summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorMike Frysinger <vapier@gentoo.org>2010-01-26 10:40:03 +0100
committerFrederic Weisbecker <fweisbec@gmail.com>2010-02-17 13:07:21 +0100
commite7b8e675d9c71b868b66f62f725a948047514719 (patch)
tree77877e2470148dc47653408c4b624734a8f14239
parenttracing: Simplify test for function_graph tracing start point (diff)
downloadlinux-e7b8e675d9c71b868b66f62f725a948047514719.tar.xz
linux-e7b8e675d9c71b868b66f62f725a948047514719.zip
tracing: Unify arch_syscall_addr() implementations
Most implementations of arch_syscall_addr() are the same, so create a default version in common code and move the one piece that differs (the syscall table) to asm/syscall.h. New arch ports don't have to waste time copying & pasting this simple function. The s390/sparc versions need to be different, so document why. Signed-off-by: Mike Frysinger <vapier@gentoo.org> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Paul Mundt <lethal@linux-sh.org> Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1264498803-17278-1-git-send-email-vapier@gentoo.org> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
-rw-r--r--Documentation/trace/ftrace-design.txt5
-rw-r--r--arch/s390/include/asm/syscall.h7
-rw-r--r--arch/s390/kernel/ftrace.c10
-rw-r--r--arch/sh/include/asm/syscall.h2
-rw-r--r--arch/sh/kernel/ftrace.c9
-rw-r--r--arch/sparc/include/asm/syscall.h7
-rw-r--r--arch/sparc/kernel/ftrace.c11
-rw-r--r--arch/x86/include/asm/syscall.h2
-rw-r--r--arch/x86/kernel/ftrace.c10
-rw-r--r--include/linux/ftrace.h6
-rw-r--r--kernel/trace/trace_syscalls.c5
11 files changed, 31 insertions, 43 deletions
diff --git a/Documentation/trace/ftrace-design.txt b/Documentation/trace/ftrace-design.txt
index 239f14b2b55a..99df1101d2a5 100644
--- a/Documentation/trace/ftrace-design.txt
+++ b/Documentation/trace/ftrace-design.txt
@@ -218,11 +218,10 @@ HAVE_SYSCALL_TRACEPOINTS
You need very few things to get the syscalls tracing in an arch.
+- Support HAVE_ARCH_TRACEHOOK (see arch/Kconfig).
- Have a NR_syscalls variable in <asm/unistd.h> that provides the number
of syscalls supported by the arch.
-- Implement arch_syscall_addr() that resolves a syscall address from a
- syscall number.
-- Support the TIF_SYSCALL_TRACEPOINT thread flags
+- Support the TIF_SYSCALL_TRACEPOINT thread flags.
- Put the trace_sys_enter() and trace_sys_exit() tracepoints calls from ptrace
in the ptrace syscalls tracing path.
- Tag this arch as HAVE_SYSCALL_TRACEPOINTS.
diff --git a/arch/s390/include/asm/syscall.h b/arch/s390/include/asm/syscall.h
index e0a73d3eb837..8429686951f9 100644
--- a/arch/s390/include/asm/syscall.h
+++ b/arch/s390/include/asm/syscall.h
@@ -15,6 +15,13 @@
#include <linux/sched.h>
#include <asm/ptrace.h>
+/*
+ * The syscall table always contains 32 bit pointers since we know that the
+ * address of the function to be called is (way) below 4GB. So the "int"
+ * type here is what we want [need] for both 32 bit and 64 bit systems.
