From: Eric Dumazet <edumazet@google.com>
To: Christoph Hellwig <hch@lst.de>
Cc: linux-kernel <linux-kernel@vger.kernel.org>,
Eric Dumazet <edumazet@google.com>,
Eric Dumazet <eric.dumazet@gmail.com>,
Corentin Labbe <clabbe@baylibre.com>,
Marek Szyprowski <m.szyprowski@samsung.com>
Subject: [PATCH] dma-debug: add a schedule point in debug_dma_dump_mappings()
Date: Mon, 28 Oct 2019 14:56:46 -0700 [thread overview]
Message-ID: <20191028215646.16638-1-edumazet@google.com> (raw)
debug_dma_dump_mappings() can take a lot of cpu cycles :
lpk43:/# time wc -l /sys/kernel/debug/dma-api/dump
163435 /sys/kernel/debug/dma-api/dump
real 0m0.463s
user 0m0.003s
sys 0m0.459s
Let's add a cond_resched() to avoid holding cpu for too long.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Corentin Labbe <clabbe@baylibre.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
---
kernel/dma/debug.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/kernel/dma/debug.c b/kernel/dma/debug.c
index 099002d84f466af0a8e421d035ac8eb119e08bd8..4ad74f5987ea9e95f9bb5e2d1592254e367d24fb 100644
--- a/kernel/dma/debug.c
+++ b/kernel/dma/debug.c
@@ -420,6 +420,7 @@ void debug_dma_dump_mappings(struct device *dev)
}
spin_unlock_irqrestore(&bucket->lock, flags);
+ cond_resched();
}
}
--
2.24.0.rc0.303.g954a862665-goog
next reply other threads:[~2019-10-28 21:56 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-10-28 21:56 Eric Dumazet [this message]
2019-10-30 18:12 ` [PATCH] dma-debug: add a schedule point in debug_dma_dump_mappings() Christoph Hellwig
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=20191028215646.16638-1-edumazet@google.com \
--to=edumazet@google.com \
--cc=clabbe@baylibre.com \
--cc=eric.dumazet@gmail.com \
--cc=hch@lst.de \
--cc=linux-kernel@vger.kernel.org \
--cc=m.szyprowski@samsung.com \
/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