From: Mikael Pettersson <mikpe@csd.uu.se>
- core driver files and kernel changes
DESC
perfctr: remove bogus perfctr_sample_thread() calls
EDESC
From: Mikael Pettersson <mikpe@user.it.uu.se>
2.6.10-mm3 added perfctr_sample_thread() calls in
account_{user,system}_time(). I believe these to be bogus:
1. When they are called from update_process_times(), there
will be two perfctr_sample_thread()s per tick, one of
which is redundant.
2. s390's weird timer tick code calls both account_{user,system}_time()
directly, bypassing update_process_times(). In this case there
also be two perfctr_sample_thread()s per tick.
I believe the proper fix is to remove the new calls and, should s390 ever
get perfctr support, add _one_ perfctr_sample_thread() call in s390's
account_user_vtime().
The patch below removes the extraneous calls.
Signed-off-by: Mikael Pettersson <mikpe@csd.uu.se>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---
25-akpm/CREDITS | 1
25-akpm/MAINTAINERS | 6 +
25-akpm/drivers/Makefile | 1
25-akpm/drivers/perfctr/Kconfig | 45 ++++++++++
25-akpm/drivers/perfctr/Makefile | 16 +++
25-akpm/drivers/perfctr/cpumask.h | 24 +++++
25-akpm/drivers/perfctr/init.c | 97 +++++++++++++++++++++++
25-akpm/drivers/perfctr/version.h | 1
25-akpm/include/linux/perfctr.h | 158 ++++++++++++++++++++++++++++++++++++++
25-akpm/kernel/sched.c | 3
25-akpm/kernel/sys_ni.c | 6 +
25-akpm/kernel/timer.c | 2
kernel/sys.c | 0
13 files changed, 360 insertions(+)
diff -puN CREDITS~perfctr-core CREDITS
--- 25/CREDITS~perfctr-core 2005-03-20 16:57:00.000000000 -0800
+++ 25-akpm/CREDITS 2005-03-20 16:57:00.000000000 -0800
@@ -2624,6 +2624,7 @@ N: Mikael Pettersson
E: mikpe@csd.uu.se
W: http://www.csd.uu.se/~mikpe/
D: Miscellaneous fixes
+D: Performance-monitoring counters driver
N: Reed H. Petty
E: rhp@draper.net
diff -puN drivers/Makefile~perfctr-core drivers/Makefile
--- 25/drivers/Makefile~perfctr-core 2005-03-20 16:57:00.000000000 -0800
+++ 25-akpm/drivers/Makefile 2005-03-20 16:57:00.000000000 -0800
@@ -63,6 +63,7 @@ obj-$(CONFIG_MCA) += mca/
obj-$(CONFIG_EISA) += eisa/
obj-$(CONFIG_CPU_FREQ) += cpufreq/
obj-$(CONFIG_MMC) += mmc/
+obj-$(CONFIG_PERFCTR) += perfctr/
obj-$(CONFIG_INFINIBAND) += infiniband/
obj-$(CONFIG_BLK_DEV_SGIIOC4) += sn/
obj-y += firmware/
diff -puN /dev/null drivers/perfctr/cpumask.h
--- /dev/null 2003-09-15 06:40:47.000000000 -0700
+++ 25-akpm/drivers/perfctr/cpumask.h 2005-03-20 16:57:00.000000000 -0800
@@ -0,0 +1,24 @@
+/* $Id: cpumask.h,v 1.7 2004/05/12 19:59:01 mikpe Exp $
+ * Performance-monitoring counters driver.
+ * Partial simulation of cpumask_t on non-cpumask_t kernels.
+ * Extension to allow inspecting a cpumask_t as array of ulong.
+ * Appropriate definition of perfctr_cpus_forbidden_mask.
