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From: "Peter Wang (王信友)" <peter.wang@mediatek.com>
To: "linux-scsi@vger.kernel.org" <linux-scsi@vger.kernel.org>,
	"jejb@linux.ibm.com" <jejb@linux.ibm.com>,
	"avri.altman@sandisk.com" <avri.altman@sandisk.com>,
	"bvanassche@acm.org" <bvanassche@acm.org>,
	"alim.akhtar@samsung.com" <alim.akhtar@samsung.com>,
	"martin.petersen@oracle.com" <martin.petersen@oracle.com>
Cc: "Alice Chao (趙珮均)" <Alice.Chao@mediatek.com>,
	"Eddie Huang (黃智傑)" <eddie.huang@mediatek.com>,
	"CC Chou (周志杰)" <cc.chou@mediatek.com>,
	"Ed Tsai (蔡宗軒)" <Ed.Tsai@mediatek.com>,
	wsd_upstream <wsd_upstream@mediatek.com>,
	"Chaotian Jing (井朝天)" <Chaotian.Jing@mediatek.com>,
	"Chun-Hung Wu (巫駿宏)" <Chun-hung.Wu@mediatek.com>,
	"Naomi Chu (朱詠田)" <Naomi.Chu@mediatek.com>,
	"linux-mediatek@lists.infradead.org"
	<linux-mediatek@lists.infradead.org>,
	"Tun-yu Yu (游敦聿)" <Tun-yu.Yu@mediatek.com>
Subject: Re: [PATCH v1] ufs: core: Avoid IRQ thread wakeup during active UIC command
Date: Thu, 5 Mar 2026 03:27:20 +0000	[thread overview]
Message-ID: <fa949b2c2f9d23fa112f8b37377ca2f23c5bb258.camel@mediatek.com> (raw)
In-Reply-To: <ab2de228-47f0-40b0-b586-c970a9c0652a@acm.org>

On Wed, 2026-03-04 at 08:43 -0600, Bart Van Assche wrote:
> A context switch takes somewhere between 1 and 10 microseconds.
> That is several orders of magnitude below the UIC command timeout.
> Something else must be causing the observed UIC timeouts.
> 
> Thanks,
> 
> Bart.

Hi Bart,

The main reason is not context switch time.
The problem is that a threaded IRQ handler can be preempted
by a regular IRQ.
When the system is busy, for example during kernel boot,
there are many other module IRQs present in the system.

Thanks
Peter

  reply	other threads:[~2026-03-05  3:27 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-03-04  7:12 [PATCH v1] ufs: core: Avoid IRQ thread wakeup during active UIC command peter.wang
2026-03-04 14:43 ` Bart Van Assche
2026-03-05  3:27   ` Peter Wang (王信友) [this message]
2026-03-05 12:17     ` Bart Van Assche
2026-03-06  3:49       ` Peter Wang (王信友)

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