From: Jakub Kicinski <jakub.kicinski@netronome.com>
Date: Sun, 6 Oct 2019 21:09:27 -0700
Subject: net: sockmap: use bitmap for copy info
Patch-mainline: v5.5-rc1
Git-commit: 163ab96b52ae2bb2d8f188cd29f0b570610f9007
References: bsc#1154353
Don't use bool array in struct sk_msg_sg, save 12 bytes.
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>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
include/linux/skmsg.h | 12 ++++++++----
net/core/filter.c | 4 ++--
2 files changed, 10 insertions(+), 6 deletions(-)
--- a/include/linux/skmsg.h
+++ b/include/linux/skmsg.h
@@ -28,13 +28,14 @@ struct sk_msg_sg {
u32 end;
u32 size;
u32 copybreak;
- bool copy[MAX_MSG_FRAGS];
+ unsigned long copy;
/* The extra element is used for chaining the front and sections when
* the list becomes partitioned (e.g. end < start). The crypto APIs
* require the chaining.
*/
struct scatterlist data[MAX_MSG_FRAGS + 1];
};
+static_assert(BITS_PER_LONG >= MAX_MSG_FRAGS);
/* UAPI in filter.c depends on struct sk_msg_sg being first element. */
struct sk_msg {
@@ -230,7 +231,7 @@ static inline void sk_msg_compute_data_p
{
struct scatterlist *sge = sk_msg_elem(msg, msg->sg.start);
- if (msg->sg.copy[msg->sg.start]) {
+ if (test_bit(msg->sg.start, &msg->sg.copy)) {
msg->data = NULL;
msg->data_end = NULL;
} else {
@@ -249,7 +250,7 @@ static inline void sk_msg_page_add(struc
sg_set_page(sge, page, len, offset);
sg_unmark_end(sge);
- msg->sg.copy[msg->sg.end] = true;
+ __set_bit(msg->sg.end, &msg->sg.copy);
msg->sg.size += len;
sk_msg_iter_next(msg, end);
}
@@ -257,7 +258,10 @@ static inline void sk_msg_page_add(struc
static inline void sk_msg_sg_copy(struct sk_msg *msg, u32 i, bool copy_state)
{
do {
- msg->sg.copy[i] = copy_state;
+ if (copy_state)
+ __set_bit(i, &msg->sg.copy);
+ else
+ __clear_bit(i, &msg->sg.copy);
sk_msg_iter_var_next(i);
if (i == msg->sg.end)
break;
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -2245,7 +2245,7 @@ BPF_CALL_4(bpf_msg_pull_data, struct sk_
* account for the headroom.
*/
bytes_sg_total = start - offset + bytes;
- if (!msg->sg.copy[i] && bytes_sg_total <= len)
+ if (!test_bit(i, &msg->sg.copy) && bytes_sg_total <= len)
goto out;
/* At this point we need to linearize multiple scatterlist
@@ -2450,7 +2450,7 @@ BPF_CALL_4(bpf_msg_push_data, struct sk_
/* Place newly allocated data buffer */
sk_mem_charge(msg->sk, len);
msg->sg.size += len;
- msg->sg.copy[new] = false;
+ __clear_bit(new, &msg->sg.copy);
sg_set_page(&msg->sg.data[new], page, len + copy, 0);
if (rsge.length) {
get_page(sg_page(&rsge));