+++ /dev/null
-/* ckrm_numtasks.c - "Number of tasks" resource controller for CKRM
- *
- * Copyright (C) Chandra Seetharaman, IBM Corp. 2003
- *
- * Latest version, more details at http://ckrm.sf.net
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- */
-
-/* Changes
- *
- * 31 Mar 2004: Created
- *
- */
-
-/*
- * Code Description: TBD
- */
-
-#include <linux/module.h>
-#include <linux/init.h>
-#include <linux/slab.h>
-#include <asm/errno.h>
-#include <linux/list.h>
-#include <linux/spinlock.h>
-#include <linux/ckrm.h>
-#include <linux/ckrm_rc.h>
-#include <linux/ckrm_tc.h>
-
-#define TOTAL_NUM_TASKS (131072) // 128 K
-#define NUMTASKS_DEBUG
-#define NUMTASKS_NAME "numtasks"
-
-typedef struct ckrm_numtasks {
- struct ckrm_core_class *core; // the core i am part of...
- struct ckrm_core_class *parent; // parent of the core above.
- struct ckrm_shares shares;
- spinlock_t cnt_lock; // always grab parent's lock first and then child's
- int cnt_guarantee; // num_tasks guarantee in local units
- int cnt_unused; // has to borrow if more than this is needed
- int cnt_limit; // no tasks over this limit.
- atomic_t cnt_cur_alloc; // current alloc from self
- atomic_t cnt_borrowed; // borrowed from the parent
-
- int over_guarantee; //turn on/off when cur_alloc goes over/under guarantee
-
- // internally maintained statictics to compare with max numbers
- int limit_failures; // no. of failures 'cause the request was over the limit
- int borrow_sucesses; // no. of successful borrows
- int borrow_failures; // no. of borrow faileures
-
- // Maximum the specific statictics has reached.
- int max_limit_failures;
- int max_borrow_sucesses;
- int max_borrow_failures;
-
- // Total number of specific statistics
- int tot_limit_failures;
- int tot_borrow_sucesses;
- int tot_borrow_failures;
-} ckrm_numtasks_t;
-
-struct ckrm_res_ctlr numtasks_rcbs;
-
-/* Initialize rescls values
- * May be called on each rcfs unmount or as part of error recovery
- * to make share values sane.
- * Does not traverse hierarchy reinitializing children.
- */
-static void
-numtasks_res_initcls_one(ckrm_numtasks_t *res)
-{
- res->shares.my_guarantee = CKRM_SHARE_DONTCARE;
- res->shares.my_limit = CKRM_SHARE_DONTCARE;
- res->shares.total_guarantee = CKRM_SHARE_DFLT_TOTAL_GUARANTEE;
- res->shares.max_limit = CKRM_SHARE_DFLT_MAX_LIMIT;
- res->shares.unused_guarantee = CKRM_SHARE_DFLT_TOTAL_GUARANTEE;
- res->shares.cur_max_limit = 0;
-
- res->cnt_guarantee = CKRM_SHARE_DONTCARE;
- res->cnt_unused = CKRM_SHARE_DONTCARE;
- res->cnt_limit = CKRM_SHARE_DONTCARE;
-
- res->over_guarantee = 0;
-
- res->limit_failures = 0;
- res->borrow_sucesses = 0;
- res->borrow_failures = 0;
-
- res->max_limit_failures = 0;
- res->max_borrow_sucesses = 0;
- res->max_borrow_failures = 0;
-
- res->tot_limit_failures = 0;
- res->tot_borrow_sucesses = 0;
- res->tot_borrow_failures = 0;
-
- atomic_set(&res->cnt_cur_alloc, 0);
- atomic_set(&res->cnt_borrowed, 0);
- return;
-}
-
-#if 0
-static void
-numtasks_res_initcls(void *my_res)
-{
- ckrm_numtasks_t *res = my_res;
-
- /* Write a version which propagates values all the way down
- and replace rcbs callback with that version */
-
-}
-#endif
-
-int
-numtasks_get_ref(void *arg, int force)
-{
- int rc, resid = numtasks_rcbs.resid;
- ckrm_numtasks_t *res;
- ckrm_core_class_t *core = arg;
-
- if ((resid < 0) || (core == NULL))
- return 1;
-
- res = ckrm_get_res_class(core, resid, ckrm_numtasks_t);
- if (res == NULL)
- return 1;
-
- atomic_inc(&res->cnt_cur_alloc);
-
- rc = 1;
- if (((res->parent) && (res->cnt_unused == CKRM_SHARE_DONTCARE)) ||
- (atomic_read(&res->cnt_cur_alloc) > res->cnt_unused)) {
-
- rc = 0;
- if (!force && (res->cnt_limit != CKRM_SHARE_DONTCARE) &&
