/ much more heavily than arch/arm64.
.arch_extension is used for virt, mp and sec over there, and it may be
tricky to isolate the actual instruction usage (at least, virt looks
lost in kvm/arm.c).

Why can't gas have an option to accept all instruction encodings that it
knows about, inspite of any .arch directives?

Will

> Signed-off-by: Andrew Pinski <apinski@cavium.com>
> ---
>  arch/arm64/include/asm/lse.h |    4 +---
>  1 files changed, 1 insertions(+), 3 deletions(-)
> 
> diff --git a/arch/arm64/include/asm/lse.h b/arch/arm64/include/asm/lse.h
> index 3de42d6..625601f 100644
> --- a/arch/arm64/include/asm/lse.h
> +++ b/arch/arm64/include/asm/lse.h
> @@ -17,8 +17,6 @@
>  
>  #else	/* __ASSEMBLER__ */
>  
> -__asm__(".arch_extension	lse");
> -
>  /* Move the ll/sc atomics out-of-line */
>  #define __LL_SC_INLINE
>  #define __LL_SC_PREFIX(x)	__ll_sc_##x
> @@ -29,7 +27,7 @@ __asm__(".arch_extension	lse");
>  
>  /* In-line patching at runtime */
>  #define ARM64_LSE_ATOMIC_INSN(llsc, lse)				\
> -	ALTERNATIVE(llsc, lse, ARM64_HAS_LSE_ATOMICS)
> +	ALTERNATIVE(".arch_extension        lse\n" llsc, lse, ARM64_HAS_LSE_ATOMICS)
>  
>  #endif	/* __ASSEMBLER__ */
>  #else	/* CONFIG_AS_LSE && CONFIG_ARM64_LSE_ATOMICS */
> -- 
> 1.7.2.5
> 
> 
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
> 

  reply	other threads:[~2015-12-21 12:38 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-12-19  4:17 [PATCH] ARM64: Fix compiling with GCC 6 and Atomics enabled Andrew Pinski
2015-12-19  4:17 ` Andrew Pinski
2015-12-21 12:38 ` Will Deacon [this message]
2015-12-21 12:38   ` Will Deacon
2015-12-21 12:46   ` Ard Biesheuvel
2015-12-21 12:46     ` Ard Biesheuvel
2015-12-21 12:51     ` Will Deacon
2015-12-21 12:51       ` Will Deacon
2015-12-21 12:58       ` Ard Biesheuvel
2015-12-21 12:58         ` Ard Biesheuvel
2015-12-21 13:37         ` Will Deacon
2015-12-21 13:37           ` Will Deacon
2016-01-21 12:32           ` Vladimir Murzin
2016-01-21 12:32             ` Vladimir Murzin
2016-01-21 14:32             ` Ard Biesheuvel
2016-01-21 14:32               ` Ard Biesheuvel
2015-12-21 13:03     ` Russell King - ARM Linux
2015-12-21 13:03       ` Russell King - ARM Linux

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20151221123843.GM23092@arm.com \
    --to=will.deacon@arm.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.