* [PATCH 0/3] x86: do not save callee-preserved registers around lockdep_sys_exit_thunk
@ 2015-03-25 20:14 Denys Vlasenko
2015-03-25 20:14 ` [PATCH 1/3] x86: move ARCH_LOCKDEP_SYS_EXIT[IRQ] defines closer to their users Denys Vlasenko
` (2 more replies)
0 siblings, 3 replies; 7+ messages in thread
From: Denys Vlasenko @ 2015-03-25 20:14 UTC (permalink / raw)
To: Ingo Molnar
Cc: Denys Vlasenko, Linus Torvalds, Steven Rostedt, Borislav Petkov,
H. Peter Anvin, Andy Lutomirski, Oleg Nesterov,
Frederic Weisbecker, Alexei Starovoitov, Will Drewry, Kees Cook,
x86, linux-kernel
Recent change to struct pt_regs handling in entry.S, among other things,
changed how callee-preserved registers are saved around call
to lockdep_sys_exit_thunk:
# define LOCKDEP_SYS_EXIT_IRQ \
TRACE_IRQS_ON; \
sti; \
SAVE_EXTRA_REGS; \ <======= HERE
LOCKDEP_SYS_EXIT; \
RESTORE_EXTRA_REGS; \ <======= HERE
The change is in fact a bit fragile:
now we assume that LOCKDEP_SYS_EXIT_IRQ macro is used only
when there is a struct pt_regs on the stack.
So far this assumption is true, but it is probably a coincidence.
We can revert back to pushing registers, but this callee-preserved registers
saving appears bogus. It is not necessary: they _are_ callee-preserved,
and lockdep_sys_exit() does not touch them on the stack either.
First two patches clean up #define maze so that we can see
that LOCKDEP_SYS_EXIT macro call above is merely "call lockdep_sys_exit_thunk".
Last patch removes SAVE/RESTORE.
I tested this patch series and everything seems to run fine
on a lockdep-enabled kernel with these lines removed.
Denys Vlasenko (3):
x86: move ARCH_LOCKDEP_SYS_EXIT[IRQ] defines closer to their users
x86: fold ARCH_LOCKDEP_SYS_EXIT defines into their users
x86: do not save callee-preserved registers around lockdep_sys_exit_thunk
arch/x86/include/asm/irqflags.h | 45 +++++++++++++++++------------------------
1 file changed, 19 insertions(+), 26 deletions(-)
CC: Linus Torvalds <torvalds@linux-foundation.org>
CC: Steven Rostedt <rostedt@goodmis.org>
CC: Ingo Molnar <mingo@kernel.org>
CC: Borislav Petkov <bp@alien8.de>
CC: "H. Peter Anvin" <hpa@zytor.com>
CC: Andy Lutomirski <luto@amacapital.net>
CC: Oleg Nesterov <oleg@redhat.com>
CC: Frederic Weisbecker <fweisbec@gmail.com>
CC: Alexei Starovoitov <ast@plumgrid.com>
CC: Will Drewry <wad@chromium.org>
CC: Kees Cook <keescook@chromium.org>
CC: x86@kernel.org
CC: linux-kernel@vger.kernel.org
--
1.8.1.4
^ permalink raw reply [flat|nested] 7+ messages in thread
* [PATCH 1/3] x86: move ARCH_LOCKDEP_SYS_EXIT[IRQ] defines closer to their users
2015-03-25 20:14 [PATCH 0/3] x86: do not save callee-preserved registers around lockdep_sys_exit_thunk Denys Vlasenko
@ 2015-03-25 20:14 ` Denys Vlasenko
2015-03-27 11:47 ` [tip:x86/asm] x86/irq/tracing: Move ARCH_LOCKDEP_SYS_EXIT " tip-bot for Denys Vlasenko
2015-03-25 20:14 ` [PATCH 2/3] x86: fold ARCH_LOCKDEP_SYS_EXIT defines into " Denys Vlasenko
2015-03-25 20:14 ` [PATCH 3/3] x86: do not save callee-preserved registers around lockdep_sys_exit_thunk Denys Vlasenko
2 siblings, 1 reply; 7+ messages in thread
From: Denys Vlasenko @ 2015-03-25 20:14 UTC (permalink / raw)
To: Ingo Molnar
Cc: Denys Vlasenko, Linus Torvalds, Steven Rostedt, Borislav Petkov,
H. Peter Anvin, Andy Lutomirski, Oleg Nesterov,
Frederic Weisbecker, Alexei Starovoitov, Will Drewry, Kees Cook,
x86, linux-kernel
This change simply moves defines around (even if it's not obvious in a patch form).
