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From:   Gao Xiang <hsiangkao@linux.alibaba.com>
To:     linux-erofs@lists.ozlabs.org
Cc:     LKML <linux-kernel@vger.kernel.org>,
        Gao Xiang <hsiangkao@linux.alibaba.com>,
        Sandeep Dhavale <dhavale@google.com>
Subject: [PATCH] erofs: use HIPRI by default if per-cpu kthreads are enabled
Date:   Mon, 22 May 2023 17:21:41 +0800
Message-Id: <20230522092141.124290-1-hsiangkao@linux.alibaba.com>
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As Sandeep shown [1], high priority RT per-cpu kthreads are
typically helpful for Android scenarios to minimize the scheduling
latencies.

Switch EROFS_FS_PCPU_KTHREAD_HIPRI on by default if
EROFS_FS_PCPU_KTHREAD is on since it's the typical use cases for
EROFS_FS_PCPU_KTHREAD.

Also clean up unneeded sched_set_normal().

[1] https://lore.kernel.org/r/CAB=BE-SBtO6vcoyLNA9F-9VaN5R0t3o_Zn+FW8GbO6wyUqFneQ@mail.gmail.com
Cc: Sandeep Dhavale <dhavale@google.com>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
---
 fs/erofs/Kconfig | 1 +
 fs/erofs/zdata.c | 2 --
 2 files changed, 1 insertion(+), 2 deletions(-)

diff --git a/fs/erofs/Kconfig b/fs/erofs/Kconfig
index 704fb59577e0..f259d92c9720 100644
--- a/fs/erofs/Kconfig
+++ b/fs/erofs/Kconfig
@@ -121,6 +121,7 @@ config EROFS_FS_PCPU_KTHREAD
 config EROFS_FS_PCPU_KTHREAD_HIPRI
 	bool "EROFS high priority per-CPU kthread workers"
 	depends on EROFS_FS_ZIP && EROFS_FS_PCPU_KTHREAD
+	default y
 	help
 	  This permits EROFS to configure per-CPU kthread workers to run
 	  at higher priority.
diff --git a/fs/erofs/zdata.c b/fs/erofs/zdata.c
index 92f3a01262cf..3ba505434f03 100644
--- a/fs/erofs/zdata.c
+++ b/fs/erofs/zdata.c
@@ -367,8 +367,6 @@ static struct kthread_worker *erofs_init_percpu_worker(int cpu)
 		return worker;
 	if (IS_ENABLED(CONFIG_EROFS_FS_PCPU_KTHREAD_HIPRI))
 		sched_set_fifo_low(worker->task);
-	else
-		sched_set_normal(worker->task, 0);
 	return worker;
 }
 
-- 
2.24.4