Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755994Ab3CUPx4 (ORCPT ); Thu, 21 Mar 2013 11:53:56 -0400 Received: from mail-da0-f54.google.com ([209.85.210.54]:59816 "EHLO mail-da0-f54.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755938Ab3CUPxy (ORCPT ); Thu, 21 Mar 2013 11:53:54 -0400 Message-ID: <514B2D0E.808@gmail.com> Date: Thu, 21 Mar 2013 08:53:50 -0700 From: David Daney User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130110 Thunderbird/17.0.2 MIME-Version: 1.0 To: Huacai Chen , Ralf Baechle CC: linux-mips@linux-mips.org, linux-kernel@vger.kernel.org, Fuxin Zhang , Zhangjin Wu , Hongbing Hu Subject: Re: [PATCH V2 01/02] MIPS: Build uasm-generated code only once to avoid CPU Hotplug problem References: <1363524578-3765-1-git-send-email-chenhc@lemote.com> <514A42F2.4080501@gmail.com> In-Reply-To: <514A42F2.4080501@gmail.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4349 Lines: 127 On 03/20/2013 04:14 PM, David Daney wrote: > On 03/17/2013 05:49 AM, Huacai Chen wrote: >> This and the next patch resolve memory corruption problems while CPU >> hotplug. Without these patches, memory corruption can triggered easily >> as below: >> [...] > > We were seeing the same crashes, this patch set seems to fix the problem. > > Acked-by: David Daney On second thought... > >> --- >> arch/mips/include/asm/cpu-features.h | 3 +++ >> .../asm/mach-loongson/cpu-feature-overrides.h | 1 + >> arch/mips/mm/page.c | 10 ++++++++++ >> arch/mips/mm/tlbex.c | 10 ++++++++-- >> 4 files changed, 22 insertions(+), 2 deletions(-) >> >> diff --git a/arch/mips/include/asm/cpu-features.h >> b/arch/mips/include/asm/cpu-features.h >> index 1a57e8b..e5ec8fc 100644 >> --- a/arch/mips/include/asm/cpu-features.h >> +++ b/arch/mips/include/asm/cpu-features.h >> @@ -113,6 +113,9 @@ >> #ifndef cpu_has_pindexed_dcache >> #define cpu_has_pindexed_dcache (cpu_data[0].dcache.flags & >> MIPS_CACHE_PINDEX) >> #endif >> +#ifndef cpu_has_local_ebase >> +#define cpu_has_local_ebase 1 This really should default to 0 and only be set for (??who knows what??). David Daney >> +#endif >> >> /* >> * I-Cache snoops remote store. This only matters on SMP. Some >> multiprocessors >> diff --git >> a/arch/mips/include/asm/mach-loongson/cpu-feature-overrides.h >> b/arch/mips/include/asm/mach-loongson/cpu-feature-overrides.h >> index 75fd8c0..c0f3ef4 100644 >> --- a/arch/mips/include/asm/mach-loongson/cpu-feature-overrides.h >> +++ b/arch/mips/include/asm/mach-loongson/cpu-feature-overrides.h >> @@ -57,5 +57,6 @@ >> #define cpu_has_vint 0 >> #define cpu_has_vtag_icache 0 >> #define cpu_has_watch 1 >> +#define cpu_has_local_ebase 0 >> >> #endif /* __ASM_MACH_LOONGSON_CPU_FEATURE_OVERRIDES_H */ >> diff --git a/arch/mips/mm/page.c b/arch/mips/mm/page.c >> index a29fba5..4eb8dcf 100644 >> --- a/arch/mips/mm/page.c >> +++ b/arch/mips/mm/page.c >> @@ -247,6 +247,11 @@ void __cpuinit build_clear_page(void) >> struct uasm_label *l = labels; >> struct uasm_reloc *r = relocs; >> int i; >> + static atomic_t run_once = ATOMIC_INIT(0); >> + >> + if (atomic_xchg(&run_once, 1)) { >> + return; >> + } >> >> memset(labels, 0, sizeof(labels)); >> memset(relocs, 0, sizeof(relocs)); >> @@ -389,6 +394,11 @@ void __cpuinit build_copy_page(void) >> struct uasm_label *l = labels; >> struct uasm_reloc *r = relocs; >> int i; >> + static atomic_t run_once = ATOMIC_INIT(0); >> + >> + if (atomic_xchg(&run_once, 1)) { >> + return; >> + } >> >> memset(labels, 0, sizeof(labels)); >> memset(relocs, 0, sizeof(relocs)); >> diff --git a/arch/mips/mm/tlbex.c b/arch/mips/mm/tlbex.c >> index 820e661..6bc28b4 100644 >> --- a/arch/mips/mm/tlbex.c >> +++ b/arch/mips/mm/tlbex.c >> @@ -2162,8 +2162,11 @@ void __cpuinit build_tlb_refill_handler(void) >> case CPU_TX3922: >> case CPU_TX3927: >> #ifndef CONFIG_MIPS_PGD_C0_CONTEXT >> - build_r3000_tlb_refill_handler(); >> + if (cpu_has_local_ebase) >> + build_r3000_tlb_refill_handler(); >> if (!run_once) { >> + if (!cpu_has_local_ebase) >> + build_r3000_tlb_refill_handler(); >> build_r3000_tlb_load_handler(); >> build_r3000_tlb_store_handler(); >> build_r3000_tlb_modify_handler(); >> @@ -2192,9 +2195,12 @@ void __cpuinit build_tlb_refill_handler(void) >> build_r4000_tlb_load_handler(); >> build_r4000_tlb_store_handler(); >> build_r4000_tlb_modify_handler(); >> + if (!cpu_has_local_ebase) >> + build_r4000_tlb_refill_handler(); >> run_once++; >> } >> - build_r4000_tlb_refill_handler(); >> + if (cpu_has_local_ebase) >> + build_r4000_tlb_refill_handler(); >> } >> } >> >> > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/