linux_dsm_epyc7002/arch/ia64/kernel/head.S

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License cleanup: add SPDX GPL-2.0 license identifier to files with no license Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 21:07:57 +07:00
/* SPDX-License-Identifier: GPL-2.0 */
/*
* Here is where the ball gets rolling as far as the kernel is concerned.
* When control is transferred to _start, the bootload has already
* loaded us to the correct address. All that's left to do here is
* to set up the kernel's global pointer and jump to the kernel
* entry point.
*
* Copyright (C) 1998-2001, 2003, 2005 Hewlett-Packard Co
* David Mosberger-Tang <davidm@hpl.hp.com>
* Stephane Eranian <eranian@hpl.hp.com>
* Copyright (C) 1999 VA Linux Systems
* Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
* Copyright (C) 1999 Intel Corp.
* Copyright (C) 1999 Asit Mallick <Asit.K.Mallick@intel.com>
* Copyright (C) 1999 Don Dugger <Don.Dugger@intel.com>
* Copyright (C) 2002 Fenghua Yu <fenghua.yu@intel.com>
* -Optimize __ia64_save_fpu() and __ia64_load_fpu() for Itanium 2.
* Copyright (C) 2004 Ashok Raj <ashok.raj@intel.com>
* Support for CPU Hotplug
*/
#include <asm/asmmacro.h>
#include <asm/fpu.h>
#include <asm/kregs.h>
#include <asm/mmu_context.h>
#include <asm/asm-offsets.h>
#include <asm/pal.h>
#include <asm/pgtable.h>
#include <asm/processor.h>
#include <asm/ptrace.h>
#include <asm/mca_asm.h>
#include <linux/init.h>
#include <linux/linkage.h>
#include <asm/export.h>
#ifdef CONFIG_HOTPLUG_CPU
#define SAL_PSR_BITS_TO_SET \
(IA64_PSR_AC | IA64_PSR_BN | IA64_PSR_MFH | IA64_PSR_MFL)
#define SAVE_FROM_REG(src, ptr, dest) \
mov dest=src;; \
st8 [ptr]=dest,0x08
#define RESTORE_REG(reg, ptr, _tmp) \
ld8 _tmp=[ptr],0x08;; \
mov reg=_tmp
#define SAVE_BREAK_REGS(ptr, _idx, _breg, _dest)\
mov ar.lc=IA64_NUM_DBG_REGS-1;; \
mov _idx=0;; \
1: \
SAVE_FROM_REG(_breg[_idx], ptr, _dest);; \
add _idx=1,_idx;; \
br.cloop.sptk.many 1b
#define RESTORE_BREAK_REGS(ptr, _idx, _breg, _tmp, _lbl)\
mov ar.lc=IA64_NUM_DBG_REGS-1;; \
mov _idx=0;; \
_lbl: RESTORE_REG(_breg[_idx], ptr, _tmp);; \
add _idx=1, _idx;; \
br.cloop.sptk.many _lbl
#define SAVE_ONE_RR(num, _reg, _tmp) \
movl _tmp=(num<<61);; \
mov _reg=rr[_tmp]
#define SAVE_REGION_REGS(_tmp, _r0, _r1, _r2, _r3, _r4, _r5, _r6, _r7) \
SAVE_ONE_RR(0,_r0, _tmp);; \
SAVE_ONE_RR(1,_r1, _tmp);; \
SAVE_ONE_RR(2,_r2, _tmp);; \
SAVE_ONE_RR(3,_r3, _tmp);; \
SAVE_ONE_RR(4,_r4, _tmp);; \
SAVE_ONE_RR(5,_r5, _tmp);; \
SAVE_ONE_RR(6,_r6, _tmp);; \
SAVE_ONE_RR(7,_r7, _tmp);;
#define STORE_REGION_REGS(ptr, _r0, _r1, _r2, _r3, _r4, _r5, _r6, _r7) \
st8 [ptr]=_r0, 8;; \
st8 [ptr]=_r1, 8;; \
st8 [ptr]=_r2, 8;; \
st8 [ptr]=_r3, 8;; \
st8 [ptr]=_r4, 8;; \
st8 [ptr]=_r5, 8;; \
st8 [ptr]=_r6, 8;; \
st8 [ptr]=_r7, 8;;
#define RESTORE_REGION_REGS(ptr, _idx1, _idx2, _tmp) \
mov ar.lc=0x08-1;; \
movl _idx1=0x00;; \
RestRR: \
dep.z _idx2=_idx1,61,3;; \
ld8 _tmp=[ptr],8;; \
mov rr[_idx2]=_tmp;; \
srlz.d;; \
add _idx1=1,_idx1;; \
br.cloop.sptk.few RestRR
#define SET_AREA_FOR_BOOTING_CPU(reg1, reg2) \
movl reg1=sal_state_for_booting_cpu;; \
ld8 reg2=[reg1];;
/*
* Adjust region registers saved before starting to save
* break regs and rest of the states that need to be preserved.
