net/tls: align non temporal copy to cache lines

Unlike normal TCP code TLS has to touch the cache lines
it copies into to fill header info. On memory-heavy workloads
having non temporal stores and normal accesses targeting
the same cache line leads to significant overhead.

Measured 3% overhead running 3600 round robin connections
with additional memory heavy workload.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Dirk van der Merwe <dirk.vandermerwe@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Jakub Kicinski 2019-09-06 22:30:00 -07:00 committed by David S. Miller
parent e7b159a48b
commit e681cc603a

View File

@ -372,6 +372,31 @@ static int tls_do_allocation(struct sock *sk,
return 0;
}
static int tls_device_copy_data(void *addr, size_t bytes, struct iov_iter *i)
{
size_t pre_copy, nocache;
pre_copy = ~((unsigned long)addr - 1) & (SMP_CACHE_BYTES - 1);
if (pre_copy) {
pre_copy = min(pre_copy, bytes);
if (copy_from_iter(addr, pre_copy, i) != pre_copy)
return -EFAULT;
bytes -= pre_copy;
addr += pre_copy;
}
nocache = round_down(bytes, SMP_CACHE_BYTES);
if (copy_from_iter_nocache(addr, nocache, i) != nocache)
return -EFAULT;
bytes -= nocache;
addr += nocache;
if (bytes && copy_from_iter(addr, bytes, i) != bytes)
return -EFAULT;
return 0;
}
static int tls_push_data(struct sock *sk,
struct iov_iter *msg_iter,
size_t size, int flags,
@ -445,12 +470,10 @@ handle_error:
copy = min_t(size_t, size, (pfrag->size - pfrag->offset));
copy = min_t(size_t, copy, (max_open_record_len - record->len));
if (copy_from_iter_nocache(page_address(pfrag->page) +
pfrag->offset,
copy, msg_iter) != copy) {
rc = -EFAULT;
rc = tls_device_copy_data(page_address(pfrag->page) +
pfrag->offset, copy, msg_iter);
if (rc)
goto handle_error;
}
tls_append_frag(record, pfrag, copy);
size -= copy;