From: arnd@arndb.de (Arnd Bergmann)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH v4 2/2] iommu/arm-smmu: add support for iova_to_phys through ATS1PR
Date: Wed, 01 Oct 2014 10:27:27 +0200 [thread overview]
Message-ID: <61772524.IxG1939KJq@wuerfel> (raw)
In-Reply-To: <1412126893-15796-3-git-send-email-mitchelh@codeaurora.org>
On Tuesday 30 September 2014 18:28:13 Mitchel Humpherys wrote:
> + if (readl_poll_timeout_atomic(cb_base + ARM_SMMU_CB_ATSR, tmp,
> + !(tmp & ATSR_ACTIVE), 50, 100)) {
>
This looks really bad.
You are doing up to 50 100us delays, each of which can be much longer,
so you can do up to 10ms total delay with interrupts disabled.
Don't do that.
Arnd
next prev parent reply other threads:[~2014-10-01 8:27 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-10-01 1:28 [PATCH v4 0/2] iommu/arm-smmu: hard iova_to_phys Mitchel Humpherys
2014-10-01 1:28 ` [PATCH v4 1/2] iopoll: Introduce memory-mapped IO polling macros Mitchel Humpherys
2014-10-01 8:25 ` Arnd Bergmann
2014-10-08 1:47 ` Mitchel Humpherys
2014-10-08 13:40 ` Arnd Bergmann
2014-10-10 19:44 ` Mitchel Humpherys
2014-10-10 19:50 ` Arnd Bergmann
2014-10-10 20:24 ` Mitchel Humpherys
2014-10-09 22:45 ` Mitchel Humpherys
2014-10-01 1:28 ` [PATCH v4 2/2] iommu/arm-smmu: add support for iova_to_phys through ATS1PR Mitchel Humpherys
2014-10-01 8:27 ` Arnd Bergmann [this message]
2014-10-01 19:52 ` Mitchel Humpherys
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=61772524.IxG1939KJq@wuerfel \
--to=arnd@arndb.de \
--cc=linux-arm-kernel@lists.infradead.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