*/
#define SAL_TO_OS_BOOT_HANDOFF_STATE_SAVE(_reg1,_reg2,_pred) \
SAVE_FROM_REG(b0,_reg1,_reg2);; \
SAVE_FROM_REG(b1,_reg1,_reg2);; \
SAVE_FROM_REG(b2,_reg1,_reg2);; \
SAVE_FROM_REG(b3,_reg1,_reg2);; \
SAVE_FROM_REG(b4,_reg1,_reg2);; \
SAVE_FROM_REG(b5,_reg1,_reg2);; \
st8 [_reg1]=r1,0x08;; \
st8 [_reg1]=r12,0x08;; \
st8 [_reg1]=r13,0x08;; \
SAVE_FROM_REG(ar.fpsr,_reg1,_reg2);; \
SAVE_FROM_REG(ar.pfs,_reg1,_reg2);; \
SAVE_FROM_REG(ar.rnat,_reg1,_reg2);; \
SAVE_FROM_REG(ar.unat,_reg1,_reg2);; \
SAVE_FROM_REG(ar.bspstore,_reg1,_reg2);; \
SAVE_FROM_REG(cr.dcr,_reg1,_reg2);; \
SAVE_FROM_REG(cr.iva,_reg1,_reg2);; \
SAVE_FROM_REG(cr.pta,_reg1,_reg2);; \
SAVE_FROM_REG(cr.itv,_reg1,_reg2);; \
SAVE_FROM_REG(cr.pmv,_reg1,_reg2);; \
SAVE_FROM_REG(cr.cmcv,_reg1,_reg2);; \
SAVE_FROM_REG(cr.lrr0,_reg1,_reg2);; \
SAVE_FROM_REG(cr.lrr1,_reg1,_reg2);; \
st8 [_reg1]=r4,0x08;; \
st8 [_reg1]=r5,0x08;; \
st8 [_reg1]=r6,0x08;; \
st8 [_reg1]=r7,0x08;; \
st8 [_reg1]=_pred,0x08;; \
SAVE_FROM_REG(ar.lc, _reg1, _reg2);; \
stf.spill.nta [_reg1]=f2,16;; \
stf.spill.nta [_reg1]=f3,16;; \
stf.spill.nta [_reg1]=f4,16;; \
stf.spill.nta [_reg1]=f5,16;; \
stf.spill.nta [_reg1]=f16,16;; \
stf.spill.nta [_reg1]=f17,16;; \
stf.spill.nta [_reg1]=f18,16;; \
stf.spill.nta [_reg1]=f19,16;; \
stf.spill.nta [_reg1]=f20,16;; \
stf.spill.nta [_reg1]=f21,16;; \
stf.spill.nta [_reg1]=f22,16;; \
stf.spill.nta [_reg1]=f23,16;; \
stf.spill.nta [_reg1]=f24,16;; \
stf.spill.nta [_reg1]=f25,16;; \
stf.spill.nta [_reg1]=f26,16;; \
stf.spill.nta [_reg1]=f27,16;; \
stf.spill.nta [_reg1]=f28,16;; \
stf.spill.nta [_reg1]=f29,16;; \
stf.spill.nta [_reg1]=f30,16;; \
stf.spill.nta [_reg1]=f31,16;;
#else
#define SET_AREA_FOR_BOOTING_CPU(a1, a2)
#define SAL_TO_OS_BOOT_HANDOFF_STATE_SAVE(a1,a2, a3)
#define SAVE_REGION_REGS(_tmp, _r0, _r1, _r2, _r3, _r4, _r5, _r6, _r7)
#define STORE_REGION_REGS(ptr, _r0, _r1, _r2, _r3, _r4, _r5, _r6, _r7)
#endif
#define SET_ONE_RR(num, pgsize, _tmp1, _tmp2, vhpt) \
movl _tmp1=(num << 61);; \
mov _tmp2=((ia64_rid(IA64_REGION_ID_KERNEL, (num<<61)) << 8) | (pgsize << 2) | vhpt);; \
mov rr[_tmp1]=_tmp2
__PAGE_ALIGNED_DATA
.global empty_zero_page
EXPORT_DATA_SYMBOL_GPL(empty_zero_page)
empty_zero_page:
.skip PAGE_SIZE
.global swapper_pg_dir
swapper_pg_dir:
.skip PAGE_SIZE
.rodata
halt_msg:
stringz "Halting kernel\n"
__REF
.global start_ap
/*
* Start the kernel. When the bootloader passes control to _start(), r28
* points to the address of the boot parameter area. Execution reaches
* here in physical mode.
