diff options
| -rw-r--r-- | arch/powerpc/include/asm/lppaca.h | 2 | ||||
| -rw-r--r-- | arch/powerpc/platforms/pseries/dtl.c | 11 | ||||
| -rw-r--r-- | arch/powerpc/platforms/pseries/lpar.c | 4 |
3 files changed, 16 insertions, 1 deletions
diff --git a/arch/powerpc/include/asm/lppaca.h b/arch/powerpc/include/asm/lppaca.h index a8ac2b8988d4..e45b7293414d 100644 --- a/arch/powerpc/include/asm/lppaca.h +++ b/arch/powerpc/include/asm/lppaca.h @@ -32,6 +32,7 @@ */ #include <linux/cache.h> #include <linux/threads.h> +#include <linux/spinlock_types.h> #include <asm/types.h> #include <asm/mmu.h> #include <asm/firmware.h> @@ -166,6 +167,7 @@ struct dtl_entry { #define DTL_LOG_ALL (DTL_LOG_CEDE | DTL_LOG_PREEMPT | DTL_LOG_FAULT) extern struct kmem_cache *dtl_cache; +extern rwlock_t dtl_access_lock; /* * When CONFIG_VIRT_CPU_ACCOUNTING_NATIVE = y, the cpu accounting code controls diff --git a/arch/powerpc/platforms/pseries/dtl.c b/arch/powerpc/platforms/pseries/dtl.c index fb05804adb2f..ae4fb2a68758 100644 --- a/arch/powerpc/platforms/pseries/dtl.c +++ b/arch/powerpc/platforms/pseries/dtl.c @@ -193,11 +193,16 @@ static int dtl_enable(struct dtl *dtl) if (dtl->buf) return -EBUSY; + /* ensure there are no other conflicting dtl users */ + if (!read_trylock(&dtl_access_lock)) + return -EBUSY; + n_entries = dtl_buf_entries; buf = kmem_cache_alloc_node(dtl_cache, GFP_KERNEL, cpu_to_node(dtl->cpu)); if (!buf) { printk(KERN_WARNING "%s: buffer alloc failed for cpu %d\n", __func__, dtl->cpu); + read_unlock(&dtl_access_lock); return -ENOMEM; } @@ -214,8 +219,11 @@ static int dtl_enable(struct dtl *dtl) } spin_unlock(&dtl->lock); - if (rc) + if (rc) { + read_unlock(&dtl_access_lock); kmem_cache_free(dtl_cache, buf); + } + return rc; } @@ -227,6 +235,7 @@ static void dtl_disable(struct dtl *dtl) dtl->buf = NULL; dtl->buf_entries = 0; spin_unlock(&dtl->lock); + read_unlock(&dtl_access_lock); } /* file interface */ diff --git a/arch/powerpc/platforms/pseries/lpar.c b/arch/powerpc/platforms/pseries/lpar.c index da7e7c243864..7869121ab431 100644 --- a/arch/powerpc/platforms/pseries/lpar.c +++ b/arch/powerpc/platforms/pseries/lpar.c @@ -113,6 +113,10 @@ void register_dtl_buffer(int cpu) } } +#ifdef CONFIG_PPC_SPLPAR +DEFINE_RWLOCK(dtl_access_lock); +#endif /* CONFIG_PPC_SPLPAR */ + void vpa_init(int cpu) { int hwcpu = get_hard_smp_processor_id(cpu); |