DPDK libs as one big shared object

[Thomas Monjalon]

18/06/2025 09:39, Morten Brørup:
> > Why are we still building one .so file per DPDK library, instead of just
> > building one big dpdk.so for all DPDK libraries?
> > I think it's legacy from when DPDK libraries were versioned individually, and
> > thus not relevant anymore.

I think it helps with selective packaging.


> > Wouldn't building one big dpdk.so eliminate the problems with circular
> > dependencies between DPDK libraries?
> 
> Obviously, the source code should remain organized as individual directories per library.
> I'm only suggesting linking them all into one object, so any DPDK lib can call any function in any other DPDK lib.
> 
> Perhaps only the core libs or always_enable libs should be linked into one object.
> 
> Here's an example benefit:
> I'm currently trying to convince the PMU lib author to make PMU depend on EAL [1], so missing error handling of sysconf(_SC_PAGESIZE) can be in the EAL for all uses, instead of copy-pasting sysconf(_SC_PAGESIZE) error handling to everywhere it is used.
> But this is difficult with the dependency chain for the patch adding PMU to Trace: Trace depends on PMU, and EAL depends on Trace, therefore EAL depends on PMU.
> 
> [1]: https://inbox.dpdk.org/dev/98CBD80474FA8B44BF855DF32C47DC35E9FD08@smartserver.smartshare.dk/

I don't see a problem to copy-paste in the few libs not depending on EAL.

The real solution for EAL dependencies is to split it more.
The malloc, init & logic part should be in separate libraries,
depending on the real low-level EAL.

Then all libs could depend on the low-level EAL,
and avoid copy-pasting.