[PATCH] Bring sparc64 dynamic ftrace up to snuff...

From: David Miller
Date: Sat Jun 13 2009 - 04:10:39 EST



Do the ftrace maintainers mind if I merge the following in via my
sparc-next-2.6 tree?

Thanks!

sparc64: Add proper dynamic ftrace support.

Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
---
arch/sparc/Kconfig | 2 +
arch/sparc/include/asm/ftrace.h | 11 +++++++++
arch/sparc/kernel/ftrace.c | 47 ++++++++++++++++++++++++++------------
scripts/recordmcount.pl | 20 ++++++++++++++++
4 files changed, 65 insertions(+), 15 deletions(-)

diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
index 2185cf9..3f8b6a9 100644
--- a/arch/sparc/Kconfig
+++ b/arch/sparc/Kconfig
@@ -37,6 +37,8 @@ config SPARC64
select HAVE_KPROBES
select HAVE_LMB
select HAVE_SYSCALL_WRAPPERS
+ select HAVE_DYNAMIC_FTRACE
+ select HAVE_FTRACE_MCOUNT_RECORD
select USE_GENERIC_SMP_HELPERS if SMP
select RTC_DRV_CMOS
select RTC_DRV_BQ4802
diff --git a/arch/sparc/include/asm/ftrace.h b/arch/sparc/include/asm/ftrace.h
index d27716c..b0f18e9 100644
--- a/arch/sparc/include/asm/ftrace.h
+++ b/arch/sparc/include/asm/ftrace.h
@@ -11,4 +11,15 @@ extern void _mcount(void);

#endif

+#ifdef CONFIG_DYNAMIC_FTRACE
+/* reloction of mcount call site is the same as the address */
+static inline unsigned long ftrace_call_adjust(unsigned long addr)
+{
+ return addr;
+}
+
+struct dyn_arch_ftrace {
+};
+#endif /* CONFIG_DYNAMIC_FTRACE */
+
#endif /* _ASM_SPARC64_FTRACE */
diff --git a/arch/sparc/kernel/ftrace.c b/arch/sparc/kernel/ftrace.c
index d0218e7..d3b1a30 100644
--- a/arch/sparc/kernel/ftrace.c
+++ b/arch/sparc/kernel/ftrace.c
@@ -7,14 +7,10 @@

#include <asm/ftrace.h>

+#ifdef CONFIG_DYNAMIC_FTRACE
static const u32 ftrace_nop = 0x01000000;

-unsigned char *ftrace_nop_replace(void)
-{
- return (char *)&ftrace_nop;
-}
-
-unsigned char *ftrace_call_replace(unsigned long ip, unsigned long addr)
+static u32 ftrace_call_replace(unsigned long ip, unsigned long addr)
{
static u32 call;
s32 off;
@@ -22,15 +18,11 @@ unsigned char *ftrace_call_replace(unsigned long ip, unsigned long addr)
off = ((s32)addr - (s32)ip);
call = 0x40000000 | ((u32)off >> 2);

- return (unsigned char *) &call;
+ return call;
}

-int
-ftrace_modify_code(unsigned long ip, unsigned char *old_code,
- unsigned char *new_code)
+static int ftrace_modify_code(unsigned long ip, u32 old, u32 new)
{
- u32 old = *(u32 *)old_code;
- u32 new = *(u32 *)new_code;
u32 replaced;
int faulted;

@@ -59,18 +51,43 @@ ftrace_modify_code(unsigned long ip, unsigned char *old_code,
return faulted;
}

+int ftrace_make_nop(struct module *mod, struct dyn_ftrace *rec, unsigned long addr)
+{
+ unsigned long ip = rec->ip;
+ u32 old, new;
+
+ old = ftrace_call_replace(ip, addr);
+ new = ftrace_nop;
+ return ftrace_modify_code(ip, old, new);
+}
+
+int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
+{
+ unsigned long ip = rec->ip;
+ u32 old, new;
+
+ old = ftrace_nop;
+ new = ftrace_call_replace(ip, addr);
+ return ftrace_modify_code(ip, old, new);
+}
+
int ftrace_update_ftrace_func(ftrace_func_t func)
{
unsigned long ip = (unsigned long)(&ftrace_call);
- unsigned char old[MCOUNT_INSN_SIZE], *new;
+ u32 old, new;

- memcpy(old, &ftrace_call, MCOUNT_INSN_SIZE);
+ old = *(u32 *) &ftrace_call;
new = ftrace_call_replace(ip, (unsigned long)func);
return ftrace_modify_code(ip, old, new);
}

int __init ftrace_dyn_arch_init(void *data)
{
- ftrace_mcount_set(data);
+ unsigned long *p = data;
+
+ *p = 0;
+
return 0;
}
+#endif
+
diff --git a/scripts/recordmcount.pl b/scripts/recordmcount.pl
index 409596e..e694eaf 100755
--- a/scripts/recordmcount.pl
+++ b/scripts/recordmcount.pl
@@ -213,6 +213,26 @@ if ($arch eq "x86_64") {
if ($is_module eq "0") {
$cc .= " -mconstant-gp";
}
+} elsif ($arch eq "sparc64") {
+ # In the objdump output there are giblets like:
+ # 0000000000000000 <igmp_net_exit-0x18>:
+ # As there's some data blobs that get emitted into the
+ # text section before the first instructions and the first
+ # real symbols. We don't want to match that, so to combat
+ # this we use '\w' so we'll match just plain symbol names,
+ # and not those that also include hex offsets inside of the
+ # '<>' brackets. Actually the generic function_regex setting
+ # could safely use this too.
+ $function_regex = "^([0-9a-fA-F]+)\\s+<(\\w*?)>:";
+
+ # Sparc64 calls '_mcount' instead of plain 'mcount'.
+ $mcount_regex = "^\\s*([0-9a-fA-F]+):.*\\s_mcount\$";
+
+ $alignment = 8;
+ $type = ".xword";
+ $ld .= " -m elf64_sparc";
+ $cc .= " -m64";
+ $objcopy .= " -O elf64-sparc";
} else {
die "Arch $arch is not supported with CONFIG_FTRACE_MCOUNT_RECORD";
}
--
1.6.3.2

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