*/
GLOBAL_ENTRY(_start)
start_ap:
.prologue
.save rp, r0 // terminate unwind chain with a NULL rp
.body
rsm psr.i | psr.ic
;;
srlz.i
;;
{
flushrs // must be first insn in group
srlz.i
}
;;
/*
* Save the region registers, predicate before they get clobbered
*/
SAVE_REGION_REGS(r2, r8,r9,r10,r11,r12,r13,r14,r15);
mov r25=pr;;
/*
* Initialize kernel region registers:
* rr[0]: VHPT enabled, page size = PAGE_SHIFT
* rr[1]: VHPT enabled, page size = PAGE_SHIFT
* rr[2]: VHPT enabled, page size = PAGE_SHIFT
* rr[3]: VHPT enabled, page size = PAGE_SHIFT
* rr[4]: VHPT enabled, page size = PAGE_SHIFT
* rr[5]: VHPT enabled, page size = PAGE_SHIFT
* rr[6]: VHPT disabled, page size = IA64_GRANULE_SHIFT
* rr[7]: VHPT disabled, page size = IA64_GRANULE_SHIFT
* We initialize all of them to prevent inadvertently assuming
* something about the state of address translation early in boot.
*/
SET_ONE_RR(0, PAGE_SHIFT, r2, r16, 1);;
SET_ONE_RR(1, PAGE_SHIFT, r2, r16, 1);;
SET_ONE_RR(2, PAGE_SHIFT, r2, r16, 1);;
SET_ONE_RR(3, PAGE_SHIFT, r2, r16, 1);;
SET_ONE_RR(4, PAGE_SHIFT, r2, r16, 1);;
SET_ONE_RR(5, PAGE_SHIFT, r2, r16, 1);;
SET_ONE_RR(6, IA64_GRANULE_SHIFT, r2, r16, 0);;
SET_ONE_RR(7, IA64_GRANULE_SHIFT, r2, r16, 0);;
/*
* Now pin mappings into the TLB for kernel text and data
*/
mov r18=KERNEL_TR_PAGE_SHIFT<<2
movl r17=KERNEL_START
;;
mov cr.itir=r18
mov cr.ifa=r17
mov r16=IA64_TR_KERNEL
mov r3=ip
movl r18=PAGE_KERNEL
;;
dep r2=0,r3,0,KERNEL_TR_PAGE_SHIFT
;;
or r18=r2,r18
;;
srlz.i
;;
itr.i itr[r16]=r18
;;
itr.d dtr[r16]=r18
;;
srlz.i
/*
* Switch into virtual mode:
*/
movl r16=(IA64_PSR_IT|IA64_PSR_IC|IA64_PSR_DT|IA64_PSR_RT|IA64_PSR_DFH|IA64_PSR_BN \
[IA64] Change default PSR.ac from '1' to '0' (Fix erratum #237) April 2014 Itanium processor specification update: http://www.intel.com/content/www/us/en/processors/itanium/itanium-specification-update.html describes this erratum: ========================================================================= 237. Under a complex set of conditions, store to load forwarding for a sub 8-byte load may complete incorrectly Problem: A load instruction may complete incorrectly when a code sequence using 4-byte or smaller load and store operations to the same address is executed in combination with specific timing of all the following concurrent conditions: store to load forwarding, alignment checking enabled, a mis-predicted branch, and complex cache utilization activity. Implication: The affected sub 8-byte instruction may complete incorrectly resulting in unpredictable system behavior. There is an extremely low probability of exposure due to the significant number of complex microarchitectural concurrent conditions required to encounter the erratum. Workaround: Set PSR.ac = 0 to completely avoid the erratum. Disabling Hyper-Threading will significantly reduce exposure to the conditions that contribute to encountering the erratum. Status: See the Summary Table of Changes for the affected steppings. ========================================================================= [Table of changes essentially lists all models from McKinley to Tukwila] The PSR.ac bit controls whether the processor will always generate an unaligned reference trap (0x5a00) for a misaligned data access (when PSR.ac=1) or if it will let the access succeed when running on a cpu that implements logic to handle some unaligned accesses. Way back in 2008 in commit b704882e70d87d7f56db5ff17e2253f3fa90e4f3 [IA64] Rationalize kernel mode alignment checking we made the decision to always enable strict checking. We were already doing so in trap/interrupt context because the common preamble code set this bit - but the rest of supervisor code (and by inheritance user code) ran with PSR.ac=0. We now reverse that decision and set PSR.ac=0 everywhere in the kernel (also inherited by user processes). This will avoid the erratum using the method described in the Itanium specification update. Net effect for users is that the processor will handle unaligned access when it can (typically with a tiny performance bubble in the pipeline ... but much less invasive than taking a trap and having the OS perform the access). Signed-off-by: Tony Luck <tony.luck@intel.com>
2014-03-29 04:42:07 +07:00
|IA64_PSR_DI)
;;
mov cr.ipsr=r16
movl r17=1f
;;
mov cr.iip=r17
mov cr.ifs=r0
;;
rfi
;;
1: // now we are in virtual mode
SET_AREA_FOR_BOOTING_CPU(r2, r16);
STORE_REGION_REGS(r16, r8,r9,r10,r11,r12,r13,r14,r15);
SAL_TO_OS_BOOT_HANDOFF_STATE_SAVE(r16,r17,r25)
;;
// set IVT entry point---can't access I/O ports without it
movl r3=ia64_ivt
;;
mov cr.iva=r3
movl r2=FPSR_DEFAULT
;;
srlz.i
movl gp=__gp
mov ar.fpsr=r2
;;
#define isAP p2 // are we an Application Processor?
