netdev - [PATCH 2/2] net/core: remove explicit do_softirq() from busy_poll

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Date:   Fri, 16 Jun 2017 19:24:00 +0200
From:   Sebastian Andrzej Siewior <bigeasy@...utronix.de>
To:     Eric Dumazet <edumazet@...gle.com>
Cc:     netdev@...r.kernel.org, "David S. Miller" <davem@...emloft.net>,
        Thomas Gleixner <tglx@...utronix.de>,
        Sebastian Andrzej Siewior <bigeasy@...utronix.de>
Subject: [PATCH 2/2] net/core: remove explicit do_softirq() from busy_poll_stop()

Since commit 217f69743681 ("net: busy-poll: allow preemption in
sk_busy_loop()") there is an explicit do_softirq() invocation after
local_bh_enable() has been invoked.
I don't understand why we need this because local_bh_enable() will
invoke do_softirq() once the softirq counter reached zero and we have
softirq-related work pending.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@...utronix.de>
---
 net/core/dev.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/net/core/dev.c b/net/core/dev.c
index b1f8a89322bd..447d37fe89e6 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -5281,8 +5281,6 @@ static void busy_poll_stop(struct napi_struct *napi, void *have_poll_lock)
 	if (rc == BUSY_POLL_BUDGET)
 		__napi_schedule(napi);
 	local_bh_enable();
-	if (local_softirq_pending())
-		do_softirq();
 }
 
 void napi_busy_loop(unsigned int napi_id,
-- 
2.11.0