> From: Mitchell Blank Jr
> Cc:
> [email protected];[email protected];[email protected];
> [email protected];[email protected]
>
> > (I trimmed the cc: list a bit; no need for this to be on LKML in my opinion)
> >
> > Kris Katterjohn wrote:
> > > Forgive me because this is one of my first attempts at anything related to the
> > > kernel, but...
> > >
> > > 1) How would I go about benchmarking this?
> >
> > The first thing to do is run "size net/core/filter.o" before and after and
> > see if your change makes the "text" section larger.
> >
> > The risk of putting more stuff into the inlined function is just that
> > the rarely-executed path will end up duplicated in a bunch of places, bloating
> > the generated code. It's hard to directly benchmark the effects of this but
> > it will generally make the fast-path code less compact in the L1 I-cache
> > which (if you do it enough) slows everything down. Thats one reason why
> > kernel developers try to keep a close eye on bloat.
> >
> > -Mitch
>
> Before patch:
>
> text data bss dec hex filename
> 2399 0 0 2399 95f x/net/core/filter.o
>
> After patch:
>
> text data bss dec hex filename
> 2589 0 0 2589 a1d y/net/core/filter.o
>
> After patch without inlining the function:
>
> text data bss dec hex filename
> 2127 0 0 2127 84f y/net/core/filter.o
>
>
> So I guess use my patch and take "inline" off? What do you think?
>
>
> Thanks
>
Here's the new patch. It's the same as the first one, just with "inline" removed.
Maybe "static" should be removed, too? Oh well.
---
--- x/net/core/filter.c 2005-10-27 19:02:08.000000000 -0500
+++ y/net/core/filter.c 2005-11-03 00:05:42.000000000 -0600
@@ -13,6 +13,8 @@
* 2 of the License, or (at your option) any later version.
*
* Andi Kleen - Fix a few bad bugs and races.
+ * Kris Katterjohn - Merged __load_pointer() into load_pointer() and
+ * cleaned it up a little bit - 2005-11-01
*/
#include <linux/module.h>
@@ -35,31 +37,27 @@
#include <asm/uaccess.h>
#include <linux/filter.h>
-/* No hurry in this branch */
-static void *__load_pointer(struct sk_buff *skb, int k)
+static void *load_pointer(struct sk_buff *skb, int offset,
+ unsigned int size, void *buffer)
{
u8 *ptr = NULL;
- if (k >= SKF_NET_OFF)
- ptr = skb->nh.raw + k - SKF_NET_OFF;
- else if (k >= SKF_LL_OFF)
- ptr = skb->mac.raw + k - SKF_LL_OFF;
+ if (offset >= 0)
+ return skb_header_pointer(skb, offset, size, buffer);
+
+ if (offset >= SKF_AD_OFF)
+ return NULL;
+
+ if (offset >= SKF_NET_OFF)
+ ptr = skb->nh.raw + offset - SKF_NET_OFF;
+
+ else if (offset >= SKF_LL_OFF)
+ ptr = skb->mac.raw + offset - SKF_LL_OFF;
if (ptr >= skb->head && ptr < skb->tail)
return ptr;
- return NULL;
-}
-static inline void *load_pointer(struct sk_buff *skb, int k,
- unsigned int size, void *buffer)
-{
- if (k >= 0)
- return skb_header_pointer(skb, k, size, buffer);
- else {
- if (k >= SKF_AD_OFF)
- return NULL;
- return __load_pointer(skb, k);
- }
+ return NULL;
}
/**
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
