[patch 05/38] CKRM e18: Classtype definitions for task class

Gerrit Huizenga
2005-06-23T07:13:22Z

[-- Attachment #1: 05-diff_taskclass --]
[-- Type: text/plain, Size: 30118 bytes --]

This patch provides the extensions for CKRM to track task classes.
This is the base to enable task class based resource control for
cpu, memory and disk I/O.

Signed-Off-By: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-Off-By: Hubertus Franke <frankeh@us.ibm.com>
Signed-Off-By: Shailabh Nagar <nagar@us.ibm.com>
Signed-Off-By: Vivek Kashyap <vivk@us.ibm.com>
Signed-Off-By: Gerrit Huizenga <gh@us.ibm.com>
Signed-off-by: Nishanth Aravamudan <nacc@us.ibm.com>

fs/rcfs/Makefile | 1
fs/rcfs/rootdir.c | 12
fs/rcfs/tc_magic.c | 93 +++++
include/linux/ckrm_tc.h | 46 ++
include/linux/sched.h | 11
init/Kconfig | 12
kernel/ckrm/Makefile | 1
kernel/ckrm/ckrm_tc.c | 745 ++++++++++++++++++++++++++++++++++++++++++++++++
8 files changed, 915 insertions(+), 6 deletions(-)

Index: linux-2.6.12-ckrm1/fs/rcfs/Makefile
===================================================================
--- linux-2.6.12-ckrm1.orig/fs/rcfs/Makefile 2005-06-20 13:08:30.000000000 -0700
+++ linux-2.6.12-ckrm1/fs/rcfs/Makefile 2005-06-20 13:08:31.000000000 -0700
@@ -5,3 +5,4 @@
obj-$(CONFIG_RCFS_FS) += rcfs.o

rcfs-y := super.o inode.o dir.o rootdir.o magic.o
+rcfs-$(CONFIG_CKRM_TYPE_TASKCLASS) += tc_magic.o
Index: linux-2.6.12-ckrm1/fs/rcfs/rootdir.c
===================================================================
--- linux-2.6.12-ckrm1.orig/fs/rcfs/rootdir.c 2005-06-20 13:08:30.000000000 -0700
+++ linux-2.6.12-ckrm1/fs/rcfs/rootdir.c 2005-06-20 13:08:31.000000000 -0700
@@ -58,7 +58,7 @@ int rcfs_unregister_engine(struct rbce_e
return 0;
}

-EXPORT_SYMBOL(rcfs_unregister_engine);
+EXPORT_SYMBOL_GPL(rcfs_unregister_engine);

/*
* rcfs_mkroot
@@ -183,6 +183,10 @@ int rcfs_deregister_classtype(struct ckr

EXPORT_SYMBOL_GPL(rcfs_deregister_classtype);

+#ifdef CONFIG_CKRM_TYPE_TASKCLASS
+extern struct rcfs_mfdesc tc_mfdesc;
+#endif
+
/* Common root and magic file entries.
* root name, root permissions, magic file names and magic file permissions
* are needed by all entities (classtypes and classification engines) existing
@@ -193,6 +197,10 @@ EXPORT_SYMBOL_GPL(rcfs_deregister_classt
* table to initialize their magf entries.
*/

