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[PATCH] uml: reuse i386 cpu-specific tuning Make UML share the underlying cpu-specific tuning done on i386. Actually, for now many config options aren't used a lot - but that can be done later. Also, UML relies on GCC optimization for things like memcpy and such more than i386, so specifying the correct -march and -mtune should be enough. Later, we may want to correct some other stuff. For instance, since FPU context switching, for us, is done (at least partially, i.e. between our kernelspace and userspace) by the host, we may allow usage of FPU operations by GCC. This doesn't hold for kernelspace vs. kernelspace, but we don't support preemption. Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 16:00:07 -07:00
# CPU tuning section - shared with UML.
# Must change only cflags-y (or [yn]), not CFLAGS! That makes a difference for UML.
[PATCH] remove gcc-2 checks Remove various things which were checking for gcc-1.x and gcc-2.x compilers. From: Adrian Bunk <bunk@stusta.de> Some documentation updates and removes some code paths for gcc < 3.2. Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 02:04:09 -07:00
#-mtune exists since gcc 3.4
[PATCH] i386: use -mcpu, not -mtune, for GCCs older than 3.4 I just noted that -mtune is used, which is only supported on recent GCCs; by reading http://gcc.gnu.org/gcc-3.4/changes.html, you see "-mcpu has been renamed to -mtune.", so for GCC < 3.4 we're not using any specific tuning in the appropriate cases. However -mcpu is deprecated, so use -mtune when possible. This was introduced by commit e9d4dce954a60dc23dd1d967766ca2347b780e54 of the old tree (between 2.6.10-rc3 and 2.6.10) by Linus Torvalds, to remove the use of -march, since that could trigger gcc using SSE on its own. But no attention was used about using -mcpu vs. -mtune. And btw, the old 2.6.4 code (for instance) was: cflags-$(CONFIG_MPENTIUMII) += $(call check_gcc,-march=pentium2,-march=i686) cflags-$(CONFIG_MPENTIUMIII) += $(call check_gcc,-march=pentium3,-march=i686) cflags-$(CONFIG_MPENTIUMM) += $(call check_gcc,-march=pentium3,-march=i686) cflags-$(CONFIG_MPENTIUM4) += $(call check_gcc,-march=pentium4,-march=i686) Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 16:00:09 -07:00
HAS_MTUNE := $(call cc-option-yn, -mtune=i386)
ifeq ($(HAS_MTUNE),y)
[PATCH] i386: Fix usage of -mtune when X86_GENERIC=y or CONFIG_MCORE2=y Hi! I sent this simple patch to lkml about two weeks ago and also cc'ed to Linus, but seems that the patch got ignored. I decided to write to you, because you have modified the relevant file most recently. Below is a copy of the mail that is also available at <http://lkml.org/lkml/2007/2/28/230>. Signed-off-by: Andi Kleen <ak@suse.de>
2007-05-02 10:27:06 -07:00
tune = $(call cc-option,-mtune=$(1),$(2))
[PATCH] i386: use -mcpu, not -mtune, for GCCs older than 3.4 I just noted that -mtune is used, which is only supported on recent GCCs; by reading http://gcc.gnu.org/gcc-3.4/changes.html, you see "-mcpu has been renamed to -mtune.", so for GCC < 3.4 we're not using any specific tuning in the appropriate cases. However -mcpu is deprecated, so use -mtune when possible. This was introduced by commit e9d4dce954a60dc23dd1d967766ca2347b780e54 of the old tree (between 2.6.10-rc3 and 2.6.10) by Linus Torvalds, to remove the use of -march, since that could trigger gcc using SSE on its own. But no attention was used about using -mcpu vs. -mtune. And btw, the old 2.6.4 code (for instance) was: cflags-$(CONFIG_MPENTIUMII) += $(call check_gcc,-march=pentium2,-march=i686) cflags-$(CONFIG_MPENTIUMIII) += $(call check_gcc,-march=pentium3,-march=i686) cflags-$(CONFIG_MPENTIUMM) += $(call check_gcc,-march=pentium3,-march=i686) cflags-$(CONFIG_MPENTIUM4) += $(call check_gcc,-march=pentium4,-march=i686) Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 16:00:09 -07:00
else
[PATCH] i386: Fix usage of -mtune when X86_GENERIC=y or CONFIG_MCORE2=y Hi! I sent this simple patch to lkml about two weeks ago and also cc'ed to Linus, but seems that the patch got ignored. I decided to write to you, because you have modified the relevant file most recently. Below is a copy of the mail that is also available at <http://lkml.org/lkml/2007/2/28/230>. Signed-off-by: Andi Kleen <ak@suse.de>
2007-05-02 10:27:06 -07:00
tune = $(call cc-option,-mcpu=$(1),$(2))
