lkml.org 
[lkml]   [2021]   [Apr]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] net/rxrpc: Use BUG_ON instead of if condition followed by BUG.
Date
BUG_ON() uses unlikely in if(), which can be optimized at compile time.

do { if (unlikely(condition)) BUG(); } while (0)

Through disassembly, we can see that brk #0x800 is compiled to the
end of the function.
As you can see below:
......
ffffff8008660bec: d65f03c0 ret
ffffff8008660bf0: d4210000 brk #0x800

Usually, the condition in if () is not satisfied. For the multi-stage
pipeline, we do not need to perform fetch decode and excute operation
on brk instruction.

IMO, this can improve the efficiency of the multi-stage pipeline.

Signed-off-by: zhouchuangao <zhouchuangao@vivo.com>
---
net/rxrpc/call_object.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/net/rxrpc/call_object.c b/net/rxrpc/call_object.c
index 4eb91d95..e5deb6f 100644
--- a/net/rxrpc/call_object.c
+++ b/net/rxrpc/call_object.c
@@ -505,8 +505,7 @@ void rxrpc_release_call(struct rxrpc_sock *rx, struct rxrpc_call *call)
ASSERTCMP(call->state, ==, RXRPC_CALL_COMPLETE);

spin_lock_bh(&call->lock);
- if (test_and_set_bit(RXRPC_CALL_RELEASED, &call->flags))
- BUG();
+ BUG_ON(test_and_set_bit(RXRPC_CALL_RELEASED, &call->flags));
spin_unlock_bh(&call->lock);

rxrpc_put_call_slot(call);
@@ -636,8 +635,7 @@ static void rxrpc_rcu_destroy_call(struct rcu_head *rcu)

if (in_softirq()) {
INIT_WORK(&call->processor, rxrpc_destroy_call);
- if (!rxrpc_queue_work(&call->processor))
- BUG();
+ BUG_ON(!rxrpc_queue_work(&call->processor));
} else {
rxrpc_destroy_call(&call->processor);
}
--
2.7.4
\
 
 \ /
  Last update: 2021-04-29 10:17    [W:0.041 / U:0.072 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site