From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-x242.google.com (mail-pa0-x242.google.com [IPv6:2607:f8b0:400e:c03::242]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3r4PCL2kNpzDqZV for ; Wed, 11 May 2016 15:03:26 +1000 (AEST) Received: by mail-pa0-x242.google.com with SMTP id gh9so2733081pac.0 for ; Tue, 10 May 2016 22:03:26 -0700 (PDT) Subject: Re: [PATCH] powerpc/tm: Clean up duplication of code To: linuxppc-dev@lists.ozlabs.org, Rashmica Gupta References: <1462942500-30188-1-git-send-email-rashmicy@gmail.com> From: Balbir Singh Message-ID: Date: Wed, 11 May 2016 15:03:19 +1000 MIME-Version: 1.0 In-Reply-To: <1462942500-30188-1-git-send-email-rashmicy@gmail.com> Content-Type: text/plain; charset=utf-8 List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On 11/05/16 14:55, Rashmica Gupta wrote: > The same logic for tm_abort appears twice, so pull it out into a > function. > > Signed-off-by: Rashmica Gupta > --- > arch/powerpc/mm/hash_utils_64.c | 47 ++++++++++++++++++----------------------- > 1 file changed, 21 insertions(+), 26 deletions(-) > > diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c > index 7635b1c6b5da..1cef8f5aee9b 100644 > --- a/arch/powerpc/mm/hash_utils_64.c > +++ b/arch/powerpc/mm/hash_utils_64.c > @@ -1318,6 +1318,25 @@ out_exit: > local_irq_restore(flags); > } > > +#ifdef CONFIG_PPC_TRANSACTIONAL_MEM > + /* Transactions are not aborted by tlbiel, only tlbie. > + * Without, syncing a page back to a block device w/ PIO could pick up > + * transactional data (bad!) so we force an abort here. Before the > + * sync the page will be made read-only, which will flush_hash_page. > + * BIG ISSUE here: if the kernel uses a page from userspace without > + * unmapping it first, it may see the speculated version. > + */ > +static inline void abort_tm(int local) > +{ > + if (local && cpu_has_feature(CPU_FTR_TM) && > + current->thread.regs && > + MSR_TM_ACTIVE(current->thread.regs->msr)) { > + tm_enable(); > + tm_abort(TM_CAUSE_TLBI); > + } > +} While your at this do #else static inline void abort_tm(int local) { } > +#endif > + > /* WARNING: This is called from hash_low_64.S, if you change this prototype, > * do not forget to update the assembly call site ! > */ > @@ -1344,19 +1363,7 @@ void flush_hash_page(unsigned long vpn, real_pte_t pte, int psize, int ssize, > } pte_iterate_hashed_end(); > > #ifdef CONFIG_PPC_TRANSACTIONAL_MEM Then remove these extra #ifdef > - /* Transactions are not aborted by tlbiel, only tlbie. > - * Without, syncing a page back to a block device w/ PIO could pick up > - * transactional data (bad!) so we force an abort here. Before the > - * sync the page will be made read-only, which will flush_hash_page. > - * BIG ISSUE here: if the kernel uses a page from userspace without > - * unmapping it first, it may see the speculated version. > - */ > - if (local && cpu_has_feature(CPU_FTR_TM) && > - current->thread.regs && > - MSR_TM_ACTIVE(current->thread.regs->msr)) { > - tm_enable(); > - tm_abort(TM_CAUSE_TLBI); > - } > + abort_tm(local); > #endif > } > > @@ -1415,19 +1422,7 @@ void flush_hash_hugepage(unsigned long vsid, unsigned long addr, > } > tm_abort: > #ifdef CONFIG_PPC_TRANSACTIONAL_MEM Then remove these extra #ifdef > - /* Transactions are not aborted by tlbiel, only tlbie. > - * Without, syncing a page back to a block device w/ PIO could pick up > - * transactional data (bad!) so we force an abort here. Before the > - * sync the page will be made read-only, which will flush_hash_page. > - * BIG ISSUE here: if the kernel uses a page from userspace without > - * unmapping it first, it may see the speculated version. > - */ > - if (local && cpu_has_feature(CPU_FTR_TM) && > - current->thread.regs && > - MSR_TM_ACTIVE(current->thread.regs->msr)) { > - tm_enable(); > - tm_abort(TM_CAUSE_TLBI); > - } > + abort_tm(local); > #endif > return; > } >