Nothing is changed.
This is a preparation for folding ARCH_LOCKDEP_SYS_EXIT defines into their users.
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
CC: Linus Torvalds <torvalds@linux-foundation.org>
CC: Steven Rostedt <rostedt@goodmis.org>
CC: Ingo Molnar <mingo@kernel.org>
CC: Borislav Petkov <bp@alien8.de>
CC: "H. Peter Anvin" <hpa@zytor.com>
CC: Andy Lutomirski <luto@amacapital.net>
CC: Oleg Nesterov <oleg@redhat.com>
CC: Frederic Weisbecker <fweisbec@gmail.com>
CC: Alexei Starovoitov <ast@plumgrid.com>
CC: Will Drewry <wad@chromium.org>
CC: Kees Cook <keescook@chromium.org>
CC: x86@kernel.org
CC: linux-kernel@vger.kernel.org
---
arch/x86/include/asm/irqflags.h | 37 +++++++++++++++++--------------------
1 file changed, 17 insertions(+), 20 deletions(-)
diff --git a/arch/x86/include/asm/irqflags.h b/arch/x86/include/asm/irqflags.h
index 021bee9..55866c2 100644
--- a/arch/x86/include/asm/irqflags.h
+++ b/arch/x86/include/asm/irqflags.h
@@ -163,12 +163,20 @@ static inline int arch_irqs_disabled(void)
return arch_irqs_disabled_flags(flags);
}
+#endif /* !__ASSEMBLY__ */
+#ifdef __ASSEMBLY__
+#ifdef CONFIG_TRACE_IRQFLAGS
+# define TRACE_IRQS_ON call trace_hardirqs_on_thunk;
+# define TRACE_IRQS_OFF call trace_hardirqs_off_thunk;
#else
-
-#ifdef CONFIG_X86_64
-#define ARCH_LOCKDEP_SYS_EXIT call lockdep_sys_exit_thunk
-#define ARCH_LOCKDEP_SYS_EXIT_IRQ \
+# define TRACE_IRQS_ON
+# define TRACE_IRQS_OFF
+#endif
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+# ifdef CONFIG_X86_64
+# define ARCH_LOCKDEP_SYS_EXIT call lockdep_sys_exit_thunk
+# define ARCH_LOCKDEP_SYS_EXIT_IRQ \
TRACE_IRQS_ON; \
sti; \
SAVE_EXTRA_REGS; \
@@ -176,9 +184,8 @@ static inline int arch_irqs_disabled(void)
RESTORE_EXTRA_REGS; \
cli; \
TRACE_IRQS_OFF;
-
-#else
-#define ARCH_LOCKDEP_SYS_EXIT \
+# else
+# define ARCH_LOCKDEP_SYS_EXIT \
pushl %eax; \
pushl %ecx; \
pushl %edx; \
@@ -186,24 +193,14 @@ static inline int arch_irqs_disabled(void)
popl %edx; \
popl %ecx; \
popl %eax;
-
-#define ARCH_LOCKDEP_SYS_EXIT_IRQ
-#endif
-
-#ifdef CONFIG_TRACE_IRQFLAGS
-# define TRACE_IRQS_ON call trace_hardirqs_on_thunk;
-# define TRACE_IRQS_OFF call trace_hardirqs_off_thunk;
-#else
-# define TRACE_IRQS_ON
-# define TRACE_IRQS_OFF
-#endif
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
+# define ARCH_LOCKDEP_SYS_EXIT_IRQ
+# endif
# define LOCKDEP_SYS_EXIT ARCH_LOCKDEP_SYS_EXIT
# define LOCKDEP_SYS_EXIT_IRQ ARCH_LOCKDEP_SYS_EXIT_IRQ
# else
# define LOCKDEP_SYS_EXIT
# define LOCKDEP_SYS_EXIT_IRQ
# endif
-
#endif /* __ASSEMBLY__ */
+
#endif
--
1.8.1.4
^ permalink raw reply [flat|nested] 7+ messages in thread
