From: Jeff Dike <jdike@addtoit.com>
This patch makes some debug code in the system call path configurable.
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---
25-akpm/arch/um/Kconfig.debug | 10 ++++++
25-akpm/arch/um/defconfig | 10 ++++--
25-akpm/arch/um/kernel/Makefile | 1
25-akpm/arch/um/kernel/skas/syscall_user.c | 9 +++++
25-akpm/arch/um/kernel/syscall_kern.c | 16 +++++++++
25-akpm/arch/um/kernel/syscall_user.c | 48 +++++++++++++++++++++++++++++
25-akpm/arch/um/kernel/tt/syscall_kern.c | 2 +
25-akpm/arch/um/kernel/tt/syscall_user.c | 9 +++++
25-akpm/arch/um/kernel/tt/tracer.c | 23 ++++++++++++-
9 files changed, 124 insertions(+), 4 deletions(-)
diff -puN arch/um/defconfig~uml-make-syscall-debugging-code-configurable arch/um/defconfig
--- 25/arch/um/defconfig~uml-make-syscall-debugging-code-configurable 2005-03-07 22:16:18.000000000 -0800
+++ 25-akpm/arch/um/defconfig 2005-03-07 22:16:18.000000000 -0800
@@ -52,7 +52,6 @@ CONFIG_BSD_PROCESS_ACCT=y
# CONFIG_BSD_PROCESS_ACCT_V3 is not set
CONFIG_SYSCTL=y
# CONFIG_AUDIT is not set
-CONFIG_LOG_BUF_SHIFT=14
# CONFIG_HOTPLUG is not set
CONFIG_KOBJECT_UEVENT=y
CONFIG_IKCONFIG=y
@@ -61,9 +60,10 @@ CONFIG_IKCONFIG_PROC=y
CONFIG_KALLSYMS=y
# CONFIG_KALLSYMS_ALL is not set
CONFIG_KALLSYMS_EXTRA_PASS=y
+CONFIG_BASE_FULL=y
+CONFIG_BASE_SMALL=0
CONFIG_FUTEX=y
CONFIG_EPOLL=y
-# CONFIG_CC_OPTIMIZE_FOR_SIZE is not set
CONFIG_SHMEM=y
CONFIG_CC_ALIGN_FUNCTIONS=0
CONFIG_CC_ALIGN_LABELS=0
@@ -241,6 +241,11 @@ CONFIG_TUN=m
# CONFIG_NET_PCMCIA is not set
#
+# PCMCIA network device support
+#
+# CONFIG_NET_PCMCIA is not set
+
+#
# Wan interfaces
#
# CONFIG_WAN is not set
@@ -437,3 +442,4 @@ CONFIG_FRAME_POINTER=y
CONFIG_PT_PROXY=y
# CONFIG_GPROF is not set
# CONFIG_GCOV is not set
+# CONFIG_SYSCALL_DEBUG is not set
diff -puN arch/um/Kconfig.debug~uml-make-syscall-debugging-code-configurable arch/um/Kconfig.debug
--- 25/arch/um/Kconfig.debug~uml-make-syscall-debugging-code-configurable 2005-03-07 22:16:18.000000000 -0800
+++ 25-akpm/arch/um/Kconfig.debug 2005-03-07 22:16:18.000000000 -0800
@@ -40,4 +40,14 @@ config GCOV
If you're involved in UML kernel development and want to use gcov,
say Y. If you're unsure, say N.
+config SYSCALL_DEBUG
+ bool "Enable system call debugging"
+ default N
+ depends on DEBUG_INFO
+ help
+ This adds some system debugging to UML, including keeping a ring buffer
+ with recent system calls and some global and per-task statistics.