-struct rcfs_mfdesc *genmfdesc[] = {
+struct rcfs_mfdesc *genmfdesc[CKRM_MAX_CLASSTYPES] = {
+#ifdef CONFIG_CKRM_TYPE_TASKCLASS
+ &tc_mfdesc,
+#else
NULL,
+#endif
};
Index: linux-2.6.12-ckrm1/fs/rcfs/tc_magic.c
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ linux-2.6.12-ckrm1/fs/rcfs/tc_magic.c 2005-06-20 13:08:31.000000000 -0700
@@ -0,0 +1,93 @@
+/*
+ * fs/rcfs/tc_magic.c
+ *
+ * Copyright (C) Shailabh Nagar, IBM Corp. 2004
+ * (C) Vivek Kashyap, IBM Corp. 2004
+ * (C) Chandra Seetharaman, IBM Corp. 2004
+ * (C) Hubertus Franke, IBM Corp. 2004
+ *
+ * define magic fileops for taskclass classtype
+ *
+ * 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.
+ */
+
+#include <linux/rcfs.h>
+#include <linux/ckrm_tc.h>
+
+/*
+ * Taskclass general
+ *
+ * Define structures for taskclass root directory and its magic files
+ * In taskclasses, there is one set of magic files, created automatically under
+ * the taskclass root (upon classtype registration) and each directory (class)
+ * created subsequently. However, classtypes can also choose to have different
+ * sets of magic files created under their root and other directories under
+ * root using their mkdir function. RCFS only provides helper functions for
+ * creating the root directory and its magic files
+ *
+ */
+
+#define TC_FILE_MODE (S_IFREG | S_IRUGO | S_IWUSR)
+
+#define NR_TCROOTMF 7
+struct rcfs_magf tc_rootdesc[NR_TCROOTMF] = {
+ /* First entry must be root */
+ {
+ /* .name = should not be set, copy from classtype name */
+ .mode = RCFS_DEFAULT_DIR_MODE,
+ .i_op = &rcfs_dir_inode_operations,
+ .i_fop = &simple_dir_operations,
+ },
+ /* Rest are root's magic files */
+ {
+ .name = "target",
+ .mode = TC_FILE_MODE,
+ .i_fop = &target_fileops,
+ .i_op = &rcfs_file_inode_operations,
+ },
+ {
+ .name = "members",
+ .mode = TC_FILE_MODE,
+ .i_fop = &members_fileops,
+ .i_op = &rcfs_file_inode_operations,
+ },
+ {
+ .name = "stats",
+ .mode = TC_FILE_MODE,
+ .i_fop = &stats_fileops,
+ .i_op = &rcfs_file_inode_operations,
+ },
+ {
+ .name = "shares",
+ .mode = TC_FILE_MODE,
+ .i_fop = &shares_fileops,
+ .i_op = &rcfs_file_inode_operations,
+ },
+ /*
+ * Reclassify and Config should be made available only at the
+ * root level. Make sure they are the last two entries, as
+ * rcfs_mkdir depends on it.
+ */
+ {
+ .name = "reclassify",
+ .mode = TC_FILE_MODE,
+ .i_fop = &reclassify_fileops,
+ .i_op = &rcfs_file_inode_operations,
+ },
+ {
+ .name = "config",
+ .mode = TC_FILE_MODE,
+ .i_fop = &config_fileops,
+ .i_op = &rcfs_file_inode_operations,
+ },
+};
+
+struct rcfs_mfdesc tc_mfdesc = {
+ .rootmf = tc_rootdesc,
+ .rootmflen = NR_TCROOTMF,
+};
Index: linux-2.6.12-ckrm1/include/linux/ckrm_tc.h
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ linux-2.6.12-ckrm1/include/linux/ckrm_tc.h 2005-06-20 13:08:31.000000000 -0700
@@ -0,0 +1,46 @@
+/* ckrm_tc.h - Header file to be used by task class users
+ *
+ * Copyright (C) Hubertus Franke, IBM Corp. 2003, 2004
+ *
+ * Provides data structures, macros and kernel API for the
+ * classtype, taskclass.
+ *
+ * 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 version 2.1 of the GNU Lesser General Public License
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ */
+
+#ifndef _LINUX_CKRM_TC_H_
+#define _LINUX_CKRM_TC_H_
+
+#ifdef CONFIG_CKRM_TYPE_TASKCLASS
+#include <linux/ckrm_rc.h>
+
+#define TASK_CLASS_TYPE_NAME "taskclass"
+
+struct ckrm_task_class {
+ struct ckrm_core_class core;
+};
+
+/*
+ * Index into genmfdesc array, defined in rcfs/dir_modules.c,
+ * which has the mfdesc entry that taskclass wants to use.
+ */
+#define TC_MF_IDX 0
+
+extern int ckrm_forced_reclassify_pid(int, struct ckrm_task_class *);
+
+#else /* CONFIG_CKRM_TYPE_TASKCLASS */
+
+#define ckrm_forced_reclassify_pid(a, b) (0)
+
+#endif
+
+#endif /* _LINUX_CKRM_TC_H_ */
Index: linux-2.6.12-ckrm1/include/linux/sched.h
===================================================================
--- linux-2.6.12-ckrm1.orig/include/linux/sched.h 2005-06-20 13:08:29.000000000 -0700
+++ linux-2.6.12-ckrm1/include/linux/sched.h 2005-06-20 13:08:31.000000000 -0700
@@ -741,14 +741,17 @@ struct task_struct {
nodemask_t mems_allowed;
int cpuset_mems_generation;
#endif
-#ifdef CONFIG_DELAY_ACCT
- struct task_delay_info delays;
-#endif
#ifdef CONFIG_CKRM
spinlock_t ckrm_tsklock;
void *ce_data;
+#ifdef CONFIG_CKRM_TYPE_TASKCLASS
+ struct ckrm_task_class *taskclass;
+ struct list_head taskclass_link;
+#endif /* CONFIG_CKRM_TYPE_TASKCLASS */
+#endif /* CONFIG_CKRM */
+#ifdef CONFIG_DELAY_ACCT
+ struct task_delay_info delays;
#endif
-
};

static inline pid_t process_group(struct task_struct *tsk)
Index: linux-2.6.12-ckrm1/init/Kconfig
===================================================================
--- linux-2.6.12-ckrm1.orig/init/Kconfig 2005-06-20 13:08:30.000000000 -0700
+++ linux-2.6.12-ckrm1/init/Kconfig 2005-06-20 13:08:31.000000000 -0700
@@ -170,6 +170,18 @@ config RCFS_FS

