Re: [PATCH v2] net/i40e: remove weak symbols

Hi,

I forgot to add the i40 maintainers as well. Would anyone like to weigh in?

Regards,

Zoltan

On 22/07/16 12:34, Zoltan Kiss wrote:

On 21/07/16 19:58, bynes adam wrote:

quoted

On Wed, Jul 20, 2016 at 06:11:16PM +0100, Zoltan Kiss wrote:
Hi, Kiss

quoted

Using weak symbols have a few issues with static linking:

- normally the linker searches the .o files already linked, if your weak
  one is there, it won't check if there is a strong version
- unless the symbol is directly referred, but it's not the right
thing to
  rely on
- or --whole-archive specified in the command line, which pulls in a lot
  of unwanted stuff

--whole-archive on the other hand can ensure all the object files are
linked,
and the strong symbol will take precedence over weak symbol. So we
don't need to
take care of the sequence of the object files in the ar or between ar.

--whole-archive is primarily for shared libraries, just as weak symbols.
When people do static linking, their reason is often to avoid carrying
around a big library while they only use a fraction of it.

quoted

quoted

- whole-archive also makes libtool dropping the library from the command
  line, which is what should happen with dynamic linking, but not with
  static (observed on Ubuntu 14.04). This is an important bug if you
  build a static library depending on DPDK

you mean the libtool bug for --whole-archive?
if it does, you shouldn't using the libtool,

GNU libtool is a quite common tool for building libraries, it's a bit
painful sometimes, but it works. What else do you recommend? I mean,
something which is proven to be better?

quoted

BTW what's the circumstance you must use the libtool. using you own
makefile for
the library or APP.

Building libraries which depend on DPDK

quoted

quoted

This patch merges the two version and make the behaviour rely on the
config.

If we can agree in the concept, I can send a series to fix this for the
other weak functions.

Signed-off-by: Zoltan Kiss <redacted>
---

Notes:
    v2: fix commit message

 drivers/net/i40e/i40e_rxtx.c     | 36
+++++++++++++++++++++++++++++++++++-
 drivers/net/i40e/i40e_rxtx_vec.c | 36
------------------------------------
 2 files changed, 35 insertions(+), 37 deletions(-)

From the original design, we follow the rule, we don't want the Macro
in the file
to seperate the different Rx/Tx path for disabled/enabled vector
configuration.

And why is it better to compile two versions of the same function when
you already know at the time of compilation which one do you want to use?

quoted

Adam Bynes