From: Christoph Hellwig <hch@infradead.org>
To: Jan Beulich <jbeulich@suse.com>
Cc: Juergen Gross <jgross@suse.com>,
Boris Ostrovsky <boris.ostrovsky@oracle.com>,
Stefano Stabellini <sstabellini@kernel.org>,
lkml <linux-kernel@vger.kernel.org>,
"xen-devel@lists.xenproject.org" <xen-devel@lists.xenproject.org>
Subject: Re: [PATCH 04/12] swiotlb-xen: ensure to issue well-formed XENMEM_exchange requests
Date: Wed, 8 Sep 2021 07:57:15 +0100 [thread overview]
Message-ID: <YThey/iyCxi5NUwC@infradead.org> (raw)
In-Reply-To: <397bf325-f81e-e104-6142-e8c9c4955475@suse.com>
On Tue, Sep 07, 2021 at 02:05:32PM +0200, Jan Beulich wrote:
> While the hypervisor hasn't been enforcing this, we would still better
> avoid issuing requests with GFNs not aligned to the requested order.
>
> Signed-off-by: Jan Beulich <jbeulich@suse.com>
> ---
> I wonder how useful it is to include the alignment in the panic()
> message. I further wonder how useful it is to wrap "bytes" in
> PAGE_ALIGN(), when it is a multiple of a segment's size anyway (or at
> least was supposed to be, prior to "swiotlb-xen: maintain slab count
> properly").
>
> --- a/drivers/xen/swiotlb-xen.c
> +++ b/drivers/xen/swiotlb-xen.c
> @@ -231,10 +231,10 @@ retry:
> /*
> * Get IO TLB memory from any location.
> */
> - start = memblock_alloc(PAGE_ALIGN(bytes), PAGE_SIZE);
> + start = memblock_alloc(PAGE_ALIGN(bytes), IO_TLB_SEGSIZE << IO_TLB_SHIFT);
> if (!start)
> - panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
> - __func__, PAGE_ALIGN(bytes), PAGE_SIZE);
> + panic("%s: Failed to allocate %lu bytes align=%#x\n",
> + __func__, PAGE_ALIGN(bytes), IO_TLB_SEGSIZE << IO_TLB_SHIFT);
CAn you avoid the overly long lines here? A good way to make it more
readable would be a variable to hold the byte count.
next prev parent reply other threads:[~2021-09-08 6:58 UTC|newest]
Thread overview: 45+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-09-07 12:03 [PATCH 00/12] swiotlb-xen: fixes and adjustments Jan Beulich
2021-09-07 12:04 ` [PATCH 01/12] swiotlb-xen: avoid double free Jan Beulich
2021-09-08 6:48 ` Christoph Hellwig
2021-09-10 22:55 ` Stefano Stabellini
2021-09-07 12:04 ` [PATCH 02/12] swiotlb-xen: fix late init retry Jan Beulich
2021-09-08 6:50 ` Christoph Hellwig
2021-09-07 12:05 ` [PATCH 03/12] swiotlb-xen: maintain slab count properly Jan Beulich
2021-09-08 6:53 ` Christoph Hellwig
2021-09-10 23:10 ` Stefano Stabellini
2021-09-07 12:05 ` [PATCH 04/12] swiotlb-xen: ensure to issue well-formed XENMEM_exchange requests Jan Beulich
2021-09-08 6:57 ` Christoph Hellwig [this message]
2021-09-08 9:16 ` Jan Beulich
2021-09-10 23:14 ` Stefano Stabellini
2021-09-13 7:17 ` Jan Beulich
2021-09-13 20:31 ` Stefano Stabellini
2021-09-14 9:11 ` Jan Beulich
2021-09-15 1:22 ` Stefano Stabellini
2021-09-15 1:54 ` Stefano Stabellini
2021-09-15 8:21 ` Jan Beulich
2021-09-07 12:05 ` [PATCH 05/12] swiotlb-xen: suppress certain init retries Jan Beulich
2021-09-08 6:58 ` Christoph Hellwig
2021-09-10 23:18 ` Stefano Stabellini
2021-09-07 12:06 ` [PATCH 06/12] swiotlb-xen: limit " Jan Beulich
2021-09-08 7:00 ` Christoph Hellwig
2021-09-10 23:23 ` Stefano Stabellini
2021-09-07 12:06 ` [PATCH 07/12] swiotlb-xen: drop leftover __ref Jan Beulich
2021-09-08 7:02 ` Christoph Hellwig
2021-09-10 23:24 ` Stefano Stabellini
2021-09-07 12:07 ` [PATCH 08/12] swiotlb-xen: arrange to have buffer info logged Jan Beulich
2021-09-08 7:04 ` Christoph Hellwig
2021-09-10 23:26 ` Stefano Stabellini
2021-09-07 12:07 ` [PATCH 09/12] swiotlb-xen: drop DEFAULT_NSLABS Jan Beulich
2021-09-08 7:06 ` Christoph Hellwig
2021-09-10 23:27 ` Stefano Stabellini
2021-09-07 12:11 ` [PATCH 11/12] xen/pci-swiotlb: reduce visibility of symbols Jan Beulich
2021-09-08 7:08 ` Christoph Hellwig
2021-09-07 12:13 ` [PATCH 12/12] swiotlb-xen: this is PV-only on x86 Jan Beulich
2021-09-08 7:14 ` Christoph Hellwig
2021-09-10 23:48 ` Stefano Stabellini
2021-09-13 7:28 ` Jan Beulich
2021-09-13 20:54 ` Stefano Stabellini
2021-09-13 7:51 ` Jan Beulich
2021-09-13 20:49 ` Stefano Stabellini
2021-09-08 15:18 ` [PATCH 00/12] swiotlb-xen: fixes and adjustments Juergen Gross
2021-09-14 8:30 ` Juergen Gross
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