Say M if unsure, Y to save on module loading. N doesn't make sense
when CKRM has been configured.
+
+config CKRM_TYPE_TASKCLASS
+ bool "Class Manager for Task Groups"
+ depends on CKRM && RCFS_FS
+ default y
+ help
+ TASKCLASS provides the extensions for CKRM to track task classes
+ This is the base to enable task class based resource control for
+ cpu, memory and disk I/O.
+
+ Say Y if unsure
+
endmenu

config SYSCTL
Index: linux-2.6.12-ckrm1/kernel/ckrm/ckrm_tc.c
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ linux-2.6.12-ckrm1/kernel/ckrm/ckrm_tc.c 2005-06-20 13:08:31.000000000 -0700
@@ -0,0 +1,745 @@
+/* ckrm_tc.c - Class-based Kernel Resource Management (CKRM)
+ *
+ * Copyright (C) Hubertus Franke, IBM Corp. 2003,2004
+ * (C) Shailabh Nagar, IBM Corp. 2003
+ * (C) Chandra Seetharaman, IBM Corp. 2003
+ * (C) Vivek Kashyap, IBM Corp. 2004
+ *
+ *
+ * Provides kernel API of CKRM for in-kernel,per-resource controllers
+ * (one each for cpu, memory, io, network) and callbacks for
+ * classification modules.
+ *
+ * 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.
+ *
+ */
+
+#include <linux/config.h>
+#include <linux/init.h>
+#include <linux/linkage.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <asm/uaccess.h>
+#include <linux/mm.h>
+#include <asm/errno.h>
+#include <linux/string.h>
+#include <linux/list.h>
+#include <linux/spinlock.h>
+#include <linux/module.h>
+#include <linux/ckrm_rc.h>
+
+#include <linux/ckrm_tc.h>
+
+static struct ckrm_task_class taskclass_dflt_class = {
+};
+
+const char *dflt_taskclass_name = TASK_CLASS_TYPE_NAME;
+
+static struct ckrm_core_class *ckrm_alloc_task_class(struct ckrm_core_class
+ *parent, const char *name);
+static int ckrm_free_task_class(struct ckrm_core_class *core);
+
+static int tc_forced_reclassify(struct ckrm_core_class * target,
+ const char *resname);
+static int tc_show_members(struct ckrm_core_class *core, struct seq_file *seq);
+static void tc_add_resctrl(struct ckrm_core_class *core, int resid);
+
+struct ckrm_classtype ct_taskclass = {
+ .mfidx = TC_MF_IDX,
+ .name = TASK_CLASS_TYPE_NAME,
+ .type_id = CKRM_CLASSTYPE_TASK_CLASS,
+ .maxdepth = 3, /* starting point */
+ .resid_reserved = 4,
+ .max_res_ctlrs = CKRM_MAX_RES_CTLRS,
+ .max_resid = 0,
+ .bit_res_ctlrs = 0L,
+ .res_ctlrs_lock = SPIN_LOCK_UNLOCKED,
+ .classes = LIST_HEAD_INIT(ct_taskclass.classes),
+
+ .default_class = &taskclass_dflt_class.core,
+
+ /* private version of functions */
+ .alloc = &ckrm_alloc_task_class,
+ .free = &ckrm_free_task_class,
+ .show_members = &tc_show_members,
+ .forced_reclassify = &tc_forced_reclassify,
+
+ /* use of default functions */
+ .show_shares = &ckrm_class_show_shares,
+ .show_stats = &ckrm_class_show_stats,
+ .show_config = &ckrm_class_show_config,
+ .set_config = &ckrm_class_set_config,
+ .set_shares = &ckrm_class_set_shares,
+ .reset_stats = &ckrm_class_reset_stats,
+
+ /* mandatory private version; no default available */
+ .add_resctrl = &tc_add_resctrl,
+};
+
+/*
+ * Change the task class of the given task.
+ *
+ * Change the task's task class to "newcls" if the task's current
+ * class (task->taskclass) is same as given "oldcls", if it is non-NULL.
+ *
+ * Caller is responsible to make sure the task structure stays put through
+ * this function.
+ *
+ * This function should be called with the following locks NOT held
+ * - tsk->ckrm_tsklock
+ * - core->ckrm_lock, if core is NULL then ckrm_dflt_class.ckrm_lock
+ * - tsk->taskclass->ckrm_lock
+ *
