From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751370AbdEBQY2 (ORCPT ); Tue, 2 May 2017 12:24:28 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:46451 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1750854AbdEBQYY (ORCPT ); Tue, 2 May 2017 12:24:24 -0400 From: "Paul E. McKenney" To: linux-kernel@vger.kernel.org Cc: mingo@kernel.org, jiangshanlai@gmail.com, dipankar@in.ibm.com, akpm@linux-foundation.org, mathieu.desnoyers@efficios.com, josh@joshtriplett.org, tglx@linutronix.de, peterz@infradead.org, rostedt@goodmis.org, dhowells@redhat.com, edumazet@google.com, fweisbec@gmail.com, oleg@redhat.com, bobby.prani@gmail.com, "Paul E. McKenney" , Linus Torvalds Subject: [PATCH tip/core/rcu 2/3] rcu: Open-code the rcu_cblist_n_cbs() function Date: Tue, 2 May 2017 09:24:14 -0700 X-Mailer: git-send-email 2.5.2 In-Reply-To: <20170502162114.GA12193@linux.vnet.ibm.com> References: <20170502162114.GA12193@linux.vnet.ibm.com> X-TM-AS-GCONF: 00 x-cbid: 17050216-0056-0000-0000-0000035544C4 X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00007012; HX=3.00000240; KW=3.00000007; PH=3.00000004; SC=3.00000208; SDB=6.00855251; UDB=6.00423254; IPR=6.00634412; BA=6.00005322; NDR=6.00000001; ZLA=6.00000005; ZF=6.00000009; ZB=6.00000000; ZP=6.00000000; ZH=6.00000000; ZU=6.00000002; MB=3.00015271; XFM=3.00000014; UTC=2017-05-02 16:24:20 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17050216-0057-0000-0000-0000078B63BF Message-Id: <1493742255-13222-2-git-send-email-paulmck@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2017-05-02_10:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=1 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1703280000 definitions=main-1705020092 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Because the rcu_cblist_n_cbs() just samples the ->len counter, and because the rcu_cblist structure is quite straightforward, it makes sense to open-code rcu_cblist_n_cbs(p) as p->len, cutting out a level of indirection. This commit makes this change. Reported-by: Ingo Molnar Signed-off-by: Paul E. McKenney Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Linus Torvalds --- kernel/rcu/rcu_segcblist.h | 6 ------ kernel/rcu/tree.c | 9 ++++----- kernel/rcu/tree_plugin.h | 2 +- kernel/rcu/tree_trace.c | 2 +- 4 files changed, 6 insertions(+), 13 deletions(-) diff --git a/kernel/rcu/rcu_segcblist.h b/kernel/rcu/rcu_segcblist.h index 7d18d41f0116..424a6b230921 100644 --- a/kernel/rcu/rcu_segcblist.h +++ b/kernel/rcu/rcu_segcblist.h @@ -22,12 +22,6 @@ #include -/* Return number of callbacks in simple callback list. */ -static inline long rcu_cblist_n_cbs(struct rcu_cblist *rclp) -{ - return rclp->len; -} - /* Return number of lazy callbacks in simple callback list. */ static inline long rcu_cblist_n_lazy_cbs(struct rcu_cblist *rclp) { diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index 35152414760d..942d529fccbc 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -2633,9 +2633,8 @@ static void rcu_adopt_orphan_cbs(struct rcu_state *rsp, unsigned long flags) return; /* Do the accounting first. */ - rdp->n_cbs_adopted += rcu_cblist_n_cbs(&rsp->orphan_done); - if (rcu_cblist_n_lazy_cbs(&rsp->orphan_done) != - rcu_cblist_n_cbs(&rsp->orphan_done)) + rdp->n_cbs_adopted += rsp->orphan_done.len; + if (rcu_cblist_n_lazy_cbs(&rsp->orphan_done) != rsp->orphan_done.len) rcu_idle_count_callbacks_posted(); rcu_segcblist_insert_count(&rdp->cblist, &rsp->orphan_done); @@ -2792,14 +2791,14 @@ static void rcu_do_batch(struct rcu_state *rsp, struct rcu_data *rdp) * Stop only if limit reached and CPU has something to do. * Note: The rcl structure counts down from zero. */ - if (-rcu_cblist_n_cbs(&rcl) >= bl && + if (-rcl.len >= bl && (need_resched() || (!is_idle_task(current) && !rcu_is_callbacks_kthread()))) break; } local_irq_save(flags); - count = -rcu_cblist_n_cbs(&rcl); + count = -rcl.len; trace_rcu_batch_end(rsp->name, count, !!rcl.head, need_resched(), is_idle_task(current), rcu_is_callbacks_kthread()); diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h index 6b4b1f8a272d..7ebe357df155 100644 --- a/kernel/rcu/tree_plugin.h +++ b/kernel/rcu/tree_plugin.h @@ -1934,7 +1934,7 @@ static bool __maybe_unused rcu_nocb_adopt_orphan_cbs(struct rcu_state *rsp, struct rcu_data *rdp, unsigned long flags) { - long ql = rcu_cblist_n_cbs(&rsp->orphan_done); + long ql = rsp->orphan_done.len; long qll = rcu_cblist_n_lazy_cbs(&rsp->orphan_done); /* If this is not a no-CBs CPU, tell the caller to do it the old way. */ diff --git a/kernel/rcu/tree_trace.c b/kernel/rcu/tree_trace.c index 30c5bf89ee58..b7743aa2965f 100644 --- a/kernel/rcu/tree_trace.c +++ b/kernel/rcu/tree_trace.c @@ -278,7 +278,7 @@ static void print_one_rcu_state(struct seq_file *m, struct rcu_state *rsp) rsp->n_force_qs - rsp->n_force_qs_ngp, READ_ONCE(rsp->n_force_qs_lh), rcu_cblist_n_lazy_cbs(&rsp->orphan_done), - rcu_cblist_n_cbs(&rsp->orphan_done)); + rsp->orphan_done.len); for (rnp = &rsp->node[0]; rnp - &rsp->node[0] < rcu_num_nodes; rnp++) { if (rnp->level != level) { seq_puts(m, "\n"); -- 2.5.2