Here's the new statctr patch (2.5.29) on top of kmalloc_percpu dynamic
allocator. This one passes GFP_ flags for statctr_init as suggested by
Andrew Morton and makes use of cpu_possible. Counters can be grouped into
one or multiple /proc files as per Rik's suggestion.
Here are the revised interfaces:
1. struct statctr_proc_entry
*create_statctr_proc_entry(struct proc_dir_entry *parent, const char *name);
To create a /proc file to group counters for automatic /proc reporting
2. free_statctr_proc_entry(struct statctr_proc_entry *)
To free up the proc entry
3. int statctr_init(statctr_t *stctr, unsigned long val,
struct statctr_proc_entry *pentry,
const char *ctrname, int flags)
Allocates memory to the counter , initialises it, and links the counter
with statctr_proc_entry for automatic /proc reporting. ctrname is the
counter label as it appears in /proc, flags are the GFP_ hints.
/proc reporting can be turned off if pentry is NULL.
4. statctr_cleanup(statctr_t *)
frees up counter memory and unlinks statctr_proc_entry association.
5. statctr_inc(statctr_t *) , statctr_dec(statctr_t *) ...... for fast
counter ops.
Rik does this suit you?
Thanks,
Kiran
diff -ruN -X dontdiff linux-2.5.29/fs/proc/proc_misc.c statctr-2.5.29-6/fs/proc/proc_misc.c
--- linux-2.5.29/fs/proc/proc_misc.c Sat Jul 27 08:28:29 2002
+++ statctr-2.5.29-6/fs/proc/proc_misc.c Tue Aug 6 17:05:06 2002
@@ -63,7 +63,7 @@
extern int get_ds1286_status(char *);
#endif
-static int proc_calc_metrics(char *page, char **start, off_t off,
+int proc_calc_metrics(char *page, char **start, off_t off,
int count, int *eof, int len)
{
if (len <= off+count) *eof = 1;
diff -ruN -X dontdiff linux-2.5.29/fs/proc/root.c statctr-2.5.29-6/fs/proc/root.c
--- linux-2.5.29/fs/proc/root.c Sat Jul 27 08:28:41 2002
+++ statctr-2.5.29-6/fs/proc/root.c Tue Aug 6 17:05:06 2002
@@ -19,6 +19,7 @@
#include <linux/smp_lock.h>
struct proc_dir_entry *proc_net, *proc_bus, *proc_root_fs, *proc_root_driver;
+struct proc_dir_entry *proc_statistics;
#ifdef CONFIG_SYSCTL
struct proc_dir_entry *proc_sys_root;
@@ -77,6 +78,7 @@
proc_rtas_init();
#endif
proc_bus = proc_mkdir("bus", 0);
+ proc_statistics = proc_mkdir("statistics", 0);
}
static struct dentry *proc_root_lookup(struct inode * dir, struct dentry * dentry)
diff -ruN -X dontdiff linux-2.5.29/include/linux/proc_fs.h statctr-2.5.29-6/include/linux/proc_fs.h
--- linux-2.5.29/include/linux/proc_fs.h Sat Jul 27 08:28:23 2002
+++ statctr-2.5.29-6/include/linux/proc_fs.h Tue Aug 6 17:05:06 2002
@@ -101,6 +101,7 @@
extern struct inode * proc_get_inode(struct super_block *, int, struct proc_dir_entry *);
extern int proc_match(int, const char *,struct proc_dir_entry *);
+extern int proc_calc_metrics(char *, char **, off_t, int, int *, int);
/*
* These are generic /proc routines that use the internal
diff -ruN -X dontdiff linux-2.5.29/include/linux/statctr.h statctr-2.5.29-6/include/linux/statctr.h
--- linux-2.5.29/include/linux/statctr.h Thu Jan 1 05:30:00 1970
+++ statctr-2.5.29-6/include/linux/statctr.h Wed Aug 7 09:25:53 2002
@@ -0,0 +1,254 @@
+/*
+ * Scalable Statistics Counters.