* [PATCH 2/3] x86: fold ARCH_LOCKDEP_SYS_EXIT defines into their users
2015-03-25 20:14 [PATCH 0/3] x86: do not save callee-preserved registers around lockdep_sys_exit_thunk Denys Vlasenko
2015-03-25 20:14 ` [PATCH 1/3] x86: move ARCH_LOCKDEP_SYS_EXIT[IRQ] defines closer to their users Denys Vlasenko
@ 2015-03-25 20:14 ` Denys Vlasenko
2015-03-27 11:47 ` [tip:x86/asm] x86/irq/tracing: Fold " tip-bot for Denys Vlasenko
2015-03-25 20:14 ` [PATCH 3/3] x86: do not save callee-preserved registers around lockdep_sys_exit_thunk Denys Vlasenko
2 siblings, 1 reply; 7+ messages in thread
From: Denys Vlasenko @ 2015-03-25 20:14 UTC (permalink / raw)
To: Ingo Molnar
Cc: Denys Vlasenko, Linus Torvalds, Steven Rostedt, Borislav Petkov,
H. Peter Anvin, Andy Lutomirski, Oleg Nesterov,
Frederic Weisbecker, Alexei Starovoitov, Will Drewry, Kees Cook,
x86, linux-kernel
There is no need to have an extra level of macro indirection here.
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
CC: Linus Torvalds <torvalds@linux-foundation.org>
CC: Steven Rostedt <rostedt@goodmis.org>
CC: Ingo Molnar <mingo@kernel.org>
CC: Borislav Petkov <bp@alien8.de>
CC: "H. Peter Anvin" <hpa@zytor.com>
CC: Andy Lutomirski <luto@amacapital.net>
CC: Oleg Nesterov <oleg@redhat.com>
CC: Frederic Weisbecker <fweisbec@gmail.com>
CC: Alexei Starovoitov <ast@plumgrid.com>
CC: Will Drewry <wad@chromium.org>
CC: Kees Cook <keescook@chromium.org>
CC: x86@kernel.org
CC: linux-kernel@vger.kernel.org
---
arch/x86/include/asm/irqflags.h | 16 +++++++---------
1 file changed, 7 insertions(+), 9 deletions(-)
diff --git a/arch/x86/include/asm/irqflags.h b/arch/x86/include/asm/irqflags.h
index 55866c2..19355f3 100644
--- a/arch/x86/include/asm/irqflags.h
+++ b/arch/x86/include/asm/irqflags.h
@@ -175,17 +175,17 @@ static inline int arch_irqs_disabled(void)
#endif
#ifdef CONFIG_DEBUG_LOCK_ALLOC
# ifdef CONFIG_X86_64
-# define ARCH_LOCKDEP_SYS_EXIT call lockdep_sys_exit_thunk
-# define ARCH_LOCKDEP_SYS_EXIT_IRQ \
+# define LOCKDEP_SYS_EXIT call lockdep_sys_exit_thunk
+# define LOCKDEP_SYS_EXIT_IRQ \
TRACE_IRQS_ON; \
sti; \
SAVE_EXTRA_REGS; \
- LOCKDEP_SYS_EXIT; \
+ call lockdep_sys_exit_thunk; \
RESTORE_EXTRA_REGS; \
cli; \
TRACE_IRQS_OFF;
# else
-# define ARCH_LOCKDEP_SYS_EXIT \
+# define LOCKDEP_SYS_EXIT \
pushl %eax; \
pushl %ecx; \
pushl %edx; \
@@ -193,14 +193,12 @@ static inline int arch_irqs_disabled(void)
popl %edx; \
popl %ecx; \
popl %eax;
-# define ARCH_LOCKDEP_SYS_EXIT_IRQ
+# define LOCKDEP_SYS_EXIT_IRQ
# endif
-# define LOCKDEP_SYS_EXIT ARCH_LOCKDEP_SYS_EXIT
-# define LOCKDEP_SYS_EXIT_IRQ ARCH_LOCKDEP_SYS_EXIT_IRQ
-# else
+#else