+
+ If unsure, say N
+
endmenu
diff -puN arch/um/kernel/Makefile~uml-make-syscall-debugging-code-configurable arch/um/kernel/Makefile
--- 25/arch/um/kernel/Makefile~uml-make-syscall-debugging-code-configurable 2005-03-07 22:16:18.000000000 -0800
+++ 25-akpm/arch/um/kernel/Makefile 2005-03-07 22:16:18.000000000 -0800
@@ -18,6 +18,7 @@ obj-$(CONFIG_BLK_DEV_INITRD) += initrd_k
obj-$(CONFIG_GPROF) += gprof_syms.o
obj-$(CONFIG_GCOV) += gmon_syms.o
obj-$(CONFIG_TTY_LOG) += tty_log.o
+obj-$(CONFIG_SYSCALL_DEBUG) += syscall_user.o
obj-$(CONFIG_MODE_TT) += tt/
obj-$(CONFIG_MODE_SKAS) += skas/
diff -puN arch/um/kernel/skas/syscall_user.c~uml-make-syscall-debugging-code-configurable arch/um/kernel/skas/syscall_user.c
--- 25/arch/um/kernel/skas/syscall_user.c~uml-make-syscall-debugging-code-configurable 2005-03-07 22:16:18.000000000 -0800
+++ 25-akpm/arch/um/kernel/skas/syscall_user.c 2005-03-07 22:16:18.000000000 -0800
@@ -6,6 +6,7 @@
#include <stdlib.h>
#include <signal.h>
#include "kern_util.h"
+#include "uml-config.h"
#include "syscall_user.h"
#include "sysdep/ptrace.h"
#include "sysdep/sigcontext.h"
@@ -14,6 +15,11 @@
void handle_syscall(union uml_pt_regs *regs)
{
long result;
+#if UML_CONFIG_SYSCALL_DEBUG
+ int index;
+
+ index = record_syscall_start(UPT_SYSCALL_NR(regs));
+#endif
syscall_trace(regs, 0);
result = execute_syscall_skas(regs);
@@ -21,6 +27,9 @@ void handle_syscall(union uml_pt_regs *r
REGS_SET_SYSCALL_RETURN(regs->skas.regs, result);
syscall_trace(regs, 1);
+#if UML_CONFIG_SYSCALL_DEBUG
+ record_syscall_end(index, result);
+#endif
}
/*
diff -puN arch/um/kernel/syscall_kern.c~uml-make-syscall-debugging-code-configurable arch/um/kernel/syscall_kern.c
--- 25/arch/um/kernel/syscall_kern.c~uml-make-syscall-debugging-code-configurable 2005-03-07 22:16:18.000000000 -0800
+++ 25-akpm/arch/um/kernel/syscall_kern.c 2005-03-07 22:16:18.000000000 -0800
@@ -154,6 +154,22 @@ long sys_olduname(struct oldold_utsname
return error;
}
+DEFINE_SPINLOCK(syscall_lock);
+
+static int syscall_index = 0;
+
+int next_syscall_index(int limit)
+{
+ int ret;
+
+ spin_lock(&syscall_lock);
+ ret = syscall_index;
+ if(++syscall_index == limit)
+ syscall_index = 0;
+ spin_unlock(&syscall_lock);
+ return(ret);
+}
+
/*
* Overrides for Emacs so that we follow Linus's tabbing style.
* Emacs will notice this stuff at the end of the file and automatically
diff -puN arch/um/kernel/syscall_user.c~uml-make-syscall-debugging-code-configurable arch/um/kernel/syscall_user.c
--- 25/arch/um/kernel/syscall_user.c~uml-make-syscall-debugging-code-configurable 2005-03-07 22:16:18.000000000 -0800
+++ 25-akpm/arch/um/kernel/syscall_user.c 2005-03-07 22:16:18.000000000 -0800
@@ -46,3 +46,51 @@ void record_syscall_end(int index, long
* c-file-style: "linux"
* End:
*/
+/*
+ * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#include <stdlib.h>
+#include <sys/time.h>
+#include "kern_util.h"
+#include "syscall_user.h"
+
+struct {
+ int syscall;
+ int pid;
+ long result;
+ struct timeval start;
+ struct timeval end;
+} syscall_record[1024];
+
+int record_syscall_start(int syscall)
+{
+ int max, index;
+
+ max = sizeof(syscall_record)/sizeof(syscall_record[0]);
+ index = next_syscall_index(max);
+
+ syscall_record[index].syscall = syscall;
+ syscall_record[index].pid = current_pid();
+ syscall_record[index].result = 0xdeadbeef;
+ gettimeofday(&syscall_record[index].start, NULL);
+ return(index);
+}
+
+void record_syscall_end(int index, long result)
+{
+ syscall_record[index].result = result;
+ gettimeofday(&syscall_record[index].end, NULL);
+}
+
+/*
+ * Overrides for Emacs so that we follow Linus's tabbing style.
+ * Emacs will notice this stuff at the end of the file and automatically
+ * adjust the settings for this buffer only. This must remain at the end
+ * of the file.