+ *
+ * Copyright (C) 2003-2004 Mikael Pettersson
+ */
+
+#ifdef CPU_ARRAY_SIZE
+#define PERFCTR_CPUMASK_NRLONGS CPU_ARRAY_SIZE
+#else
+#define PERFCTR_CPUMASK_NRLONGS 1
+#endif
+
+/* `perfctr_cpus_forbidden_mask' used to be defined in <asm/perfctr.h>,
+ but cpumask_t compatibility issues forced it to be moved here. */
+#if PERFCTR_CPUS_FORBIDDEN_MASK_NEEDED
+extern cpumask_t perfctr_cpus_forbidden_mask;
+#define perfctr_cpu_is_forbidden(cpu) cpu_isset((cpu), perfctr_cpus_forbidden_mask)
+#else
+#define perfctr_cpus_forbidden_mask CPU_MASK_NONE
+#define perfctr_cpu_is_forbidden(cpu) 0 /* cpu_isset() needs an lvalue :-( */
+#endif
diff -puN /dev/null drivers/perfctr/init.c
--- /dev/null 2003-09-15 06:40:47.000000000 -0700
+++ 25-akpm/drivers/perfctr/init.c 2005-03-20 16:57:00.000000000 -0800
@@ -0,0 +1,97 @@
+/* $Id: init.c,v 1.76 2004/05/31 18:18:55 mikpe Exp $
+ * Performance-monitoring counters driver.
+ * Top-level initialisation code.
+ *
+ * Copyright (C) 1999-2004 Mikael Pettersson
+ */
+#include <linux/config.h>
+#include <linux/fs.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/perfctr.h>
+
+#include <asm/uaccess.h>
+
+#include "cpumask.h"
+#include "virtual.h"
+#include "version.h"
+
+struct perfctr_info perfctr_info = {
+ .abi_version = PERFCTR_ABI_VERSION,
+ .driver_version = VERSION,
+};
+
+char *perfctr_cpu_name __initdata;
+
+static int cpus_copy_to_user(const cpumask_t *cpus, struct perfctr_cpu_mask *argp)
+{
+ const unsigned int k_nrwords = PERFCTR_CPUMASK_NRLONGS*(sizeof(long)/sizeof(int));
+ unsigned int u_nrwords;
+ unsigned int ui, ki, j;
+
+ if (get_user(u_nrwords, &argp->nrwords))
+ return -EFAULT;
+ if (put_user(k_nrwords, &argp->nrwords))
+ return -EFAULT;
+ if (u_nrwords < k_nrwords)
+ return -EOVERFLOW;
+ for(ui = 0, ki = 0; ki < PERFCTR_CPUMASK_NRLONGS; ++ki) {
+ unsigned long mask = cpus_addr(*cpus)[ki];
+ for(j = 0; j < sizeof(long)/sizeof(int); ++j) {
+ if (put_user((unsigned int)mask, &argp->mask[ui]))
+ return -EFAULT;
+ ++ui;
+ mask = (mask >> (8*sizeof(int)-1)) >> 1;
+ }
+ }
+ return 0;
+}
+
+asmlinkage long sys_perfctr_info(struct perfctr_info *infop,
+ struct perfctr_cpu_mask *cpusp,
+ struct perfctr_cpu_mask *forbiddenp)
+{
+ if (infop && copy_to_user(infop, &perfctr_info, sizeof perfctr_info))
+ return -EFAULT;
+ if (cpusp) {
+ cpumask_t cpus = cpu_online_map;
+ int err = cpus_copy_to_user(&cpus, cpusp);
+ if (err)
+ return err;
+ }
+ if (forbiddenp) {
+ cpumask_t cpus = perfctr_cpus_forbidden_mask;
+ int err = cpus_copy_to_user(&cpus, forbiddenp);
+ if (err)
+ return err;
+ }
+ return 0;
+}
+
+int __init perfctr_init(void)
+{
+ int err;
+
+ err = perfctr_cpu_init();
+ if (err) {
+ printk(KERN_INFO "perfctr: not supported by this processor\n");
+ return err;
+ }
+ err = vperfctr_init();
+ if (err)
+ return err;
+ printk(KERN_INFO "perfctr: driver %s, cpu type %s at %u kHz\n",
+ perfctr_info.driver_version,
+ perfctr_cpu_name,
+ perfctr_info.cpu_khz);
+ return 0;
+}
+
+void __exit perfctr_exit(void)
+{
+ vperfctr_exit();
+ perfctr_cpu_exit();
+}
+
+module_init(perfctr_init)
+module_exit(perfctr_exit)
diff -puN /dev/null drivers/perfctr/Kconfig
--- /dev/null 2003-09-15 06:40:47.000000000 -0700
+++ 25-akpm/drivers/perfctr/Kconfig 2005-03-20 16:57:00.000000000 -0800
@@ -0,0 +1,45 @@
+# $Id: Kconfig,v 1.10 2004/05/24 11:00:55 mikpe Exp $
+# Performance-monitoring counters driver configuration
+#
+
+menu "Performance-monitoring counters support"
+
+config PERFCTR
+ bool "Performance monitoring counters support"
+ help
+ This driver provides access to the performance-monitoring counter
+ registers available in some (but not all) modern processors.
