From a94d342b9cb09edfe888ea972af0883b6a8d992b Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Wed, 30 Oct 2013 11:42:46 +0100 Subject: [PATCH] tools/perf: Add required memory barriers To match patch bf378d341e48 ("perf: Fix perf ring buffer memory ordering") change userspace to also adhere to the ordering outlined. Signed-off-by: Peter Zijlstra Cc: Michael Neuling Cc: "Paul E. McKenney" Cc: james.hogan@imgtec.com Cc: Vince Weaver Cc: Victor Kaplansky Cc: Oleg Nesterov Cc: Anton Blanchard Cc: Benjamin Herrenschmidt Cc: Frederic Weisbecker Cc: Mathieu Desnoyers Cc: Michael Ellerman Link: http://lkml.kernel.org/r/20131030104246.GH16117@laptop.programming.kicks-ass.net Signed-off-by: Ingo Molnar --- tools/perf/perf.h | 59 ++++++++++++++++++++++++++++++++++++++---------- tools/perf/tests/rdpmc.c | 2 -- tools/perf/util/evlist.h | 4 ++-- 3 files changed, 49 insertions(+), 16 deletions(-) diff --git a/tools/perf/perf.h b/tools/perf/perf.h index f61c230..6a587e84 100644 --- a/tools/perf/perf.h +++ b/tools/perf/perf.h @@ -4,6 +4,8 @@ #include #if defined(__i386__) +#define mb() asm volatile("lock; addl $0,0(%%esp)" ::: "memory") +#define wmb() asm volatile("lock; addl $0,0(%%esp)" ::: "memory") #define rmb() asm volatile("lock; addl $0,0(%%esp)" ::: "memory") #define cpu_relax() asm volatile("rep; nop" ::: "memory"); #define CPUINFO_PROC "model name" @@ -13,6 +15,8 @@ #endif #if defined(__x86_64__) +#define mb() asm volatile("mfence" ::: "memory") +#define wmb() asm volatile("sfence" ::: "memory") #define rmb() asm volatile("lfence" ::: "memory") #define cpu_relax() asm volatile("rep; nop" ::: "memory"); #define CPUINFO_PROC "model name" @@ -23,45 +27,61 @@ #ifdef __powerpc__ #include "../../arch/powerpc/include/uapi/asm/unistd.h" +#define mb() asm volatile ("sync" ::: "memory") +#define wmb() asm volatile ("sync" ::: "memory") #define rmb() asm volatile ("sync" ::: "memory") -#define cpu_relax() asm volatile ("" ::: "memory"); #define CPUINFO_PROC "cpu" #endif #ifdef __s390__ +#define mb() asm volatile("bcr 15,0" ::: "memory") +#define wmb() asm volatile("bcr 15,0" ::: "memory") #define rmb() asm volatile("bcr 15,0" ::: "memory") -#define cpu_relax() asm volatile("" ::: "memory"); #endif #ifdef __sh__ #if defined(__SH4A__) || defined(__SH5__) +# define mb() asm volatile("synco" ::: "memory") +# define wmb() asm volatile("synco" ::: "memory") # define rmb() asm volatile("synco" ::: "memory") #else +# define mb() asm volatile("" ::: "memory") +# define wmb() asm volatile("" ::: "memory") # define rmb() asm volatile("" ::: "memory") #endif -#define cpu_relax() asm volatile("" ::: "memory") #define CPUINFO_PROC "cpu type" #endif #ifdef __hppa__ +#define mb() asm volatile("" ::: "memory") +#define wmb() asm volatile("" ::: "memory") #define rmb() asm volatile("" ::: "memory") -#define cpu_relax() asm volatile("" ::: "memory"); #define CPUINFO_PROC "cpu" #endif #ifdef __sparc__ +#ifdef __LP64__ +#define mb() asm volatile("ba,pt %%xcc, 1f\n" \ + "membar #StoreLoad\n" \ + "1:\n":::"memory") +#else +#define mb() asm volatile("":::"memory") +#endif +#define wmb() asm volatile("":::"memory") #define rmb() asm volatile("":::"memory") -#define