+ * Function is also called with a ckrm_core_grab on the new core, hence
+ * it needs to be dropped if no assignment takes place.
+ */
+static void
+ckrm_set_taskclass(struct task_struct *tsk, struct ckrm_task_class *newcls,
+ struct ckrm_task_class *oldcls, enum ckrm_event event)
+{
+ int i;
+ struct ckrm_classtype *clstype;
+ struct ckrm_res_ctlr *rcbs;
+ struct ckrm_task_class *curcls;
+ void *old_res_class, *new_res_class;
+ int drop_old_cls;
+
+ spin_lock(&tsk->ckrm_tsklock);
+ curcls = tsk->taskclass;
+
+ if ((void *)-1 == curcls) {
+ /* task is disassociated from ckrm. Don't bother it. */
+ spin_unlock(&tsk->ckrm_tsklock);
+ ckrm_core_drop(class_core(newcls));
+ return;
+ }
+
+ if ((curcls == NULL) && (newcls == (void *)-1)) {
+ /*
+ * Task needs to disassociated from ckrm and has no circles
+ * just disassociate and return.
+ */
+ tsk->taskclass = newcls;
+ spin_unlock(&tsk->ckrm_tsklock);
+ return;
+ }
+ if (oldcls && (oldcls != curcls)) {
+ spin_unlock(&tsk->ckrm_tsklock);
+ if (newcls) {
+ /* compensate for previous grab */
+ pr_debug("(%s:%d): Race-condition caught <%s> %d\n",
+ tsk->comm, tsk->pid, class_core(newcls)->name,
+ event);
+ ckrm_core_drop(class_core(newcls));
+ }
+ return;
+ }
+ /* Make sure we have a real destination core. */
+ if (!newcls) {
+ newcls = &taskclass_dflt_class;
+ ckrm_core_grab(class_core(newcls));
+ }
+ /* Take out of old class and drop the oldcore. */
+ if ((drop_old_cls = (curcls != NULL))) {
+ class_lock(class_core(curcls));
+ if (newcls == curcls) {
+ /*
+ * We are already in the destination class.
+ * we still need to drop oldcore.
+ */
+ class_unlock(class_core(curcls));
+ spin_unlock(&tsk->ckrm_tsklock);
+ goto out;
+ }
+ list_del(&tsk->taskclass_link);
+ INIT_LIST_HEAD(&tsk->taskclass_link);
+ tsk->taskclass = NULL;
+ class_unlock(class_core(curcls));
+ if (newcls == (void *)-1) {
+ tsk->taskclass = newcls;
+ spin_unlock(&tsk->ckrm_tsklock);
+
+ /* still need to get out of old class. */
+ newcls = NULL;
+ goto rc_handling;
+ }
+ }
+ /* put into new class */
+ class_lock(class_core(newcls));
+ tsk->taskclass = newcls;
+ list_add(&tsk->taskclass_link, &class_core(newcls)->objlist);
+ class_unlock(class_core(newcls));
+
+ if (newcls == curcls) {
+ spin_unlock(&tsk->ckrm_tsklock);
+ goto out;
+ }
+
+ CE_NOTIFY(&ct_taskclass, event, newcls, tsk);
+
+ spin_unlock(&tsk->ckrm_tsklock);
+
+ rc_handling:
+ clstype = &ct_taskclass;
+ if (clstype->bit_res_ctlrs) {
+ /* avoid running through the entire list if none are registered */
+ for (i = 0; i < clstype->max_resid; i++) {
+ if (clstype->res_ctlrs[i] == NULL)
+ continue;
+ atomic_inc(&clstype->nr_resusers[i]);
+ old_res_class =
+ curcls ? class_core(curcls)->res_class[i] : NULL;
+ new_res_class =
+ newcls ? class_core(newcls)->res_class[i] : NULL;
+ rcbs = clstype->res_ctlrs[i];
+ if (rcbs && rcbs->change_resclass
+ && (old_res_class != new_res_class))
+ (*rcbs->change_resclass) (tsk, old_res_class,
+ new_res_class);
+ atomic_dec(&clstype->nr_resusers[i]);
+ }
+ }
+
+ out:
+ if (drop_old_cls)
+ ckrm_core_drop(class_core(curcls));
+ return;
+}
+
+static void tc_add_resctrl(struct ckrm_core_class *core, int resid)
+{
+ struct task_struct *tsk;
+ struct ckrm_res_ctlr *rcbs;
+
+ if ((resid < 0) || (resid >= CKRM_MAX_RES_CTLRS)
+ || ((rcbs = core->classtype->res_ctlrs[resid]) == NULL))
+ return;
+
+ class_lock(core);
+ list_for_each_entry(tsk, &core->objlist, taskclass_link) {
+ if (rcbs->change_resclass)
+ (*rcbs->change_resclass) (tsk, (void *)-1,
+ core->res_class[resid]);
