[PATCH] CKRM: 5/10 CKRM: Task based management for CPU, memory and Disk I/O.

* [PATCH] CKRM: 5/10 CKRM:  Task based management for CPU, memory and Disk I/O.
@ 2004-11-29 18:49 Gerrit Huizenga
  2004-11-29 22:23 ` Greg KH
  0 siblings, 1 reply; 3+ messages in thread
From: Gerrit Huizenga @ 2004-11-29 18:49 UTC (permalink / raw)
  To: linux-kernel; +Cc: akpm, Rik van Riel, Chris Mason, ckrm-tech

 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>

Index: linux-2.6.10-rc2/fs/rcfs/Makefile
===================================================================

--- linux-2.6.10-rc2.orig/fs/rcfs/Makefile	2004-11-19 20:44:18.000000000 -0800
+++ linux-2.6.10-rc2/fs/rcfs/Makefile	2004-11-22 14:51:22.322145341 -0800
@@ -3,4 +3,6 @@
 #
 
 obj-$(CONFIG_RCFS_FS) += rcfs.o 
-rcfs-objs := super.o inode.o dir.o rootdir.o magic.o
+rcfs-objs := super.o inode.o dir.o rootdir.o magic.o tc_magic.o
+
+rcfs-objs-$(CONFIG_CKRM_TYPE_TASKCLASS) += tc_magic.o
Index: linux-2.6.10-rc2/fs/rcfs/rootdir.c
===================================================================
--- linux-2.6.10-rc2.orig/fs/rcfs/rootdir.c	2004-11-19 20:44:18.000000000 -0800
+++ linux-2.6.10-rc2/fs/rcfs/rootdir.c	2004-11-22 14:51:22.322145341 -0800
@@ -194,6 +194,10 @@
 
 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 
@@ -204,6 +208,10 @@
  * 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-2.6.10-rc2/fs/rcfs/tc_magic.c
===================================================================
--- /dev/null	1970-01-01 00:00:00.000000000 +0000
+++ linux-2.6.10-rc2/fs/rcfs/tc_magic.c	2004-11-22 14:51:22.323145182 -0800
@@ -0,0 +1,100 @@
+/* 
+ * 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.
+ *
+ */
+
+/* Changes
+ *
+ * 23 Apr 2004
+ *        Created.
+ *
+ */
+
+#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-2.6.10-rc2/include/linux/ckrm_tc.h
===================================================================
--- /dev/null	1970-01-01 00:00:00.000000000 +0000
+++ linux-2.6.10-rc2/include/linux/ckrm_tc.h	2004-11-22 14:51:22.324145024 -0800
@@ -0,0 +1,50 @@
+/* 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.
+ *
+ */
+
+/* Changes
+ *
+ * 12 Apr 2004
+ *        Created.
+ */
+
+#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"
+
+typedef struct ckrm_task_class {
+	struct ckrm_core_class core;
+} ckrm_task_class_t;
+
+// 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-2.6.10-rc2/include/linux/sched.h
===================================================================
--- linux-2.6.10-rc2.orig/include/linux/sched.h	2004-11-19 20:43:43.000000000 -0800
+++ linux-2.6.10-rc2/include/linux/sched.h	2004-11-22 14:51:22.335143281 -0800
@@ -665,14 +665,17 @@
   	struct mempolicy *mempolicy;
   	short il_next;		/* could be shared with used_math */
 #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-2.6.10-rc2/init/Kconfig
===================================================================
--- linux-2.6.10-rc2.orig/init/Kconfig	2004-11-19 20:44:18.000000000 -0800
+++ linux-2.6.10-rc2/init/Kconfig	2004-11-22 14:51:22.349141064 -0800
@@ -163,6 +163,16 @@
 	  Say N if unsure, Y if you've enabled CKRM, M to debug rcfs 
 	  initialization.
 
