____cacheline_aligned_in_smp macro is needed to avoid cache bouncing in SMP system, which is used in ptr_ring lib. So add the related macro in order to bulid ptr_ring from user space. As SMP_CACHE_BYTES is 64 bytes for arm64 and most of x86 system, so use 64 bytes as the default SMP_CACHE_BYTES if SMP_CACHE_BYTES is not defined. Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com> --- tools/include/linux/cache.h | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) create mode 100644 tools/include/linux/cache.h diff --git a/tools/include/linux/cache.h b/tools/include/linux/cache.h new file mode 100644 index 0000000..df04307 --- /dev/null +++ b/tools/include/linux/cache.h @@ -0,0 +1,25 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __TOOLS_LINUX__CACHE_H +#define __TOOLS_LINUX__CACHE_H + +#ifndef CONFIG_SMP +#define CONFIG_SMP 1 +#endif + +#ifndef SMP_CACHE_BYTES +#define SMP_CACHE_BYTES 64 +#endif + +#ifndef ____cacheline_aligned +#define ____cacheline_aligned __attribute__((__aligned__(SMP_CACHE_BYTES))) +#endif + +#ifndef ____cacheline_aligned_in_smp +#ifdef CONFIG_SMP +#define ____cacheline_aligned_in_smp ____cacheline_aligned +#else +#define ____cacheline_aligned_in_smp +#endif /* CONFIG_SMP */ +#endif + +#endif /* __LINUX_CACHE_H */ -- 2.7.4

As x86 and arm64 is the two available systems that I can build and test the cpu_relax() implementation, so only add cpu_relax() implementation for x86 and arm64, other arches can be added easily when needed. Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com> --- tools/include/asm/processor.h | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) create mode 100644 tools/include/asm/processor.h diff --git a/tools/include/asm/processor.h b/tools/include/asm/processor.h new file mode 100644 index 0000000..f9b3902 --- /dev/null +++ b/tools/include/asm/processor.h @@ -0,0 +1,26 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#ifndef __TOOLS_LINUX_ASM_PROCESSOR_H +#define __TOOLS_LINUX_ASM_PROCESSOR_H + +#if defined(__i386__) || defined(__x86_64__) +/* REP NOP (PAUSE) is a good thing to insert into busy-wait loops. */ +static __always_inline void rep_nop(void) +{ + asm volatile("rep; nop" ::: "memory"); +} + +static __always_inline void cpu_relax(void) +{ + rep_nop(); +} +#elif defined(__aarch64__) +static inline void cpu_relax(void) +{ + asm volatile("yield" ::: "memory"); +} +#else +#error "Architecture not supported" +#endif + +#endif -- 2.7.4

Use the common infrastructure in tools/include to build ptr_ring.h in user space. Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com> --- tools/virtio/ringtest/Makefile | 2 +- tools/virtio/ringtest/main.h | 99 +++----------------------------------- tools/virtio/ringtest/ptr_ring.c | 101 ++------------------------------------- 3 files changed, 10 insertions(+), 192 deletions(-) diff --git a/tools/virtio/ringtest/Makefile b/tools/virtio/ringtest/Makefile index 85c98c2..89fc024 100644 --- a/tools/virtio/ringtest/Makefile +++ b/tools/virtio/ringtest/Makefile @@ -3,7 +3,7 @@ all: all: ring virtio_ring_0_9 virtio_ring_poll virtio_ring_inorder ptr_ring noring -CFLAGS += -Wall +CFLAGS += -Wall -I../../include CFLAGS += -pthread -O2 -ggdb -flto -fwhole-program LDFLAGS += -pthread -O2 -ggdb -flto -fwhole-program diff --git a/tools/virtio/ringtest/main.h b/tools/virtio/ringtest/main.h index 6d1fccd..26a8659 100644 --- a/tools/virtio/ringtest/main.h +++ b/tools/virtio/ringtest/main.h @@ -10,6 +10,12 @@ #include <stdbool.h> +#include <asm/barrier.h> +#include <asm/processor.h> + +#define smp_acquire smp_rmb +#define smp_release smp_wmb + extern int param; extern bool do_exit; @@ -87,18 +93,6 @@ void wait_for_call(void); extern unsigned ring_size; -/* Compiler barrier - similar to what Linux uses */ -#define barrier() asm volatile("" ::: "memory") - -/* Is there a portable way to do this? */ -#if defined(__x86_64__) || defined(__i386__) -#define cpu_relax() asm ("rep; nop" ::: "memory") -#elif defined(__s390x__) -#define cpu_relax() barrier() -#else -#define cpu_relax() assert(0) -#endif - extern bool do_relax; static inline void busy_wait(void) @@ -110,85 +104,4 @@ static inline void busy_wait(void) barrier(); } -#if defined(__x86_64__) || defined(__i386__) -#define smp_mb() asm volatile("lock; addl $0,-132(%%rsp)" ::: "memory", "cc") -#else -/* - * Not using __ATOMIC_SEQ_CST since gcc docs say they are only synchronized - * with other __ATOMIC_SEQ_CST