# define LOCKDEP_SYS_EXIT
# define LOCKDEP_SYS_EXIT_IRQ
-# endif
+#endif
#endif /* __ASSEMBLY__ */
#endif
--
1.8.1.4
^ permalink raw reply [flat|nested] 7+ messages in thread
* [PATCH 3/3] x86: do not save callee-preserved registers around lockdep_sys_exit_thunk
2015-03-25 20:14 [PATCH 0/3] x86: do not save callee-preserved registers around lockdep_sys_exit_thunk Denys Vlasenko
2015-03-25 20:14 ` [PATCH 1/3] x86: move ARCH_LOCKDEP_SYS_EXIT[IRQ] defines closer to their users Denys Vlasenko
2015-03-25 20:14 ` [PATCH 2/3] x86: fold ARCH_LOCKDEP_SYS_EXIT defines into " Denys Vlasenko
@ 2015-03-25 20:14 ` Denys Vlasenko
2015-03-27 11:47 ` [tip:x86/asm] x86/irq/tracing: Do " tip-bot for Denys Vlasenko
2 siblings, 1 reply; 7+ messages in thread
From: Denys Vlasenko @ 2015-03-25 20:14 UTC (permalink / raw)
To: Ingo Molnar
Cc: Denys Vlasenko, Linus Torvalds, Steven Rostedt, Borislav Petkov,
H. Peter Anvin, Andy Lutomirski, Oleg Nesterov,
Frederic Weisbecker, Alexei Starovoitov, Will Drewry, Kees Cook,
x86, linux-kernel
Internally, lockdep_sys_exit_thunk saves callee-clobbered registers,
and calls a C function, lockdep_sys_exit. Thus, callee-preserved registers
won't be mangled, there is no need to save them.
Patch was run-tested.
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
CC: Linus Torvalds <torvalds@linux-foundation.org>
CC: Steven Rostedt <rostedt@goodmis.org>
CC: Ingo Molnar <mingo@kernel.org>
CC: Borislav Petkov <bp@alien8.de>
CC: "H. Peter Anvin" <hpa@zytor.com>
CC: Andy Lutomirski <luto@amacapital.net>
CC: Oleg Nesterov <oleg@redhat.com>
CC: Frederic Weisbecker <fweisbec@gmail.com>
CC: Alexei Starovoitov <ast@plumgrid.com>
CC: Will Drewry <wad@chromium.org>
CC: Kees Cook <keescook@chromium.org>
CC: x86@kernel.org
CC: linux-kernel@vger.kernel.org
---
arch/x86/include/asm/irqflags.h | 2 --
1 file changed, 2 deletions(-)
diff --git a/arch/x86/include/asm/irqflags.h b/arch/x86/include/asm/irqflags.h
index 19355f3..9a63eae 100644
--- a/arch/x86/include/asm/irqflags.h
+++ b/arch/x86/include/asm/irqflags.h
@@ -179,9 +179,7 @@ static inline int arch_irqs_disabled(void)
# define LOCKDEP_SYS_EXIT_IRQ \
TRACE_IRQS_ON; \
sti; \
- SAVE_EXTRA_REGS; \
call lockdep_sys_exit_thunk; \
- RESTORE_EXTRA_REGS; \
cli; \
TRACE_IRQS_OFF;
# else
--
1.8.1.4
^ permalink raw reply [flat|nested] 7+ messages in thread
* [tip:x86/asm] x86/irq/tracing: Move ARCH_LOCKDEP_SYS_EXIT defines closer to their users
2015-03-25 20:14 ` [PATCH 1/3] x86: move ARCH_LOCKDEP_SYS_EXIT[IRQ] defines closer to their users Denys Vlasenko
@ 2015-03-27 11:47 ` tip-bot for Denys Vlasenko
0 siblings, 0 replies; 7+ messages in thread