#define isBP p3 // are we the Bootstrap Processor?
#ifdef CONFIG_SMP
/*
* Find the init_task for the currently booting CPU. At poweron, and in
* UP mode, task_for_booting_cpu is NULL.
*/
movl r3=task_for_booting_cpu
;;
ld8 r3=[r3]
movl r2=init_task
;;
cmp.eq isBP,isAP=r3,r0
;;
(isAP) mov r2=r3
#else
movl r2=init_task
cmp.eq isBP,isAP=r0,r0
#endif
;;
tpa r3=r2 // r3 == phys addr of task struct
mov r16=-1
(isBP) br.cond.dpnt .load_current // BP stack is on region 5 --- no need to map it
// load mapping for stack (virtaddr in r2, physaddr in r3)
rsm psr.ic
movl r17=PAGE_KERNEL
;;
srlz.d
dep r18=0,r3,0,12
;;
or r18=r17,r18
dep r2=-1,r3,61,3 // IMVA of task
;;
mov r17=rr[r2]
shr.u r16=r3,IA64_GRANULE_SHIFT
;;
dep r17=0,r17,8,24
;;
mov cr.itir=r17
mov cr.ifa=r2
mov r19=IA64_TR_CURRENT_STACK
;;
itr.d dtr[r19]=r18
;;
ssm psr.ic
srlz.d
;;
.load_current:
// load the "current" pointer (r13) and ar.k6 with the current task
mov IA64_KR(CURRENT)=r2 // virtual address
mov IA64_KR(CURRENT_STACK)=r16
mov r13=r2
/*
* Reserve space at the top of the stack for "struct pt_regs". Kernel
* threads don't store interesting values in that structure, but the space
* still needs to be there because time-critical stuff such as the context
* switching can be implemented more efficiently (for example, __switch_to()
* always sets the psr.dfh bit of the task it is switching to).
*/
addl r12=IA64_STK_OFFSET-IA64_PT_REGS_SIZE-16,r2
addl r2=IA64_RBS_OFFSET,r2 // initialize the RSE
mov ar.rsc=0 // place RSE in enforced lazy mode
;;
loadrs // clear the dirty partition
movl r19=__phys_per_cpu_start
mov r18=PERCPU_PAGE_SIZE
;;
#ifndef CONFIG_SMP
add r19=r19,r18
;;
#else
(isAP) br.few 2f
movl r20=__cpu0_per_cpu
;;
shr.u r18=r18,3
1:
ld8 r21=[r19],8;;
st8[r20]=r21,8
adds r18=-1,r18;;
cmp4.lt p7,p6=0,r18
(p7) br.cond.dptk.few 1b
mov r19=r20
;;
2:
#endif
tpa r19=r19
;;
.pred.rel.mutex isBP,isAP
(isBP) mov IA64_KR(PER_CPU_DATA)=r19 // per-CPU base for cpu0
(isAP) mov IA64_KR(PER_CPU_DATA)=r0 // clear physical per-CPU base
;;
mov ar.bspstore=r2 // establish the new RSE stack
;;
mov ar.rsc=0x3 // place RSE in eager mode
(isBP) dep r28=-1,r28,61,3 // make address virtual
(isBP) movl r2=ia64_boot_param
;;
(isBP) st8 [r2]=r28 // save the address of the boot param area passed by the bootloader
#ifdef CONFIG_SMP
(isAP) br.call.sptk.many rp=start_secondary
.ret0:
(isAP) br.cond.sptk self
#endif
// This is executed by the bootstrap processor (bsp) only:
#ifdef CONFIG_IA64_FW_EMU
// initialize PAL & SAL emulator:
br.call.sptk.many rp=sys_fw_init
.ret1:
#endif
br.call.sptk.many rp=start_kernel
.ret2: addl r3=@ltoff(halt_msg),gp
;;
alloc r2=ar.pfs,8,0,2,0
;;
ld8 out0=[r3]
br.call.sptk.many b0=console_print
self: hint @pause
br.sptk.many self // endless loop
END(_start)
.text
GLOBAL_ENTRY(ia64_save_debug_regs)
alloc r16=ar.pfs,1,0,0,0