+ * ---------------------------------------------------------------------------
+ * Local variables:
+ * c-file-style: "linux"
+ * End:
+ */
diff -puN arch/um/kernel/tt/syscall_kern.c~uml-make-syscall-debugging-code-configurable arch/um/kernel/tt/syscall_kern.c
--- 25/arch/um/kernel/tt/syscall_kern.c~uml-make-syscall-debugging-code-configurable 2005-03-07 22:16:18.000000000 -0800
+++ 25-akpm/arch/um/kernel/tt/syscall_kern.c 2005-03-07 22:16:18.000000000 -0800
@@ -22,8 +22,10 @@ long execute_syscall_tt(void *r)
long res;
int syscall;
+#ifdef CONFIG_SYSCALL_DEBUG
current->thread.nsyscalls++;
nsyscalls++;
+#endif
syscall = UPT_SYSCALL_NR(®s->regs);
if((syscall >= NR_syscalls) || (syscall < 0))
diff -puN arch/um/kernel/tt/syscall_user.c~uml-make-syscall-debugging-code-configurable arch/um/kernel/tt/syscall_user.c
--- 25/arch/um/kernel/tt/syscall_user.c~uml-make-syscall-debugging-code-configurable 2005-03-07 22:16:18.000000000 -0800
+++ 25-akpm/arch/um/kernel/tt/syscall_user.c 2005-03-07 22:16:18.000000000 -0800
@@ -23,11 +23,17 @@ void syscall_handler_tt(int sig, union u
void *sc;
long result;
int syscall;
+#ifdef UML_CONFIG_DEBUG_SYSCALL
+ int index;
+#endif
syscall = UPT_SYSCALL_NR(regs);
sc = UPT_SC(regs);
SC_START_SYSCALL(sc);
+#ifdef UML_CONFIG_DEBUG_SYSCALL
+ index = record_syscall_start(syscall);
+#endif
syscall_trace(regs, 0);
result = execute_syscall_tt(regs);
@@ -39,6 +45,9 @@ void syscall_handler_tt(int sig, union u
SC_SET_SYSCALL_RETURN(sc, result);
syscall_trace(regs, 1);
+#ifdef UML_CONFIG_DEBUG_SYSCALL
+ record_syscall_end(index, result);
+#endif
}
void do_sigtrap(void *task)
diff -puN arch/um/kernel/tt/tracer.c~uml-make-syscall-debugging-code-configurable arch/um/kernel/tt/tracer.c
--- 25/arch/um/kernel/tt/tracer.c~uml-make-syscall-debugging-code-configurable 2005-03-07 22:16:18.000000000 -0800
+++ 25-akpm/arch/um/kernel/tt/tracer.c 2005-03-07 22:16:18.000000000 -0800
@@ -13,7 +13,6 @@
#include <string.h>
#include <sys/mman.h>
#include <sys/ptrace.h>
-#include <linux/ptrace.h>
#include <sys/time.h>
#include <sys/wait.h>
#include "user.h"
@@ -187,7 +186,10 @@ int tracer(int (*init_proc)(void *), voi
int status, pid = 0, sig = 0, cont_type, tracing = 0, op = 0;
int proc_id = 0, n, err, old_tracing = 0, strace = 0;
int local_using_sysemu = 0;
-
+#ifdef UML_CONFIG_SYSCALL_DEBUG
+ unsigned long eip = 0;
+ int last_index;
+#endif
signal(SIGPIPE, SIG_IGN);
setup_tracer_winch();
tracing_pid = os_getpid();
@@ -278,6 +280,23 @@ int tracer(int (*init_proc)(void *), voi
else if(WIFSTOPPED(status)){
proc_id = pid_to_processor_id(pid);
sig = WSTOPSIG(status);
+#ifdef UML_CONFIG_SYSCALL_DEBUG
+ if(signal_index[proc_id] == 1024){
+ signal_index[proc_id] = 0;
+ last_index = 1023;
+ }
+ else last_index = signal_index[proc_id] - 1;
+ if(((sig == SIGPROF) || (sig == SIGVTALRM) ||
+ (sig == SIGALRM)) &&
+ (signal_record[proc_id][last_index].signal == sig)&&
+ (signal_record[proc_id][last_index].pid == pid))
+ signal_index[proc_id] = last_index;
+ signal_record[proc_id][signal_index[proc_id]].pid = pid;
+ gettimeofday(&signal_record[proc_id][signal_index[proc_id]].time, NULL);
+ eip = ptrace(PTRACE_PEEKUSER, pid, PT_IP_OFFSET, 0);
+ signal_record[proc_id][signal_index[proc_id]].addr = eip;
+ signal_record[proc_id][signal_index[proc_id]++].signal = sig;
+#endif
if(proc_id == -1){
sleeping_process_signal(pid, sig);
continue;
_