[tip: sched/core] cpuidle, mwait: Make the mwait code noinstr clean

From: tip-bot2 for Peter Zijlstra
Date: Fri Jan 13 2023 - 07:35:25 EST


The following commit has been merged into the sched/core branch of tip:

Commit-ID: 2ec8efe64e6dfcaa50906ae4b0b5a0a7e1a54d50
Gitweb: https://git.kernel.org/tip/2ec8efe64e6dfcaa50906ae4b0b5a0a7e1a54d50
Author: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
AuthorDate: Thu, 12 Jan 2023 20:43:42 +01:00
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitterDate: Fri, 13 Jan 2023 11:48:16 +01:00

cpuidle, mwait: Make the mwait code noinstr clean

objtool found a few cases where this code called out into instrumented
code:

vmlinux.o: warning: objtool: intel_idle_s2idle+0x6e: call to __monitor.constprop.0() leaves .noinstr.text section
vmlinux.o: warning: objtool: intel_idle_irq+0x8c: call to __monitor.constprop.0() leaves .noinstr.text section
vmlinux.o: warning: objtool: intel_idle+0x73: call to __monitor.constprop.0() leaves .noinstr.text section

vmlinux.o: warning: objtool: mwait_idle+0x88: call to clflush() leaves .noinstr.text section

Fix it by marking the affected methods as __always_inline.

Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
Tested-by: Tony Lindgren <tony@xxxxxxxxxxx>
Tested-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Acked-by: Frederic Weisbecker <frederic@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20230112195541.050542952@xxxxxxxxxxxxx
---
arch/x86/include/asm/mwait.h | 12 ++++++------
arch/x86/include/asm/special_insns.h | 2 +-
2 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/arch/x86/include/asm/mwait.h b/arch/x86/include/asm/mwait.h
index f224216..778df05 100644
--- a/arch/x86/include/asm/mwait.h
+++ b/arch/x86/include/asm/mwait.h
@@ -26,7 +26,7 @@
#define TPAUSE_C01_STATE 1
#define TPAUSE_C02_STATE 0

-static inline void __monitor(const void *eax, unsigned long ecx,
+static __always_inline void __monitor(const void *eax, unsigned long ecx,
unsigned long edx)
{
/* "monitor %eax, %ecx, %edx;" */
@@ -34,7 +34,7 @@ static inline void __monitor(const void *eax, unsigned long ecx,
:: "a" (eax), "c" (ecx), "d"(edx));
}

-static inline void __monitorx(const void *eax, unsigned long ecx,
+static __always_inline void __monitorx(const void *eax, unsigned long ecx,
unsigned long edx)
{
/* "monitorx %eax, %ecx, %edx;" */
@@ -42,7 +42,7 @@ static inline void __monitorx(const void *eax, unsigned long ecx,
:: "a" (eax), "c" (ecx), "d"(edx));
}

-static inline void __mwait(unsigned long eax, unsigned long ecx)
+static __always_inline void __mwait(unsigned long eax, unsigned long ecx)
{
mds_idle_clear_cpu_buffers();

@@ -77,8 +77,8 @@ static inline void __mwait(unsigned long eax, unsigned long ecx)
* EAX (logical) address to monitor
* ECX #GP if not zero
*/
-static inline void __mwaitx(unsigned long eax, unsigned long ebx,
- unsigned long ecx)
+static __always_inline void __mwaitx(unsigned long eax, unsigned long ebx,
+ unsigned long ecx)
{
/* No MDS buffer clear as this is AMD/HYGON only */

@@ -87,7 +87,7 @@ static inline void __mwaitx(unsigned long eax, unsigned long ebx,
:: "a" (eax), "b" (ebx), "c" (ecx));
}

-static inline void __sti_mwait(unsigned long eax, unsigned long ecx)
+static __always_inline void __sti_mwait(unsigned long eax, unsigned long ecx)
{
mds_idle_clear_cpu_buffers();
/* "mwait %eax, %ecx;" */
diff --git a/arch/x86/include/asm/special_insns.h b/arch/x86/include/asm/special_insns.h
index c2e3221..54621e7 100644
--- a/arch/x86/include/asm/special_insns.h
+++ b/arch/x86/include/asm/special_insns.h
@@ -196,7 +196,7 @@ static inline void load_gs_index(unsigned int selector)

#endif /* CONFIG_PARAVIRT_XXL */

-static inline void clflush(volatile void *__p)
+static __always_inline void clflush(volatile void *__p)
{
asm volatile("clflush %0" : "+m" (*(volatile char __force *)__p));
}