mov r20=ar.lc // preserve ar.lc
mov ar.lc=IA64_NUM_DBG_REGS-1
mov r18=0
add r19=IA64_NUM_DBG_REGS*8,in0
;;
1: mov r16=dbr[r18]
#ifdef CONFIG_ITANIUM
;;
srlz.d
#endif
mov r17=ibr[r18]
add r18=1,r18
;;
st8.nta [in0]=r16,8
st8.nta [r19]=r17,8
br.cloop.sptk.many 1b
;;
mov ar.lc=r20 // restore ar.lc
br.ret.sptk.many rp
END(ia64_save_debug_regs)
GLOBAL_ENTRY(ia64_load_debug_regs)
alloc r16=ar.pfs,1,0,0,0
lfetch.nta [in0]
mov r20=ar.lc // preserve ar.lc
add r19=IA64_NUM_DBG_REGS*8,in0
mov ar.lc=IA64_NUM_DBG_REGS-1
mov r18=-1
;;
1: ld8.nta r16=[in0],8
ld8.nta r17=[r19],8
add r18=1,r18
;;
mov dbr[r18]=r16
#ifdef CONFIG_ITANIUM
;;
srlz.d // Errata 132 (NoFix status)
#endif
mov ibr[r18]=r17
br.cloop.sptk.many 1b
;;
mov ar.lc=r20 // restore ar.lc
br.ret.sptk.many rp
END(ia64_load_debug_regs)
GLOBAL_ENTRY(__ia64_save_fpu)
alloc r2=ar.pfs,1,4,0,0
adds loc0=96*16-16,in0
adds loc1=96*16-16-128,in0
;;
stf.spill.nta [loc0]=f127,-256
stf.spill.nta [loc1]=f119,-256
;;
stf.spill.nta [loc0]=f111,-256
stf.spill.nta [loc1]=f103,-256
;;
stf.spill.nta [loc0]=f95,-256
stf.spill.nta [loc1]=f87,-256
;;
stf.spill.nta [loc0]=f79,-256
stf.spill.nta [loc1]=f71,-256
;;
stf.spill.nta [loc0]=f63,-256
stf.spill.nta [loc1]=f55,-256
adds loc2=96*16-32,in0
;;
stf.spill.nta [loc0]=f47,-256
stf.spill.nta [loc1]=f39,-256
adds loc3=96*16-32-128,in0
;;
stf.spill.nta [loc2]=f126,-256
stf.spill.nta [loc3]=f118,-256
;;
stf.spill.nta [loc2]=f110,-256
stf.spill.nta [loc3]=f102,-256
;;
stf.spill.nta [loc2]=f94,-256
stf.spill.nta [loc3]=f86,-256
;;
stf.spill.nta [loc2]=f78,-256
stf.spill.nta [loc3]=f70,-256
;;
stf.spill.nta [loc2]=f62,-256
stf.spill.nta [loc3]=f54,-256
adds loc0=96*16-48,in0
;;
stf.spill.nta [loc2]=f46,-256
stf.spill.nta [loc3]=f38,-256
adds loc1=96*16-48-128,in0
;;
stf.spill.nta [loc0]=f125,-256
stf.spill.nta [loc1]=f117,-256
;;
stf.spill.nta [loc0]=f109,-256
stf.spill.nta [loc1]=f101,-256
;;
stf.spill.nta [loc0]=f93,-256
stf.spill.nta [loc1]=f85,-256
;;
stf.spill.nta [loc0]=f77,-256
stf.spill.nta [loc1]=f69,-256
;;
stf.spill.nta [loc0]=f61,-256
stf.spill.nta [loc1]=f53,-256
adds loc2=96*16-64,in0
;;
stf.spill.nta [loc0]=f45,-256
stf.spill.nta [loc1]=f37,-256
adds loc3=96*16-64-128,in0
;;
stf.spill.nta [loc2]=f124,-256
stf.spill.nta [loc3]=f116,-256
;;
stf.spill.nta [loc2]=f108,-256
stf.spill.nta [loc3]=f100,-256
;;
stf.spill.nta [loc2]=f92,-256
stf.spill.nta [loc3]=f84,-256
;;
stf.spill.nta [loc2]=f76,-256
stf.spill.nta [loc3]=f68,-256
;;
stf.spill.nta [loc2]=f60,-256
stf.spill.nta [loc3]=f52,-256
adds loc0=96*16-80,in0
;;
stf.spill.nta [loc2]=f44,-256
stf.spill.nta [loc3]=f36,-256
adds loc1=96*16-80-128,in0
;;
stf.spill.nta [loc0]=f123,-256
stf.spill.nta [loc1]=f115,-256
;;
stf.spill.nta [loc0]=f107,-256
stf.spill.nta [loc1]=f99,-256
;;
stf.spill.nta [loc0]=f91,-256
stf.spill.nta [loc1]=f83,-256
;;
stf.spill.nta [loc0]=f75,-256
