IB/uverbs: Convert *cdev to cdev in struct ib_uverbs_device

Instead of storing a pointer to a cdev, embed the entire struct cdev.

This change allows us to use the container_of() macro in
ib_uverbs_open() in a future patch.

This change increases the size of struct ib_uverbs_device to 168 bytes
across 3 cachelines from 80 bytes in 2 cachelines.  However, we
rearrange the members so that everything fits into the first cacheline
except for the struct cdev. Finally, we don't touch the cdev in any
fastpaths, so this change shouldn't negatively affect performance.

Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
This commit is contained in:
Alexander Chiang 2010-02-02 19:07:49 +00:00 committed by Roland Dreier
parent 676ad58553
commit 055422ddbb
2 changed files with 14 additions and 16 deletions

View File

@ -41,6 +41,7 @@
#include <linux/idr.h>
#include <linux/mutex.h>
#include <linux/completion.h>
#include <linux/cdev.h>
#include <rdma/ib_verbs.h>
#include <rdma/ib_umem.h>
@ -69,12 +70,12 @@
struct ib_uverbs_device {
struct kref ref;
int num_comp_vectors;
struct completion comp;
int devnum;
struct cdev *cdev;
struct device *dev;
struct ib_device *ib_dev;
int num_comp_vectors;
int devnum;
struct cdev cdev;
};
struct ib_uverbs_event_file {

View File

@ -43,7 +43,6 @@
#include <linux/sched.h>
#include <linux/file.h>
#include <linux/mount.h>
#include <linux/cdev.h>
#include <asm/uaccess.h>
@ -761,17 +760,15 @@ static void ib_uverbs_add_one(struct ib_device *device)
uverbs_dev->ib_dev = device;
uverbs_dev->num_comp_vectors = device->num_comp_vectors;
uverbs_dev->cdev = cdev_alloc();
if (!uverbs_dev->cdev)
goto err;
uverbs_dev->cdev->owner = THIS_MODULE;
uverbs_dev->cdev->ops = device->mmap ? &uverbs_mmap_fops : &uverbs_fops;
kobject_set_name(&uverbs_dev->cdev->kobj, "uverbs%d", uverbs_dev->devnum);
if (cdev_add(uverbs_dev->cdev, IB_UVERBS_BASE_DEV + uverbs_dev->devnum, 1))
cdev_init(&uverbs_dev->cdev, NULL);
uverbs_dev->cdev.owner = THIS_MODULE;
uverbs_dev->cdev.ops = device->mmap ? &uverbs_mmap_fops : &uverbs_fops;
kobject_set_name(&uverbs_dev->cdev.kobj, "uverbs%d", uverbs_dev->devnum);
if (cdev_add(&uverbs_dev->cdev, IB_UVERBS_BASE_DEV + uverbs_dev->devnum, 1))
goto err_cdev;
uverbs_dev->dev = device_create(uverbs_class, device->dma_device,
uverbs_dev->cdev->dev, uverbs_dev,
uverbs_dev->cdev.dev, uverbs_dev,
"uverbs%d", uverbs_dev->devnum);
if (IS_ERR(uverbs_dev->dev))
goto err_cdev;
@ -790,10 +787,10 @@ static void ib_uverbs_add_one(struct ib_device *device)
return;
err_class:
device_destroy(uverbs_class, uverbs_dev->cdev->dev);
device_destroy(uverbs_class, uverbs_dev->cdev.dev);
err_cdev:
cdev_del(uverbs_dev->cdev);
cdev_del(&uverbs_dev->cdev);
clear_bit(uverbs_dev->devnum, dev_map);
err:
@ -811,8 +808,8 @@ static void ib_uverbs_remove_one(struct ib_device *device)
return;
dev_set_drvdata(uverbs_dev->dev, NULL);
device_destroy(uverbs_class, uverbs_dev->cdev->dev);
cdev_del(uverbs_dev->cdev);
device_destroy(uverbs_class, uverbs_dev->cdev.dev);
cdev_del(&uverbs_dev->cdev);
spin_lock(&map_lock);
dev_table[uverbs_dev->devnum] = NULL;