+ *
+ * Visit http://lse.sourceforge.net/counters for detailed explanation of
+ * Scalable Statistic Counters
+ *
+ * Copyright (c) IBM Corporation, 2001, 2002
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ * Author: Ravikiran Thirumalai <kiran@...>
+ *
+ * include/linux/statctr.h
+ *
+ */
+
+#ifndef _LINUX_STATCTR_H
+#define _LINUX_STATCTR_H
+
+#ifdef __KERNEL__
+
+#include <linux/config.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/proc_fs.h>
+
+struct statctr_proc_entry {
+ struct proc_dir_entry *parent;
+ char *procname;
+ struct list_head head;
+};
+
+typedef struct {
+#ifdef CONFIG_SMP
+ unsigned long *ctr;
+#else
+ unsigned long ctr;
+#endif
+#ifdef CONFIG_PROC_FS
+ char *name;
+ struct list_head pentrylist;
+#endif /* CONFIG_PROC_FS */
+} statctr_t;
+
+/* prototypes */
+extern int statctr_init(statctr_t *, unsigned long,
+ struct statctr_proc_entry *, const char *,int);
+extern void statctr_cleanup(statctr_t *);
+
+#ifdef CONFIG_PROC_FS
+extern struct proc_dir_entry *proc_statistics;
+extern struct statctr_proc_entry
+ *create_statctr_proc_entry(struct proc_dir_entry *, const char *);
+extern void free_statctr_proc_entry(struct statctr_proc_entry *);
+#else
+static inline struct statctr_proc_entry
+*create_statctr_proc_entry(struct proc_dir_entry *parent, const char *name)
+{
+ return(NULL);
+}
+static inline void free_statctr_proc_entry(struct statctr_proc_entry *pentry)
+{
+}
+#endif
+
+#ifdef CONFIG_SMP
+
+static inline int __statctr_init(statctr_t *stctr, int flags)
+{
+ stctr->ctr = kmalloc_percpu(sizeof(*(stctr->ctr)), flags);
+ if(!stctr->ctr)
+ return -1;
+ return 0;
+}
+
+static inline void __statctr_cleanup(statctr_t *stctr)
+{
+ kfree_percpu(stctr->ctr);
+}
+
+/**
+ * statctr_inc - Increment the statistics counter by one.
+ * @stctr: Statistics counter
+ *
+ * Increments the counter by one. Internally only the per-cpu counter is
+ * incremented.
+ */
+
+static inline void statctr_inc(statctr_t *stctr)
+{
+ (*this_cpu_ptr(stctr->ctr))++;
+}
+
+/**
+ * statctr_dec - Deccrement the statistics counter by one.
+ * @stctr: Statistics counter
+ *
+ * Decrements the counter by one. Internally only the per-cpu counter is
+ * incremented.
+ */
+
+static inline void statctr_dec(statctr_t *stctr)
+{
+ (*this_cpu_ptr(stctr->ctr))--;
+}
+
+/**
+ * statctr_set - Set the statistics counter to value passed.
+ * @stctr: Statistcs counter
+ * @val: Value to be set..
+ *
+ * Sets the statistics counter. If statctr_read() is invoked after a counter
+ * is set, return value of statctr_read shud reflect the value set.
+ */
+
+static inline void statctr_set(statctr_t *stctr, unsigned long val)
+{
+ int i;
+
+ for (i=0; i < NR_CPUS; i++) {
+ if(cpu_possible(i))
+ *per_cpu_ptr(stctr->ctr, i) = 0;
+ }
+ *this_cpu_ptr(stctr->ctr) = val;
+}
+
+/**
+ * statctr_read - Returns the counter value.
+ * @stctr: Statistics counter
+ *
+ * Reads all of the other per-cpu versions of this counter, consolidates them
+ * and returns to the caller.
+ */
+
+static inline unsigned long statctr_read(statctr_t *stctr)
+{
+ int i;
+ unsigned long res = 0;
+ for( i=0; i < NR_CPUS; i++ )
+ if(cpu_possible(i))
+ res += *per_cpu_ptr(stctr->ctr, i);
+ return res;
+}
+
+/**
+ * statctr_read_local - Returns the cpu local counter value.
+ * @stctr: Statistics counter
+ */
+
+static inline unsigned long statctr_read_local(statctr_t *stctr)
+{
+ return *this_cpu_ptr(stctr->ctr);
+}
+
+/**
+ * statctr_read_cpu - Returns the cpu counter value.
+ * @stctr: Statistics counter
+ */
+
+static inline unsigned long statctr_read_cpu(statctr_t *stctr, int cpu)
+{
+ return *per_cpu_ptr(stctr->ctr, cpu);
+}
+
+/**
+ * statctr_add - Adds the passed val to the counter value.
+ * @stctr: Statistics counter
+ * @val: Addend
+ *
+ */
+
+static inline void statctr_add(statctr_t *stctr, unsigned long val)
+{
+ *this_cpu_ptr(stctr->ctr) += val;
+}
+
+/**
+ * statctr_sub - Subtracts the passed val from the counter value.
