[PATCH 2/3] Trec driver.

From: Wink Saville
Date: Sat Mar 24 2007 - 20:00:16 EST

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This is the Trec driver, Makefile, header files.
Enable trec in Kernel hacking configuration menu.

Signed-off-by: Wink Saville <wink@xxxxxxxxxxx>
---
drivers/Makefile | 1 +
drivers/trec/Makefile | 5 +
drivers/trec/trec.c | 404 ++++++++++++++++++++++++++++++++++++++++++++
include/asm-generic/trec.h | 17 ++
include/asm-i386/trec.h | 33 ++++
include/asm-x86_64/trec.h | 13 ++
include/linux/trec.h | 75 ++++++++
lib/Kconfig.debug | 7 +
8 files changed, 555 insertions(+), 0 deletions(-)
create mode 100644 drivers/trec/Makefile
create mode 100644 drivers/trec/trec.c
create mode 100644 include/asm-generic/trec.h
create mode 100644 include/asm-i386/trec.h
create mode 100644 include/asm-x86_64/trec.h
create mode 100644 include/linux/trec.h

diff --git a/drivers/Makefile b/drivers/Makefile
index 3a718f5..01724c0 100644
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -81,3 +81,4 @@ obj-$(CONFIG_GENERIC_TIME) += clocksource/
obj-$(CONFIG_DMA_ENGINE) += dma/
obj-$(CONFIG_HID) += hid/
obj-$(CONFIG_PPC_PS3) += ps3/
+obj-$(CONFIG_TREC) += trec/
diff --git a/drivers/trec/Makefile b/drivers/trec/Makefile
new file mode 100644
index 0000000..d930b4d
--- /dev/null
+++ b/drivers/trec/Makefile
@@ -0,0 +1,5 @@
+#
+# Makefile for Trace records.
+#
+
+obj-$(CONFIG_TREC) += trec.o
diff --git a/drivers/trec/trec.c b/drivers/trec/trec.c
new file mode 100644
index 0000000..0b04b71
--- /dev/null
+++ b/drivers/trec/trec.c
@@ -0,0 +1,404 @@
+/*
+ * Copyright (C) 2007 Saville Software, Inc.
+ *
+ * This code may be used for any purpose whatsoever,
+ * but no warranty of any kind is provided.
+ */
+
+#include <linux/device.h>
+#include <linux/fs.h>
+#include <linux/cdev.h>
+#include <linux/smp.h>
+#include <linux/kallsyms.h>
+#include <linux/sysrq.h>
+#include <linux/trec.h>
+
+#include <asm/trec.h>
+
+#define TREC_DEBUG
+#ifdef TREC_DEBUG
+#define DPK(fmt, args...) printk(KERN_ERR "trec " fmt, ## args)
+#else
+#define DPK(fmt, args...)
+#endif
+
+struct trec_dev_struct
+{
+ struct cdev cdev; /* Character device structure */
+};
+
+MODULE_AUTHOR("Wink Saville");
+MODULE_LICENSE("Dual BSD/GPL");
+
+/*
+ * Module parameters
+ */
+int major = 240; /* 240 a "local/expermental" device number for the moment */
+int minor = 1;
+
+module_param(major, int, S_IRUGO);
+module_param(minor, int, S_IRUGO);
+
+/*
+ * Forward declarations
+ */
+static int trec_open(struct inode *inode, struct file *file);
+static int trec_release(struct inode *inode, struct file *file);
+
+/*
+ * File operations
+ */
+struct file_operations trec_f_ops = {
+ .owner = THIS_MODULE,
+ .open = trec_open,
+ .release = trec_release,
+};
+
+struct trec_struct {
+ uint64_t tsc;
+ unsigned long pc;
+ unsigned long tsk;
+ unsigned int pid;
+ unsigned long v1;
+ unsigned long v2;
+};
+
+/*
+ * Change trec_buffer_struct.data to be a pointer to a PAGE in the future
+ */
+#define TREC_DATA_SIZE 0x200
+struct trec_buffer_struct {
+ struct trec_buffer_struct * next;
+ struct trec_struct * cur;
+ struct trec_struct * end;
+ struct trec_struct data[TREC_DATA_SIZE];
+};
+
+/*
+ * Number of buffers must be a multiple of two so we can
+ * snapshot the buffers and the minimum should be 4.
