xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

SUNRPC: Optimize xdr_reserve_space()

Browse Source 
[ Upstream commit 62ed448cc53b654036f7d7f3c99f299d79ad14c3 ]

Transitioning between encode buffers is quite infrequent. It happens
about 1 time in 400 calls to xdr_reserve_space(), measured on NFSD
with a typical build/test workload.

Force the compiler to remove that code from xdr_reserve_space(),
which is a hot path on both the server and the client. This change
reduces the size of xdr_reserve_space() from 10 cache lines to 2
when compiled with -Os.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: J. Bruce Fields <bfields@fieldses.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Chuck Lever
2022-06-07 16:47:58 -04:00
committed by Greg Kroah-Hartman
parent ada1757b25
commit 6943f1073a
2 changed files with 25 additions and 8 deletions
Download Patch File Download Diff File Expand all files Collapse all files

16
include/linux/sunrpc/xdr.h
View File

@@ -242,7 +242,7 @@ extern void xdr_init_encode(struct xdr_stream *xdr, struct xdr_buf *buf,
extern __be32 *xdr_reserve_space(struct xdr_stream *xdr, size_t nbytes); extern __be32 *xdr_reserve_space(struct xdr_stream *xdr, size_t nbytes);
extern int xdr_reserve_space_vec(struct xdr_stream *xdr, struct kvec *vec, extern int xdr_reserve_space_vec(struct xdr_stream *xdr, struct kvec *vec,
size_t nbytes); size_t nbytes);
extern void xdr_commit_encode(struct xdr_stream *xdr); extern void __xdr_commit_encode(struct xdr_stream *xdr);
extern void xdr_truncate_encode(struct xdr_stream *xdr, size_t len); extern void xdr_truncate_encode(struct xdr_stream *xdr, size_t len);
extern int xdr_restrict_buflen(struct xdr_stream *xdr, int newbuflen); extern int xdr_restrict_buflen(struct xdr_stream *xdr, int newbuflen);
extern void xdr_write_pages(struct xdr_stream *xdr, struct page **pages, extern void xdr_write_pages(struct xdr_stream *xdr, struct page **pages,
@@ -305,6 +305,20 @@ xdr_reset_scratch_buffer(struct xdr_stream *xdr)
xdr_set_scratch_buffer(xdr, NULL, 0); xdr_set_scratch_buffer(xdr, NULL, 0);
} }
/**
* xdr_commit_encode - Ensure all data is written to xdr->buf
* @xdr: pointer to xdr_stream
*
* Handle encoding across page boundaries by giving the caller a
* temporary location to write to, then later copying the data into
* place. __xdr_commit_encode() does that copying.
*/
static inline void xdr_commit_encode(struct xdr_stream *xdr)
{
if (unlikely(xdr->scratch.iov_len))
__xdr_commit_encode(xdr);
}
/** /**
* xdr_stream_remaining - Return the number of bytes remaining in the stream * xdr_stream_remaining - Return the number of bytes remaining in the stream
* @xdr: pointer to struct xdr_stream * @xdr: pointer to struct xdr_stream

17
net/sunrpc/xdr.c
View File

@@ -691,7 +691,7 @@ void xdr_init_encode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p,
EXPORT_SYMBOL_GPL(xdr_init_encode); EXPORT_SYMBOL_GPL(xdr_init_encode);
/** /**
* xdr_commit_encode - Ensure all data is written to buffer * __xdr_commit_encode - Ensure all data is written to buffer
* @xdr: pointer to xdr_stream * @xdr: pointer to xdr_stream
* *
* We handle encoding across page boundaries by giving the caller a * We handle encoding across page boundaries by giving the caller a
@@ -703,22 +703,25 @@ EXPORT_SYMBOL_GPL(xdr_init_encode);
* required at the end of encoding, or any other time when the xdr_buf * required at the end of encoding, or any other time when the xdr_buf
* data might be read. * data might be read.
*/ */
inline void xdr_commit_encode(struct xdr_stream *xdr) void __xdr_commit_encode(struct xdr_stream *xdr)
{ {
int shift = xdr->scratch.iov_len; int shift = xdr->scratch.iov_len;
void *page; void *page;
if (shift == 0)
return;
page = page_address(*xdr->page_ptr); page = page_address(*xdr->page_ptr);
memcpy(xdr->scratch.iov_base, page, shift); memcpy(xdr->scratch.iov_base, page, shift);
memmove(page, page + shift, (void *)xdr->p - page); memmove(page, page + shift, (void *)xdr->p - page);
xdr_reset_scratch_buffer(xdr); xdr_reset_scratch_buffer(xdr);
} }
EXPORT_SYMBOL_GPL(xdr_commit_encode); EXPORT_SYMBOL_GPL(__xdr_commit_encode);
static __be32 *xdr_get_next_encode_buffer(struct xdr_stream *xdr, /*
size_t nbytes) * The buffer space to be reserved crosses the boundary between
* xdr->buf->head and xdr->buf->pages, or between two pages
* in xdr->buf->pages.
*/
static noinline __be32 *xdr_get_next_encode_buffer(struct xdr_stream *xdr,
size_t nbytes)
{ {
__be32 *p; __be32 *p;
int space_left; int space_left;