+ These special-purpose registers can be programmed to count low-level
+ performance-related events which occur during program execution,
+ such as cache misses, pipeline stalls, etc.
+
+ You can safely say Y here, even if you intend to run the kernel
+ on a processor without performance-monitoring counters.
+
+config PERFCTR_INIT_TESTS
+ bool "Init-time hardware tests"
+ depends on PERFCTR
+ help
+ This option makes the driver perform additional hardware tests
+ during initialisation, and log their results in the kernel's
+ message buffer. For most supported processors, these tests simply
+ measure the runtime overheads of performance counter operations.
+
+ If you have a less well-known processor (one not listed in the
+ etc/costs/ directory in the user-space package), you should enable
+ this option and email the results to the perfctr developers.
+
+ If unsure, say N.
+
+config PERFCTR_VIRTUAL
+ bool "Virtual performance counters support"
+ depends on PERFCTR
+ help
+ The processor's performance-monitoring counters are special-purpose
+ global registers. This option adds support for virtual per-process
+ performance-monitoring counters which only run when the process
+ to which they belong is executing. This improves the accuracy of
+ performance measurements by reducing "noise" from other processes.
+
+ Say Y.
+endmenu
diff -puN /dev/null drivers/perfctr/Makefile
--- /dev/null 2003-09-15 06:40:47.000000000 -0700
+++ 25-akpm/drivers/perfctr/Makefile 2005-03-20 16:57:00.000000000 -0800
@@ -0,0 +1,16 @@
+# $Id: Makefile,v 1.26 2004/05/30 23:02:14 mikpe Exp $
+# Makefile for the Performance-monitoring counters driver.
+
+# This also covers x86_64.
+perfctr-objs-$(CONFIG_X86) := x86.o
+tests-objs-$(CONFIG_X86) := x86_tests.o
+
+perfctr-objs-$(CONFIG_PPC32) := ppc.o
+tests-objs-$(CONFIG_PPC32) := ppc_tests.o
+
+perfctr-objs-y += init.o
+perfctr-objs-$(CONFIG_PERFCTR_INIT_TESTS) += $(tests-objs-y)
+perfctr-objs-$(CONFIG_PERFCTR_VIRTUAL) += virtual.o
+
+perfctr-objs := $(perfctr-objs-y)
+obj-$(CONFIG_PERFCTR) := perfctr.o
diff -puN /dev/null drivers/perfctr/version.h
--- /dev/null 2003-09-15 06:40:47.000000000 -0700
+++ 25-akpm/drivers/perfctr/version.h 2005-03-20 16:57:00.000000000 -0800
@@ -0,0 +1 @@
+#define VERSION "2.7.3"
diff -puN /dev/null include/linux/perfctr.h
--- /dev/null 2003-09-15 06:40:47.000000000 -0700
+++ 25-akpm/include/linux/perfctr.h 2005-03-20 16:57:00.000000000 -0800
@@ -0,0 +1,158 @@
+/* $Id: perfctr.h,v 1.78 2004/05/31 20:45:51 mikpe Exp $
+ * Performance-Monitoring Counters driver
+ *
+ * Copyright (C) 1999-2004 Mikael Pettersson
+ */
+#ifndef _LINUX_PERFCTR_H
+#define _LINUX_PERFCTR_H
+
+#ifdef CONFIG_PERFCTR /* don't break archs without <asm/perfctr.h> */
+
+#include <asm/perfctr.h>
+
+struct perfctr_info {
+ unsigned int abi_version;
+ char driver_version[32];
+ unsigned int cpu_type;
+ unsigned int cpu_features;
+ unsigned int cpu_khz;
+ unsigned int tsc_to_cpu_mult;
+ unsigned int _reserved2;
+ unsigned int _reserved3;
+ unsigned int _reserved4;
+};
+
+struct perfctr_cpu_mask {
+ unsigned int nrwords;
+ unsigned int mask[1]; /* actually 'nrwords' */