+ */
+#define TREC_COUNT 2
+struct trec_buffer_struct trec_buffers[2][TREC_COUNT];
+int trec_idx = 0;
+spinlock_t trec_lock = SPIN_LOCK_UNLOCKED;
+
+struct trec_buffer_struct * trec_buffer_cur = NULL;
+struct trec_buffer_struct * trec_buffer_snapshot = NULL;
+
+struct trec_dev_struct trec_dev;
+
+/**
+ * Print an address symbol if available to the buffer
+ * this is from traps.c
+ */
+static int snprint_address(char *b, int bsize, unsigned long address)
+{
+#ifdef CONFIG_KALLSYMS
+ unsigned long offset = 0, symsize;
+ const char *symname;
+ char *modname;
+ char *delim = ":";
+ int n;
+ char namebuf[128];
+
+ symname = kallsyms_lookup(address, &symsize, &offset, &modname, namebuf);
+ if (!symname) {
+ n = 0;
+ } else {
+ if (!modname)
+ modname = delim = "";
+ n = snprintf(b, bsize, "0x%016lx %s%s%s%s+0x%lx/0x%lx",
+ address, delim, modname, delim, symname, offset, symsize);
+ }
+ return n;
+#else
+ return snprintf(b, bsize, "0x%016lx", address);
+#endif
+}
+
+/*
+ * Initialize the trec buffers
+ */
+void trec_init(void)
+{
+ int i;
+ int j;
+
+ DPK("trec: trec_init E\n");
+
+ for (i = 0; i < 2; i++) {
+ for (j = 0; j < TREC_COUNT; j++) {
+ struct trec_buffer_struct *trec = &trec_buffers[i][j];
+
+ trec->next = &trec_buffers[i][(j+1) % TREC_COUNT];
+ trec->cur = &trec->data[0];
+ trec->end = &trec->data[TREC_DATA_SIZE];
+ memset(trec->cur, 0, sizeof(trec->data));
+ }
+ }
+
+ trec_idx = 0;
+ trec_buffer_cur = &trec_buffers[trec_idx][0];
+ trec_buffer_snapshot = NULL;
+
+ DPK("trec: trec_init X\n");
+}
+EXPORT_SYMBOL(trec_init);
+
+/*
+ * Write a trec entry
+ */
+void trec_write(unsigned long pc, int pid, unsigned long v1, unsigned long v2)
+{
+ struct trec_struct *trec;
+ int flags;
+
+ spin_lock_irqsave(&trec_lock, flags);
+ trec = trec_buffer_cur->cur;
+ trec_buffer_cur->cur += 1;
+ if (trec_buffer_cur->cur >= trec_buffer_cur->end) {
+ trec_buffer_cur = trec_buffer_cur->next;
+ trec_buffer_cur->cur = &trec_buffer_cur->data[0];
+ }
+ spin_unlock_irqrestore(&trec_lock, flags);
+
+ trec->tsc = rd_tsc();
+ trec->pc = pc;
+ trec->pid = pid;
+ trec->tsk = (unsigned long)current;
+ trec->v1 = v1;
+ trec->v2 = v2;
+}
+EXPORT_SYMBOL(trec_write);
+
+/*
+ * Snapshot the current trecs
+ */
+void trec_snapshot(void)
+{
+ int flags;
+
+ spin_lock_irqsave(&trec_lock, flags);
+ trec_buffer_snapshot = trec_buffer_cur;
+ trec_idx = trec_idx ^ 1;
+ trec_buffer_cur = &trec_buffers[trec_idx][0];
+ spin_unlock_irqrestore(&trec_lock, flags);
+}
+EXPORT_SYMBOL(trec_snapshot);
+
+/*
+ * trec_print
+ */
+void trec_print_snapshot(void)
+{
+ int i;
+ struct trec_buffer_struct *cur_buffer;
+
+ if (!trec_buffer_snapshot)
+ trec_snapshot();
+
+ cur_buffer = trec_buffer_snapshot->next;
+ for (i = 0; i < TREC_COUNT; i++) {
+ struct trec_struct *cur;
+
+ for (cur = &cur_buffer->data[0];
+ cur < cur_buffer->cur;
