On Thu, 15 Aug 2002 17:31:36 -0400
Benjamin LaHaise <bcrl@redhat.com> wrote:
> Heyo,
>
> The patch below (which depends on the copy_from_user_kmalloc addition)
> reduces the stack usage in nfsctl.c, which was allocating structures that
> were 2KB or more on the stack.
>
> -ben
>
> :r ~/patches/v2.5/v2.5.31-stack-nfs.diff
> diff -urN foo-v2.5.31/fs/nfsd/nfsctl.c bar-v2.5.31/fs/nfsd/nfsctl.c
> --- foo-v2.5.31/fs/nfsd/nfsctl.c Tue Jul 30 10:24:17 2002
> +++ bar-v2.5.31/fs/nfsd/nfsctl.c Thu Aug 15 17:26:09 2002
> @@ -155,56 +155,47 @@
> * payload - write methods
> */
>
> +/* Rather than duplicate this many times, just use a funky macro. */
> +#define WRITE_METHOD(type, fn) \
> + type *data; \
> + ssize_t ret; \
> + if (size < sizeof(*data)) \
> + return -EINVAL; \
> + data = copy_from_user_kmalloc(buf, size);\
> + if (IS_ERR(data)) \
> + return PTR_ERR(data); \
> + ret = fn; \
> + kfree(data); \
> + return ret;
> +
One tiny request: make the macro an expression statement, and then use it
as "return WRITE_METHOD(xxx, yyy)".
Or even an inline function taking void * and a size.
Let's not encourage people to do returns in macros 8)
Thanks!
Rusty.
-- there are those who do and those who hang on and you don't see too many doers quoting their contemporaries. -- Larry McVoy - 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/
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