b035c88c6a
dst->ports is accessed most notably by dsa_master_find_slave(), which is
invoked in the RX path.
dst->lags is accessed by dsa_lag_dev(), which is invoked in the RX path
of tag_dsa.c.
dst->tag_ops, dst->default_proto and dst->pd don't need to be in the
first cache line, so they are moved out by this change.
Before:
pahole -C dsa_switch_tree net/dsa/slave.o
struct dsa_switch_tree {
struct list_head list; /* 0 16 */
struct raw_notifier_head nh; /* 16 8 */
unsigned int index; /* 24 4 */
struct kref refcount; /* 28 4 */
bool setup; /* 32 1 */
/* XXX 7 bytes hole, try to pack */
const struct dsa_device_ops * tag_ops; /* 40 8 */
enum dsa_tag_protocol default_proto; /* 48 4 */
/* XXX 4 bytes hole, try to pack */
struct dsa_platform_data * pd; /* 56 8 */
/* --- cacheline 1 boundary (64 bytes) --- */
struct list_head ports; /* 64 16 */
struct list_head rtable; /* 80 16 */
struct net_device * * lags; /* 96 8 */
unsigned int lags_len; /* 104 4 */
unsigned int last_switch; /* 108 4 */
/* size: 112, cachelines: 2, members: 13 */
/* sum members: 101, holes: 2, sum holes: 11 */
/* last cacheline: 48 bytes */
};
After:
pahole -C dsa_switch_tree net/dsa/slave.o
struct dsa_switch_tree {
struct list_head list; /* 0 16 */
struct list_head ports; /* 16 16 */
struct raw_notifier_head nh; /* 32 8 */
unsigned int index; /* 40 4 */
struct kref refcount; /* 44 4 */
struct net_device * * lags; /* 48 8 */
bool setup; /* 56 1 */
/* XXX 7 bytes hole, try to pack */
/* --- cacheline 1 boundary (64 bytes) --- */
const struct dsa_device_ops * tag_ops; /* 64 8 */
enum dsa_tag_protocol default_proto; /* 72 4 */
/* XXX 4 bytes hole, try to pack */
struct dsa_platform_data * pd; /* 80 8 */
struct list_head rtable; /* 88 16 */
unsigned int lags_len; /* 104 4 */
unsigned int last_switch; /* 108 4 */
/* size: 112, cachelines: 2, members: 13 */
/* sum members: 101, holes: 2, sum holes: 11 */
/* last cacheline: 48 bytes */
};
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.