Commit 0a323dad authored by Pierre-Louis Bossart's avatar Pierre-Louis Bossart Committed by Vinod Koul
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soundwire: optimize sdw_bus structure 



The sdw_bus structure has seen multiple additions over the years. It's
one of the most used structures in this subsystem, so there's merit in
reshuffling the members a bit with 'pahole' to reduce holes and
structures across cache lines.

before:

struct sdw_bus {
	struct device *            dev;                  /*     0     8 */
	struct sdw_master_device * md;                   /*     8     8 */
	int                        controller_id;        /*    16     4 */
	unsigned int               link_id;              /*    20     4 */
	int                        id;                   /*    24     4 */

	/* XXX 4 bytes hole, try to pack */

	struct list_head           slaves;               /*    32    16 */
	long unsigned int          assigned[1];          /*    48     8 */
	struct mutex               bus_lock;             /*    56   160 */
	/* --- cacheline 3 boundary (192 bytes) was 24 bytes ago --- */
	struct lock_class_key      bus_lock_key;         /*   216    16 */
	struct mutex               msg_lock;             /*   232   160 */
	/* --- cacheline 6 boundary (384 bytes) was 8 bytes ago --- */
	struct lock_class_key      msg_lock_key;         /*   392    16 */
	int                        (*compute_params)(struct sdw_bus *); /*   408     8 */
	const struct sdw_master_ops  * ops;              /*   416     8 */
	const struct sdw_master_port_ops  * port_ops;    /*   424     8 */
	struct sdw_bus_params      params;               /*   432    36 */

	/* XXX 4 bytes hole, try to pack */

	/* --- cacheline 7 boundary (448 bytes) was 24 bytes ago --- */
	struct sdw_master_prop     prop;                 /*   472    72 */

	/* XXX last struct has 6 bytes of padding */

	/* --- cacheline 8 boundary (512 bytes) was 32 bytes ago --- */
	void *                     vendor_specific_prop; /*   544     8 */
	struct list_head           m_rt_list;            /*   552    16 */
	struct dentry *            debugfs;              /*   568     8 */
	/* --- cacheline 9 boundary (576 bytes) --- */
	struct irq_chip            irq_chip;             /*   576   264 */
	/* --- cacheline 13 boundary (832 bytes) was 8 bytes ago --- */
	struct irq_domain *        domain;               /*   840     8 */
	struct sdw_defer           defer_msg;            /*   848   112 */
	/* --- cacheline 15 boundary (960 bytes) --- */
	unsigned int               clk_stop_timeout;     /*   960     4 */
	u32                        bank_switch_timeout;  /*   964     4 */
	bool                       multi_link;           /*   968     1 */

	/* XXX 3 bytes hole, try to pack */

	int                        hw_sync_min_links;    /*   972     4 */
	int                        stream_refcount;      /*   976     4 */

	/* size: 984, cachelines: 16, members: 27 */
	/* sum members: 969, holes: 3, sum holes: 11 */
	/* padding: 4 */
	/* paddings: 1, sum paddings: 6 */
	/* last cacheline: 24 bytes */
};

after:

struct sdw_bus {
	struct device *            dev;                  /*     0     8 */
	struct sdw_master_device * md;                   /*     8     8 */
	struct lock_class_key      bus_lock_key;         /*    16    16 */
	struct mutex               bus_lock;             /*    32   160 */
	/* --- cacheline 3 boundary (192 bytes) --- */
	struct list_head           slaves;               /*   192    16 */
	struct lock_class_key      msg_lock_key;         /*   208    16 */
	struct mutex               msg_lock;             /*   224   160 */
	/* --- cacheline 6 boundary (384 bytes) --- */
	struct list_head           m_rt_list;            /*   384    16 */
	struct sdw_defer           defer_msg;            /*   400   112 */
	/* --- cacheline 8 boundary (512 bytes) --- */
	struct sdw_bus_params      params;               /*   512    36 */
	int                        stream_refcount;      /*   548     4 */
	const struct sdw_master_ops  * ops;              /*   552     8 */
	const struct sdw_master_port_ops  * port_ops;    /*   560     8 */
	struct sdw_master_prop     prop;                 /*   568    72 */

	/* XXX last struct has 6 bytes of padding */

	/* --- cacheline 10 boundary (640 bytes) --- */
	void *                     vendor_specific_prop; /*   640     8 */
	int                        hw_sync_min_links;    /*   648     4 */
	int                        controller_id;        /*   652     4 */
	unsigned int               link_id;              /*   656     4 */
	int                        id;                   /*   660     4 */
	int                        (*compute_params)(struct sdw_bus *); /*   664     8 */
	long unsigned int          assigned[1];          /*   672     8 */
	unsigned int               clk_stop_timeout;     /*   680     4 */
	u32                        bank_switch_timeout;  /*   684     4 */
	struct irq_chip            irq_chip;             /*   688   264 */
	/* --- cacheline 14 boundary (896 bytes) was 56 bytes ago --- */
	struct irq_domain *        domain;               /*   952     8 */
	/* --- cacheline 15 boundary (960 bytes) --- */
	struct dentry *            debugfs;              /*   960     8 */
	bool                       multi_link;           /*   968     1 */

	/* size: 976, cachelines: 16, members: 27 */
	/* padding: 7 */
	/* paddings: 1, sum paddings: 6 */
	/* last cacheline: 16 bytes */
};

Signed-off-by: default avatarPierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: default avatarBard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20241003070650.62787-5-yung-chuan.liao@linux.intel.com


Signed-off-by: default avatarVinod Koul <vkoul@kernel.org>
parent 6cb2c156

include/linux/soundwire/sdw.h

+40 −37
Original line number Diff line number Diff line
@@ -871,68 +871,71 @@ struct sdw_master_ops { 
 * struct sdw_bus - SoundWire bus

 * @dev: Shortcut to &bus->md->dev to avoid changing the entire code.