+ */
+extern const unsigned int sys_call_table[];
+
static inline long syscall_get_nr(struct task_struct *task,
struct pt_regs *regs)
{
diff --git a/arch/s390/kernel/ftrace.c b/arch/s390/kernel/ftrace.c
index 5a82bc68193e..9e69449e77ad 100644
--- a/arch/s390/kernel/ftrace.c
+++ b/arch/s390/kernel/ftrace.c
@@ -200,13 +200,3 @@ out:
return parent;
}
#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
-
-#ifdef CONFIG_FTRACE_SYSCALLS
-
-extern unsigned int sys_call_table[];
-
-unsigned long __init arch_syscall_addr(int nr)
-{
- return (unsigned long)sys_call_table[nr];
-}
-#endif
diff --git a/arch/sh/include/asm/syscall.h b/arch/sh/include/asm/syscall.h
index 6a381429ee9d..aa7777bdc370 100644
--- a/arch/sh/include/asm/syscall.h
+++ b/arch/sh/include/asm/syscall.h
@@ -1,6 +1,8 @@
#ifndef __ASM_SH_SYSCALL_H
#define __ASM_SH_SYSCALL_H
+extern const unsigned long sys_call_table[];
+
#ifdef CONFIG_SUPERH32
# include "syscall_32.h"
#else
diff --git a/arch/sh/kernel/ftrace.c b/arch/sh/kernel/ftrace.c
index a48cdedc73b5..30e13196d35b 100644
--- a/arch/sh/kernel/ftrace.c
+++ b/arch/sh/kernel/ftrace.c
@@ -399,12 +399,3 @@ void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr)
}
}
#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
-
-#ifdef CONFIG_FTRACE_SYSCALLS
-extern unsigned long *sys_call_table;
-
-unsigned long __init arch_syscall_addr(int nr)
-{
- return (unsigned long)sys_call_table[nr];
-}
-#endif /* CONFIG_FTRACE_SYSCALLS */
diff --git a/arch/sparc/include/asm/syscall.h b/arch/sparc/include/asm/syscall.h
index 7486c605e23c..025a02ad2e31 100644
--- a/arch/sparc/include/asm/syscall.h
+++ b/arch/sparc/include/asm/syscall.h
@@ -5,6 +5,13 @@
#include <linux/sched.h>
#include <asm/ptrace.h>
+/*
+ * The syscall table always contains 32 bit pointers since we know that the
+ * address of the function to be called is (way) below 4GB. So the "int"
+ * type here is what we want [need] for both 32 bit and 64 bit systems.
+ */
+extern const unsigned int sys_call_table[];
+
/* The system call number is given by the user in %g1 */
static inline long syscall_get_nr(struct task_struct *task,
struct pt_regs *regs)
diff --git a/arch/sparc/kernel/ftrace.c b/arch/sparc/kernel/ftrace.c
index 29973daa9930..9103a56b39e8 100644
--- a/arch/sparc/kernel/ftrace.c
+++ b/arch/sparc/kernel/ftrace.c
@@ -91,14 +91,3 @@ int __init ftrace_dyn_arch_init(void *data)
return 0;
}
#endif
-
-#ifdef CONFIG_FTRACE_SYSCALLS
-
-extern unsigned int sys_call_table[];
-
-unsigned long __init arch_syscall_addr(int nr)
-{
- return (unsigned long)sys_call_table[nr];
-}
-
-#endif
diff --git a/arch/x86/include/asm/syscall.h b/arch/x86/include/asm/syscall.h
index 8d33bc5462d1..c4a348f7bd43 100644
--- a/arch/x86/include/asm/syscall.h
+++ b/arch/x86/include/asm/syscall.h
@@ -16,6 +16,8 @@
#include <linux/sched.h>
#include <linux/err.h>
+extern const unsigned long sys_call_table[];
+
/*
* Only the low 32 bits of orig_ax are meaningful, so we return int.
* This importantly ignores the high bits on 64-bit, so comparisons
diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c
index 309689245431..0d93a941934c 100644
--- a/arch/x86/kernel/ftrace.c
+++ b/arch/x86/kernel/ftrace.c
@@ -484,13 +484,3 @@ void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr,
}
}
#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
-
-#ifdef CONFIG_FTRACE_SYSCALLS
-
-extern unsigned long *sys_call_table;
-
-unsigned long __init arch_syscall_addr(int nr)
-{
- return (unsigned long)(&sys_call_table)[nr];
-}
-#endif
diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h
index 0b4f97d24d7f..1cbb36f2759c 100644
--- a/include/linux/ftrace.h
+++ b/include/linux/ftrace.h
@@ -511,4 +511,10 @@ static inline void trace_hw_branch_oops(void) {}
#endif /* CONFIG_HW_BRANCH_TRACER */
+#ifdef CONFIG_FTRACE_SYSCALLS
+
+unsigned long arch_syscall_addr(int nr);
+
+#endif /* CONFIG_FTRACE_SYSCALLS */
+
#endif /* _LINUX_FTRACE_H */
diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c
index 49cea70fbf6d..ecf00782b46c 100644
--- a/kernel/trace/trace_syscalls.c
+++ b/kernel/trace/trace_syscalls.c
@@ -394,6 +394,11 @@ int init_syscall_trace(struct ftrace_event_call *call)
return id;
}
+unsigned long __init arch_syscall_addr(int nr)
+{
+ return (unsigned long)sys_call_table[nr];
+}
+
int __init init_ftrace_syscalls(void)
{
struct syscall_metadata *meta;