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Merged the rtems version of resource back to kern_resource and added method to resolve linker errors.

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This commit is contained in:
Jennifer Averett
2012-04-18 14:10:44 -05:00
parent 31230c0c72
commit a2ec3326e3
4 changed files with 14 additions and 176 deletions
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174
rtemsbsd/src/rtems-bsd-resource.c
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@@ -1,174 +0,0 @@
/**
* @file
*
* @ingroup rtems_bsd_rtems
*
* @brief TODO.
*/
/*
* Copyright (c) 2009, 2010 embedded brains GmbH. All rights reserved.
*
* embedded brains GmbH
* Obere Lagerstr. 30
* 82178 Puchheim
* Germany
* <rtems@embedded-brains.de>
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://www.rtems.com/license/LICENSE.
*/
#include <freebsd/machine/rtems-bsd-config.h>
#include <freebsd/sys/types.h>
#include <freebsd/sys/systm.h>
#include <freebsd/sys/lock.h>
#include <freebsd/sys/malloc.h>
#include <freebsd/sys/mutex.h>
#include <freebsd/sys/proc.h>
#include <freebsd/sys/resourcevar.h>
#include <freebsd/sys/rwlock.h>
#include <freebsd/sys/refcount.h>
static MALLOC_DEFINE(M_UIDINFO, "uidinfo", "uidinfo structures");
#define UIHASH(uid) (&uihashtbl[(uid) & uihash])
static struct rwlock uihashtbl_lock;
static LIST_HEAD(uihashhead, uidinfo) *uihashtbl;
static u_long uihash; /* size of hash table - 1 */
/*
* Find the uidinfo structure for a uid. This structure is used to
* track the total resource consumption (process count, socket buffer
* size, etc.) for the uid and impose limits.
*/
void
uihashinit()
{
uihashtbl = hashinit(maxproc / 16, M_UIDINFO, &uihash);
rw_init(&uihashtbl_lock, "uidinfo hash");
}
/*
* Look up a uidinfo struct for the parameter uid.
* uihashtbl_lock must be locked.
*/
static struct uidinfo *
uilookup(uid)
uid_t uid;
{
struct uihashhead *uipp;
struct uidinfo *uip;
rw_assert(&uihashtbl_lock, RA_LOCKED);
uipp = UIHASH(uid);
LIST_FOREACH(uip, uipp, ui_hash)
if (uip->ui_uid == uid)
break;
return (uip);
}
/*
* Find or allocate a struct uidinfo for a particular uid.
* Increase refcount on uidinfo struct returned.
* uifree() should be called on a struct uidinfo when released.
*/
struct uidinfo *
uifind(uid)
uid_t uid;
{
struct uidinfo *old_uip, *uip;
rw_rlock(&uihashtbl_lock);
uip = uilookup(uid);
if (uip == NULL) {
rw_runlock(&uihashtbl_lock);
uip = malloc(sizeof(*uip), M_UIDINFO, M_WAITOK | M_ZERO);
rw_wlock(&uihashtbl_lock);
/*
* There's a chance someone created our uidinfo while we
* were in malloc and not holding the lock, so we have to
* make sure we don't insert a duplicate uidinfo.
*/
if ((old_uip = uilookup(uid)) != NULL) {
/* Someone else beat us to it. */
free(uip, M_UIDINFO);
uip = old_uip;
} else {
refcount_init(&uip->ui_ref, 0);
uip->ui_uid = uid;
mtx_init(&uip->ui_vmsize_mtx, "ui_vmsize", NULL,
MTX_DEF);
LIST_INSERT_HEAD(UIHASH(uid), uip, ui_hash);
}
}
uihold(uip);
rw_unlock(&uihashtbl_lock);
return (uip);
}
/*
* Place another refcount on a uidinfo struct.
*/
void
uihold(uip)
struct uidinfo *uip;
{
refcount_acquire(&uip->ui_ref);
}
/*-
* Since uidinfo structs have a long lifetime, we use an
* opportunistic refcounting scheme to avoid locking the lookup hash
* for each release.
*
* If the refcount hits 0, we need to free the structure,
* which means we need to lock the hash.
* Optimal case:
* After locking the struct and lowering the refcount, if we find
* that we don't need to free, simply unlock and return.
* Suboptimal case:
* If refcount lowering results in need to free, bump the count
* back up, lose the lock and acquire the locks in the proper
* order to try again.
*/
void
uifree(uip)
struct uidinfo *uip;
{
int old;
/* Prepare for optimal case. */
old = uip->ui_ref;
if (old > 1 && atomic_cmpset_int(&uip->ui_ref, old, old - 1))
return;
/* Prepare for suboptimal case. */
rw_wlock(&uihashtbl_lock);
if (refcount_release(&uip->ui_ref)) {
LIST_REMOVE(uip, ui_hash);
rw_wunlock(&uihashtbl_lock);
if (uip->ui_sbsize != 0)
printf("freeing uidinfo: uid = %d, sbsize = %ld\n",
uip->ui_uid, uip->ui_sbsize);
if (uip->ui_proccnt != 0)
printf("freeing uidinfo: uid = %d, proccnt = %ld\n",
uip->ui_uid, uip->ui_proccnt);
if (uip->ui_vmsize != 0)
printf("freeing uidinfo: uid = %d, swapuse = %lld\n",
uip->ui_uid, (unsigned long long)uip->ui_vmsize);
mtx_destroy(&uip->ui_vmsize_mtx);
free(uip, M_UIDINFO);
return;
}
/*
* Someone added a reference between atomic_cmpset_int() and
* rw_wlock(&uihashtbl_lock).
*/
rw_wunlock(&uihashtbl_lock);
}