[PATCH] i386: use -mcpu, not -mtune, for GCCs older than 3.4 I just noted that -mtune is used, which is only supported on recent GCCs; by reading http://gcc.gnu.org/gcc-3.4/changes.html, you see "-mcpu has been renamed to -mtune.", so for GCC < 3.4 we're not using any specific tuning in the appropriate cases. However -mcpu is deprecated, so use -mtune when possible. This was introduced by commit e9d4dce954a60dc23dd1d967766ca2347b780e54 of the old tree (between 2.6.10-rc3 and 2.6.10) by Linus Torvalds, to remove the use of -march, since that could trigger gcc using SSE on its own. But no attention was used about using -mcpu vs. -mtune. And btw, the old 2.6.4 code (for instance) was: cflags-$(CONFIG_MPENTIUMII) += $(call check_gcc,-march=pentium2,-march=i686) cflags-$(CONFIG_MPENTIUMIII) += $(call check_gcc,-march=pentium3,-march=i686) cflags-$(CONFIG_MPENTIUMM) += $(call check_gcc,-march=pentium3,-march=i686) cflags-$(CONFIG_MPENTIUM4) += $(call check_gcc,-march=pentium4,-march=i686) Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 16:00:09 -07:00
endif
[PATCH] uml: reuse i386 cpu-specific tuning Make UML share the underlying cpu-specific tuning done on i386. Actually, for now many config options aren't used a lot - but that can be done later. Also, UML relies on GCC optimization for things like memcpy and such more than i386, so specifying the correct -march and -mtune should be enough. Later, we may want to correct some other stuff. For instance, since FPU context switching, for us, is done (at least partially, i.e. between our kernelspace and userspace) by the host, we may allow usage of FPU operations by GCC. This doesn't hold for kernelspace vs. kernelspace, but we don't support preemption. Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 16:00:07 -07:00
align := $(cc-option-align)
cflags-$(CONFIG_M386) += -march=i386
cflags-$(CONFIG_M486) += -march=i486
cflags-$(CONFIG_M586) += -march=i586
cflags-$(CONFIG_M586TSC) += -march=i586
[PATCH] remove gcc-2 checks Remove various things which were checking for gcc-1.x and gcc-2.x compilers. From: Adrian Bunk <bunk@stusta.de> Some documentation updates and removes some code paths for gcc < 3.2. Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 02:04:09 -07:00
cflags-$(CONFIG_M586MMX) += -march=pentium-mmx
[PATCH] uml: reuse i386 cpu-specific tuning Make UML share the underlying cpu-specific tuning done on i386. Actually, for now many config options aren't used a lot - but that can be done later. Also, UML relies on GCC optimization for things like memcpy and such more than i386, so specifying the correct -march and -mtune should be enough. Later, we may want to correct some other stuff. For instance, since FPU context switching, for us, is done (at least partially, i.e. between our kernelspace and userspace) by the host, we may allow usage of FPU operations by GCC. This doesn't hold for kernelspace vs. kernelspace, but we don't support preemption. Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 16:00:07 -07:00
cflags-$(CONFIG_M686) += -march=i686
[PATCH] i386: use -mcpu, not -mtune, for GCCs older than 3.4 I just noted that -mtune is used, which is only supported on recent GCCs; by reading http://gcc.gnu.org/gcc-3.4/changes.html, you see "-mcpu has been renamed to -mtune.", so for GCC < 3.4 we're not using any specific tuning in the appropriate cases. However -mcpu is deprecated, so use -mtune when possible. This was introduced by commit e9d4dce954a60dc23dd1d967766ca2347b780e54 of the old tree (between 2.6.10-rc3 and 2.6.10) by Linus Torvalds, to remove the use of -march, since that could trigger gcc using SSE on its own. But no attention was used about using -mcpu vs. -mtune. And btw, the old 2.6.4 code (for instance) was: cflags-$(CONFIG_MPENTIUMII) += $(call check_gcc,-march=pentium2,-march=i686) cflags-$(CONFIG_MPENTIUMIII) += $(call check_gcc,-march=pentium3,-march=i686) cflags-$(CONFIG_MPENTIUMM) += $(call check_gcc,-march=pentium3,-march=i686) cflags-$(CONFIG_MPENTIUM4) += $(call check_gcc,-march=pentium4,-march=i686) Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 16:00:09 -07:00
cflags-$(CONFIG_MPENTIUMII) += -march=i686 $(call tune,pentium2)
cflags-$(CONFIG_MPENTIUMIII) += -march=i686 $(call tune,pentium3)
cflags-$(CONFIG_MPENTIUMM) += -march=i686 $(call tune,pentium3)
cflags-$(CONFIG_MPENTIUM4) += -march=i686 $(call tune,pentium4)
[PATCH] uml: reuse i386 cpu-specific tuning Make UML share the underlying cpu-specific tuning done on i386. Actually, for now many config options aren't used a lot - but that can be done later. Also, UML relies on GCC optimization for things like memcpy and such more than i386, so specifying the correct -march and -mtune should be enough. Later, we may want to correct some other stuff. For instance, since FPU context switching, for us, is done (at least partially, i.e. between our kernelspace and userspace) by the host, we may allow usage of FPU operations by GCC. This doesn't hold for kernelspace vs. kernelspace, but we don't support preemption. Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 16:00:07 -07:00
cflags-$(CONFIG_MK6) += -march=k6
# Please note, that patches that add -march=athlon-xp and friends are pointless.
# They make zero difference whatsosever to performance at this time.
[PATCH] remove gcc-2 checks Remove various things which were checking for gcc-1.x and gcc-2.x compilers. From: Adrian Bunk <bunk@stusta.de> Some documentation updates and removes some code paths for gcc < 3.2. Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 02:04:09 -07:00
cflags-$(CONFIG_MK7) += -march=athlon
cflags-$(CONFIG_MK8) += $(call cc-option,-march=k8,-march=athlon)
[PATCH] uml: reuse i386 cpu-specific tuning Make UML share the underlying cpu-specific tuning done on i386. Actually, for now many config options aren't used a lot - but that can be done later. Also, UML relies on GCC optimization for things like memcpy and such more than i386, so specifying the correct -march and -mtune should be enough. Later, we may want to correct some other stuff. For instance, since FPU context switching, for us, is done (at least partially, i.e. between our kernelspace and userspace) by the host, we may allow usage of FPU operations by GCC. This doesn't hold for kernelspace vs. kernelspace, but we don't support preemption. Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 16:00:07 -07:00
cflags-$(CONFIG_MCRUSOE) += -march=i686 $(align)-functions=0 $(align)-jumps=0 $(align)-loops=0
[PATCH] i386: use -mcpu, not -mtune, for GCCs older than 3.4 I just noted that -mtune is used, which is only supported on recent GCCs; by reading http://gcc.gnu.org/gcc-3.4/changes.html, you see "-mcpu has been renamed to -mtune.", so for GCC < 3.4 we're not using any specific tuning in the appropriate cases. However -mcpu is deprecated, so use -mtune when possible. This was introduced by commit e9d4dce954a60dc23dd1d967766ca2347b780e54 of the old tree (between 2.6.10-rc3 and 2.6.10) by Linus Torvalds, to remove the use of -march, since that could trigger gcc using SSE on its own. But no attention was used about using -mcpu vs. -mtune. And btw, the old 2.6.4 code (for instance) was: cflags-$(CONFIG_MPENTIUMII) += $(call check_gcc,-march=pentium2,-march=i686) cflags-$(CONFIG_MPENTIUMIII) += $(call check_gcc,-march=pentium3,-march=i686) cflags-$(CONFIG_MPENTIUMM) += $(call check_gcc,-march=pentium3,-march=i686) cflags-$(CONFIG_MPENTIUM4) += $(call check_gcc,-march=pentium4,-march=i686) Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 16:00:09 -07:00
cflags-$(CONFIG_MEFFICEON) += -march=i686 $(call tune,pentium3) $(align)-functions=0 $(align)-jumps=0 $(align)-loops=0
[PATCH] uml: reuse i386 cpu-specific tuning Make UML share the underlying cpu-specific tuning done on i386. Actually, for now many config options aren't used a lot - but that can be done later. Also, UML relies on GCC optimization for things like memcpy and such more than i386, so specifying the correct -march and -mtune should be enough. Later, we may want to correct some other stuff. For instance, since FPU context switching, for us, is done (at least partially, i.e. between our kernelspace and userspace) by the host, we may allow usage of FPU operations by GCC. This doesn't hold for kernelspace vs. kernelspace, but we don't support preemption. Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 16:00:07 -07:00
cflags-$(CONFIG_MWINCHIPC6) += $(call cc-option,-march=winchip-c6,-march=i586)
cflags-$(CONFIG_MWINCHIP3D) += $(call cc-option,-march=winchip2,-march=i586)
cflags-$(CONFIG_MCYRIXIII) += $(call cc-option,-march=c3,-march=i486) $(align)-functions=0 $(align)-jumps=0 $(align)-loops=0
cflags-$(CONFIG_MVIAC3_2) += $(call cc-option,-march=c3-2,-march=i686)
[PATCH] i386: Add an option for the VIA C7 which sets appropriate L1 cache The VIA C7 is a 686 (with TSC) that supports MMX, SSE and SSE2, it also has a cache line length of 64 according to http://www.digit-life.com/articles2/cpu/rmma-via-c7.html. This patch sets gcc to -march=686 and select s the correct cache shift. Signed-off-by: Simon Arlott <simon@fire.lp0.eu> Signed-off-by: Andi Kleen <ak@suse.de> Cc: Andi Kleen <ak@suse.de> Cc: Dave Jones <davej@codemonkey.org.uk> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2007-05-02 10:27:05 -07:00
cflags-$(CONFIG_MVIAC7) += -march=i686
[PATCH] i386: Fix usage of -mtune when X86_GENERIC=y or CONFIG_MCORE2=y Hi! I sent this simple patch to lkml about two weeks ago and also cc'ed to Linus, but seems that the patch got ignored. I decided to write to you, because you have modified the relevant file most recently. Below is a copy of the mail that is also available at <http://lkml.org/lkml/2007/2/28/230>. Signed-off-by: Andi Kleen <ak@suse.de>
2007-05-02 10:27:06 -07:00
cflags-$(CONFIG_MCORE2) += -march=i686 $(call tune,core2)
x86: add specific support for Intel Atom architecture Add another option when selecting CPU family so the kernel can be optimized for Intel Atom CPUs. If GCC supports tuning options for Intel Atom they will be used. Signed-off-by: Tobias Doerffel <tobias.doerffel@gmail.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com> LKML-Reference: <1251018457-19157-1-git-send-email-tobias.doerffel@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-21 14:06:23 -07:00
cflags-$(CONFIG_MATOM) += $(call cc-option,-march=atom,$(call cc-option,-march=core2,-march=i686)) \
$(call cc-option,-mtune=atom,$(call cc-option,-mtune=generic))
[PATCH] uml: reuse i386 cpu-specific tuning Make UML share the underlying cpu-specific tuning done on i386. Actually, for now many config options aren't used a lot - but that can be done later. Also, UML relies on GCC optimization for things like memcpy and such more than i386, so specifying the correct -march and -mtune should be enough. Later, we may want to correct some other stuff. For instance, since FPU context switching, for us, is done (at least partially, i.e. between our kernelspace and userspace) by the host, we may allow usage of FPU operations by GCC. This doesn't hold for kernelspace vs. kernelspace, but we don't support preemption. Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 16:00:07 -07:00
# AMD Elan support
cflags-$(CONFIG_X86_ELAN) += -march=i486
# Geode GX1 support
[PATCH] remove gcc-2 checks Remove various things which were checking for gcc-1.x and gcc-2.x compilers. From: Adrian Bunk <bunk@stusta.de> Some documentation updates and removes some code paths for gcc < 3.2. Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 02:04:09 -07:00
cflags-$(CONFIG_MGEODEGX1) += -march=pentium-mmx
[PATCH] uml: reuse i386 cpu-specific tuning Make UML share the underlying cpu-specific tuning done on i386. Actually, for now many config options aren't used a lot - but that can be done later. Also, UML relies on GCC optimization for things like memcpy and such more than i386, so specifying the correct -march and -mtune should be enough. Later, we may want to correct some other stuff. For instance, since FPU context switching, for us, is done (at least partially, i.e. between our kernelspace and userspace) by the host, we may allow usage of FPU operations by GCC. This doesn't hold for kernelspace vs. kernelspace, but we don't support preemption. Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 16:00:07 -07:00
[PATCH] x86-64: Use -mtune=generic for generic kernels The upcomming gcc 4.2 got a new option -mtune=generic to tune code for both common AMD and Intel CPUs. Use this option when available for generic kernels. On x86-64 it is used with CONFIG_GENERIC_CPU. On i386 it is enabled with CONFIG_X86_GENERIC. It won't affect the base line CPU support in any ways and also not the minimum supported CPU. Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-25 08:29:06 -07:00
# add at the end to overwrite eventual tuning options from earlier
# cpu entries
[PATCH] i386: Fix usage of -mtune when X86_GENERIC=y or CONFIG_MCORE2=y Hi! I sent this simple patch to lkml about two weeks ago and also cc'ed to Linus, but seems that the patch got ignored. I decided to write to you, because you have modified the relevant file most recently. Below is a copy of the mail that is also available at <http://lkml.org/lkml/2007/2/28/230>. Signed-off-by: Andi Kleen <ak@suse.de>