+ }
+ class_unlock(core);
+}
+
+/**************************************************************************
+ * Functions called from classification points *
+ **************************************************************************/
+
+#define CE_CLASSIFY_TASK(event, tsk) \
+do { \
+ struct ckrm_task_class *newcls = NULL; \
+ struct ckrm_task_class *oldcls = tsk->taskclass; \
+ \
+ CE_CLASSIFY_RET(newcls,&ct_taskclass,event,tsk); \
+ if (newcls) { \
+ /* called synchrously. no need to get task struct */ \
+ ckrm_set_taskclass(tsk, newcls, oldcls, event); \
+ } \
+} while (0)
+
+
+#define CE_CLASSIFY_TASK_PROTECT(event, tsk) \
+do { \
+ ce_protect(&ct_taskclass); \
+ CE_CLASSIFY_TASK(event,tsk); \
+ ce_release(&ct_taskclass); \
+} while (0)
+
+static void cb_taskclass_newtask(struct task_struct *tsk)
+{
+ tsk->taskclass = NULL;
+ INIT_LIST_HEAD(&tsk->taskclass_link);
+}
+
+static void cb_taskclass_fork(struct task_struct *tsk)
+{
+ struct ckrm_task_class *cls = NULL;
+
+ pr_debug("%p:%d:%s\n", tsk, tsk->pid, tsk->comm);
+
+ ce_protect(&ct_taskclass);
+ CE_CLASSIFY_RET(cls, &ct_taskclass, CKRM_EVENT_FORK, tsk);
+ if (cls == NULL) {
+ spin_lock(&tsk->parent->ckrm_tsklock);
+ cls = tsk->parent->taskclass;
+ ckrm_core_grab(class_core(cls));
+ spin_unlock(&tsk->parent->ckrm_tsklock);
+ }
+ if (!list_empty(&tsk->taskclass_link))
+ pr_debug("cb_taskclass_fork: BUG in cb_fork.. tsk (%s:%d> already linked\n",
+ tsk->comm, tsk->pid);
+
+ ckrm_set_taskclass(tsk, cls, NULL, CKRM_EVENT_FORK);
+ ce_release(&ct_taskclass);
+}
+
+static void cb_taskclass_exit(struct task_struct *tsk)
+{
+ CE_CLASSIFY_NORET(&ct_taskclass, CKRM_EVENT_EXIT, tsk);
+ ckrm_set_taskclass(tsk, (void *)-1, NULL, CKRM_EVENT_EXIT);
+}
+
+static void cb_taskclass_exec(const char *filename)
+{
+ pr_debug("%p:%d:%s <%s>\n", current, current->pid, current->comm,
+ filename);
+ CE_CLASSIFY_TASK_PROTECT(CKRM_EVENT_EXEC, current);
+}
+
+static void cb_taskclass_uid(void)
+{
+ pr_debug("%p:%d:%s\n", current, current->pid, current->comm);
+ CE_CLASSIFY_TASK_PROTECT(CKRM_EVENT_UID, current);
+}
+
+static void cb_taskclass_gid(void)
+{
+ pr_debug("%p:%d:%s\n", current, current->pid, current->comm);
+ CE_CLASSIFY_TASK_PROTECT(CKRM_EVENT_GID, current);
+}
+
+static struct ckrm_event_spec taskclass_events_callbacks[] = {
+ {CKRM_EVENT_NEWTASK, { cb_taskclass_newtask, NULL}},
+ {CKRM_EVENT_EXEC, { cb_taskclass_exec, NULL }},
+ {CKRM_EVENT_FORK, { cb_taskclass_fork, NULL }},
+ {CKRM_EVENT_EXIT, { cb_taskclass_exit, NULL }},
+ {CKRM_EVENT_UID, { cb_taskclass_uid, NULL }},
+ {CKRM_EVENT_GID, { cb_taskclass_gid, NULL }},
+ {-1, { -1, NULL }}
+};
+
+/*
+ * Asynchronous callback functions (driven by RCFS)
+ *
+ * Async functions force a setting of the task structure
+ * synchronous callbacks are protected against race conditions
+ * by using a cmpxchg on the core before setting it.
+ * Async calls need to be serialized to ensure they can't
+ * race against each other
+ */
+
+static DECLARE_MUTEX(ckrm_async_serializer); /* serialize all async functions */
+
+/*
+ * Go through the task list and reclassify all tasks according to the current
+ * classification rules.
+ *
+ * We have the problem that we can not hold any lock (including the
+ * tasklist_lock) while classifying. Two methods possible
+ *
+ * (a) go through entire pidrange (0..pidmax) and if a task exists at
+ * that pid then reclassify it
+ * (b) go several time through task list and build a bitmap for a particular
