From: "Alexandra N. Kossovsky" <Alexandra.Kossovsky-mK/T7fl7eHLILq5++fvS8w@public.gmane.org>
To: iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org
Cc: Robert Stonehouse <rstonehouse-s/n/eUQHGBpZroRs9YW3xA@public.gmane.org>
Subject: atomic context for iommu_map call
Date: Fri, 22 Jun 2012 15:28:14 +0400 [thread overview]
Message-ID: <20120622112812.GV8140@oktetlabs.ru> (raw)
Hello.
It is not clear from the documentation if iommu_map()/iommu_unmap()
functions may be called from atomic context.
In case of Intel IOMMU, it works; in case of AMD IOMMU, it does not.
Was it done by purpose? May I propose a patch for AMD IOMMU replacing
GFP_KERNEL by GFP_ATOMIC to make things better?
We use IOMMU API in OpenOnload project http://www.openonload.org/,
and we get better latency with Intel IOMMU because we are not
forced to use threaded IRQ.
--
Alexandra N. Kossovsky
OKTET Labs (http://www.oktetlabs.ru/)
next reply other threads:[~2012-06-22 11:28 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-06-22 11:28 Alexandra N. Kossovsky [this message]
[not found] ` <20120622112812.GV8140-mK/T7fl7eHLILq5++fvS8w@public.gmane.org>
2012-06-25 18:35 ` atomic context for iommu_map call Chris Wright
2012-06-26 8:58 ` Joerg Roedel
[not found] ` <20120626085853.GX2624-5C7GfCeVMHo@public.gmane.org>
2012-06-26 9:08 ` Alexandra N. Kossovsky
2012-06-26 18:07 ` Chris Wright
[not found] ` <20120626180743.GV15796-JyIX8gxvWYPr2PDY2+4mTGD2FQJk+8+b@public.gmane.org>
2012-07-09 9:42 ` Joerg Roedel
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