2007-05-02 10:27:06 -07:00
cflags-$(CONFIG_X86_GENERIC) += $(call tune,generic,$(call tune,i686))
[PATCH] x86-64: Use -mtune=generic for generic kernels The upcomming gcc 4.2 got a new option -mtune=generic to tune code for both common AMD and Intel CPUs. Use this option when available for generic kernels. On x86-64 it is used with CONFIG_GENERIC_CPU. On i386 it is enabled with CONFIG_X86_GENERIC. It won't affect the base line CPU support in any ways and also not the minimum supported CPU. Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-25 08:29:06 -07:00
x86: Prevent GCC 4.4.x (pentium-mmx et al) function prologue wreckage When the kernel is compiled with -pg for tracing GCC 4.4.x inserts stack alignment of a function _before_ the mcount prologue if the -march=pentium-mmx is set and -mtune=generic is not set. This breaks the assumption of the function graph tracer which expects that the mcount prologue push %ebp mov %esp, %ebp is the first stack operation in a function because it needs to modify the function return address on the stack to trap into the tracer before returning to the real caller. The generated code is: push %edi lea 0x8(%esp),%edi and $0xfffffff0,%esp pushl -0x4(%edi) push %ebp mov %esp,%ebp so the tracer modifies the copy of the return address which is stored after the stack alignment and therefor does not trap the return which in turn breaks the call chain logic of the tracer and leads to a kernel panic. Aside of the fact that the generated code is horrible for no good reason other -march -mtune options generate the expected: push %ebp mov %esp,%ebp and $0xfffffff0,%esp which does the same and keeps everything intact. After some experimenting we found out that this problem is restricted to gcc4.4.x and to the following -march settings: i586, pentium, pentium-mmx, k6, k6-2, k6-3, winchip-c6, winchip2, c3, geode By adding -mtune=generic the code generator produces always the expected code. So forcing -mtune=generic when CONFIG_FUNCTION_GRAPH_TRACER=y is not pretty, but at the moment the only way to prevent that the kernel trips over gcc-shrooms induced code madness. Most distro kernels have CONFIG_X86_GENERIC=y anyway which forces -mtune=generic as well so it will not impact those. References: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42109 http://lkml.org/lkml/2009/11/19/17 Signed-off-by: Thomas Gleixner <tglx@linutronix.de> LKML-Reference: <alpine.LFD.2.00.0911200206570.24119@localhost.localdomain> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <peterz@infradead.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com>, Cc: Jeff Law <law@redhat.com> Cc: gcc@gcc.gnu.org Cc: David Daney <ddaney@caviumnetworks.com> Cc: Andrew Haley <aph@redhat.com> Cc: Richard Guenther <richard.guenther@gmail.com> Cc: stable@kernel.org
2009-11-20 04:01:43 -07:00
# Work around the pentium-mmx code generator madness of gcc4.4.x which
# does stack alignment by generating horrible code _before_ the mcount
# prologue (push %ebp, mov %esp, %ebp) which breaks the function graph
# tracer assumptions
cflags-$(CONFIG_FUNCTION_GRAPH_TRACER) += $(call cc-option,-mtune=generic)
x86: prevent binutils from being "smart" and generating NOPLs for us binutils, contrary to documented behaviour, will generate long NOPs (a P6-or-higher instruction which is broken on at least some VIA chips, Virtual PC/Virtual Server, and some versions of Qemu) depending on the -mtune= option, which is not supposed to change architectural behaviour. Pass an explicit override to the assembler, in case ends up passing the -mtune= parameter to gas (gcc 4.3.0 does not appear to.) Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-09-08 12:01:48 -07:00
# Bug fix for binutils: this option is required in order to keep
# binutils from generating NOPL instructions against our will.
ifneq ($(CONFIG_X86_P6_NOP),y)
cflags-y += $(call cc-option,-Wa$(comma)-mtune=generic32,)
endif
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