From mboxrd@z Thu Jan 1 00:00:00 1970 Received: by rv-out-0910.google.com with SMTP id f1so707191rvb.26 for ; Sun, 30 Mar 2008 16:22:28 -0700 (PDT) Message-ID: <86802c440803301622j2874ca56t51b52a54920a233b@mail.gmail.com> Date: Sun, 30 Mar 2008 16:22:28 -0700 From: "Yinghai Lu" Subject: Re: [PATCH 8/8] x86_64: Support for new UV apic In-Reply-To: <20080328191216.GA16455@sgi.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <20080328191216.GA16455@sgi.com> Sender: owner-linux-mm@kvack.org Return-Path: To: Jack Steiner , Andi Kleen Cc: mingo@elte.hu, tglx@linutronix.de, linux-mm@kvack.org, linux-kernel@vger.kernel.org List-ID: On Fri, Mar 28, 2008 at 12:12 PM, Jack Steiner wrote: > > UV supports really big systems. So big, in fact, that the APICID register > does not contain enough bits to contain an APICID that is unique across all > cpus. > > The UV BIOS supports 3 APICID modes: > > - legacy mode. This mode uses the old APIC mode where > APICID is in bits [31:24] of the APICID register. > > - x2apic mode. This mode is whitebox-compatible. APICIDs > are unique across all cpus. Standard x2apic APIC operations > (Intel-defined) can be used for IPIs. The node identifier > fits within the Intel-defined portion of the APICID register. > > - x2apic-uv mode. In this mode, the APICIDs on each node have > unique IDs, but IDs on different node are not unique. For example, > if each mode has 32 cpus, the APICIDs on each node might be > 0 - 31. Every node has the same set of IDs. > The UV hub is used to route IPIs/interrupts to the correct node. > Traditional APIC operations WILL NOT WORK. > > In x2apic-uv mode, the ACPI tables all contain a full unique ID (note: > exact bit layout still changing but the following is close): > > nnnnnnnnnnlc0cch > n = unique node number > l = socket number on board > c = core > h = hyperthread > > Only the "lc0cch" bits are written to the APICID register. The remaining bits are > supplied by having the get_apic_id() function "OR" the extra bits into the value > read from the APICID register. (Hmmm.. why not keep the ENTIRE APICID register > in per-cpu data....) > > The x2apic-uv mode is recognized by the MADT table containing: > oem_id = "SGI" > oem_table_id = "UV-X" > > Based on: > git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-x86.git > > Signed-off-by: Jack Steiner > > --- > arch/x86/kernel/Makefile | 2 > arch/x86/kernel/apic_64.c | 2 > arch/x86/kernel/genapic_64.c | 18 ++ > arch/x86/kernel/genx2apic_uv_x.c | 245 +++++++++++++++++++++++++++++++++++++++ > arch/x86/kernel/setup64.c | 4 > arch/x86/kernel/smpboot.c | 5 > include/asm-x86/genapic_64.h | 5 > include/asm-x86/smp.h | 5 > 8 files changed, 285 insertions(+), 1 deletion(-) > > Index: linux/arch/x86/kernel/genapic_64.c > =================================================================== > --- linux.orig/arch/x86/kernel/genapic_64.c 2008-03-28 13:06:07.000000000 -0500 > +++ linux/arch/x86/kernel/genapic_64.c 2008-03-28 13:06:12.000000000 -0500 > @@ -15,6 +15,7 @@ > #include > #include > #include > +#include > > #include > #include > @@ -32,6 +33,7 @@ void *x86_cpu_to_apicid_early_ptr; > #endif > DEFINE_PER_CPU(u16, x86_cpu_to_apicid) = BAD_APICID; > EXPORT_PER_CPU_SYMBOL(x86_cpu_to_apicid); > +DEFINE_PER_CPU(int, x2apic_extra_bits); > > struct genapic __read_mostly *genapic = &apic_flat; > > @@ -42,6 +44,9 @@ static enum uv_system_type uv_system_typ > */ > void __init setup_apic_routing(void) > { > + if (uv_system_type == UV_NON_UNIQUE_APIC) > + genapic = &apic_x2apic_uv_x; > + else > #ifdef CONFIG_ACPI > /* > * Quirk: some x86_64 machines can only use physical APIC mode > @@ -82,6 +87,19 @@ int __init acpi_madt_oem_check(char *oem > return 0; > } > > +unsigned int read_apic_id(void) > +{ > + unsigned int id; > + > + WARN_ON(preemptible()); > + id = apic_read(APIC_ID); > + if (uv_system_type >= UV_X2APIC) > + id |= __get_cpu_var(x2apic_extra_bits); > + else > + id = (id >> 24) & 0xFFu;; > + return id; > +} so this is "the new one of Friday"? it still wrong. you can not shit id here. ot broke all x86_64 smp. Did you test it on non UV_X2APIC box? YH -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org