stf.spill.nta [loc1]=f67,-256
;;
stf.spill.nta [loc0]=f59,-256
stf.spill.nta [loc1]=f51,-256
adds loc2=96*16-96,in0
;;
stf.spill.nta [loc0]=f43,-256
stf.spill.nta [loc1]=f35,-256
adds loc3=96*16-96-128,in0
;;
stf.spill.nta [loc2]=f122,-256
stf.spill.nta [loc3]=f114,-256
;;
stf.spill.nta [loc2]=f106,-256
stf.spill.nta [loc3]=f98,-256
;;
stf.spill.nta [loc2]=f90,-256
stf.spill.nta [loc3]=f82,-256
;;
stf.spill.nta [loc2]=f74,-256
stf.spill.nta [loc3]=f66,-256
;;
stf.spill.nta [loc2]=f58,-256
stf.spill.nta [loc3]=f50,-256
adds loc0=96*16-112,in0
;;
stf.spill.nta [loc2]=f42,-256
stf.spill.nta [loc3]=f34,-256
adds loc1=96*16-112-128,in0
;;
stf.spill.nta [loc0]=f121,-256
stf.spill.nta [loc1]=f113,-256
;;
stf.spill.nta [loc0]=f105,-256
stf.spill.nta [loc1]=f97,-256
;;
stf.spill.nta [loc0]=f89,-256
stf.spill.nta [loc1]=f81,-256
;;
stf.spill.nta [loc0]=f73,-256
stf.spill.nta [loc1]=f65,-256
;;
stf.spill.nta [loc0]=f57,-256
stf.spill.nta [loc1]=f49,-256
adds loc2=96*16-128,in0
;;
stf.spill.nta [loc0]=f41,-256
stf.spill.nta [loc1]=f33,-256
adds loc3=96*16-128-128,in0
;;
stf.spill.nta [loc2]=f120,-256
stf.spill.nta [loc3]=f112,-256
;;
stf.spill.nta [loc2]=f104,-256
stf.spill.nta [loc3]=f96,-256
;;
stf.spill.nta [loc2]=f88,-256
stf.spill.nta [loc3]=f80,-256
;;
stf.spill.nta [loc2]=f72,-256
stf.spill.nta [loc3]=f64,-256
;;
stf.spill.nta [loc2]=f56,-256
stf.spill.nta [loc3]=f48,-256
;;
stf.spill.nta [loc2]=f40
stf.spill.nta [loc3]=f32
br.ret.sptk.many rp
END(__ia64_save_fpu)
GLOBAL_ENTRY(__ia64_load_fpu)
alloc r2=ar.pfs,1,2,0,0
adds r3=128,in0
adds r14=256,in0
adds r15=384,in0
mov loc0=512
mov loc1=-1024+16
;;
ldf.fill.nta f32=[in0],loc0
ldf.fill.nta f40=[ r3],loc0
ldf.fill.nta f48=[r14],loc0
ldf.fill.nta f56=[r15],loc0
;;
ldf.fill.nta f64=[in0],loc0
ldf.fill.nta f72=[ r3],loc0
ldf.fill.nta f80=[r14],loc0
ldf.fill.nta f88=[r15],loc0
;;
ldf.fill.nta f96=[in0],loc1
ldf.fill.nta f104=[ r3],loc1
ldf.fill.nta f112=[r14],loc1
ldf.fill.nta f120=[r15],loc1
;;
ldf.fill.nta f33=[in0],loc0
ldf.fill.nta f41=[ r3],loc0
ldf.fill.nta f49=[r14],loc0
ldf.fill.nta f57=[r15],loc0
;;
ldf.fill.nta f65=[in0],loc0
ldf.fill.nta f73=[ r3],loc0
ldf.fill.nta f81=[r14],loc0
ldf.fill.nta f89=[r15],loc0
;;
ldf.fill.nta f97=[in0],loc1
ldf.fill.nta f105=[ r3],loc1
ldf.fill.nta f113=[r14],loc1
ldf.fill.nta f121=[r15],loc1
;;
ldf.fill.nta f34=[in0],loc0
ldf.fill.nta f42=[ r3],loc0
ldf.fill.nta f50=[r14],loc0
ldf.fill.nta f58=[r15],loc0
;;
ldf.fill.nta f66=[in0],loc0
ldf.fill.nta f74=[ r3],loc0
ldf.fill.nta f82=[r14],loc0
ldf.fill.nta f90=[r15],loc0
;;
ldf.fill.nta f98=[in0],loc1
ldf.fill.nta f106=[ r3],loc1
ldf.fill.nta f114=[r14],loc1
ldf.fill.nta f122=[r15],loc1
;;
ldf.fill.nta f35=[in0],loc0
ldf.fill.nta f43=[ r3],loc0
ldf.fill.nta f51=[r14],loc0
ldf.fill.nta f59=[r15],loc0
;;
ldf.fill.nta f67=[in0],loc0
ldf.fill.nta f75=[ r3],loc0
