Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1261324

Re: [PATCH 2/5] do_div(): generic optimization for constant divisor on 32-bit machines

Show all headers | View raw

On Tuesday 03 November 2015 13:32:17 kbuild test robot wrote:
> 
>    net/can/bcm.c: In function 'bcm_proc_show':
> >> net/can/bcm.c:223:1: warning: the frame size of 1156 bytes is larger than 1024 bytes [-Wframe-larger-than=]
>     }

Interesting, that is a lot of stack for a function that only has a couple
of local variables:

#define IFNAMSIZ        16
        char ifname[IFNAMSIZ];
        struct sock *sk = (struct sock *)m->private;
        struct bcm_sock *bo = bcm_sk(sk);
        struct bcm_op *op;


This is a parisc-allyesconfig kernel, so I assume that CONFIG_PROFILE_ALL_BRANCHES
is on, which instruments every 'if' in the kernel. If that causes problems,
we could decide to disable the do_div optimization whenever CONFIG_PROFILE_ALL_BRANCHES
is enabled.

	Arnd
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Back to linux.kernel | Previous | Next — Next in thread | Find similar | Unroll thread

Thread

Re: [PATCH 2/5] do_div(): generic optimization for constant divisor on 32-bit machines Arnd Bergmann <arnd@arndb.de> - 2015-11-03 10:20 +0100
  Re: [PATCH 2/5] do_div(): generic optimization for constant divisor  on 32-bit machines Nicolas Pitre <nicolas.pitre@linaro.org> - 2015-11-04 22:10 +0100
    Re: [PATCH 2/5] do_div(): generic optimization for constant divisor on 32-bit machines Måns Rullgård <mans@mansr.com> - 2015-11-04 22:50 +0100

csiph-web