From: tip-bot for Denys Vlasenko @ 2015-03-27 11:47 UTC (permalink / raw)
To: linux-tip-commits
Cc: mingo, oleg, wad, tglx, fweisbec, ast, torvalds, bp,
linux-kernel, rostedt, dvlasenk, keescook, hpa, luto
Commit-ID: 40e2ec657dcb0ae328db1abc8e37df4caa893391
Gitweb: http://git.kernel.org/tip/40e2ec657dcb0ae328db1abc8e37df4caa893391
Author: Denys Vlasenko <dvlasenk@redhat.com>
AuthorDate: Wed, 25 Mar 2015 21:14:26 +0100
Committer: Ingo Molnar <mingo@kernel.org>
CommitDate: Fri, 27 Mar 2015 10:01:48 +0100
x86/irq/tracing: Move ARCH_LOCKDEP_SYS_EXIT defines closer to their users
This change simply moves defines around (even if it's not
obvious in a patch form). Nothing is changed.
This is a preparation for folding ARCH_LOCKDEP_SYS_EXIT defines
into their users.
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1427314468-12763-2-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
arch/x86/include/asm/irqflags.h | 37 +++++++++++++++++--------------------
1 file changed, 17 insertions(+), 20 deletions(-)
diff --git a/arch/x86/include/asm/irqflags.h b/arch/x86/include/asm/irqflags.h
index 021bee9..55866c2 100644
--- a/arch/x86/include/asm/irqflags.h
+++ b/arch/x86/include/asm/irqflags.h
@@ -163,12 +163,20 @@ static inline int arch_irqs_disabled(void)
return arch_irqs_disabled_flags(flags);
}
+#endif /* !__ASSEMBLY__ */
+#ifdef __ASSEMBLY__
+#ifdef CONFIG_TRACE_IRQFLAGS
+# define TRACE_IRQS_ON call trace_hardirqs_on_thunk;
+# define TRACE_IRQS_OFF call trace_hardirqs_off_thunk;
#else
-
-#ifdef CONFIG_X86_64
-#define ARCH_LOCKDEP_SYS_EXIT call lockdep_sys_exit_thunk
-#define ARCH_LOCKDEP_SYS_EXIT_IRQ \
+# define TRACE_IRQS_ON
+# define TRACE_IRQS_OFF
+#endif
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+# ifdef CONFIG_X86_64
+# define ARCH_LOCKDEP_SYS_EXIT call lockdep_sys_exit_thunk
+# define ARCH_LOCKDEP_SYS_EXIT_IRQ \
TRACE_IRQS_ON; \
sti; \
SAVE_EXTRA_REGS; \
@@ -176,9 +184,8 @@ static inline int arch_irqs_disabled(void)
RESTORE_EXTRA_REGS; \
cli; \
TRACE_IRQS_OFF;
-
-#else
-#define ARCH_LOCKDEP_SYS_EXIT \
+# else
+# define ARCH_LOCKDEP_SYS_EXIT \
pushl %eax; \
pushl %ecx; \
pushl %edx; \
@@ -186,24 +193,14 @@ static inline int arch_irqs_disabled(void)
popl %edx; \
popl %ecx; \
popl %eax;
-
-#define ARCH_LOCKDEP_SYS_EXIT_IRQ
-#endif
-
-#ifdef CONFIG_TRACE_IRQFLAGS
-# define TRACE_IRQS_ON call trace_hardirqs_on_thunk;
-# define TRACE_IRQS_OFF call trace_hardirqs_off_thunk;
-#else
-# define TRACE_IRQS_ON
-# define TRACE_IRQS_OFF
-#endif
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
+# define ARCH_LOCKDEP_SYS_EXIT_IRQ
+# endif