+};
+
+/* abi_version values: Lower 16 bits contain the CPU data version, upper
+ 16 bits contain the API version. Each half has a major version in its
+ upper 8 bits, and a minor version in its lower 8 bits. */
+#define PERFCTR_API_VERSION 0x0600 /* 6.0 */
+#define PERFCTR_ABI_VERSION ((PERFCTR_API_VERSION<<16)|PERFCTR_CPU_VERSION)
+
+/* cpu_features flag bits */
+#define PERFCTR_FEATURE_RDPMC 0x01
+#define PERFCTR_FEATURE_RDTSC 0x02
+#define PERFCTR_FEATURE_PCINT 0x04
+
+/* user's view of mmap:ed virtual perfctr */
+struct vperfctr_state {
+ struct perfctr_cpu_state cpu_state;
+};
+
+/* virtual perfctr control object */
+struct vperfctr_control {
+ int si_signo;
+ struct perfctr_cpu_control cpu_control;
+ unsigned int preserve;
+ unsigned int _reserved1;
+ unsigned int _reserved2;
+ unsigned int _reserved3;
+ unsigned int _reserved4;
+};
+
+#else
+struct perfctr_info;
+struct perfctr_cpu_mask;
+struct perfctr_sum_ctrs;
+struct vperfctr_control;
+#endif /* CONFIG_PERFCTR */
+
+#ifdef __KERNEL__
+
+/*
+ * The perfctr system calls.
+ */
+asmlinkage long sys_perfctr_info(struct perfctr_info*, struct perfctr_cpu_mask*, struct perfctr_cpu_mask*);
+asmlinkage long sys_vperfctr_open(int tid, int creat);
+asmlinkage long sys_vperfctr_control(int fd, const struct vperfctr_control*);
+asmlinkage long sys_vperfctr_unlink(int fd);
+asmlinkage long sys_vperfctr_iresume(int fd);
+asmlinkage long sys_vperfctr_read(int fd,
+ struct perfctr_sum_ctrs*,
+ struct vperfctr_control*);
+
+extern struct perfctr_info perfctr_info;
+
+#ifdef CONFIG_PERFCTR_VIRTUAL
+
+/*
+ * Virtual per-process performance-monitoring counters.
+ */
+struct vperfctr; /* opaque */
+
+/* process management operations */
+extern struct vperfctr *__vperfctr_copy(struct vperfctr*);
+extern void __vperfctr_exit(struct vperfctr*);
+extern void __vperfctr_suspend(struct vperfctr*);
+extern void __vperfctr_resume(struct vperfctr*);
+extern void __vperfctr_sample(struct vperfctr*);
+extern void __vperfctr_set_cpus_allowed(struct task_struct*, struct vperfctr*, cpumask_t);
+
+static inline void perfctr_copy_thread(struct thread_struct *thread)
+{
+ thread->perfctr = NULL;
+}
+
+static inline void perfctr_exit_thread(struct thread_struct *thread)
+{
+ struct vperfctr *perfctr;
+ perfctr = thread->perfctr;
+ if (perfctr)
+ __vperfctr_exit(perfctr);
+}
+
+static inline void perfctr_suspend_thread(struct thread_struct *prev)
+{
+ struct vperfctr *perfctr;
+ perfctr = prev->perfctr;
+ if (perfctr)
+ __vperfctr_suspend(perfctr);
+}
+
+static inline void perfctr_resume_thread(struct thread_struct *next)
+{
+ struct vperfctr *perfctr;
+ perfctr = next->perfctr;
+ if (perfctr)
+ __vperfctr_resume(perfctr);
+}
+
+static inline void perfctr_sample_thread(struct thread_struct *thread)
+{
+ struct vperfctr *perfctr;
+ perfctr = thread->perfctr;
+ if (perfctr)
+ __vperfctr_sample(perfctr);
+}
+
+static inline void perfctr_set_cpus_allowed(struct task_struct *p, cpumask_t new_mask)
+{
+#if PERFCTR_CPUS_FORBIDDEN_MASK_NEEDED
+ struct vperfctr *perfctr;
+
+ task_lock(p);
+ perfctr = p->thread.perfctr;
+ if (perfctr)