ldf.fill.nta f83=[r14],loc0
ldf.fill.nta f91=[r15],loc0
;;
ldf.fill.nta f99=[in0],loc1
ldf.fill.nta f107=[ r3],loc1
ldf.fill.nta f115=[r14],loc1
ldf.fill.nta f123=[r15],loc1
;;
ldf.fill.nta f36=[in0],loc0
ldf.fill.nta f44=[ r3],loc0
ldf.fill.nta f52=[r14],loc0
ldf.fill.nta f60=[r15],loc0
;;
ldf.fill.nta f68=[in0],loc0
ldf.fill.nta f76=[ r3],loc0
ldf.fill.nta f84=[r14],loc0
ldf.fill.nta f92=[r15],loc0
;;
ldf.fill.nta f100=[in0],loc1
ldf.fill.nta f108=[ r3],loc1
ldf.fill.nta f116=[r14],loc1
ldf.fill.nta f124=[r15],loc1
;;
ldf.fill.nta f37=[in0],loc0
ldf.fill.nta f45=[ r3],loc0
ldf.fill.nta f53=[r14],loc0
ldf.fill.nta f61=[r15],loc0
;;
ldf.fill.nta f69=[in0],loc0
ldf.fill.nta f77=[ r3],loc0
ldf.fill.nta f85=[r14],loc0
ldf.fill.nta f93=[r15],loc0
;;
ldf.fill.nta f101=[in0],loc1
ldf.fill.nta f109=[ r3],loc1
ldf.fill.nta f117=[r14],loc1
ldf.fill.nta f125=[r15],loc1
;;
ldf.fill.nta f38 =[in0],loc0
ldf.fill.nta f46 =[ r3],loc0
ldf.fill.nta f54 =[r14],loc0
ldf.fill.nta f62 =[r15],loc0
;;
ldf.fill.nta f70 =[in0],loc0
ldf.fill.nta f78 =[ r3],loc0
ldf.fill.nta f86 =[r14],loc0
ldf.fill.nta f94 =[r15],loc0
;;
ldf.fill.nta f102=[in0],loc1
ldf.fill.nta f110=[ r3],loc1
ldf.fill.nta f118=[r14],loc1
ldf.fill.nta f126=[r15],loc1
;;
ldf.fill.nta f39 =[in0],loc0
ldf.fill.nta f47 =[ r3],loc0
ldf.fill.nta f55 =[r14],loc0
ldf.fill.nta f63 =[r15],loc0
;;
ldf.fill.nta f71 =[in0],loc0
ldf.fill.nta f79 =[ r3],loc0
ldf.fill.nta f87 =[r14],loc0
ldf.fill.nta f95 =[r15],loc0
;;
ldf.fill.nta f103=[in0]
ldf.fill.nta f111=[ r3]
ldf.fill.nta f119=[r14]
ldf.fill.nta f127=[r15]
br.ret.sptk.many rp
END(__ia64_load_fpu)
GLOBAL_ENTRY(__ia64_init_fpu)
stf.spill [sp]=f0 // M3
mov f32=f0 // F
nop.b 0
ldfps f33,f34=[sp] // M0
ldfps f35,f36=[sp] // M1
mov f37=f0 // F
;;
setf.s f38=r0 // M2
setf.s f39=r0 // M3
mov f40=f0 // F
ldfps f41,f42=[sp] // M0
ldfps f43,f44=[sp] // M1
mov f45=f0 // F
setf.s f46=r0 // M2
setf.s f47=r0 // M3
mov f48=f0 // F
ldfps f49,f50=[sp] // M0
ldfps f51,f52=[sp] // M1
mov f53=f0 // F
setf.s f54=r0 // M2
setf.s f55=r0 // M3
mov f56=f0 // F
ldfps f57,f58=[sp] // M0
ldfps f59,f60=[sp] // M1
mov f61=f0 // F
setf.s f62=r0 // M2
setf.s f63=r0 // M3
mov f64=f0 // F
ldfps f65,f66=[sp] // M0
ldfps f67,f68=[sp] // M1
mov f69=f0 // F
setf.s f70=r0 // M2
setf.s f71=r0 // M3
mov f72=f0 // F
ldfps f73,f74=[sp] // M0
ldfps f75,f76=[sp] // M1
mov f77=f0 // F
setf.s f78=r0 // M2
setf.s f79=r0 // M3
mov f80=f0 // F
ldfps f81,f82=[sp] // M0
ldfps f83,f84=[sp] // M1
mov f85=f0 // F
setf.s f86=r0 // M2
setf.s f87=r0 // M3
mov f88=f0 // F
/*
* When the instructions are cached, it would be faster to initialize
* the remaining registers with simply mov instructions (F-unit).
* This gets the time down to ~29 cycles. However, this would use up
* 33 bundles, whereas continuing with the above pattern yields
* 10 bundles and ~30 cycles.