 * @md: Master device

 * @controller_id: system-unique controller ID. If set to -1, the bus @id will be used.

 * @link_id: Link id number, can be 0 to N, unique for each Controller

 * @id: bus system-wide unique id

 * @slaves: list of Slaves on this bus

 * @assigned: Bitmap for Slave device numbers.

 * Bit set implies used number, bit clear implies unused number.

 * @bus_lock_key: bus lock key associated to @bus_lock

 * @bus_lock: bus lock

 * @slaves: list of Slaves on this bus

 * @msg_lock_key: message lock key associated to @msg_lock

 * @msg_lock: message lock

 * @compute_params: points to Bus resource management implementation

 * @ops: Master callback ops

 * @port_ops: Master port callback ops

 * @params: Current bus parameters

 * @prop: Master properties

 * @vendor_specific_prop: pointer to non-standard properties

 * @m_rt_list: List of Master instance of all stream(s) running on Bus. This

 * is used to compute and program bus bandwidth, clock, frame shape,

 * transport and port parameters

 * @debugfs: Bus debugfs

 * @domain: IRQ domain

 * @defer_msg: Defer message

 * @clk_stop_timeout: Clock stop timeout computed

 * @bank_switch_timeout: Bank switch timeout computed

 * @multi_link: Store bus property that indicates if multi links

 * are supported. This flag is populated by drivers after reading

 * appropriate firmware (ACPI/DT).

 * @params: Current bus parameters

 * @stream_refcount: number of streams currently using this bus

 * @ops: Master callback ops

 * @port_ops: Master port callback ops

 * @prop: Master properties

 * @vendor_specific_prop: pointer to non-standard properties

 * @hw_sync_min_links: Number of links used by a stream above which

 * hardware-based synchronization is required. This value is only

 * meaningful if multi_link is set. If set to 1, hardware-based

 * synchronization will be used even if a stream only uses a single

 * SoundWire segment.

 * @stream_refcount: number of streams currently using this bus

 * @controller_id: system-unique controller ID. If set to -1, the bus @id will be used.

 * @link_id: Link id number, can be 0 to N, unique for each Controller

 * @id: bus system-wide unique id

 * @compute_params: points to Bus resource management implementation

 * @assigned: Bitmap for Slave device numbers.

 * Bit set implies used number, bit clear implies unused number.

 * @clk_stop_timeout: Clock stop timeout computed

 * @bank_switch_timeout: Bank switch timeout computed

 * @domain: IRQ domain

 * @irq_chip: IRQ chip

 * @debugfs: Bus debugfs (optional)

 * @multi_link: Store bus property that indicates if multi links

 * are supported. This flag is populated by drivers after reading

 * appropriate firmware (ACPI/DT).

 */

struct sdw_bus {

	struct device *dev;

	struct sdw_master_device *md;

	int controller_id;

	unsigned int link_id;

	int id;

	struct list_head slaves;

	DECLARE_BITMAP(assigned, SDW_MAX_DEVICES);

	struct mutex bus_lock;

	struct lock_class_key bus_lock_key;

	struct mutex msg_lock;

	struct mutex bus_lock;

	struct list_head slaves;

	struct lock_class_key msg_lock_key;

	int (*compute_params)(struct sdw_bus *bus);

	struct mutex msg_lock;

	struct list_head m_rt_list;

	struct sdw_defer defer_msg;

	struct sdw_bus_params params;

	int stream_refcount;

	const struct sdw_master_ops *ops;

	const struct sdw_master_port_ops *port_ops;

	struct sdw_bus_params params;

	struct sdw_master_prop prop;

	void *vendor_specific_prop;

	struct list_head m_rt_list;

	int hw_sync_min_links;

	int controller_id;

	unsigned int link_id;

	int id;

	int (*compute_params)(struct sdw_bus *bus);

	DECLARE_BITMAP(assigned, SDW_MAX_DEVICES);

	unsigned int clk_stop_timeout;

	u32 bank_switch_timeout;

	struct irq_chip irq_chip;

	struct irq_domain *domain;

#ifdef CONFIG_DEBUG_FS

	struct dentry *debugfs;

#endif

	struct irq_chip irq_chip;

	struct irq_domain *domain;

	struct sdw_defer defer_msg;

	unsigned int clk_stop_timeout;

	u32 bank_switch_timeout;

	bool multi_link;

	int hw_sync_min_links;

	int stream_refcount;

};



int sdw_bus_master_add(struct sdw_bus *bus, struct device *parent,