Unverified Commit 314ee703 authored by Max Kellermann's avatar Max Kellermann Committed by Christian Brauner
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fs/netfs: reorder struct fields to eliminate holes 



This shrinks `struct netfs_io_stream` from 104 to 96 bytes and `struct
netfs_io_request` from 600 to 576 bytes.

[DH: Modified as the patch to turn netfs_io_request::error into a short
was removed from the set]

Signed-off-by: default avatarMax Kellermann <max.kellermann@ionos.com>
Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/20250519134813.2975312-7-dhowells@redhat.com


cc: Paulo Alcantara <pc@manguebit.com>
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
parent d46a7b21

include/linux/netfs.h

+10 −10
Original line number Diff line number Diff line
@@ -144,8 +144,8 @@ struct netfs_io_stream { 
	struct netfs_io_subrequest *front;	/* Op being collected */

	unsigned long long	collected_to;	/* Position we've collected results to */

	size_t			transferred;	/* The amount transferred from this stream */

	enum netfs_io_source	source;		/* Where to read from/write to */

	unsigned short		error;		/* Aggregate error for the stream */

	enum netfs_io_source	source;		/* Where to read from/write to */

	unsigned char		stream_nr;	/* Index of stream in parent table */

	bool			avail;		/* T if stream is available */

	bool			active;		/* T if stream is active */
@@ -240,19 +240,10 @@ struct netfs_io_request { 
	void			*netfs_priv;	/* Private data for the netfs */

	void			*netfs_priv2;	/* Private data for the netfs */

	struct bio_vec		*direct_bv;	/* DIO buffer list (when handling iovec-iter) */

	unsigned int		direct_bv_count; /* Number of elements in direct_bv[] */

	unsigned int		debug_id;

	unsigned int		rsize;		/* Maximum read size (0 for none) */

	unsigned int		wsize;		/* Maximum write size (0 for none) */

	atomic_t		subreq_counter;	/* Next subreq->debug_index */

	unsigned int		nr_group_rel;	/* Number of refs to release on ->group */

	spinlock_t		lock;		/* Lock for queuing subreqs */

	unsigned long long	submitted;	/* Amount submitted for I/O so far */

	unsigned long long	len;		/* Length of the request */

	size_t			transferred;	/* Amount to be indicated as transferred */

	long			error;		/* 0 or error that occurred */

	enum netfs_io_origin	origin;		/* Origin of the request */

	bool			direct_bv_unpin; /* T if direct_bv[] must be unpinned */

	unsigned long long	i_size;		/* Size of the file */

	unsigned long long	start;		/* Start position */

	atomic64_t		issued_to;	/* Write issuer folio cursor */
@@ -260,7 +251,16 @@ struct netfs_io_request { 
	unsigned long long	cleaned_to;	/* Position we've cleaned folios to */

	unsigned long long	abandon_to;	/* Position to abandon folios to */

	pgoff_t			no_unlock_folio; /* Don't unlock this folio after read */

	unsigned int		direct_bv_count; /* Number of elements in direct_bv[] */

	unsigned int		debug_id;

	unsigned int		rsize;		/* Maximum read size (0 for none) */

	unsigned int		wsize;		/* Maximum write size (0 for none) */

	atomic_t		subreq_counter;	/* Next subreq->debug_index */

	unsigned int		nr_group_rel;	/* Number of refs to release on ->group */

	spinlock_t		lock;		/* Lock for queuing subreqs */

	unsigned char		front_folio_order; /* Order (size) of front folio */

	enum netfs_io_origin	origin;		/* Origin of the request */

	bool			direct_bv_unpin; /* T if direct_bv[] must be unpinned */

	refcount_t		ref;

	unsigned long		flags;

#define NETFS_RREQ_OFFLOAD_COLLECTION	0	/* Offload collection to workqueue */