public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Tejun Heo <tj@kernel.org>
To: jiangshanlai@gmail.com
Cc: torvalds@linux-foundation.org, peterz@infradead.org,
	linux-kernel@vger.kernel.org, kernel-team@meta.com,
	Tejun Heo <tj@kernel.org>
Subject: [PATCH 2/5] workqueue: Re-order struct worker fields
Date: Tue, 18 Apr 2023 10:51:56 -1000	[thread overview]
Message-ID: <20230418205159.724789-3-tj@kernel.org> (raw)
In-Reply-To: <20230418205159.724789-1-tj@kernel.org>

struct worker was laid out with the intent that all fields that are modified
for each work item execution are in the first cacheline. However, this
hasn't been true for a while with the addition of ->last_func. Let's just
collect hot fields together at the top.

Move ->sleeping in the hole after ->current_color and move ->lst_func right
below. While at it, drop the cacheline comment which isn't useful anymore.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
---
 kernel/workqueue_internal.h | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/kernel/workqueue_internal.h b/kernel/workqueue_internal.h
index b3b4b2b41d93..902459b328de 100644
--- a/kernel/workqueue_internal.h
+++ b/kernel/workqueue_internal.h
@@ -32,9 +32,12 @@ struct worker {
 	work_func_t		current_func;	/* L: current_work's fn */
 	struct pool_workqueue	*current_pwq;	/* L: current_work's pwq */
 	unsigned int		current_color;	/* L: current_work's color */
-	struct list_head	scheduled;	/* L: scheduled works */
+	int			sleeping;	/* None */
+
+	/* used by the scheduler to determine a worker's last known identity */
+	work_func_t		last_func;	/* L: last work's fn */
 
-	/* 64 bytes boundary on 64bit, 32 on 32bit */
+	struct list_head	scheduled;	/* L: scheduled works */
 
 	struct task_struct	*task;		/* I: worker task */
 	struct worker_pool	*pool;		/* A: the associated pool */
@@ -45,7 +48,6 @@ struct worker {
 	unsigned long		last_active;	/* L: last active timestamp */
 	unsigned int		flags;		/* X: flags */
 	int			id;		/* I: worker id */
-	int			sleeping;	/* None */
 
 	/*
 	 * Opaque string set with work_set_desc().  Printed out with task
@@ -55,9 +57,6 @@ struct worker {
 
 	/* used only by rescuers to point to the target workqueue */
 	struct workqueue_struct	*rescue_wq;	/* I: the workqueue to rescue */
-
-	/* used by the scheduler to determine a worker's last known identity */
-	work_func_t		last_func;
 };
 
 /**
-- 
2.40.0


  parent reply	other threads:[~2023-04-18 20:52 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-04-18 20:51 [PATCHSET wq/for-6.5] workqueue: Implement automatic CPU intensive detection and add monitoring Tejun Heo
2023-04-18 20:51 ` [PATCH 1/5] workqueue, sched: Notify workqueue of scheduling of RUNNING tasks Tejun Heo
2023-04-18 20:51 ` Tejun Heo [this message]
2023-04-18 20:51 ` [PATCH 3/5] workqueue: Move worker_set/clr_flags() upwards Tejun Heo
2023-04-18 20:51 ` [PATCH 4/5] workqueue: Automatically mark CPU-hogging work items CPU_INTENSIVE Tejun Heo
2023-04-23  3:23   ` Lai Jiangshan
2023-04-24 15:29     ` Tejun Heo
2023-04-25 13:12   ` Peter Zijlstra
2023-04-28 15:19     ` Tejun Heo
2023-04-18 20:51 ` [PATCH 5/5] workqueue: Add pwq->stats[] and a monitoring script Tejun Heo
     [not found] ` <20230419014552.1410-1-hdanton@sina.com>
2023-04-19 15:45   ` [PATCH 4/5] workqueue: Automatically mark CPU-hogging work items CPU_INTENSIVE Tejun Heo

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20230418205159.724789-3-tj@kernel.org \
    --to=tj@kernel.org \
    --cc=jiangshanlai@gmail.com \
    --cc=kernel-team@meta.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=peterz@infradead.org \
    --cc=torvalds@linux-foundation.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox