Re: [PATCH] Fix Immediate Values x86_64 support old gcc (v3)

From: Mathieu Desnoyers
Date: Wed May 21 2008 - 19:24:46 EST


GCC < 4, on x86_64, does not accept symbol+offset operands for "i" constraints
asm statements. Fallback on generic immediate values if this compiler is
detected.

Changelog :
- USE_IMMEDIATE must now be used in lieue of CONFIG_IMMEDIATE in Makefiles and
in C code.
- Every architecture implementing immediate values must declare USE_IMMEDIATE
in their Makefile.
- Tab -> spaces in Makefiles.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxx>
CC: Sam Ravnborg <sam@xxxxxxxxxxxx>
CC: "H. Peter Anvin" <hpa@xxxxxxxxx>
CC: Jeremy Fitzhardinge <jeremy@xxxxxxxx>
CC: Ingo Molnar <mingo@xxxxxxx>
CC: David Miller <davem@xxxxxxxxxxxxx>
CC: Paul Mackerras <paulus@xxxxxxxxx>
---
Makefile | 5 +++++
arch/powerpc/Makefile | 2 ++
arch/powerpc/kernel/Makefile | 2 +-
arch/x86/Makefile | 5 +++++
arch/x86/kernel/Makefile | 2 +-
arch/x86/kernel/traps_32.c | 4 ++--
include/linux/immediate.h | 2 +-
include/linux/module.h | 4 ++--
kernel/Makefile | 2 +-
kernel/module.c | 8 ++++----
10 files changed, 24 insertions(+), 12 deletions(-)

Index: linux-2.6-sched-devel/arch/x86/Makefile
===================================================================
--- linux-2.6-sched-devel.orig/arch/x86/Makefile 2008-05-21 15:16:06.000000000 -0400
+++ linux-2.6-sched-devel/arch/x86/Makefile 2008-05-21 15:53:00.000000000 -0400
@@ -43,6 +43,7 @@

# temporary until string.h is fixed
KBUILD_CFLAGS += -ffreestanding
+ export USE_IMMEDIATE := $(CONFIG_IMMEDIATE)
else
BITS := 64
UTS_MACHINE := x86_64
@@ -78,6 +79,10 @@
"$(CC)" -fstack-protector-all )

KBUILD_CFLAGS += $(stackp-y)
+
+ # x86_64 gcc 3.x has problems with passing symbol+offset in
+ # asm "i" constraint.
+ export USE_IMMEDIATE := $(call cc-ifversion, -ge, 0400, $(CONFIG_IMMEDIATE))
endif

# Stackpointer is addressed different for 32 bit and 64 bit x86
Index: linux-2.6-sched-devel/include/linux/immediate.h
===================================================================
--- linux-2.6-sched-devel.orig/include/linux/immediate.h 2008-05-21 15:16:06.000000000 -0400
+++ linux-2.6-sched-devel/include/linux/immediate.h 2008-05-21 15:16:59.000000000 -0400
@@ -10,7 +10,7 @@
* See the file COPYING for more details.
*/

-#ifdef CONFIG_IMMEDIATE
+#ifdef USE_IMMEDIATE

#include <asm/immediate.h>

Index: linux-2.6-sched-devel/arch/x86/kernel/Makefile
===================================================================
--- linux-2.6-sched-devel.orig/arch/x86/kernel/Makefile 2008-05-21 15:16:51.000000000 -0400
+++ linux-2.6-sched-devel/arch/x86/kernel/Makefile 2008-05-21 15:16:59.000000000 -0400
@@ -75,7 +75,7 @@
obj-$(CONFIG_KPROBES) += kprobes.o
obj-$(CONFIG_MODULES) += module_$(BITS).o
obj-$(CONFIG_ACPI_SRAT) += srat_32.o
-obj-$(CONFIG_IMMEDIATE) += immediate.o
+obj-$(USE_IMMEDIATE) += immediate.o
obj-$(CONFIG_EFI) += efi.o efi_$(BITS).o efi_stub_$(BITS).o
obj-$(CONFIG_DOUBLEFAULT) += doublefault_32.o
obj-$(CONFIG_KGDB) += kgdb.o
Index: linux-2.6-sched-devel/kernel/Makefile
===================================================================
--- linux-2.6-sched-devel.orig/kernel/Makefile 2008-05-21 15:16:52.000000000 -0400
+++ linux-2.6-sched-devel/kernel/Makefile 2008-05-21 15:16:59.000000000 -0400
@@ -75,7 +75,7 @@
obj-$(CONFIG_SYSCTL) += utsname_sysctl.o
obj-$(CONFIG_TASK_DELAY_ACCT) += delayacct.o
obj-$(CONFIG_TASKSTATS) += taskstats.o tsacct.o
-obj-$(CONFIG_IMMEDIATE) += immediate.o
+obj-$(USE_IMMEDIATE) += immediate.o
obj-$(CONFIG_MARKERS) += marker.o
obj-$(CONFIG_LATENCYTOP) += latencytop.o
obj-$(CONFIG_FTRACE) += trace/
Index: linux-2.6-sched-devel/arch/powerpc/Makefile
===================================================================
--- linux-2.6-sched-devel.orig/arch/powerpc/Makefile 2008-05-21 15:16:06.000000000 -0400
+++ linux-2.6-sched-devel/arch/powerpc/Makefile 2008-05-21 15:16:59.000000000 -0400
@@ -98,6 +98,8 @@
endif
endif

+export USE_IMMEDIATE := $(CONFIG_IMMEDIATE)
+
ifeq ($(CONFIG_TUNE_CELL),y)
KBUILD_CFLAGS += $(call cc-option,-mtune=cell)
endif
Index: linux-2.6-sched-devel/Makefile
===================================================================
--- linux-2.6-sched-devel.orig/Makefile 2008-05-21 15:16:51.000000000 -0400
+++ linux-2.6-sched-devel/Makefile 2008-05-21 15:16:59.000000000 -0400
@@ -532,6 +532,11 @@
KBUILD_CFLAGS += -pg
endif

+# arch Makefile detects if the compiler permits use of immediate values
+ifdef USE_IMMEDIATE
+KBUILD_CFLAGS += -DUSE_IMMEDIATE
+endif
+
# We trigger additional mismatches with less inlining
ifdef CONFIG_DEBUG_SECTION_MISMATCH
KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
Index: linux-2.6-sched-devel/arch/powerpc/kernel/Makefile
===================================================================
--- linux-2.6-sched-devel.orig/arch/powerpc/kernel/Makefile 2008-05-21 15:16:06.000000000 -0400
+++ linux-2.6-sched-devel/arch/powerpc/kernel/Makefile 2008-05-21 15:16:59.000000000 -0400
@@ -45,7 +45,7 @@
obj64-$(CONFIG_HIBERNATION) += swsusp_asm64.o
obj-$(CONFIG_MODULES) += module_$(CONFIG_WORD_SIZE).o
obj-$(CONFIG_44x) += cpu_setup_44x.o
-obj-$(CONFIG_IMMEDIATE) += immediate.o
+obj-$(USE_IMMEDIATE) += immediate.o

ifeq ($(CONFIG_PPC_MERGE),y)

Index: linux-2.6-sched-devel/kernel/module.c
===================================================================
--- linux-2.6-sched-devel.orig/kernel/module.c 2008-05-21 15:16:52.000000000 -0400
+++ linux-2.6-sched-devel/kernel/module.c 2008-05-21 15:16:59.000000000 -0400
@@ -2013,7 +2013,7 @@
mod->gpl_future_syms = (void *)sechdrs[gplfutureindex].sh_addr;
if (gplfuturecrcindex)
mod->gpl_future_crcs = (void *)sechdrs[gplfuturecrcindex].sh_addr;
-#ifdef CONFIG_IMMEDIATE
+#ifdef USE_IMMEDIATE
mod->immediate = (void *)sechdrs[immediateindex].sh_addr;
mod->num_immediate =
sechdrs[immediateindex].sh_size / sizeof(*mod->immediate);
@@ -2097,7 +2097,7 @@
marker_update_probe_range(mod->markers,
mod->markers + mod->num_markers);
#endif
-#ifdef CONFIG_IMMEDIATE
+#ifdef USE_IMMEDIATE
/* Immediate values must be updated after markers */
imv_update_range(mod->immediate,
mod->immediate + mod->num_immediate);
@@ -2258,7 +2258,7 @@
/* Drop initial reference. */
module_put(mod);
unwind_remove_table(mod->unwind_info, 1);
-#ifdef CONFIG_IMMEDIATE
+#ifdef USE_IMMEDIATE
imv_unref(mod->immediate, mod->immediate + mod->num_immediate,
mod->module_init, mod->init_size);
#endif
@@ -2657,7 +2657,7 @@
}
#endif

-#ifdef CONFIG_IMMEDIATE
+#ifdef USE_IMMEDIATE
/**
* _module_imv_update - update all immediate values in the kernel
*
Index: linux-2.6-sched-devel/include/linux/module.h
===================================================================
--- linux-2.6-sched-devel.orig/include/linux/module.h 2008-05-21 15:16:52.000000000 -0400
+++ linux-2.6-sched-devel/include/linux/module.h 2008-05-21 15:16:59.000000000 -0400
@@ -339,7 +339,7 @@
/* The command line arguments (may be mangled). People like
keeping pointers to this stuff */
char *args;
-#ifdef CONFIG_IMMEDIATE
+#ifdef USE_IMMEDIATE
struct __imv *immediate;
unsigned int num_immediate;
unsigned long *immediate_cond_end;
@@ -563,7 +563,7 @@

#endif /* CONFIG_MODULES */

-#if defined(CONFIG_MODULES) && defined(CONFIG_IMMEDIATE)
+#if defined(CONFIG_MODULES) && defined(USE_IMMEDIATE)
extern void _module_imv_update(void);
extern void module_imv_update(void);
extern int is_imv_cond_end_module(unsigned long addr1, unsigned long addr2);
Index: linux-2.6-sched-devel/arch/x86/kernel/traps_32.c
===================================================================
--- linux-2.6-sched-devel.orig/arch/x86/kernel/traps_32.c 2008-05-21 15:16:06.000000000 -0400
+++ linux-2.6-sched-devel/arch/x86/kernel/traps_32.c 2008-05-21 15:16:59.000000000 -0400
@@ -595,7 +595,7 @@
}

DO_VM86_ERROR_INFO(0, SIGFPE, "divide error", divide_error, FPE_INTDIV, regs->ip)
-#if !defined(CONFIG_KPROBES) && !defined(CONFIG_IMMEDIATE)
+#if !defined(CONFIG_KPROBES) && !defined(USE_IMMEDIATE)
DO_VM86_ERROR(3, SIGTRAP, "int3", int3)
#endif
DO_VM86_ERROR(4, SIGSEGV, "overflow", overflow)
@@ -860,7 +860,7 @@
acpi_nmi_enable();
}

-#if defined(CONFIG_KPROBES) || defined(CONFIG_IMMEDIATE)
+#if defined(CONFIG_KPROBES) || defined(USE_IMMEDIATE)
void __kprobes do_int3(struct pt_regs *regs, long error_code)
{
trace_hardirqs_fixup();

--
Mathieu Desnoyers
OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F BA06 3F25 A8FE 3BAE 9A68
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