+config CKRM_TYPE_TASKCLASS
+	bool "Class Manager for Task Groups"
+	depends on CKRM && RCFS_FS
+	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 N if unsure 
+
 endmenu
 
 config SYSCTL
Index: linux-2.6.10-rc2/kernel/ckrm/ckrm_tc.c
===================================================================
--- /dev/null	1970-01-01 00:00:00.000000000 +0000
+++ linux-2.6.10-rc2/kernel/ckrm/ckrm_tc.c	2004-11-22 14:51:22.351140747 -0800
@@ -0,0 +1,787 @@
+/* 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.
+ *
+ */
+
+/* Changes
+ *
+ * 28 Aug 2003
+ *        Created.
+ * 06 Nov 2003
+ *        Made modifications to suit the new RBCE module.
+ * 10 Nov 2003
+ *        Fixed a bug in fork and exit callbacks. Added callbacks_active and
+ *        surrounding logic. Added task paramter for all CE callbacks.
+ * 23 Mar 2004
+ *        moved to referenced counted class objects and correct locking
+ * 12 Apr 2004
+ *        introduced adopted to emerging classtype interface
+ */
+
+#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>
+
+#define TC_DEBUG(fmt, args...) do { \
+/* printk("%s: " fmt, __FUNCTION__ , ## args); */ } while (0)
+
+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(ckrm_core_class_t * 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,
+	.typeID = CKRM_CLASSTYPE_TASK_CLASS,
+	.maxdepth = 3,		// Hubertus .. just to start 
+	.resid_reserved = 4,	// Hubertus .. reservation
+	.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 dflt available
+	.add_resctrl = &tc_add_resctrl,
+};
+
+/**************************************************************************
+ *                   Helper Functions                                     *
+ **************************************************************************/
+
+static inline void ckrm_init_task_lock(struct task_struct *tsk)
+{
+	tsk->ckrm_tsklock = SPIN_LOCK_UNLOCKED;
+}
+
+// Hubertus .. following functions should move to ckrm_rc.h
+
+static inline void ckrm_task_lock(struct task_struct *tsk)
+{
+	spin_lock(&tsk->ckrm_tsklock);
+}
+
+static inline void ckrm_task_unlock(struct task_struct *tsk)
+{
+	spin_unlock(&tsk->ckrm_tsklock);
+}
+
+/*
+ * 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_task_lock
+ * 	- 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, ckrm_task_class_t * newcls,
+		   ckrm_task_class_t * oldcls, enum ckrm_event event)
+{
+	int i;
+	ckrm_classtype_t *clstype;
+	ckrm_res_ctlr_t *rcbs;
+	ckrm_task_class_t *curcls;
+	void *old_res_class, *new_res_class;
+	int drop_old_cls;
+
+	ckrm_task_lock(tsk);
+	curcls = tsk->taskclass;
+
+	if ((void *)-1 == curcls) {
+		// task is disassociated from ckrm... don't bother it.
+		ckrm_task_unlock(tsk);
+		ckrm_core_drop(class_core(newcls));
+		return;
+	}
+
+	if ((curcls == NULL) && (newcls == (void *)-1)) {
+		// task need to disassociated from ckrm and has no curcls
+		// just disassociate and return.
+		tsk->taskclass = newcls;
+		ckrm_task_unlock(tsk);
+		return;
+	}
+	// check whether compare_and_exchange should
+	if (oldcls && (oldcls != curcls)) {
+		ckrm_task_unlock(tsk);
+		if (newcls) {
+			/* compensate for previous grab */
+			TC_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 
+	// remember that we need to 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));
+			ckrm_task_unlock(tsk);
+			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;
+			ckrm_task_unlock(tsk);
+			// 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) {
+		ckrm_task_unlock(tsk);
+		goto out;
+	}
+
+	CE_NOTIFY(&CT_taskclass, event, newcls, tsk);
+
+	ckrm_task_unlock(tsk);
+
+      rc_handling:
+	clstype = &CT_taskclass;
+	if (clstype->bit_res_ctlrs) {	
+		// avoid running through the entire list if non is 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;
+}
+
+// HF SUGGEST: we could macro-tize this for other types 
+// DEF_FUNC_ADD_RESCTRL(funcname,link)
+//          would DEF_FUNC_ADD_RESCTRL(tc_add_resctrl,taskclass_link)
+
+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 ECB_PRINTK(fmt, args...)				\
+// do { if (CT_taskclass.ce_regd)				 
+// printk("%s: " fmt, __FUNCTION__ , ## args); } while (0)
+
