Bob Beers wrote:
> one small question ...
>
> On Tue, Oct 21, 2008 at 6:11 AM, Alan Jenkins
> <alan-jenkins@xxxxxxxxxxxxxx> wrote:
>
>> Allocate udev_device->envp lazily
>>
>> It's a pity to allocate 128 words when we don't need them.
>> Measured 2% _user_ cpu time reduction on EeePC coldplug.
>>
>> Signed-off-by: Alan Jenkins <alan-jenkins@xxxxxxxxxxxxxx>
>>
>> diff --git a/udev/lib/libudev-device.c b/udev/lib/libudev-device.c
>> index b54c727..69ab1f7 100644
>> --- a/udev/lib/libudev-device.c
>> +++ b/udev/lib/libudev-device.c
>> @@ -31,6 +31,8 @@
>> #include "libudev.h"
>> #include "libudev-private.h"
>>
>> +#define ENVP_SIZE 128
>> +
>> struct udev_device {
>> int refcount;
>> struct udev *udev;
>> @@ -46,7 +48,7 @@ struct udev_device {
>> struct udev_list_node devlinks_list;
>> int devlinks_uptodate;
>> struct udev_list_node properties_list;
>> - char *envp[128];
>> + char **envp;
>> int envp_uptodate;
>> char *driver;
>> int driver_set;
>> @@ -611,8 +613,11 @@ void udev_device_unref(struct udev_device *udev_device)
>> free(udev_device->devpath_old);
>> free(udev_device->physdevpath);
>> udev_list_cleanup_entries(udev_device->udev, &udev_device->sysattr_list);
>> - for (i = 0; i < ARRAY_SIZE(udev_device->envp) && udev_device->envp[i] != NULL; i++)
>> - free(udev_device->envp[i]);
>> + if (udev_device->envp != NULL) {
>> + for (i = 0; i < ENVP_SIZE && udev_device->envp[i] != NULL; i++)
>> + free(udev_device->envp[i]);
>> + free(udev_device->envp);
>> + }
>> info(udev_device->udev, "udev_device: %p released\n", udev_device);
>> free(udev_device);
>> }
>> @@ -1014,14 +1019,18 @@ char **udev_device_get_properties_envp(struct udev_device *udev_device)
>> unsigned int i;
>> struct udev_list_entry *list_entry;
>>
>> - for (i = 0; i < ARRAY_SIZE(udev_device->envp) && udev_device->envp[i] != NULL; i++)
>> - free(udev_device->envp[i]);
>> + if (udev_device->envp) {
>> + for (i = 0; i < 128 && udev_device->envp[i] != NULL; i++)
>>
>
> should this 128 also be ENVP_SIZE?
>
Yes, sorry. I see Kay fixed it already though :)
Alan
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