+ cur += 1) {
+ char b[256];
+ int n;
+
+ n = snprintf(b, sizeof(b), KERN_ERR "t=%20llu pid=%5u tsk=%p v1=%p v2=%p ",
+ cur->tsc, cur->pid, (void *)cur->tsk, (void *)cur->v1, (void *)cur->v2);
+ n += snprint_address(b+n, sizeof(b)-n, cur->pc);
+ printk("%s\n", b);
+ }
+ cur_buffer = cur_buffer->next;
+ }
+}
+EXPORT_SYMBOL(trec_print_snapshot);
+
+/*
+ * Sysrq support for trec's
+ */
+#ifdef CONFIG_MAGIC_SYSRQ
+/*
+ * trec print snapshot handler for sysrq
+ */
+static void sysrq_handle_trec_print_snapshot(int key, struct tty_struct *tty)
+{
+ trec_print_snapshot();
+}
+
+/*
+ * trec snapshot handler for sysrq
+ */
+static void sysrq_handle_trec_snapshot(int key, struct tty_struct *tty)
+{
+ trec_snapshot();
+}
+
+static struct sysrq_key_op sysrq_trec_snapshot_op =
+{
+ .handler = sysrq_handle_trec_snapshot,
+ .help_msg = "Trec snapshot(Y)",
+ .action_msg = "Trec snapshot",
+};
+
+static struct sysrq_key_op sysrq_trec_print_snapshot_op =
+{
+ .handler = sysrq_handle_trec_print_snapshot,
+ .help_msg = "Print current trec snapshot",
+ .action_msg = "Trec print snapshot(Z)",
+};
+
+/*
+ * Initilize trec sysrq support
+ */
+static int __init setup_trec_sysrq(void)
+{
+ DPK("setup_trec_sysrq y=trec_snapshot z=trec_print_snapshot\n");
+ register_sysrq_key('y', &sysrq_trec_snapshot_op);
+ register_sysrq_key('z', &sysrq_trec_print_snapshot_op);
+ return 0;
+}
+__initcall(setup_trec_sysrq);
+#endif /* CONFIG_MAGIC_SYSRQ */
+
+/*
+ * Open
+ */
+static int trec_open(struct inode *inode, struct file *file)
+{
+ int result = 0;
+ struct trec_dev_struct *dev;
+
+ DPK("trec_open: E\n");
+
+ dev = container_of(inode->i_cdev, struct trec_dev_struct, cdev);
+ file->private_data = (void *)dev;
+
+ DPK("trec_open: X result=%d\n", result);
+ return result;
+}
+
+/*
+ * Release/Close
+ */
+static int trec_release(struct inode *inode, struct file *file)
+{
+ int result = 0;
+
+ DPK("trec_release: E\n");
+
+ DPK("trec_release: X result=%d\n", result);
+ return result;
+}
+
+/*
+ * Init routine for the trec device
+ */
+static int __init trec_device_init(void)
+{
+ int result;
+ dev_t dev_number = 0;
+ static struct class *trec_class;
+
+ DPK("trec_device_init: E\n");
+
+ if (major) {
+ dev_number = MKDEV(major, minor);
+ result = register_chrdev_region(dev_number, 1, "trec");
+ DPK("trec_device_init: static major result=%d\n", result);
+ } else {
+ result = alloc_chrdev_region(&dev_number, minor, 1, "trec");
+ major = MAJOR(dev_number);
+ DPK("trec_device_init: dynamic major result=%d\n", result);
+ }
+
+ if (result < 0) {
+ printk(KERN_WARNING "trec: can't get major %d\n", major);
+ goto err;
+ }
+
+ cdev_init(&trec_dev.cdev, &trec_f_ops);
+ trec_dev.cdev.owner = THIS_MODULE;
+ trec_dev.cdev.ops = &trec_f_ops;
+
+ result = cdev_add(&trec_dev.cdev, dev_number, 1);
+ if (result)
+ {
