Re: [PATCH 4/5] printk: use alloc_bootmem() instead of memblock_alloc().

[Yinghai Lu <yinghai@kernel.org>]

On Mon, Mar 12, 2012 at 10:36 PM, Avery Pennarun <apenwarr@gmail.com> wrote:
> The code in setup_log_buf() had two memory allocation branches, depending
> on the value of 'early'.  If early==1, it would use memblock_alloc(); if
> early==0, it would use alloc_bootmem_nopanic().
>
> bootmem should already configured by the time setup_log_buf(early=1) is
> called, so there's no reason to have the separation.  Furthermore, on
> arches with nobootmem, memblock_alloc is essentially the same as
> alloc_bootmem anyway.  x86 is one such arch, and also the only one
> that uses early=1.
>
> Signed-off-by: Avery Pennarun <apenwarr@gmail.com>
> ---
>  kernel/printk.c |   13 +------------
>  1 files changed, 1 insertions(+), 12 deletions(-)
>
> diff --git a/kernel/printk.c b/kernel/printk.c
> index 32690a0..bf96a7d 100644
> --- a/kernel/printk.c
> +++ b/kernel/printk.c
> @@ -31,7 +31,6 @@
>  #include <linux/smp.h>
>  #include <linux/security.h>
>  #include <linux/bootmem.h>
> -#include <linux/memblock.h>
>  #include <linux/syscalls.h>
>  #include <linux/kexec.h>
>  #include <linux/kdb.h>
> @@ -195,17 +194,7 @@ void __init setup_log_buf(int early)
>        if (!new_log_buf_len)
>                return;
>
> -       if (early) {
> -               unsigned long mem;
> -
> -               mem = memblock_alloc(new_log_buf_len, PAGE_SIZE);
> -               if (!mem)
> -                       return;
> -               new_log_buf = __va(mem);
> -       } else {
> -               new_log_buf = alloc_bootmem_nopanic(new_log_buf_len);
> -       }
> -
> +       new_log_buf = alloc_bootmem_nopanic(new_log_buf_len);
>        if (unlikely(!new_log_buf)) {
>                pr_err("log_buf_len: %ld bytes not available\n",
>                        new_log_buf_len);
> --

that seems not right.

for x86, setup_log_buf(1) is quite early called in setup_arch() before
bootmem is there.

bootmem should be killed after memblock is supported for arch that
current support bootmem.

Yinghai

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>