tegrakernel/kernel/kernel-4.9/rt-patches/0220-net-Use-cpu_chill-inst...

70 lines
2.0 KiB
Diff

From 14e74a16aaa01093ef3008a63f68fa1482a66418 Mon Sep 17 00:00:00 2001
From: Thomas Gleixner <tglx@linutronix.de>
Date: Wed, 7 Mar 2012 21:10:04 +0100
Subject: [PATCH 220/365] net: Use cpu_chill() instead of cpu_relax()
Retry loops on RT might loop forever when the modifying side was
preempted. Use cpu_chill() instead of cpu_relax() to let the system
make progress.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
net/packet/af_packet.c | 5 +++--
net/rds/ib_rdma.c | 3 ++-
2 files changed, 5 insertions(+), 3 deletions(-)
diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
index b5b79f501541..f4959d6f1090 100644
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -63,6 +63,7 @@
#include <linux/if_packet.h>
#include <linux/wireless.h>
#include <linux/kernel.h>
+#include <linux/delay.h>
#include <linux/kmod.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
@@ -702,7 +703,7 @@ static void prb_retire_rx_blk_timer_expired(unsigned long data)
if (BLOCK_NUM_PKTS(pbd)) {
while (atomic_read(&pkc->blk_fill_in_prog)) {
/* Waiting for skb_copy_bits to finish... */
- cpu_relax();
+ cpu_chill();
}
}
@@ -964,7 +965,7 @@ static void prb_retire_current_block(struct tpacket_kbdq_core *pkc,
if (!(status & TP_STATUS_BLK_TMO)) {
while (atomic_read(&pkc->blk_fill_in_prog)) {
/* Waiting for skb_copy_bits to finish... */
- cpu_relax();
+ cpu_chill();
}
}
prb_close_block(pkc, pbd, po, status);
diff --git a/net/rds/ib_rdma.c b/net/rds/ib_rdma.c
index 78d5d68cbbce..9f758494b337 100644
--- a/net/rds/ib_rdma.c
+++ b/net/rds/ib_rdma.c
@@ -34,6 +34,7 @@
#include <linux/slab.h>
#include <linux/rculist.h>
#include <linux/llist.h>
+#include <linux/delay.h>
#include "rds_single_path.h"
#include "ib_mr.h"
@@ -210,7 +211,7 @@ static inline void wait_clean_list_grace(void)
for_each_online_cpu(cpu) {
flag = &per_cpu(clean_list_grace, cpu);
while (test_bit(CLEAN_LIST_BUSY_BIT, flag))
- cpu_relax();
+ cpu_chill();
}
}
--
2.28.0