- (atomic_read(&res->cnt_cur_alloc) > res->cnt_limit)) {
- res->limit_failures++;
- res->tot_limit_failures++;
- } else if (res->parent != NULL) {
- if ((rc = numtasks_get_ref(res->parent, force)) == 1) {
- atomic_inc(&res->cnt_borrowed);
- res->borrow_sucesses++;
- res->tot_borrow_sucesses++;
- res->over_guarantee = 1;
- } else {
- res->borrow_failures++;
- res->tot_borrow_failures++;
- }
- } else {
- rc = force;
- }
- } else if (res->over_guarantee) {
- res->over_guarantee = 0;
-
- if (res->max_limit_failures < res->limit_failures) {
- res->max_limit_failures = res->limit_failures;
- }
- if (res->max_borrow_sucesses < res->borrow_sucesses) {
- res->max_borrow_sucesses = res->borrow_sucesses;
- }
- if (res->max_borrow_failures < res->borrow_failures) {
- res->max_borrow_failures = res->borrow_failures;
- }
- res->limit_failures = 0;
- res->borrow_sucesses = 0;
- res->borrow_failures = 0;
- }
-
- if (!rc) {
- atomic_dec(&res->cnt_cur_alloc);
- }
- return rc;
-}
-
-void
-numtasks_put_ref(void *arg)
-{
- int resid = numtasks_rcbs.resid;
- ckrm_numtasks_t *res;
- ckrm_core_class_t *core = arg;
-
- if ((resid == -1) || (core == NULL)) {
- return;
- }
-
- res = ckrm_get_res_class(core, resid, ckrm_numtasks_t);
- if (res == NULL)
- return;
- atomic_dec(&res->cnt_cur_alloc);
- if (atomic_read(&res->cnt_borrowed) > 0) {
- atomic_dec(&res->cnt_borrowed);
- numtasks_put_ref(res->parent);
- }
- return;
-}
-
-static void *
-numtasks_res_alloc(struct ckrm_core_class *core, struct ckrm_core_class *parent)
-{
- ckrm_numtasks_t *res;
-
- res = kmalloc(sizeof(ckrm_numtasks_t), GFP_ATOMIC);
-
- if (res) {
- res->core = core;
- res->parent = parent;
- numtasks_res_initcls_one(res);
- res->cnt_lock = SPIN_LOCK_UNLOCKED;
- if (parent == NULL) {
- // I am part of root class. so set the max tasks to available
- // default
- res->cnt_guarantee = TOTAL_NUM_TASKS;
- res->cnt_unused = TOTAL_NUM_TASKS;
- res->cnt_limit = TOTAL_NUM_TASKS;
- }
- } else {
- printk(KERN_ERR "numtasks_res_alloc: failed GFP_ATOMIC alloc\n");
- }
- return res;
-}
-
-/*
- * No locking of this resource class object necessary as we are not
- * supposed to be assigned (or used) when/after this function is called.
- */
-static void
-numtasks_res_free(void *my_res)
-{
- ckrm_numtasks_t *res = my_res, *parres, *childres;
- ckrm_core_class_t *child = NULL;
- int i, borrowed, maxlimit, resid = numtasks_rcbs.resid;
-
- if (!res)
- return;
-
- // Assuming there will be no children when this function is called
-
- parres = ckrm_get_res_class(res->parent, resid, ckrm_numtasks_t);
-
- if (unlikely(atomic_read(&res->cnt_cur_alloc) != 0 ||
- atomic_read(&res->cnt_borrowed))) {
- printk(KERN_ERR "numtasks_res_free: resource still alloc'd %p\n", res);
- if ((borrowed = atomic_read(&res->cnt_borrowed)) > 0) {
- for (i = 0; i < borrowed; i++) {
- numtasks_put_ref(parres->core);
- }
- }
- }
-
- // return child's limit/guarantee to parent node
- spin_lock(&parres->cnt_lock);
- child_guarantee_changed(&parres->shares, res->shares.my_guarantee, 0);
-
- // run thru parent's children and get the new max_limit of the parent
- ckrm_lock_hier(parres->core);
- maxlimit = 0;
- while ((child = ckrm_get_next_child(parres->core, child)) != NULL) {
- childres = ckrm_get_res_class(child, resid, ckrm_numtasks_t);
- if (maxlimit < childres->shares.my_limit) {
- maxlimit = childres->shares.my_limit;
- }
- }
- ckrm_unlock_hier(parres->core);
- if (parres->shares.cur_max_limit < maxlimit) {
- parres->shares.cur_max_limit = maxlimit;
- }
-
- spin_unlock(&parres->cnt_lock);
- kfree(res);
- return;
-}
-/*
- * Recalculate the guarantee and limit in real units... and propagate the
- * same to children.