# define LOCKDEP_SYS_EXIT ARCH_LOCKDEP_SYS_EXIT
# define LOCKDEP_SYS_EXIT_IRQ ARCH_LOCKDEP_SYS_EXIT_IRQ
# else
# define LOCKDEP_SYS_EXIT
# define LOCKDEP_SYS_EXIT_IRQ
# endif
-
#endif /* __ASSEMBLY__ */
+
#endif
^ permalink raw reply [flat|nested] 7+ messages in thread
* [tip:x86/asm] x86/irq/tracing: Fold ARCH_LOCKDEP_SYS_EXIT defines into their users
2015-03-25 20:14 ` [PATCH 2/3] x86: fold ARCH_LOCKDEP_SYS_EXIT defines into " Denys Vlasenko
@ 2015-03-27 11:47 ` tip-bot for Denys Vlasenko
0 siblings, 0 replies; 7+ messages in thread
From: tip-bot for Denys Vlasenko @ 2015-03-27 11:47 UTC (permalink / raw)
To: linux-tip-commits
Cc: luto, oleg, rostedt, bp, dvlasenk, torvalds, hpa, ast, fweisbec,
keescook, tglx, wad, mingo, linux-kernel
Commit-ID: 7dc7cc0780b04935f1127fa22ee23e9d6daf166a
Gitweb: http://git.kernel.org/tip/7dc7cc0780b04935f1127fa22ee23e9d6daf166a
Author: Denys Vlasenko <dvlasenk@redhat.com>
AuthorDate: Wed, 25 Mar 2015 21:14:27 +0100
Committer: Ingo Molnar <mingo@kernel.org>
CommitDate: Fri, 27 Mar 2015 10:01:49 +0100
x86/irq/tracing: Fold ARCH_LOCKDEP_SYS_EXIT defines into their users
There is no need to have an extra level of macro indirection
here.
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1427314468-12763-3-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
arch/x86/include/asm/irqflags.h | 16 +++++++---------
1 file changed, 7 insertions(+), 9 deletions(-)
diff --git a/arch/x86/include/asm/irqflags.h b/arch/x86/include/asm/irqflags.h
index 55866c2..19355f3 100644
--- a/arch/x86/include/asm/irqflags.h
+++ b/arch/x86/include/asm/irqflags.h
@@ -175,17 +175,17 @@ static inline int arch_irqs_disabled(void)
#endif
#ifdef CONFIG_DEBUG_LOCK_ALLOC
# ifdef CONFIG_X86_64
-# define ARCH_LOCKDEP_SYS_EXIT call lockdep_sys_exit_thunk
-# define ARCH_LOCKDEP_SYS_EXIT_IRQ \
+# define LOCKDEP_SYS_EXIT call lockdep_sys_exit_thunk
+# define LOCKDEP_SYS_EXIT_IRQ \
TRACE_IRQS_ON; \
sti; \
SAVE_EXTRA_REGS; \
- LOCKDEP_SYS_EXIT; \
+ call lockdep_sys_exit_thunk; \
RESTORE_EXTRA_REGS; \
cli; \
TRACE_IRQS_OFF;
# else
-# define ARCH_LOCKDEP_SYS_EXIT \
+# define LOCKDEP_SYS_EXIT \
pushl %eax; \
pushl %ecx; \
pushl %edx; \
@@ -193,14 +193,12 @@ static inline int arch_irqs_disabled(void)
popl %edx; \
popl %ecx; \
popl %eax;
-# define ARCH_LOCKDEP_SYS_EXIT_IRQ
+# define LOCKDEP_SYS_EXIT_IRQ
# endif
-# define LOCKDEP_SYS_EXIT ARCH_LOCKDEP_SYS_EXIT
-# define LOCKDEP_SYS_EXIT_IRQ ARCH_LOCKDEP_SYS_EXIT_IRQ
-# else
+#else
# define LOCKDEP_SYS_EXIT
# define LOCKDEP_SYS_EXIT_IRQ
-# endif
+#endif
#endif /* __ASSEMBLY__ */
#endif
^ permalink raw reply [flat|nested] 7+ messages in thread
* [tip:x86/asm] x86/irq/tracing: Do not save callee-preserved registers around lockdep_sys_exit_thunk