+#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;
+
+	ECB_PRINTK("%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) {
+		ckrm_task_lock(tsk->parent);
+		cls = tsk->parent->taskclass;
+		ckrm_core_grab(class_core(cls));
+		ckrm_task_unlock(tsk->parent);
+	}
+	if (!list_empty(&tsk->taskclass_link))
+		printk("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)
+{
+	ECB_PRINTK("%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)
+{
+	ECB_PRINTK("%p:%d:%s\n", current, current->pid, current->comm);
+	CE_CLASSIFY_TASK_PROTECT(CKRM_EVENT_UID, current);
+}
+
+static void cb_taskclass_gid(void)
+{
+	ECB_PRINTK("%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_SPEC(NEWTASK, cb_taskclass_newtask),
+	CKRM_EVENT_SPEC(EXEC, cb_taskclass_exec),
+	CKRM_EVENT_SPEC(FORK, cb_taskclass_fork),
+	CKRM_EVENT_SPEC(EXIT, cb_taskclass_exit),
+	CKRM_EVENT_SPEC(UID, cb_taskclass_uid),
+	CKRM_EVENT_SPEC(GID, cb_taskclass_gid),
+	{-1}
+};
+
+/***********************************************************************
+ *
+ * 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 
+ *
+ ***********************************************************************/
+
+DECLARE_MUTEX(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(&async_serializer);	// protect again race condition
+	TC_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(ckrm_task_class_t, 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 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;
+	}
+	TC_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(&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.typeID);
+	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)) {
+		// Invalid core
+		return (-EINVAL);
+	}
+	if (core == core->classtype->default_class) {
+		// reset the name tag
+		core->name = dflt_taskclass_name;
+		return 0;
+	}
+
+	TC_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.typeID);
+	ckrm_reclassify_class_tasks(taskcls);
+
+	ce_release(&CT_taskclass);
+
+	ckrm_release_core_class(core);	
+	// Hubertus .... could just drop the class .. error message
+	return 0;
+}
+
+void __init ckrm_meta_init_taskclass(void)
+{
+	printk("...... 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(&async_serializer);	// protect again race condition with reclassify_class
+	if (pid < 0) {
+		// do we want to treat this as process group .. TBD
+		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(ckrm_task_class_t,target);
+		rc = ckrm_forced_reclassify_pid(pid,cls);
+	}
+	up(&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);
+			printk("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) {
+				printk("list is CORRUPTED\n");
+				break;
+			}
+			if (tsk->taskclass != cls) {
+				const char *tclsname;
+				tclsname = (tsk->taskclass) ? 
+					class_core(tsk->taskclass)->name:"NULL";
+				printk("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;
+
+	printk("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";
+			printk("%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);
+
+	printk("End Analyze Error <%s> %d\n",
+	       class_core(tskcls)->name,
+	       atomic_read(&(class_core(tskcls)->refcnt)));
+}
+
+#endif
Index: linux-2.6.10-rc2/kernel/ckrm/Makefile
===================================================================
--- linux-2.6.10-rc2.orig/kernel/ckrm/Makefile	2004-11-19 20:43:43.000000000 -0800
+++ linux-2.6.10-rc2/kernel/ckrm/Makefile	2004-11-22 14:51:22.363138846 -0800
@@ -5,3 +5,4 @@
 ifeq ($(CONFIG_CKRM),y)
     obj-y = ckrm_events.o ckrm.o ckrmutils.o
 endif	
+obj-$(CONFIG_CKRM_TYPE_TASKCLASS)  += ckrm_tc.o
Index: linux-2.6.10-rc2/net/ipv4/tcp_ipv4.c
===================================================================
--- linux-2.6.10-rc2.orig/net/ipv4/tcp_ipv4.c	2004-11-14 17:27:18.000000000 -0800
+++ linux-2.6.10-rc2/net/ipv4/tcp_ipv4.c	2004-11-22 14:54:34.756658621 -0800
@@ -2653,6 +2653,7 @@
 EXPORT_SYMBOL(tcp_put_port);
 EXPORT_SYMBOL(tcp_unhash);
 EXPORT_SYMBOL(tcp_v4_conn_request);
+EXPORT_SYMBOL(tcp_v4_lookup_listener);
 EXPORT_SYMBOL(tcp_v4_connect);
 EXPORT_SYMBOL(tcp_v4_do_rcv);
 EXPORT_SYMBOL(tcp_v4_rebuild_header);

^ permalink raw reply	[flat|nested] 3+ messages in thread