- * Caller is responsible for protecting res and for the integrity of parres
- */
-static void
-recalc_and_propagate(ckrm_numtasks_t *res, ckrm_numtasks_t *parres)
-{
- ckrm_core_class_t *child = NULL;
- ckrm_numtasks_t *childres;
- int resid = numtasks_rcbs.resid;
-
- if (parres) {
- struct ckrm_shares *par = &parres->shares;
- struct ckrm_shares *self = &res->shares;
-
- // calculate cnt_guarantee and cnt_limit
- //
- if (parres->cnt_guarantee == CKRM_SHARE_DONTCARE) {
- res->cnt_guarantee = CKRM_SHARE_DONTCARE;
- } else {
- res->cnt_guarantee = (self->my_guarantee * parres->cnt_guarantee)
- / par->total_guarantee;
- }
- if (parres->cnt_limit == CKRM_SHARE_DONTCARE) {
- res->cnt_limit = CKRM_SHARE_DONTCARE;
- } else {
- res->cnt_limit = (self->my_limit * parres->cnt_limit)
- / par->max_limit;
- }
-
- // Calculate unused units
- if (res->cnt_guarantee == CKRM_SHARE_DONTCARE) {
- res->cnt_unused = CKRM_SHARE_DONTCARE;
- } else {
- res->cnt_unused = (self->unused_guarantee *
- res->cnt_guarantee) / self->total_guarantee;
- }
- }
-
- // propagate to children
- ckrm_lock_hier(res->core);
- while ((child = ckrm_get_next_child(res->core, child)) != NULL) {
- childres = ckrm_get_res_class(child, resid, ckrm_numtasks_t);
-
- spin_lock(&childres->cnt_lock);
- recalc_and_propagate(childres, res);
- spin_unlock(&childres->cnt_lock);
- }
- ckrm_unlock_hier(res->core);
- return;
-}
-
-static int
-numtasks_set_share_values(void *my_res, struct ckrm_shares *new)
-{
- ckrm_numtasks_t *parres, *res = my_res;
- struct ckrm_shares *cur = &res->shares, *par;
- int rc = -EINVAL, resid = numtasks_rcbs.resid;
-
- if (!res)
- return rc;
-
- if (res->parent) {
- parres = ckrm_get_res_class(res->parent, resid, ckrm_numtasks_t);
- spin_lock(&parres->cnt_lock);
- spin_lock(&res->cnt_lock);
- par = &parres->shares;
- } else {
- spin_lock(&res->cnt_lock);
- par = NULL;
- parres = NULL;
- }
-
- rc = set_shares(new, cur, par);
-
- if ((rc == 0) && parres) {
- // Calculate parent's unused units
- if (parres->cnt_guarantee == CKRM_SHARE_DONTCARE) {
- parres->cnt_unused = CKRM_SHARE_DONTCARE;
- } else {
- parres->cnt_unused = (par->unused_guarantee *
- parres->cnt_guarantee) / par->total_guarantee;
- }
-
- recalc_and_propagate(res, parres);
- }
- spin_unlock(&res->cnt_lock);
- if (res->parent) {
- spin_unlock(&parres->cnt_lock);
- }
- return rc;
-}
-
-
-static int
-numtasks_get_share_values(void *my_res, struct ckrm_shares *shares)
-{
- ckrm_numtasks_t *res = my_res;
-
- if (!res)
- return -EINVAL;
- *shares = res->shares;
- return 0;
-}
-
-static int
-numtasks_get_stats(void *my_res, struct seq_file *sfile)
-{
- ckrm_numtasks_t *res = my_res;
-
- if (!res)
- return -EINVAL;
-
- seq_printf(sfile, "Number of tasks resource:\n");
- seq_printf(sfile, "Total Over limit failures: %d\n",
- res->tot_limit_failures);
- seq_printf(sfile, "Total Over guarantee sucesses: %d\n",