calls. - */ -#define smp_mb() __sync_synchronize() -#endif - -/* - * This abuses the atomic builtins for thread fences, and - * adds a compiler barrier. - */ -#define smp_release() do { \ - barrier(); \ - __atomic_thread_fence(__ATOMIC_RELEASE); \ -} while (0) - -#define smp_acquire() do { \ - __atomic_thread_fence(__ATOMIC_ACQUIRE); \ - barrier(); \ -} while (0) - -#if defined(__i386__) || defined(__x86_64__) || defined(__s390x__) -#define smp_wmb() barrier() -#else -#define smp_wmb() smp_release() -#endif - -#ifdef __alpha__ -#define smp_read_barrier_depends() smp_acquire() -#else -#define smp_read_barrier_depends() do {} while(0) -#endif - -static __always_inline -void __read_once_size(const volatile void *p, void *res, int size) -{ - switch (size) { \ - case 1: *(unsigned char *)res = *(volatile unsigned char *)p; break; \ - case 2: *(unsigned short *)res = *(volatile unsigned short *)p; break; \ - case 4: *(unsigned int *)res = *(volatile unsigned int *)p; break; \ - case 8: *(unsigned long long *)res = *(volatile unsigned long long *)p; break; \ - default: \ - barrier(); \ - __builtin_memcpy((void *)res, (const void *)p, size); \ - barrier(); \ - } \ -} - -static __always_inline void __write_once_size(volatile void *p, void *res, int size) -{ - switch (size) { - case 1: *(volatile unsigned char *)p = *(unsigned char *)res; break; - case 2: *(volatile unsigned short *)p = *(unsigned short *)res; break; - case 4: *(volatile unsigned int *)p = *(unsigned int *)res; break; - case 8: *(volatile unsigned long long *)p = *(unsigned long long *)res; break; - default: - barrier(); - __builtin_memcpy((void *)p, (const void *)res, size); - barrier(); - } -} - -#define READ_ONCE(x) \ -({ \ - union { typeof(x) __val; char __c[1]; } __u; \ - __read_once_size(&(x), __u.__c, sizeof(x)); \ - smp_read_barrier_depends(); /* Enforce dependency ordering from x */ \ - __u.__val; \ -}) - -#define WRITE_ONCE(x, val) \ -({ \ - union { typeof(x) __val; char __c[1]; } __u = \ - { .__val = (typeof(x)) (val) }; \ - __write_once_size(&(x), __u.__c, sizeof(x)); \ - __u.__val; \ -}) - #endif diff --git a/tools/virtio/ringtest/ptr_ring.c b/tools/virtio/ringtest/ptr_ring.c index c9b2633..e9849a3 100644 --- a/tools/virtio/ringtest/ptr_ring.c +++ b/tools/virtio/ringtest/ptr_ring.c @@ -10,104 +10,9 @@ #include <errno.h> #include <limits.h> -#define SMP_CACHE_BYTES 64 -#define cache_line_size() SMP_CACHE_BYTES -#define ____cacheline_aligned_in_smp __attribute__ ((aligned (SMP_CACHE_BYTES))) -#define unlikely(x) (__builtin_expect(!!(x), 0)) -#define likely(x) (__builtin_expect(!!(x), 1)) -#define ALIGN(x, a) (((x) + (a) - 1) / (a) * (a)) -#define SIZE_MAX (~(size_t)0) -#define KMALLOC_MAX_SIZE SIZE_MAX - -typedef pthread_spinlock_t spinlock_t; - -typedef int gfp_t; -#define __GFP_ZERO 0x1 - -static void *kmalloc(unsigned size, gfp_t gfp) -{ - void *p = memalign(64, size); - if (!p) - return p; - - if (gfp & __GFP_ZERO) - memset(p, 0, size); - return p; -} - -static inline void *kzalloc(unsigned size, gfp_t flags) -{ - return kmalloc(size, flags | __GFP_ZERO); -} - -static inline void *kmalloc_array(size_t n, size_t size, gfp_t flags) -{ - if (size != 0 && n > SIZE_MAX / size) - return NULL; - return kmalloc(n * size, flags); -} - -static inline void *kcalloc(size_t n, size_t size, gfp_t flags) -{ - return kmalloc_array(n, size, flags | __GFP_ZERO); -} - -static void kfree(void *p) -{ - if (p) - free(p); -} - -#define kvmalloc_array kmalloc_array -#define kvfree kfree - -static void spin_lock_init(spinlock_t *lock) -{ - int r = pthread_spin_init(lock, 0); - assert(!r); -} - -static void spin_lock(spinlock_t *lock) -{ - int ret = pthread_spin_lock(lock); - assert(!ret); -} - -static void spin_unlock(spinlock_t *lock) -{ - int ret = pthread_spin_unlock(lock); - assert(!ret); -} - -static void spin_lock_bh(spinlock_t *lock) -{ - spin_lock(lock); -} - -static void spin_unlock_bh(spinlock_t *lock) -{ - spin_unlock(lock); -} - -static void spin_lock_irq(spinlock_t *lock) -{ - spin_lock(lock); -} - -static void spin_unlock_irq(spinlock_t *lock) -{ - spin_unlock(lock); -} - -static void spin_lock_irqsave(spinlock_t *lock, unsigned long f) -{ - spin_lock(lock); -} - -static void spin_unlock_irqrestore(spinlock_t *lock, unsigned long f) -{ - spin_unlock(lock); -} +#include <linux/cache.h> +#include <linux/slab.h> +#include <linux/spinlock.h> #include "../../../include/linux/ptr_ring.h" -- 2.7.4