2/6: numtasks_tasksupport Adds task management support by defining a function to be called from fork() to see if the resource group is within its share allocation Sets interface to be called from core when a task is moved to a resource group. --
Signed-Off-By: Chandra Seetharaman <[EMAIL PROTECTED]> include/linux/numtasks.h | 28 +++++++++++ kernel/fork.c | 7 ++ kernel/res_group/numtasks.c | 104 +++++++++++++++++++++++++++++++++++++++++++- 3 files changed, 137 insertions(+), 2 deletions(-) Index: linux-2617-rc3/include/linux/numtasks.h =================================================================== --- /dev/null 1970-01-01 00:00:00.000000000 +0000 +++ linux-2617-rc3/include/linux/numtasks.h 2006-04-27 10:18:50.000000000 -0700 @@ -0,0 +1,28 @@ +/* numtasks.h - No. of tasks resource controller for Resource Groups + * + * Copyright (C) Chandra Seetharaman, IBM Corp. 2003, 2004, 2005 + * + * Provides No. of tasks resource controller for Resource Groups + * + * 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. + * + */ +#ifndef _LINUX_NUMTASKS_H +#define _LINUX_NUMTASKS_H + +#ifdef CONFIG_RES_GROUPS_NUMTASKS +#include <linux/res_group_rc.h> + +extern int numtasks_allow_fork(struct resource_group *); + +#else /* CONFIG_RES_GROUPS_NUMTASKS */ + +#define numtasks_allow_fork(rgroup) (0) + +#endif /* CONFIG_RES_GROUPS_NUMTASKS */ +#endif /* _LINUX_NUMTASKS_H */ Index: linux-2617-rc3/kernel/res_group/numtasks.c =================================================================== --- linux-2617-rc3.orig/kernel/res_group/numtasks.c 2006-04-27 10:18:49.000000000 -0700 +++ linux-2617-rc3/kernel/res_group/numtasks.c 2006-04-27 10:18:50.000000000 -0700 @@ -21,7 +21,19 @@ static const char res_ctlr_name[] = "numtasks"; struct numtasks { + struct resource_group *rgroup;/* resource group i am part of... */ struct res_shares shares; + int cnt_min_shares; /* num_tasks min_shares in local units */ + int cnt_unused; /* has to borrow if more than this is needed */ + int cnt_max_shares; /* no tasks over this limit. */ + /* Three above cnt_* fields are protected + * by resource group's group_lock */ + atomic_t cnt_cur_alloc; /* current alloc from self */ + atomic_t cnt_borrowed; /* borrowed from the parent */ + + /* stats */ + int successes; + int failures; }; struct res_controller numtasks_ctlr; @@ -33,6 +45,84 @@ static struct numtasks *get_shares_numta return NULL; } +static struct numtasks *get_numtasks(struct resource_group *rgroup) +{ + return get_shares_numtasks(get_controller_shares(rgroup, + &numtasks_ctlr)); +} + +int numtasks_allow_fork(struct resource_group *rgroup) +{ + struct numtasks *res; + + /* controller is not registered; no resource group is given */ + if ((numtasks_ctlr.ctlr_id == NO_RES_ID) || (rgroup == NULL)) + return 0; + res = get_numtasks(rgroup); + + /* numtasks not available for this resource group */ + if (!res) + return 0; + + if (res->cnt_max_shares == SHARE_DONT_CARE) + return 0; + + /* Over the limit ? */ + if (atomic_read(&res->cnt_cur_alloc) >= res->cnt_max_shares) { + res->failures++; + return -ENOSPC; + } + + return 0; +} + +static void inc_usage_count(struct numtasks *res) +{ + atomic_inc(&res->cnt_cur_alloc); + + if (is_res_group_root(res->rgroup)) { + res->successes++; + return; + } + /* Do we need to borrow from our parent ? */ + if ((res->cnt_unused == SHARE_DONT_CARE) || + (atomic_read(&res->cnt_cur_alloc) > res->cnt_unused)) { + inc_usage_count(get_numtasks(res->rgroup->parent)); + atomic_inc(&res->cnt_borrowed); + } else + res->successes++; +} + +static void dec_usage_count(struct numtasks *res) +{ + if (atomic_read(&res->cnt_cur_alloc) == 0) + return; + atomic_dec(&res->cnt_cur_alloc); + if (atomic_read(&res->cnt_borrowed) > 0) { + atomic_dec(&res->cnt_borrowed); + dec_usage_count(get_numtasks(res->rgroup->parent)); + } +} + +static void numtasks_move_task(struct task_struct *task, + struct res_shares *old, struct res_shares *new) +{ + struct numtasks *oldres, *newres; + + if (old == new) + return; + + /* Decrement usage count of old resource group */ + oldres = get_shares_numtasks(old); + if (oldres) + dec_usage_count(oldres); + + /* Increment usage count of new resource group */ + newres = get_shares_numtasks(new); + if (newres) + inc_usage_count(newres); +} + /* Initialize share struct values */ static void numtasks_res_init_one(struct numtasks *numtasks_res) { @@ -50,6 +140,7 @@ static struct res_shares *numtasks_alloc res = kzalloc(sizeof(struct numtasks), GFP_KERNEL); if (!res) return NULL; + res->rgroup = rgroup; numtasks_res_init_one(res); return &res->shares; } @@ -60,7 +151,17 @@ static struct res_shares *numtasks_alloc */ static void numtasks_free_shares_struct(struct res_shares *my_res) { - kfree(get_shares_numtasks(my_res)); + struct numtasks *res, *parres; + int i, borrowed; + + res = get_shares_numtasks(my_res); + if (!is_res_group_root(res->rgroup)) { + parres = get_numtasks(res->rgroup->parent); + borrowed = atomic_read(&res->cnt_borrowed); + for (i = 0; i < borrowed; i++) + dec_usage_count(parres); + } + kfree(res); } struct res_controller numtasks_ctlr = { @@ -69,6 +170,7 @@ struct res_controller numtasks_ctlr = { .ctlr_id = NO_RES_ID, .alloc_shares_struct = numtasks_alloc_shares_struct, .free_shares_struct = numtasks_free_shares_struct, + .move_task = numtasks_move_task, }; int __init init_numtasks_res(void) Index: linux-2617-rc3/kernel/fork.c =================================================================== --- linux-2617-rc3.orig/kernel/fork.c 2006-04-27 10:14:38.000000000 -0700 +++ linux-2617-rc3/kernel/fork.c 2006-04-27 10:18:50.000000000 -0700 @@ -45,6 +45,7 @@ #include <linux/acct.h> #include <linux/cn_proc.h> #include <linux/res_group.h> +#include <linux/numtasks.h> #include <asm/pgtable.h> #include <asm/pgalloc.h> @@ -1311,7 +1312,7 @@ long do_fork(unsigned long clone_flags, int __user *child_tidptr) { struct task_struct *p; - int trace = 0; + int trace = 0, rc; struct pid *pid = alloc_pid(); long nr; @@ -1324,6 +1325,10 @@ long do_fork(unsigned long clone_flags, clone_flags |= CLONE_PTRACE; } + rc = numtasks_allow_fork(current->res_group); + if (rc) + return rc; + p = copy_process(clone_flags, stack_start, regs, stack_size, parent_tidptr, child_tidptr, nr); /* * Do this prior waking up the new thread - the thread pointer -- ---------------------------------------------------------------------- Chandra Seetharaman | Be careful what you choose.... - [EMAIL PROTECTED] | .......you may get it. ---------------------------------------------------------------------- ------------------------------------------------------- Using Tomcat but need to do more? Need to support web services, security? Get stuff done quickly with pre-integrated technology to make your job easier Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 _______________________________________________ ckrm-tech mailing list https://lists.sourceforge.net/lists/listinfo/ckrm-tech