+ * @stctr: Statistics counter
+ * @val: Subtrahend
+ *
+ */
+
+static inline void statctr_sub(statctr_t *stctr, unsigned long val)
+{
+ *this_cpu_ptr(stctr->ctr) -= val;
+}
+
+#else /* CONFIG_SMP */
+
+static inline int __statctr_init(statctr_t *stctr, int flags)
+{
+ return 0;
+}
+
+static inline void __statctr_cleanup(statctr_t *stctr) {}
+
+static inline void statctr_inc(statctr_t *stctr)
+{
+ (stctr->ctr)++;
+}
+
+static inline void statctr_dec(statctr_t *stctr)
+{
+ (stctr->ctr)--;
+}
+
+static inline unsigned long statctr_read(statctr_t *stctr)
+{
+ return(stctr->ctr);
+}
+
+static inline unsigned long statctr_read_local(statctr_t *stctr)
+{
+ return(stctr->ctr);
+}
+
+static inline unsigned long statctr_read_cpu(statctr_t *stctr, int cpu)
+{
+ return(stctr->ctr);
+}
+
+static inline void statctr_set(statctr_t *stctr, unsigned long val)
+{
+ stctr->ctr = val;
+}
+
+static inline void statctr_add(statctr_t *stctr, unsigned long val)
+{
+ stctr->ctr += val;
+}
+
+static inline void statctr_sub(statctr_t *stctr, unsigned long val)
+{
+ stctr->ctr -= val;
+}
+
+#endif /* CONFIG_SMP */
+
+#endif /* __KERNEL__ */
+
+#endif /* _LINUX_STATCTR_H */
diff -ruN -X dontdiff linux-2.5.29/kernel/Makefile statctr-2.5.29-6/kernel/Makefile
--- linux-2.5.29/kernel/Makefile Sat Jul 27 08:28:31 2002
+++ statctr-2.5.29-6/kernel/Makefile Tue Aug 6 17:05:06 2002
@@ -10,12 +10,12 @@
O_TARGET := kernel.o
export-objs = signal.o sys.o kmod.o context.o ksyms.o pm.o exec_domain.o \
- printk.o platform.o suspend.o
+ printk.o platform.o suspend.o statctr.o
obj-y = sched.o dma.o fork.o exec_domain.o panic.o printk.o \
module.o exit.o itimer.o time.o softirq.o resource.o \
sysctl.o capability.o ptrace.o timer.o user.o \
- signal.o sys.o kmod.o context.o futex.o platform.o
+ signal.o sys.o kmod.o context.o futex.o platform.o statctr.o
obj-$(CONFIG_SMP) += cpu.o
obj-$(CONFIG_UID16) += uid16.o
diff -ruN -X dontdiff linux-2.5.29/kernel/statctr.c statctr-2.5.29-6/kernel/statctr.c
--- linux-2.5.29/kernel/statctr.c Thu Jan 1 05:30:00 1970
+++ statctr-2.5.29-6/kernel/statctr.c Tue Aug 6 17:05:34 2002
@@ -0,0 +1,213 @@
+/*
+ * Scalable Statistics Counters.
+ *
+ * Visit http://lse.sourceforge.net/counters for detailed explanation of
+ * Scalable Statistic Counters
+ *
+ * Copyright (c) IBM Corporation, 2001, 2002.
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ * Author: Ravikiran Thirumalai <kiran@...>
+ *
+ * kernel/statctr.c
+ *
+ */
+
+#include <linux/statctr.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+
+#ifdef CONFIG_PROC_FS
+static int read_statctr_proc_entry(char *page, char **start,
+ off_t off, int count, int *eof, void *data)
+{
+ struct list_head *tmp;
+ int len = 0;
+ char *spc = " ";
+ struct statctr_proc_entry *pentry =
+ (struct statctr_proc_entry *) data;
+
+ list_for_each(tmp, &pentry->head) {
+ char *str;
+ statctr_t *stctr;
+ stctr = list_entry(tmp, statctr_t, pentrylist);
+ if(!stctr->name) {
+ str = spc;
+ }
+ else {
+ str = stctr->name;
+ }
+ len += sprintf(page+len,
+ "%s %ld\n", str, statctr_read(stctr));
+ }
+
+ return proc_calc_metrics(page, start, off, count, eof, len);
+}
+
+/**
+ * create_statctr_proc_entry - Creates and sets up a "statctr proc entry"
+ * @parent : proc_dir_entry under which @procname entry should appear.
+ * NULL is ok; but procname will be created under
+ * '/proc/statistics/' -- that is as /proc/statistics/$procname
+ * @procname: Name of the /proc file which the statctr pentry represents
+ *
+ * Memory to the statctr proc entry will be allocated by this method.
+ * This method registers the procname file under proc_dir_entry.
+ * Returns non zero on error.
