From: Tim Chen <tim.c.chen@linux.intel.com>
To: Peter Zijlstra <peterz@infradead.org>,
Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@elte.hu>, Andi Kleen <andi@firstfloor.org>,
"H. Peter Anvin" <hpa@zytor.com>,
Thomas Gleixner <tglx@linutronix.de>,
"Srivatsa S.Bhat" <srivatsa.bhat@linux.vnet.ibm.com>,
linux-kernel@vger.kernel.org
Subject: [PATCH] smp: Remove CSD_FLAG_WAIT flag that's unused
Date: Fri, 27 Feb 2015 12:36:13 -0800 [thread overview]
Message-ID: <1425069373.9530.155.camel@schen9-desk2.jf.intel.com> (raw)
The CSD_FLAG_WAIT is not serving any useful purpose as we do not use
its value to decide if we are going to wait for a smp call to complete.
We also never cleared it properly when we are done waiting to indicate
that the wait is over. So the WARNING debug check in csd_unlock is
also not serving useful purpose. Propose here to remove it to clean up
the code.
Thanks.
Tim
Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com>
---
kernel/smp.c | 6 +-----
1 file changed, 1 insertion(+), 5 deletions(-)
diff --git a/kernel/smp.c b/kernel/smp.c
index f38a1e6..b65420d 100644
--- a/kernel/smp.c
+++ b/kernel/smp.c
@@ -19,7 +19,6 @@
enum {
CSD_FLAG_LOCK = 0x01,
- CSD_FLAG_WAIT = 0x02,
};
struct call_function_data {
@@ -126,7 +125,7 @@ static void csd_lock(struct call_single_data *csd)
static void csd_unlock(struct call_single_data *csd)
{
- WARN_ON((csd->flags & CSD_FLAG_WAIT) && !(csd->flags & CSD_FLAG_LOCK));
+ WARN_ON(!(csd->flags & CSD_FLAG_LOCK));
/*
* ensure we're all done before releasing data:
@@ -173,9 +172,6 @@ static int generic_exec_single(int cpu, struct call_single_data *csd,
csd->func = func;
csd->info = info;
- if (wait)
- csd->flags |= CSD_FLAG_WAIT;
-
/*
* The list addition should be visible before sending the IPI
* handler locks the list to pull the entry off it because of
--
1.9.3
next reply other threads:[~2015-02-27 20:36 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-02-27 20:36 Tim Chen [this message]
2015-02-27 22:09 ` Peter Zijlstra
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