Add sock_alloc_send_pskb_noinit(), which is similar to
sock_alloc_send_pskb(), but allocates with __GFP_NO_AUTOINIT.
This helps reduce the slowdown on hackbench in the init_on_alloc mode
from 6.84% to 3.45%.
Slowdown for the initialization features compared to init_on_free=0,
init_on_alloc=0:
hackbench, init_on_free=1: +7.71% sys time (st.err 0.45%)
hackbench, init_on_alloc=1: +3.45% sys time (st.err 0.86%)
Linux build with -j12, init_on_free=1: +8.34% wall time (st.err 0.39%)
Linux build with -j12, init_on_free=1: +24.13% sys time (st.err 0.47%)
Linux build with -j12, init_on_alloc=1: -0.04% wall time (st.err 0.46%)
Linux build with -j12, init_on_alloc=1: +0.50% sys time (st.err 0.45%)
The slowdown for init_on_free=0, init_on_alloc=0 compared to the
baseline is within the standard error.
Signed-off-by: Alexander Potapenko <glider@xxxxxxxxxx>
To: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
To: Christoph Lameter <cl@xxxxxxxxx>
To: Kees Cook <keescook@xxxxxxxxxxxx>
Cc: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
Cc: James Morris <jmorris@xxxxxxxxx>
Cc: "Serge E. Hallyn" <serge@xxxxxxxxxx>
Cc: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
Cc: Kostya Serebryany <kcc@xxxxxxxxxx>
Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx>
Cc: Sandeep Patil <sspatil@xxxxxxxxxxx>
Cc: Laura Abbott <labbott@xxxxxxxxxx>
Cc: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
Cc: Jann Horn <jannh@xxxxxxxxxx>
Cc: Mark Rutland <mark.rutland@xxxxxxx>
Cc: linux-mm@xxxxxxxxx
Cc: linux-security-module@xxxxxxxxxxxxxxx
Cc: kernel-hardening@xxxxxxxxxxxxxxxxxx
---
v2:
- changed __GFP_NOINIT to __GFP_NO_AUTOINIT
---
include/net/sock.h | 5 +++++
net/core/sock.c | 29 +++++++++++++++++++++++++----
net/unix/af_unix.c | 13 +++++++------
3 files changed, 37 insertions(+), 10 deletions(-)
diff --git a/include/net/sock.h b/include/net/sock.h
index 4d208c0f9c14..0dcb90a0c14d 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -1626,6 +1626,11 @@ struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
unsigned long data_len, int noblock,
int *errcode, int max_page_order);
+struct sk_buff *sock_alloc_send_pskb_noinit(struct sock *sk,
+ unsigned long header_len,
+ unsigned long data_len,
+ int noblock, int *errcode,
+ int max_page_order);
void *sock_kmalloc(struct sock *sk, int size, gfp_t priority);
void sock_kfree_s(struct sock *sk, void *mem, int size);
void sock_kzfree_s(struct sock *sk, void *mem, int size);
diff --git a/net/core/sock.c b/net/core/sock.c
index 9ceb90c875bc..7c24b70b7069 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -2192,9 +2192,11 @@ static long sock_wait_for_wmem(struct sock *sk, long timeo)
* Generic send/receive buffer handlers
*/
-struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
- unsigned long data_len, int noblock,
- int *errcode, int max_page_order)
+struct sk_buff *sock_alloc_send_pskb_internal(struct sock *sk,
+ unsigned long header_len,
+ unsigned long data_len,
+ int noblock, int *errcode,
+ int max_page_order, gfp_t gfp)
{
struct sk_buff *skb;
long timeo;
@@ -2223,7 +2225,7 @@ struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
timeo = sock_wait_for_wmem(sk, timeo);
}
skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
- errcode, sk->sk_allocation);
+ errcode, sk->sk_allocation | gfp);
if (skb)
skb_set_owner_w(skb, sk);
return skb;
@@ -2234,8 +2236,27 @@ struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
*errcode = err;
return NULL;
}
+
+struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
+ unsigned long data_len, int noblock,
+ int *errcode, int max_page_order)
+{
+ return sock_alloc_send_pskb_internal(sk, header_len, data_len,
+ noblock, errcode, max_page_order, /*gfp*/0);
+}
EXPORT_SYMBOL(sock_alloc_send_pskb);
+struct sk_buff *sock_alloc_send_pskb_noinit(struct sock *sk,
+ unsigned long header_len,
+ unsigned long data_len,
+ int noblock, int *errcode,
+ int max_page_order)
+{
+ return sock_alloc_send_pskb_internal(sk, header_len, data_len,
+ noblock, errcode, max_page_order, /*gfp*/__GFP_NO_AUTOINIT);
+}
+EXPORT_SYMBOL(sock_alloc_send_pskb_noinit);
+
struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
int noblock, int *errcode)
{
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index e68d7454f2e3..a4c15620b66d 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -1627,9 +1627,9 @@ static int unix_dgram_sendmsg(struct socket *sock, struct msghdr *msg,
BUILD_BUG_ON(SKB_MAX_ALLOC < PAGE_SIZE);
}
- skb = sock_alloc_send_pskb(sk, len - data_len, data_len,
- msg->msg_flags & MSG_DONTWAIT, &err,
- PAGE_ALLOC_COSTLY_ORDER);
+ skb = sock_alloc_send_pskb_noinit(sk, len - data_len, data_len,
+ msg->msg_flags & MSG_DONTWAIT, &err,
+ PAGE_ALLOC_COSTLY_ORDER);
if (skb == NULL)
goto out;
@@ -1824,9 +1824,10 @@ static int unix_stream_sendmsg(struct socket *sock, struct msghdr *msg,
data_len = min_t(size_t, size, PAGE_ALIGN(data_len));
- skb = sock_alloc_send_pskb(sk, size - data_len, data_len,
- msg->msg_flags & MSG_DONTWAIT, &err,
- get_order(UNIX_SKB_FRAGS_SZ));
+ skb = sock_alloc_send_pskb_noinit(sk, size - data_len, data_len,
+ msg->msg_flags & MSG_DONTWAIT,
+ &err,
+ get_order(UNIX_SKB_FRAGS_SZ));
if (!skb)
goto out_err;
--
2.21.0.1020.gf2820cf01a-goog