+ * subrange of pid otherwise the memory requirements ight be too much.
+ *
+ * We use a hybrid by comparing ratio nr_threads/pidmax
+ */
+
+static int ckrm_reclassify_all_tasks(void)
+{
+ extern int pid_max;
+
+ struct task_struct *proc, *thread;
+ int i;
+ int curpidmax = pid_max;
+ int ratio;
+ int use_bitmap;
+
+ /* Check permissions */
+ if ((!capable(CAP_SYS_NICE)) && (!capable(CAP_SYS_RESOURCE))) {
+ return -EPERM;
+ }
+
+ ratio = curpidmax / nr_threads;
+ if (curpidmax <= PID_MAX_DEFAULT) {
+ use_bitmap = 1;
+ } else {
+ use_bitmap = (ratio >= 2);
+ }
+
+ ce_protect(&ct_taskclass);
+
+ retry:
+
+ if (use_bitmap == 0) {
+ /* Go through it in one walk. */
+ read_lock(&tasklist_lock);
+ for (i = 0; i < curpidmax; i++) {
+ if ((thread = find_task_by_pid(i)) == NULL)
+ continue;
+ get_task_struct(thread);
+ read_unlock(&tasklist_lock);
+ CE_CLASSIFY_TASK(CKRM_EVENT_RECLASSIFY, thread);
+ put_task_struct(thread);
+ read_lock(&tasklist_lock);
+ }
+ read_unlock(&tasklist_lock);
+ } else {
+ unsigned long *bitmap;
+ int bitmapsize;
+ int order = 0;
+ int num_loops;
+ int pid, do_next;
+
+ bitmap = (unsigned long *)__get_free_pages(GFP_KERNEL, order);
+ if (bitmap == NULL) {
+ use_bitmap = 0;
+ goto retry;
+ }
+
+ bitmapsize = 8 * (1 << (order + PAGE_SHIFT));
+ num_loops = (curpidmax + bitmapsize - 1) / bitmapsize;
+
+ do_next = 1;
+ for (i = 0; i < num_loops && do_next; i++) {
+ int pid_start = i * bitmapsize;
+ int pid_end = pid_start + bitmapsize;
+ int num_found = 0;
+ int pos;
+
+ memset(bitmap, 0, bitmapsize / 8); /* start afresh */
+ do_next = 0;
+
+ read_lock(&tasklist_lock);
+ do_each_thread(proc, thread) {
+ pid = thread->pid;
+ if ((pid < pid_start) || (pid >= pid_end)) {
+ if (pid >= pid_end) {
+ do_next = 1;
+ }
+ continue;
+ }
+ pid -= pid_start;
+ set_bit(pid, bitmap);
+ num_found++;
+ }
+ while_each_thread(proc, thread);
+ read_unlock(&tasklist_lock);
+
+ if (num_found == 0)
+ continue;
+
+ pos = 0;
+ for (; num_found--;) {
+ pos = find_next_bit(bitmap, bitmapsize, pos);
+ pid = pos + pid_start;
+
+ read_lock(&tasklist_lock);
+ if ((thread = find_task_by_pid(pid)) != NULL) {
+ get_task_struct(thread);
+ read_unlock(&tasklist_lock);
+ CE_CLASSIFY_TASK(CKRM_EVENT_RECLASSIFY,
+ thread);
+ put_task_struct(thread);
+ } else {
+ read_unlock(&tasklist_lock);
+ }
+ pos++;
+ }
+ }
+
+ }
+ ce_release(&ct_taskclass);
+ return 0;
+}
+
+/*
+ * Reclassify all tasks in the given core class.
+ */
+
+static void ckrm_reclassify_class_tasks(struct ckrm_task_class *cls)
+{
+ int ce_regd;
+ struct ckrm_hnode *cnode;
+ struct ckrm_task_class *parcls;
+ int num = 0;
+
+ if (!ckrm_validate_and_grab_core(&cls->core))
+ return;
+
+ down(&ckrm_async_serializer);
+ pr_debug("start %p:%s:%d:%d\n", cls, cls->core.name,
+ atomic_read(&cls->core.refcnt),
+ atomic_read(&cls->core.hnode.parent->refcnt));
+ /*
+ * If no CE registered for this classtype, following will be needed
+ * repeatedly.
+ */
+ ce_regd = atomic_read(&class_core(cls)->classtype->ce_regd);
+ cnode = &(class_core(cls)->hnode);
+ parcls = class_type(struct ckrm_task_class, cnode->parent);
+
+ next_task:
+ class_lock(class_core(cls));
+ if (!list_empty(&class_core(cls)->objlist)) {
+ struct ckrm_task_class *newcls = NULL;
+ struct task_struct *tsk =
+ list_entry(class_core(cls)->objlist.next,
+ struct task_struct, taskclass_link);
+
+ get_task_struct(tsk);
+ class_unlock(class_core(cls));
+
+ if (ce_regd) {
+ CE_CLASSIFY_RET(newcls, &ct_taskclass,
+ CKRM_EVENT_RECLASSIFY, tsk);
+ if (cls == newcls) {
+ /*
