LKML Archive on lore.kernel.org
 help / Atom feed
From: Guenter Roeck <linux@roeck-us.net>
To: Palmer Dabbelt <palmer@sifive.com>
Cc: Christoph Hellwig <hch@infradead.org>,
	aou@eecs.berkeley.edu, tklauser@distanz.ch,
	Arnd Bergmann <arnd@arndb.de>,
	Andrew Waterman <andrew@sifive.com>,
	linux@dominikbrodowski.net, dan.carpenter@oracle.com,
	linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v3 1/2] RISC-V: Define sys_riscv_flush_icache when SMP=n
Date: Fri, 10 Aug 2018 07:07:36 -0700
Message-ID: <20180810140736.GA13061@roeck-us.net> (raw)
In-Reply-To: <20180809221952.24260-2-palmer@sifive.com>

On Thu, Aug 09, 2018 at 03:19:51PM -0700, Palmer Dabbelt wrote:
> This would be necessary to make non-SMP builds work, but there is
> another error in the implementation of our syscall linkage that actually
> just causes sys_riscv_flush_icache to never build.  I've build tested
> this on allnoconfig and allnoconfig+SMP=y, as well as defconfig like
> normal.
> 
> CC: Christoph Hellwig <hch@infradead.org>
> CC: Guenter Roeck <linux@roeck-us.net>
> In-Reply-To: <20180809055830.GA17533@infradead.org>
> In-Reply-To: <20180809132612.GA31058@roeck-us.net>
> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>

Tested-by: Guenter Roeck <linux@roeck-us.net>

> ---
>  arch/riscv/include/asm/vdso.h |  2 --
>  arch/riscv/kernel/sys_riscv.c | 12 ++++++++++--
>  2 files changed, 10 insertions(+), 4 deletions(-)
> 
> diff --git a/arch/riscv/include/asm/vdso.h b/arch/riscv/include/asm/vdso.h
> index 541544d64c33..ec6180a4b55d 100644
> --- a/arch/riscv/include/asm/vdso.h
> +++ b/arch/riscv/include/asm/vdso.h
> @@ -38,8 +38,6 @@ struct vdso_data {
>  	(void __user *)((unsigned long)(base) + __vdso_##name);			\
>  })
>  
> -#ifdef CONFIG_SMP
>  asmlinkage long sys_riscv_flush_icache(uintptr_t, uintptr_t, uintptr_t);
> -#endif
>  
>  #endif /* _ASM_RISCV_VDSO_H */
> diff --git a/arch/riscv/kernel/sys_riscv.c b/arch/riscv/kernel/sys_riscv.c
> index f7181ed8aafc..568026ccf6e8 100644
> --- a/arch/riscv/kernel/sys_riscv.c
> +++ b/arch/riscv/kernel/sys_riscv.c
> @@ -48,7 +48,6 @@ SYSCALL_DEFINE6(mmap2, unsigned long, addr, unsigned long, len,
>  }
>  #endif /* !CONFIG_64BIT */
>  
> -#ifdef CONFIG_SMP
>  /*
>   * Allows the instruction cache to be flushed from userspace.  Despite RISC-V
>   * having a direct 'fence.i' instruction available to userspace (which we
> @@ -66,15 +65,24 @@ SYSCALL_DEFINE6(mmap2, unsigned long, addr, unsigned long, len,
>  SYSCALL_DEFINE3(riscv_flush_icache, uintptr_t, start, uintptr_t, end,
>  	uintptr_t, flags)
>  {
> +#ifdef CONFIG_SMP
>  	struct mm_struct *mm = current->mm;
>  	bool local = (flags & SYS_RISCV_FLUSH_ICACHE_LOCAL) != 0;
> +#endif
>  
>  	/* Check the reserved flags. */
>  	if (unlikely(flags & ~SYS_RISCV_FLUSH_ICACHE_ALL))
>  		return -EINVAL;
>  
> +	/*
> +	 * Without CONFIG_SMP flush_icache_mm is a just a flush_icache_all(),
> +	 * which generates unused variable warnings all over this function.
> +	 */
> +#ifdef CONFIG_SMP
>  	flush_icache_mm(mm, local);
> +#else
> +	flush_icache_all();
> +#endif
>  
>  	return 0;
>  }
> -#endif
> -- 
> 2.16.4
> 

  parent reply index

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-08-09 22:19 RISC-V: Don't use a global include guard for uapi/asm/syscalls Palmer Dabbelt
2018-08-09 22:19 ` [PATCH v3 1/2] RISC-V: Define sys_riscv_flush_icache when SMP=n Palmer Dabbelt
2018-08-10  8:38   ` Christoph Hellwig
2018-08-10 18:27     ` Palmer Dabbelt
2018-08-10 18:47       ` Guenter Roeck
2018-08-10 20:55         ` Palmer Dabbelt
2018-08-14 13:35       ` Christoph Hellwig
2018-08-10 14:07   ` Guenter Roeck [this message]
2018-08-14 13:39   ` Christoph Hellwig
2018-08-20 23:30     ` Palmer Dabbelt
2018-08-09 22:19 ` [PATCH v3 2/2] RISC-V: Don't use a global include guard for uapi/asm/syscalls.h Palmer Dabbelt
2018-08-10 14:07   ` Guenter Roeck
2018-08-14 13:40   ` Christoph Hellwig
2018-08-20 23:30     ` Palmer Dabbelt

Reply instructions:

You may reply publically 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=20180810140736.GA13061@roeck-us.net \
    --to=linux@roeck-us.net \
    --cc=andrew@sifive.com \
    --cc=aou@eecs.berkeley.edu \
    --cc=arnd@arndb.de \
    --cc=dan.carpenter@oracle.com \
    --cc=hch@infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-riscv@lists.infradead.org \
    --cc=linux@dominikbrodowski.net \
    --cc=palmer@sifive.com \
    --cc=tklauser@distanz.ch \
    /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

LKML Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/lkml/0 lkml/git/0.git
	git clone --mirror https://lore.kernel.org/lkml/1 lkml/git/1.git
	git clone --mirror https://lore.kernel.org/lkml/2 lkml/git/2.git
	git clone --mirror https://lore.kernel.org/lkml/3 lkml/git/3.git
	git clone --mirror https://lore.kernel.org/lkml/4 lkml/git/4.git
	git clone --mirror https://lore.kernel.org/lkml/5 lkml/git/5.git
	git clone --mirror https://lore.kernel.org/lkml/6 lkml/git/6.git
	git clone --mirror https://lore.kernel.org/lkml/7 lkml/git/7.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 lkml lkml/ https://lore.kernel.org/lkml \
		linux-kernel@vger.kernel.org linux-kernel@archiver.kernel.org
	public-inbox-index lkml


Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-kernel


AGPL code for this site: git clone https://public-inbox.org/ public-inbox