- res->tot_borrow_sucesses);
- seq_printf(sfile, "Total Over guarantee failures: %d\n",
- res->tot_borrow_failures);
-
- seq_printf(sfile, "Maximum Over limit failures: %d\n",
- res->max_limit_failures);
- seq_printf(sfile, "Maximum Over guarantee sucesses: %d\n",
- res->max_borrow_sucesses);
- seq_printf(sfile, "Maximum Over guarantee failures: %d\n",
- res->max_borrow_failures);
-#ifdef NUMTASKS_DEBUG
- seq_printf(sfile, "cur_alloc %d; borrowed %d; cnt_guar %d; cnt_limit %d "
- "unused_guarantee %d, cur_max_limit %d\n",
- atomic_read(&res->cnt_cur_alloc),
- atomic_read(&res->cnt_borrowed),
- res->cnt_guarantee,
- res->cnt_limit,
- res->shares.unused_guarantee,
- res->shares.cur_max_limit);
-#endif
-
- return 0;
-}
-
-static int
-numtasks_show_config(void *my_res, struct seq_file *sfile)
-{
- ckrm_numtasks_t *res = my_res;
-
- if (!res)
- return -EINVAL;
-
- seq_printf(sfile, "res=%s,parameter=somevalue\n",NUMTASKS_NAME);
- return 0;
-}
-
-static int
-numtasks_set_config(void *my_res, const char *cfgstr)
-{
- ckrm_numtasks_t *res = my_res;
-
- if (!res)
- return -EINVAL;
- printk("numtasks config='%s'\n",cfgstr);
- return 0;
-}
-
-static void
-numtasks_change_resclass(void *task, void *old, void *new)
-{
- ckrm_numtasks_t *oldres = old;
- ckrm_numtasks_t *newres = new;
-
- if (oldres != (void *) -1) {
- struct task_struct *tsk = task;
- if (!oldres) {
- struct ckrm_core_class *old_core = &(tsk->parent->taskclass->core);
- oldres = ckrm_get_res_class(old_core, numtasks_rcbs.resid,
- ckrm_numtasks_t);
- }
- numtasks_put_ref(oldres->core);
- }
- if (newres) {
- (void) numtasks_get_ref(newres->core, 1);
- }
-}
-
-struct ckrm_res_ctlr numtasks_rcbs = {
- .res_name = NUMTASKS_NAME,
- .res_hdepth = 1,
- .resid = -1,
- .res_alloc = numtasks_res_alloc,
- .res_free = numtasks_res_free,
- .set_share_values = numtasks_set_share_values,
- .get_share_values = numtasks_get_share_values,
- .get_stats = numtasks_get_stats,
- .show_config = numtasks_show_config,
- .set_config = numtasks_set_config,
- .change_resclass = numtasks_change_resclass,
-};
-
-int __init
-init_ckrm_numtasks_res(void)
-{
- struct ckrm_classtype *clstype;
- int resid = numtasks_rcbs.resid;
-
- clstype = ckrm_find_classtype_by_name("taskclass");
- if (clstype == NULL) {
- printk(KERN_INFO " Unknown ckrm classtype<taskclass>");
- return -ENOENT;
- }
-
- if (resid == -1) {
- resid = ckrm_register_res_ctlr(clstype,&numtasks_rcbs);
- printk("........init_ckrm_numtasks_res -> %d\n",resid);
- }
- return 0;
-}
-
-void __exit
-exit_ckrm_numtasks_res(void)
-{
- ckrm_unregister_res_ctlr(&numtasks_rcbs);
- numtasks_rcbs.resid = -1;
-}
-
-module_init(init_ckrm_numtasks_res)
-module_exit(exit_ckrm_numtasks_res)
-
-EXPORT_SYMBOL(numtasks_get_ref);
-EXPORT_SYMBOL(numtasks_put_ref);
-
-MODULE_LICENSE("GPL");
-
git://git.onelab.eu / linux-2.6.git / commitdiff