+ DPK("trec_device_init: cdev_add failed\n");
+ goto err;
+ }
+
+ /*
+ * Make a trec class and create the device
+ */
+ trec_class = class_create(THIS_MODULE, "trec");
+ class_device_create(trec_class, NULL, dev_number, NULL, "trec");
+
+ /*
+ * If the trec buffers have not been initialized do so
+ */
+ if (trec_buffer_cur == NULL) {
+ trec_init();
+ }
+
+ /*
+ * Test macros
+ */
+ TREC(1, 2);
+ TRECC(1, 3, 4);
+ TRECC0(1);
+ TRECC1(1, 5);
+ TRECC2(1, 6, 7);
+
+ TREC0();
+ TREC1(8);
+ TREC2(9, 10);
+
+#undef TREC_ENABLED
+#define TREC_ENABLED 0
+ /*
+ * Should not be in the trec buffer
+ */
+ TREC(1, 11);
+ TRECC(1, 12, 13);
+ TRECC0(1);
+ TRECC1(1, 14);
+ TRECC2(1, 15, 16);
+
+ TREC0();
+ TREC1(17);
+ TREC2(18, 19);
+#undef TREC_ENABLED
+#define TREC_ENABLED 1
+
+ result = 0;
+ goto out;
+
+err:
+ unregister_chrdev_region(dev_number, 1);
+out:
+ DPK("trec_device_init: X result=%d major=%d minor=%d\n", result, major, minor);
+ TREC_RETV(result);
+}
+
+/*
+ * Exit routine for trec device
+ */
+static void __exit trec_device_exit(void)
+{
+ dev_t dev_number = MKDEV(major, minor);
+
+ DPK("trec_device_exit: E\n");
+
+ unregister_chrdev_region(dev_number, 1);
+
+ DPK("trec_device_exit: X\n");
+}
+
+module_init(trec_device_init);
+module_exit(trec_device_exit);
+
diff --git a/include/asm-generic/trec.h b/include/asm-generic/trec.h
new file mode 100644
index 0000000..4d8dffb
--- /dev/null
+++ b/include/asm-generic/trec.h
@@ -0,0 +1,17 @@
+/*
+ * Copyright (C) 2007 Saville Software, Inc.
+ *
+ * This code may be used for any purpose whatsoever, but
+ * no warranty of any kind is provided.
+ */
+
+#ifndef _ASM_GENERIC_TREC_H
+#define _ASM_GENERIC_TREC_H
+
+#ifndef __ASSEMBLY__
+
+#define rd_tsc() (0)
+
+#endif /* !__ASSEMBLY__ */
+
+#endif /* _ASM_GENERIC_TREC_H */
diff --git a/include/asm-i386/trec.h b/include/asm-i386/trec.h
new file mode 100644
index 0000000..1de4dc6
--- /dev/null
+++ b/include/asm-i386/trec.h
@@ -0,0 +1,33 @@
+/*
+ * Copyright (C) 2007 Saville Software, Inc.
+ *
+ * This code may be used for any purpose whatsoever, but
+ * no warranty of any kind is provided.
+ */
+
+#ifndef _ASM_I386_TREC_H
+#define _ASM_I386_TREC_H
+
+#ifndef __ASSEMBLY__
+
+#if CONFIG_X86_TSC
+#include <asm/msr.h>
+
+/*
+ * read x86 time stamp counter.
+ */
+static uint64_t inline rd_tsc(void)
+{
+ volatile uint64_t value;
+
+ rdtscll(value);
+
+ return value;
+}
+#else
+ #define rd_tsc() (0)
+#endif /* CONFIG_X86_TSC */
+
+#endif /* !__ASSEMBLY__ */
+
+#endif /* _ASM_I386_TREC_H */
diff --git a/include/asm-x86_64/trec.h b/include/asm-x86_64/trec.h
new file mode 100644
index 0000000..ba2a852
--- /dev/null
+++ b/include/asm-x86_64/trec.h
@@ -0,0 +1,13 @@
+/*
+ * Copyright (C) 2007 Saville Software, Inc.
+ *
+ * This code may be used for any purpose whatsoever, but
+ * no warranty of any kind is provided.