cpu_relax() asm volatile("":::"memory") #define CPUINFO_PROC "cpu" #endif #ifdef __alpha__ +#define mb() asm volatile("mb" ::: "memory") +#define wmb() asm volatile("wmb" ::: "memory") #define rmb() asm volatile("mb" ::: "memory") -#define cpu_relax() asm volatile("" ::: "memory") #define CPUINFO_PROC "cpu model" #endif #ifdef __ia64__ +#define mb() asm volatile ("mf" ::: "memory") +#define wmb() asm volatile ("mf" ::: "memory") #define rmb() asm volatile ("mf" ::: "memory") #define cpu_relax() asm volatile ("hint @pause" ::: "memory") #define CPUINFO_PROC "model name" @@ -72,40 +92,55 @@ * Use the __kuser_memory_barrier helper in the CPU helper page. See * arch/arm/kernel/entry-armv.S in the kernel source for details. */ +#define mb() ((void(*)(void))0xffff0fa0)() +#define wmb() ((void(*)(void))0xffff0fa0)() #define rmb() ((void(*)(void))0xffff0fa0)() -#define cpu_relax() asm volatile("":::"memory") #define CPUINFO_PROC "Processor" #endif #ifdef __aarch64__ -#define rmb() asm volatile("dmb ld" ::: "memory") +#define mb() asm volatile("dmb ish" ::: "memory") +#define wmb() asm volatile("dmb ishld" ::: "memory") +#define rmb() asm volatile("dmb ishst" ::: "memory") #define cpu_relax() asm volatile("yield" ::: "memory") #endif #ifdef __mips__ -#define rmb() asm volatile( \ +#define mb() asm volatile( \ ".set mips2\n\t" \ "sync\n\t" \ ".set mips0" \ : /* no output */ \ : /* no input */ \ : "memory") -#define cpu_relax() asm volatile("" ::: "memory") +#define wmb() mb() +#define rmb() mb() #define CPUINFO_PROC "cpu model" #endif #ifdef __arc__ +#define mb() asm volatile("" ::: "memory") +#define wmb() asm volatile("" ::: "memory") #define rmb() asm volatile("" ::: "memory") -#define cpu_relax() rmb() #define CPUINFO_PROC "Processor" #endif #ifdef __metag__ +#define mb() asm volatile("" ::: "memory") +#define wmb() asm volatile("" ::: "memory") #define rmb() asm volatile("" ::: "memory") -#define cpu_relax() asm volatile("" ::: "memory") #define CPUINFO_PROC "CPU" #endif +#define barrier() asm volatile ("" ::: "memory") + +#ifndef cpu_relax +#define cpu_relax() barrier() +#endif + +#define ACCESS_ONCE(x) (*(volatile typeof(x) *)&(x)) + + #include #include #include diff --git a/tools/perf/tests/rdpmc.c b/tools/perf/tests/rdpmc.c index ff94886..46649c2 100644 --- a/tools/perf/tests/rdpmc.c +++ b/tools/perf/tests/rdpmc.c @@ -9,8 +9,6 @@ #if defined(__x86_64__) || defined(__i386__) -#define barrier() asm volatile("" ::: "memory") - static u64 rdpmc(unsigned int counter) { unsigned int low, high; diff --git a/tools/perf/util/evlist.h b/tools/perf/util/evlist.h index e99eaed..ecaa582 100644 --- a/tools/perf/util/evlist.h +++ b/tools/perf/util/evlist.h @@ -177,7 +177,7 @@ int perf_evlist__strerror_open(struct perf_evlist *evlist, int err, char *buf, s static inline unsigned int perf_mmap__read_head(struct perf_mmap *mm) { struct perf_event_mmap_page *pc = mm->base; - int head = pc->data_head; + int head = ACCESS_ONCE(pc->data_head); rmb(); return head; } @@ -190,7 +190,7 @@ static inline void perf_mmap__write_tail(struct perf_mmap *md, /* * ensure all reads are done before we write the tail out. */ - /* mb(); */ + mb(); pc->data_tail = tail; } -- 2.7.4