From: Chuck Lever <chuck.lever@oracle.com>
To: Christoph Hellwig <hch@infradead.org>
Cc: Linux NFS Mailing List <linux-nfs@vger.kernel.org>, simo@redhat.com
Subject: Re: [PATCH RFC 04/10] SUNRPC: Add common byte-swapped RPC header constants
Date: Mon, 4 Feb 2019 09:56:20 -0500 [thread overview]
Message-ID: <7532348A-4059-4435-9D87-291902148681@oracle.com> (raw)
In-Reply-To: <20190204143239.GA15081@infradead.org>
> On Feb 4, 2019, at 9:32 AM, Christoph Hellwig <hch@infradead.org> wrote:
>
> On Mon, Feb 04, 2019 at 09:16:54AM -0500, Chuck Lever wrote:
>> They are. The problem is that we are byte-swapping the incoming wire
>> data and then comparing to CPU-endian constants in some hot paths.
>> It's better to leave the incoming data alone and compare to a pre-
>> byte-swapped constant. This patch adds some of these constants that
>> were missing, in preparation for fixing the hot paths.
>>
>> That is apparently not clear from the patch description, so I will
>> endeavor to improve it.
>
> Why do we need new enums / #defines for that?
>
> Just replace:
>
> if (beXX_to_cpu(pkt->field) == SOME_CONSTANT)
>
> with
>
> if (pkt->field == cpu_to_be32(SOME_CONSTANT))
>
> and we are done.
True.
> The latter is a pretty common pattern through the kernel.
However the pattern in the NFS server and lockd is to define a
lower-case version of the same macro that is pre-byte-swapped.
I'm attempting to follow existing precedent in this area.
We already have, for example, in various sunrpc headers:
enum rpc_accept_stat {
RPC_SUCCESS = 0,
RPC_PROG_UNAVAIL = 1,
RPC_PROG_MISMATCH = 2,
...
};
#define rpc_success cpu_to_be32(RPC_SUCCESS)
#define rpc_prog_unavail cpu_to_be32(RPC_PROG_UNAVAIL)
#define rpc_prog_mismatch cpu_to_be32(RPC_PROG_MISMATCH)
Or, for NFS:
enum nfs_stat {
...
NFSERR_SHARE_DENIED = 10015,
...
};
#define nfserr_share_denied cpu_to_be32(NFSERR_SHARE_DENIED)
There are some missing lower-case macros, which I am trying to
add to our existing collection before I rewrite the RPC header
encoding and decoding functions. So I'm adding:
+ rpc_gss_version = cpu_to_be32(RPC_GSS_VERSION),
+ rpc_call = cpu_to_be32(RPC_CALL),
+ rpc_reply = cpu_to_be32(RPC_REPLY),
+
+ rpc_msg_accepted = cpu_to_be32(RPC_MSG_ACCEPTED),
+ rpc_msg_denied = cpu_to_be32(RPC_MSG_DENIED),
Actually since we have decided not to use enum for these, this
smaller addition can simply be squashed into the later patches,
and I can drop this patch, which was intended as a clean-up but
now appears to be unnecessary.
--
Chuck Lever
next prev parent reply other threads:[~2019-02-04 14:56 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-02-01 19:57 [PATCH RFC 00/10] SUNRPC GSS overhaul Chuck Lever
2019-02-01 19:57 ` [PATCH RFC 01/10] SUNRPC: Remove some dprintk() call sites from auth functions Chuck Lever
2019-02-04 19:04 ` J. Bruce Fields
2019-02-04 19:07 ` Chuck Lever
2019-02-01 19:57 ` [PATCH RFC 02/10] SUNRPC: Remove rpc_xprt::tsh_size Chuck Lever
2019-02-01 19:57 ` [PATCH RFC 03/10] SUNRPC: Add build option to disable support for insecure enctypes Chuck Lever
2019-02-01 19:57 ` [PATCH RFC 04/10] SUNRPC: Add common byte-swapped RPC header constants Chuck Lever
2019-02-02 2:30 ` Tom Talpey
2019-02-02 22:46 ` Chuck Lever
2019-02-03 15:00 ` Trond Myklebust
2019-02-03 16:49 ` Chuck Lever
2019-02-03 18:58 ` Trond Myklebust
2019-02-02 17:02 ` Christoph Hellwig
2019-02-02 22:49 ` Chuck Lever
2019-02-04 7:53 ` Christoph Hellwig
2019-02-04 14:16 ` Chuck Lever
2019-02-04 14:32 ` Christoph Hellwig
2019-02-04 14:56 ` Chuck Lever [this message]
2019-02-04 19:37 ` J. Bruce Fields
2019-02-05 1:57 ` Tom Talpey
2019-02-01 19:57 ` [PATCH RFC 05/10] SUNRPC: Use struct xdr_stream when constructing RPC Call header Chuck Lever
2019-02-01 19:57 ` [PATCH RFC 06/10] SUNRPC: Clean up rpc_verify_header() Chuck Lever
2019-02-01 19:58 ` [PATCH RFC 07/10] SUNRPC: Use struct xdr_stream when decoding RPC Reply header Chuck Lever
2019-02-01 19:58 ` [PATCH RFC 08/10] SUNRPC: Introduce trace points in rpc_auth_gss.ko Chuck Lever
2019-02-01 19:58 ` [PATCH RFC 09/10] SUNRPC: Remove xdr_buf_trim() Chuck Lever
2019-02-04 19:46 ` J. Bruce Fields
2019-02-04 19:49 ` Chuck Lever
2019-02-04 20:00 ` Bruce Fields
2019-02-04 20:07 ` Chuck Lever
2019-02-04 20:11 ` Bruce Fields
2019-02-01 19:58 ` [PATCH RFC 10/10] SUNRPC: Add SPDX IDs to some net/sunrpc/auth_gss/ files Chuck Lever
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