On Tue, 15 Mar 2005 17:13:11 +0100
Eric Dumazet <dada1@xxxxxxxxxxxxx> wrote:
> I suggest in this patch using an array of 256 rwlocks.
> - Less memory used (or 2 x more entries in hash table if size >=
> - less memory touched during read_lock()/read_unlock()
> - Better sharing of hash entries between cpus
I'm generally in support of this change, however 2 suggestions:
1) Please allocate the rwlock table dynamically. You can put
#ifdef CONFIG_SMP around this stuff if you wish so that
we don't do silly things like allocate a zero sized table
on non-SMP builds.
Perhaps you might want to similarly abstract out the rwlock
acquisition, "tcp_ehash_lock(unsigned int slot)" and
"tcp_ehash_unlock(unsigned int slot)". It's just an idea.
2) With dynamic allocation, you can consider perhaps dynamic sizing
based upon a) the ehash size b) NR_CPUS or some combination of