+ * Don't allow reclassifying to the same class
+ * as we are in the process of cleaning up
+ * this class
+ */
+
+ /* compensate for CE's grab */
+ ckrm_core_drop(class_core(newcls));
+ newcls = NULL;
+ }
+ }
+ if (newcls == NULL) {
+ newcls = parcls;
+ ckrm_core_grab(class_core(newcls));
+ }
+ ckrm_set_taskclass(tsk, newcls, cls, CKRM_EVENT_RECLASSIFY);
+ put_task_struct(tsk);
+ num++;
+ goto next_task;
+ }
+ pr_debug("stop %p:%s:%d:%d %d\n", cls, cls->core.name,
+ atomic_read(&cls->core.refcnt),
+ atomic_read(&cls->core.hnode.parent->refcnt), num);
+ class_unlock(class_core(cls));
+ ckrm_core_drop(class_core(cls));
+
+ up(&ckrm_async_serializer);
+
+ return;
+}
+
+/*
+ * Change the core class of the given task
+ */
+
+int ckrm_forced_reclassify_pid(pid_t pid, struct ckrm_task_class *cls)
+{
+ struct task_struct *tsk;
+
+ if (cls && !ckrm_validate_and_grab_core(class_core(cls)))
+ return -EINVAL;
+
+ read_lock(&tasklist_lock);
+ if ((tsk = find_task_by_pid(pid)) == NULL) {
+ read_unlock(&tasklist_lock);
+ if (cls)
+ ckrm_core_drop(class_core(cls));
+ return -EINVAL;
+ }
+ get_task_struct(tsk);
+ read_unlock(&tasklist_lock);
+
+ /* Check permissions */
+ if ((!capable(CAP_SYS_NICE)) &&
+ (!capable(CAP_SYS_RESOURCE)) && (current->user != tsk->user)) {
+ if (cls)
+ ckrm_core_drop(class_core(cls));
+ put_task_struct(tsk);
+ return -EPERM;
+ }
+
+ ce_protect(&ct_taskclass);
+ if (cls == NULL)
+ CE_CLASSIFY_TASK(CKRM_EVENT_RECLASSIFY,tsk);
+ else
+ ckrm_set_taskclass(tsk, cls, NULL, CKRM_EVENT_MANUAL);
+
+ ce_release(&ct_taskclass);
+ put_task_struct(tsk);
+
+ return 0;
+}
+
+static struct ckrm_core_class *ckrm_alloc_task_class(struct ckrm_core_class
+ *parent, const char *name)
+{
+ struct ckrm_task_class *taskcls;
+ taskcls = kmalloc(sizeof(struct ckrm_task_class), GFP_KERNEL);
+ if (taskcls == NULL)
+ return NULL;
+ memset(taskcls, 0, sizeof(struct ckrm_task_class));
+
+ ckrm_init_core_class(&ct_taskclass, class_core(taskcls), parent, name);
+
+ ce_protect(&ct_taskclass);
+ if (ct_taskclass.ce_cb_active && ct_taskclass.ce_callbacks.class_add)
+ (*ct_taskclass.ce_callbacks.class_add) (name, taskcls,
+ ct_taskclass.type_id);
+ ce_release(&ct_taskclass);
+
+ return class_core(taskcls);
+}
+
+static int ckrm_free_task_class(struct ckrm_core_class *core)
+{
+ struct ckrm_task_class *taskcls;
+
+ if (!ckrm_is_core_valid(core)) {
+ return (-EINVAL); /* Invalid core */
+ }
+ if (core == core->classtype->default_class) {
+ /* reset the name tag */
+ core->name = dflt_taskclass_name;
+ return 0;
+ }
+
+ pr_debug("%p:%s:%d\n", core, core->name, atomic_read(&core->refcnt));
+
+ taskcls = class_type(struct ckrm_task_class, core);
+
+ ce_protect(&ct_taskclass);
+
+ if (ct_taskclass.ce_cb_active && ct_taskclass.ce_callbacks.class_delete)
+ (*ct_taskclass.ce_callbacks.class_delete) (core->name, taskcls,
+ ct_taskclass.type_id);
+ ckrm_reclassify_class_tasks(taskcls);
+
+ ce_release(&ct_taskclass);
+
+ ckrm_release_core_class(core);
+ return 0;
+}
+
+void __init ckrm_meta_init_taskclass(void)
+{
+ pr_debug("...... Initializing ClassType<%s> ........\n",
+ ct_taskclass.name);
+ /* intialize the default class */
+ ckrm_init_core_class(&ct_taskclass, class_core(&taskclass_dflt_class),
+ NULL, dflt_taskclass_name);
+
+ /* register classtype and initialize default task class */
+ ckrm_register_classtype(&ct_taskclass);
+ ckrm_register_event_set(taskclass_events_callbacks);
+
+ /*
+ * note registeration of all resource controllers will be done