2015-03-25 20:14 ` [PATCH 3/3] x86: do not save callee-preserved registers around lockdep_sys_exit_thunk Denys Vlasenko
@ 2015-03-27 11:47 ` tip-bot for Denys Vlasenko
0 siblings, 0 replies; 7+ messages in thread
From: tip-bot for Denys Vlasenko @ 2015-03-27 11:47 UTC (permalink / raw)
To: linux-tip-commits
Cc: mingo, rostedt, wad, linux-kernel, fweisbec, hpa, dvlasenk, bp,
luto, ast, keescook, oleg, tglx, torvalds
Commit-ID: aa6d9a128b861fe7e9dc37bcc37179837674b739
Gitweb: http://git.kernel.org/tip/aa6d9a128b861fe7e9dc37bcc37179837674b739
Author: Denys Vlasenko <dvlasenk@redhat.com>
AuthorDate: Wed, 25 Mar 2015 21:14:28 +0100
Committer: Ingo Molnar <mingo@kernel.org>
CommitDate: Fri, 27 Mar 2015 10:01:49 +0100
x86/irq/tracing: Do not save callee-preserved registers around lockdep_sys_exit_thunk
Internally, lockdep_sys_exit_thunk saves callee-clobbered
registers, and calls a C function, lockdep_sys_exit. Thus,
callee-preserved registers won't be mangled, there is no need to
save them.
Patch was run-tested.
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1427314468-12763-4-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
arch/x86/include/asm/irqflags.h | 2 --
1 file changed, 2 deletions(-)
diff --git a/arch/x86/include/asm/irqflags.h b/arch/x86/include/asm/irqflags.h
index 19355f3..9a63eae 100644
--- a/arch/x86/include/asm/irqflags.h
+++ b/arch/x86/include/asm/irqflags.h
@@ -179,9 +179,7 @@ static inline int arch_irqs_disabled(void)
# define LOCKDEP_SYS_EXIT_IRQ \
TRACE_IRQS_ON; \
sti; \
- SAVE_EXTRA_REGS; \
call lockdep_sys_exit_thunk; \
- RESTORE_EXTRA_REGS; \
cli; \
TRACE_IRQS_OFF;
# else
^ permalink raw reply [flat|nested] 7+ messages in thread
end of thread, other threads:[~2015-03-27 11:48 UTC | newest]
Thread overview: 7+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2015-03-25 20:14 [PATCH 0/3] x86: do not save callee-preserved registers around lockdep_sys_exit_thunk Denys Vlasenko
2015-03-25 20:14 ` [PATCH 1/3] x86: move ARCH_LOCKDEP_SYS_EXIT[IRQ] defines closer to their users Denys Vlasenko
2015-03-27 11:47 ` [tip:x86/asm] x86/irq/tracing: Move ARCH_LOCKDEP_SYS_EXIT " tip-bot for Denys Vlasenko
2015-03-25 20:14 ` [PATCH 2/3] x86: fold ARCH_LOCKDEP_SYS_EXIT defines into " Denys Vlasenko
2015-03-27 11:47 ` [tip:x86/asm] x86/irq/tracing: Fold " tip-bot for Denys Vlasenko
2015-03-25 20:14 ` [PATCH 3/3] x86: do not save callee-preserved registers around lockdep_sys_exit_thunk Denys Vlasenko
2015-03-27 11:47 ` [tip:x86/asm] x86/irq/tracing: Do " tip-bot for Denys Vlasenko
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
Powered by JetHome