+ __vperfctr_set_cpus_allowed(p, perfctr, new_mask);
+ task_unlock(p);
+#endif
+}
+
+#else /* !CONFIG_PERFCTR_VIRTUAL */
+
+static inline void perfctr_copy_thread(struct thread_struct *t) { }
+static inline void perfctr_exit_thread(struct thread_struct *t) { }
+static inline void perfctr_suspend_thread(struct thread_struct *t) { }
+static inline void perfctr_resume_thread(struct thread_struct *t) { }
+static inline void perfctr_sample_thread(struct thread_struct *t) { }
+static inline void perfctr_set_cpus_allowed(struct task_struct *p, cpumask_t m) { }
+
+#endif /* CONFIG_PERFCTR_VIRTUAL */
+
+#endif /* __KERNEL__ */
+
+#endif /* _LINUX_PERFCTR_H */
diff -puN kernel/sched.c~perfctr-core kernel/sched.c
--- 25/kernel/sched.c~perfctr-core 2005-03-20 16:57:00.000000000 -0800
+++ 25-akpm/kernel/sched.c 2005-03-20 16:57:00.000000000 -0800
@@ -42,6 +42,7 @@
#include <linux/cpu.h>
#include <linux/cpuset.h>
#include <linux/percpu.h>
+#include <linux/perfctr.h>
#include <linux/kthread.h>
#include <linux/seq_file.h>
#include <linux/syscalls.h>
@@ -4078,6 +4079,8 @@ int set_cpus_allowed(task_t *p, cpumask_
migration_req_t req;
runqueue_t *rq;
+ perfctr_set_cpus_allowed(p, new_mask);
+
rq = task_rq_lock(p, &flags);
if (!cpus_intersects(new_mask, cpu_online_map)) {
ret = -EINVAL;
diff -puN kernel/sys.c~perfctr-core kernel/sys.c
diff -puN kernel/timer.c~perfctr-core kernel/timer.c
--- 25/kernel/timer.c~perfctr-core 2005-03-20 16:57:00.000000000 -0800
+++ 25-akpm/kernel/timer.c 2005-03-20 16:57:00.000000000 -0800
@@ -32,6 +32,7 @@
#include <linux/jiffies.h>
#include <linux/posix-timers.h>
#include <linux/cpu.h>
+#include <linux/perfctr.h>
#include <linux/syscalls.h>
#include <asm/uaccess.h>
@@ -843,6 +844,7 @@ void update_process_times(int user_tick)
account_user_time(p, jiffies_to_cputime(1));
else
account_system_time(p, HARDIRQ_OFFSET, jiffies_to_cputime(1));
+ perfctr_sample_thread(&p->thread);
run_local_timers();
if (rcu_pending(cpu))
rcu_check_callbacks(cpu, user_tick);
diff -puN MAINTAINERS~perfctr-core MAINTAINERS
--- 25/MAINTAINERS~perfctr-core 2005-03-20 16:57:00.000000000 -0800
+++ 25-akpm/MAINTAINERS 2005-03-20 16:57:00.000000000 -0800
@@ -1816,6 +1816,12 @@ M: george@mvista.com
L: linux-net@vger.kernel.org
S: Supported
+PERFORMANCE-MONITORING COUNTERS DRIVER
+P: Mikael Pettersson
+M: mikpe@csd.uu.se
+W: http://www.csd.uu.se/~mikpe/linux/perfctr/
+S: Maintained
+
PNP SUPPORT
P: Adam Belay
M: ambx1@neo.rr.com
diff -puN kernel/sys_ni.c~perfctr-core kernel/sys_ni.c
--- 25/kernel/sys_ni.c~perfctr-core 2005-03-20 16:57:00.000000000 -0800
+++ 25-akpm/kernel/sys_ni.c 2005-03-20 16:57:00.000000000 -0800
@@ -65,6 +65,12 @@ cond_syscall(compat_sys_mq_timedsend);
cond_syscall(compat_sys_mq_timedreceive);
cond_syscall(compat_sys_mq_notify);
cond_syscall(compat_sys_mq_getsetattr);
+cond_syscall(sys_perfctr_info);
+cond_syscall(sys_vperfctr_open);
+cond_syscall(sys_vperfctr_control);
+cond_syscall(sys_vperfctr_unlink);
+cond_syscall(sys_vperfctr_iresume);
+cond_syscall(sys_vperfctr_read);
cond_syscall(sys_mbind);
cond_syscall(sys_get_mempolicy);
cond_syscall(sys_set_mempolicy);
_