+ */
+
+#ifndef _ASM_X86_64_TREC_H
+#define _ASM_X86_64_TREC_H
+
+#include <asm-i386/trec.h>
+
+#endif /* _ASM_X86_64_TREC_H */
diff --git a/include/linux/trec.h b/include/linux/trec.h
new file mode 100644
index 0000000..d5d8e74
--- /dev/null
+++ b/include/linux/trec.h
@@ -0,0 +1,75 @@
+/*
+ * Copyright (C) 2007 Saville Software, Inc.
+ *
+ * This code may be used for any purpose whatsoever, but
+ * no warranty of any kind is provided.
+ */
+
+#ifndef _TREC_H
+#define _TREC_H
+
+#if defined(CONFIG_TREC)
+
+#include <linux/sched.h> /* For current->pid */
+#include <asm/processor.h> /* For current_text_addr */
+
+#define TREC_PC_ADDR ((unsigned long)(current_text_addr()))
+#define TREC_PID (current->pid)
+
+#ifndef TREC_ENABLED
+#define TREC_ENABLED 1
+#endif
+
+#define TREC(__v1, __v2) \
+ do { \
+ if (TREC_ENABLED) \
+ trec_write(TREC_PC_ADDR, TREC_PID, (unsigned long)(__v1), (unsigned long)(__v2)); \
+ } while (0)
+
+
+#define TRECC(__c, __v1, __v2) do { if ((__c)) TREC(__v1, __v2); } while (0)
+#define TRECC0(__c) TRECC(__c, 0, 0)
+#define TRECC1(__c, __v1) TRECC(__c, __v1, 0)
+#define TRECC2(__c, __v1, __v2) TRECC(__c, __v1, __v2)
+#define TRECC0_RETV(__c,__retv) do { TRECC0(__c); return(__retv); } while (0)
+#define TRECC0_RET(__c) do { TRECC0(__c); return; } while (0)
+
+#define TREC0() TRECC0(1)
+#define TREC1(__v) TRECC1(1, (__v))
+#define TREC2(__v1, __v2) TRECC2(1, (__v1), (__v2))
+#define TREC_RETV(__retv) TRECC0_RETV(1, __retv)
+#define TREC_RET() TRECC0_RET(1)
+
+extern void trec_init(void);
+extern void trec_write(unsigned long pc, int pid, unsigned long v1, unsigned long v2);
+extern void trec_snapshot(void);
+extern void trec_print_snapshot(void);
+
+#else
+
+/*
+ * All TREC's are disabled
+ */
+#define TREC_ENABLED 0
+
+#define TREC(__v1, __v2) do { } while (0)
+
+#define TRECC(__c,__v1, __v2) do { } while (0)
+#define TRECC0(__c) do { } while (0)
+#define TRECC1(__c, __v) do { } while (0)
+#define TRECC2(__c, __v1, __v2) do { } while (0)
+
+#define TREC0() do { } while (0)
+#define TREC1(__v) do { } while (0)
+#define TREC2(__v1, __v2) do { } while (0)
+#define TREC_RETV(__retv) do { return(__retv); } while (0)
+#define TREC_RET() do { return; } while (0)
+
+static inline void trec_init(void) {}
+static inline void trec_write(unsigned long pc, int pid, unsigned long v1, unsigned long v2) {}
+static inline void trec_snapshot(void) {}
+static inline void trec_print_snapshot(void) {}
+
+#endif /* CONFIG_TREC && !TREC_DISABLED */
+
+#endif /* _TREC_H */
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 3f3e740..db53fdb 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -303,6 +303,13 @@ config STACKTRACE
depends on DEBUG_KERNEL
depends on STACKTRACE_SUPPORT

+config TREC
+ def_bool n
+ bool "Trace record support"
+ depends on DEBUG_KERNEL
+ help
+ Trace records are a light weight tracing facility
+
config DEBUG_KOBJECT
bool "kobject debugging"
depends on DEBUG_KERNEL
--
1.5.0.rc2

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Next message: Ken Chen: "Re: [PATCH] max_loop limit"
Previous message: Wink Saville: "[PATCH 3/3] Initialize and use trec_snapshot and trec_print_snapshot."
In reply to: Wink Saville: "[PATCH 1/3] Documention for trace records (trec)."
Next in thread: Wink Saville: "[PATCH 3/3] Initialize and use trec_snapshot and trec_print_snapshot."
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]