From: Christoph Hellwig <hch@infradead.org>
To: Chuck Lever <chuck.lever@oracle.com>
Cc: Christoph Hellwig <hch@infradead.org>,
Anna Schumaker <anna.schumaker@netapp.com>,
linux-rdma@vger.kernel.org,
Linux NFS Mailing List <linux-nfs@vger.kernel.org>
Subject: Re: [PATCH v3 03/24] xprtrdma: Remove support for FMR memory registration
Date: Tue, 11 Dec 2018 23:18:23 -0800 [thread overview]
Message-ID: <20181212071823.GA23247@infradead.org> (raw)
In-Reply-To: <F6E2B610-D386-45AC-B93B-906B61E22542@oracle.com>
On Tue, Dec 11, 2018 at 10:29:10AM -0500, Chuck Lever wrote:
>
>
> > On Dec 11, 2018, at 9:02 AM, Christoph Hellwig <hch@infradead.org> wrote:
> >
> > Can we also kill off rpcrdma_memreg_ops now? Indirect calls are
> > suprisingly expensive, especially in our post-spectre world, and
> > xprtrdma always seemed a little odd with this supper generic
> > abstraction.
>
> Yep, I'm considering replacing those indirect calls.
>
> However, note that the RPC layer is full of them too, as is the
> DMA operations that are used by xprtrdma. I'm not sure it will make
> much of a difference.
I've posted a series to remove them for the DMA fast path, and every
indirect calls adds additional cost.
next prev parent reply other threads:[~2018-12-12 7:18 UTC|newest]
Thread overview: 37+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-12-10 16:29 [PATCH v3 00/24] NFS/RDMA client for next Chuck Lever
2018-12-10 16:29 ` [PATCH v3 01/24] xprtrdma: Prevent leak of rpcrdma_rep objects Chuck Lever
2018-12-10 16:29 ` [PATCH v3 02/24] IB/rxe: IB_WR_REG_MR does not capture MR's iova field Chuck Lever
2018-12-11 14:00 ` Christoph Hellwig
2018-12-11 15:26 ` Chuck Lever
2018-12-10 16:29 ` [PATCH v3 03/24] xprtrdma: Remove support for FMR memory registration Chuck Lever
2018-12-11 14:02 ` Christoph Hellwig
2018-12-11 15:29 ` Chuck Lever
2018-12-12 7:18 ` Christoph Hellwig [this message]
2018-12-10 16:29 ` [PATCH v3 04/24] xprtrdma: Fix ri_max_segs and the result of ro_maxpages Chuck Lever
2018-12-10 16:29 ` [PATCH v3 05/24] xprtrdma: Reduce max_frwr_depth Chuck Lever
2018-12-11 14:02 ` Christoph Hellwig
2018-12-11 15:30 ` Chuck Lever
2018-12-12 7:18 ` Christoph Hellwig
2018-12-10 16:29 ` [PATCH v3 06/24] xprtrdma: Plant XID in on-the-wire RDMA offset (FRWR) Chuck Lever
2018-12-10 16:29 ` [PATCH v3 07/24] xprtrdma: Recognize XDRBUF_SPARSE_PAGES Chuck Lever
2018-12-10 16:30 ` [PATCH v3 08/24] xprtrdma: Remove request_module from backchannel Chuck Lever
2018-12-10 16:30 ` [PATCH v3 09/24] xprtrdma: Expose transport header errors Chuck Lever
2018-12-10 16:30 ` [PATCH v3 10/24] xprtrdma: Simplify locking that protects the rl_allreqs list Chuck Lever
2018-12-10 16:30 ` [PATCH v3 11/24] xprtrdma: Cull dprintk() call sites Chuck Lever
2018-12-10 16:30 ` [PATCH v3 12/24] xprtrdma: Clean up of xprtrdma chunk trace points Chuck Lever
2018-12-10 16:30 ` [PATCH v3 13/24] xprtrdma: Relocate the xprtrdma_mr_map " Chuck Lever
2018-12-10 16:30 ` [PATCH v3 14/24] xprtrdma: Add trace points for calls to transport switch methods Chuck Lever
2018-12-10 16:30 ` [PATCH v3 15/24] NFS: Make "port=" mount option optional for RDMA mounts Chuck Lever
2018-12-10 16:30 ` [PATCH v3 16/24] SUNRPC: Remove support for kerberos_v1 Chuck Lever
2018-12-12 21:20 ` Chuck Lever
2018-12-14 21:16 ` Chuck Lever
2018-12-10 16:30 ` [PATCH v3 17/24] SUNRPC: Fix some kernel doc complaints Chuck Lever
2018-12-10 16:30 ` [PATCH v3 18/24] NFS: Fix NFSv4 symbolic trace point output Chuck Lever
[not found] ` <632f5635-4c37-16ae-cdd0-65679d21c9ec@oracle.com>
2018-12-11 19:19 ` Calum Mackay
2018-12-10 16:31 ` [PATCH v3 19/24] SUNRPC: Simplify defining common RPC trace events Chuck Lever
2018-12-10 16:31 ` [PATCH v3 20/24] xprtrdma: Trace mapping, alloc, and dereg failures Chuck Lever
2018-12-10 16:31 ` [PATCH v3 21/24] xprtrdma: Update comments in frwr_op_send Chuck Lever
2018-12-10 16:31 ` [PATCH v3 22/24] xprtrdma: Replace outdated comment for rpcrdma_ep_post Chuck Lever
2018-12-10 16:31 ` [PATCH v3 23/24] xprtrdma: Add documenting comment for rpcrdma_buffer_destroy Chuck Lever
2018-12-10 16:31 ` [PATCH v3 24/24] xprtrdma: Clarify comments in rpcrdma_ia_remove Chuck Lever
2018-12-10 17:55 ` [PATCH v3 00/24] NFS/RDMA client for next Jason Gunthorpe
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