+ * later dynamically as these are specified as modules
+ */
+}
+
+static int tc_show_members(struct ckrm_core_class *core, struct seq_file *seq)
+{
+ struct list_head *lh;
+ struct task_struct *tsk;
+
+ class_lock(core);
+ list_for_each(lh, &core->objlist) {
+ tsk = container_of(lh, struct task_struct, taskclass_link);
+ seq_printf(seq, "%ld\n", (long)tsk->pid);
+ }
+ class_unlock(core);
+
+ return 0;
+}
+
+static int tc_forced_reclassify(struct ckrm_core_class *target, const char *obj)
+{
+ pid_t pid;
+ int rc = -EINVAL;
+
+ pid = (pid_t) simple_strtol(obj, NULL, 0);
+
+ down(&ckrm_async_serializer); /* protect against race with reclassify_class */
+ if (pid < 0) {
+ /* TBD: We could treat this as a process group. */
+ rc = -EINVAL;
+ } else if (pid == 0) {
+ rc = (target == NULL) ? ckrm_reclassify_all_tasks() : -EINVAL;
+ } else {
+ struct ckrm_task_class *cls = NULL;
+ if (target)
+ cls = class_type(struct ckrm_task_class, target);
+ rc = ckrm_forced_reclassify_pid(pid,cls);
+ }
+ up(&ckrm_async_serializer);
+ return rc;
+}
+
+#if 0
+
+/******************************************************************************
+ * Debugging Task Classes: Utility functions
+ ******************************************************************************/
+
+void check_tasklist_sanity(struct ckrm_task_class *cls)
+{
+ struct ckrm_core_class *core = class_core(cls);
+ struct list_head *lh1, *lh2;
+ int count = 0;
+
+ if (core) {
+ class_lock(core);
+ if (list_empty(&core->objlist)) {
+ class_lock(core);
+ pr_debug("check_tasklist_sanity: class %s empty list\n",
+ core->name);
+ return;
+ }
+ list_for_each_safe(lh1, lh2, &core->objlist) {
+ struct task_struct *tsk =
+ container_of(lh1, struct task_struct,
+ taskclass_link);
+ if (count++ > 20000) {
+ pr_debug("check_tasklist_sanity: CKRM taskclass list is CORRUPTED\n");
+ break;
+ }
+ if (tsk->taskclass != cls) {
+ const char *tclsname;
+ tclsname = (tsk->taskclass) ?
+ class_core(tsk->taskclass)->name:"NULL";
+ pr_debug("sanity: task %s:%d has ckrm_core "
+ "|%s| but in list |%s|\n", tsk->comm,
+ tsk->pid, tclsname, core->name);
+ }
+ }
+ class_unlock(core);
+ }
+}
+
+void ckrm_debug_free_task_class(struct ckrm_task_class *tskcls)
+{
+ struct task_struct *proc, *thread;
+ int count = 0;
+
+ pr_debug("ckrm_debug_free_task_class: Analyze Error <%s> %d\n",
+ class_core(tskcls)->name,
+ atomic_read(&(class_core(tskcls)->refcnt)));
+
+ read_lock(&tasklist_lock);
+ class_lock(class_core(tskcls));
+ do_each_thread(proc, thread) {
+ count += (tskcls == thread->taskclass);
+ if ((thread->taskclass == tskcls) || (tskcls == NULL)) {
+ const char *tclsname;
+ tclsname = (thread->taskclass) ?
+ class_core(thread->taskclass)->name :"NULL";
+ pr_debug("ckrm-debug_free_task_class: %d thread=<%s:%d> -> <%s> <%lx>\n", count,
+ thread->comm, thread->pid, tclsname,
+ thread->flags & PF_EXITING);
+ }
+ } while_each_thread(proc, thread);
+ class_unlock(class_core(tskcls));
+ read_unlock(&tasklist_lock);
+
+ pr_debug("ckrm_debug_free_task_class: End Analyze Error <%s> %d\n",
+ class_core(tskcls)->name,
+ atomic_read(&(class_core(tskcls)->refcnt)));
+}
+
+#endif
Index: linux-2.6.12-ckrm1/kernel/ckrm/Makefile
===================================================================
--- linux-2.6.12-ckrm1.orig/kernel/ckrm/Makefile 2005-06-20 13:08:29.000000000 -0700
+++ linux-2.6.12-ckrm1/kernel/ckrm/Makefile 2005-06-20 13:08:31.000000000 -0700
@@ -3,3 +3,4 @@
#

obj-y += ckrm_events.o ckrm.o ckrmutils.o
+obj-$(CONFIG_CKRM_TYPE_TASKCLASS) += ckrm_tc.o

--