+ */
+struct statctr_proc_entry
+ *create_statctr_proc_entry(struct proc_dir_entry *parent,
+ const char *procname)
+{
+ struct statctr_proc_entry *pentry = NULL;
+ struct proc_dir_entry *tmpentry, *tmpparent;
+
+ if(!procname)
+ return NULL;
+
+ if(!parent)
+ tmpparent = proc_statistics;
+ else
+ tmpparent = parent;
+
+ pentry = kmalloc(sizeof(*pentry), GFP_KERNEL);
+ if(!pentry)
+ return NULL;
+
+ tmpentry = create_proc_read_entry (procname, 0444, tmpparent,
+ read_statctr_proc_entry, pentry);
+ if(!tmpentry) {
+ kfree(pentry);
+ return NULL;
+ }
+
+ pentry->procname = kmalloc(strlen(procname) + 1, GFP_KERNEL);
+ if(!pentry->procname) {
+ remove_proc_entry(procname, tmpparent);
+ kfree(pentry);
+ return NULL;
+ }
+ memcpy(pentry->procname, procname, strlen(procname)+1);
+ pentry->parent = tmpparent;
+ INIT_LIST_HEAD(&pentry->head);
+
+ return pentry;
+}
+
+/**
+ * free_statctr_proc_entry - Perform cleanup functions on a statctr pentry
+ * @pentry: Pointer to struct statctr_proc_entry type;
+ * This method unregisters the proc entry associated with this @pentry and
+ * frees the memory pointed by it.
+ */
+void free_statctr_proc_entry(struct statctr_proc_entry *pentry)
+{
+ if(!list_empty(&pentry->head))
+ BUG();
+ remove_proc_entry(pentry->procname, pentry->parent);
+ kfree(pentry->procname);
+ kfree(pentry);
+}
+
+static int statctr_link_pentry(statctr_t *stctr,
+ struct statctr_proc_entry *pentry,
+ const char *ctrname,
+ int flags)
+{
+ stctr->name = NULL;
+ if(!pentry) {
+ INIT_LIST_HEAD(&stctr->pentrylist);
+ return 0;
+ }
+
+ if(ctrname) {
+ stctr->name = kmalloc(strlen(ctrname) + 1, flags);
+ if(!stctr->name)
+ return -1;
+ memcpy(stctr->name, ctrname, strlen(ctrname)+1);
+ }
+
+ list_add_tail(&stctr->pentrylist, &pentry->head);
+ return 0;
+}
+
+static void statctr_unlink_pentry(statctr_t *stctr)
+{
+ if(stctr->name)
+ kfree(stctr->name);
+ if(!list_empty(&stctr->pentrylist))
+ list_del(&stctr->pentrylist);
+}
+#else /* CONFIG_PROC_FS */
+#define statctr_link_pentry(stctr, pentry, ctrname, flags) \
+ ({do { } while (0); 0;})
+#define statctr_unlink_pentry(stctr) do { } while (0)
+#endif /* CONFIG_PROC_FS */
+
+/**
+ * statctr_init - Sets up the statistics counter
+ * @stctr : Pointer to statctr_t type; counter to be initialised
+ * @val : Initial value.
+ * @pentry : The struct statctr_proc_entry type which represents a
+ * /proc entry. This should have been created by using the
+ * create_statctr_proc_entry interface. Passing NULL turns
+ * off /proc association for the counter & @ctrname is ignored.
+ * @ctrname : This is the label of the counter in the /proc file
+ * indicated by @pentry. NULL is also fine; you just don't see
+ * a label against the counter value then.
+ * @flags : GFP_xx flags to be passed for kernel memory allocation.
+ *
+ * Allocates memory to a statistics counter. Returns 0 on successful
+ * allocation and non zero otherwise. Makes a /proc entry based on the
+ * pentry parameter. statctr_init s linking to a single statctr_proc_entry
+ * should be done either single threadedly or with your own serialization.
+ * There could have been a per pentry lock on the statctr_proc_entry, but
+ * then you would have no control over the order in which entries show up
+ * on /proc
+ */
+int statctr_init(statctr_t *stctr, unsigned long val,
+ struct statctr_proc_entry *pentry,
+ const char *ctrname,
+ int flags)
+{
+ if(__statctr_init(stctr, flags))
+ return -1;
+ if(statctr_link_pentry(stctr, pentry, ctrname, flags)) {
+ __statctr_cleanup(stctr);
+ return -1;
+ }
+ statctr_set(stctr, val);
+ return 0;
+}
+
+/**
+ * statctr_cleanup - Perform cleanup functions on a statctr counter
+ * @ctr: Pointer to statctr_t type;
+ */
+void statctr_cleanup(statctr_t *stctr)
+{
+ __statctr_cleanup(stctr);
+ statctr_unlink_pentry(stctr);
+}
+
+#ifdef CONFIG_PROC_FS
+EXPORT_SYMBOL(create_statctr_proc_entry);
+EXPORT_SYMBOL(free_statctr_proc_entry);
+#endif
+
+EXPORT_SYMBOL(statctr_init);
+EXPORT_SYMBOL(statctr_cleanup);
+
|