*/
ldfps f89,f90=[sp] // M0
ldfps f91,f92=[sp] // M1
mov f93=f0 // F
setf.s f94=r0 // M2
setf.s f95=r0 // M3
mov f96=f0 // F
ldfps f97,f98=[sp] // M0
ldfps f99,f100=[sp] // M1
mov f101=f0 // F
setf.s f102=r0 // M2
setf.s f103=r0 // M3
mov f104=f0 // F
ldfps f105,f106=[sp] // M0
ldfps f107,f108=[sp] // M1
mov f109=f0 // F
setf.s f110=r0 // M2
setf.s f111=r0 // M3
mov f112=f0 // F
ldfps f113,f114=[sp] // M0
ldfps f115,f116=[sp] // M1
mov f117=f0 // F
setf.s f118=r0 // M2
setf.s f119=r0 // M3
mov f120=f0 // F
ldfps f121,f122=[sp] // M0
ldfps f123,f124=[sp] // M1
mov f125=f0 // F
setf.s f126=r0 // M2
setf.s f127=r0 // M3
br.ret.sptk.many rp // F
END(__ia64_init_fpu)
/*
* Switch execution mode from virtual to physical
*
* Inputs:
* r16 = new psr to establish
* Output:
* r19 = old virtual address of ar.bsp
* r20 = old virtual address of sp
*
* Note: RSE must already be in enforced lazy mode
*/
GLOBAL_ENTRY(ia64_switch_mode_phys)
{
rsm psr.i | psr.ic // disable interrupts and interrupt collection
mov r15=ip
}
;;
{
flushrs // must be first insn in group
srlz.i
}
;;
mov cr.ipsr=r16 // set new PSR
add r3=1f-ia64_switch_mode_phys,r15
mov r19=ar.bsp
mov r20=sp
mov r14=rp // get return address into a general register
;;
// going to physical mode, use tpa to translate virt->phys
tpa r17=r19
tpa r3=r3
tpa sp=sp
tpa r14=r14
;;
mov r18=ar.rnat // save ar.rnat
mov ar.bspstore=r17 // this steps on ar.rnat
mov cr.iip=r3
mov cr.ifs=r0
;;
mov ar.rnat=r18 // restore ar.rnat
rfi // must be last insn in group
;;
1: mov rp=r14
br.ret.sptk.many rp
END(ia64_switch_mode_phys)
/*
* Switch execution mode from physical to virtual
*
* Inputs:
* r16 = new psr to establish
* r19 = new bspstore to establish
* r20 = new sp to establish
*
* Note: RSE must already be in enforced lazy mode
*/
GLOBAL_ENTRY(ia64_switch_mode_virt)
{
rsm psr.i | psr.ic // disable interrupts and interrupt collection
mov r15=ip
}
;;
{
flushrs // must be first insn in group
srlz.i
}
;;
mov cr.ipsr=r16 // set new PSR
add r3=1f-ia64_switch_mode_virt,r15
mov r14=rp // get return address into a general register
;;
// going to virtual
// - for code addresses, set upper bits of addr to KERNEL_START
// - for stack addresses, copy from input argument
movl r18=KERNEL_START
dep r3=0,r3,KERNEL_TR_PAGE_SHIFT,64-KERNEL_TR_PAGE_SHIFT
dep r14=0,r14,KERNEL_TR_PAGE_SHIFT,64-KERNEL_TR_PAGE_SHIFT
mov sp=r20
;;
or r3=r3,r18
or r14=r14,r18
;;
mov r18=ar.rnat // save ar.rnat
mov ar.bspstore=r19 // this steps on ar.rnat
mov cr.iip=r3
mov cr.ifs=r0
;;
mov ar.rnat=r18 // restore ar.rnat
rfi // must be last insn in group
;;
1: mov rp=r14
br.ret.sptk.many rp
END(ia64_switch_mode_virt)
GLOBAL_ENTRY(ia64_delay_loop)
.prologue
{ nop 0 // work around GAS unwind info generation bug...
.save ar.lc,r2
mov r2=ar.lc
.body
;;
mov ar.lc=r32
}
;;
// force loop to be 32-byte aligned (GAS bug means we cannot use .align
// inside function body without corrupting unwind info).
{ nop 0 }
1: br.cloop.sptk.few 1b
;;
mov ar.lc=r2
br.ret.sptk.many rp
END(ia64_delay_loop)
/*
* Return a CPU-local timestamp in nano-seconds. This timestamp is
* NOT synchronized across CPUs its return value must never be
* compared against the values returned on another CPU. The usage in
* kernel/sched/core.c ensures that.
*
* The return-value of sched_clock() is NOT supposed to wrap-around.
* If it did, it would cause some scheduling hiccups (at the worst).
* Fortunately, with a 64-bit cycle-counter ticking at 100GHz, even
* that would happen only once every 5+ years.
*
* The code below basically calculates:
*
* (ia64_get_itc() * local_cpu_data->nsec_per_cyc) >> IA64_NSEC_PER_CYC_SHIFT
*
* except that the multiplication and the shift are done with 128-bit
* intermediate precision so that we can produce a full 64-bit result.
*/
GLOBAL_ENTRY(ia64_native_sched_clock)
addl r8=THIS_CPU(ia64_cpu_info) + IA64_CPUINFO_NSEC_PER_CYC_OFFSET,r0
mov.m r9=ar.itc // fetch cycle-counter (35 cyc)
;;
ldf8 f8=[r8]
;;
setf.sig f9=r9 // certain to stall, so issue it _after_ ldf8...
;;
xmpy.lu f10=f9,f8 // calculate low 64 bits of 128-bit product (4 cyc)
xmpy.hu f11=f9,f8 // calculate high 64 bits of 128-bit product
;;
getf.sig r8=f10 // (5 cyc)
getf.sig r9=f11
;;
shrp r8=r9,r8,IA64_NSEC_PER_CYC_SHIFT
br.ret.sptk.many rp
END(ia64_native_sched_clock)
cputime: Generic on-demand virtual cputime accounting If we want to stop the tick further idle, we need to be able to account the cputime without using the tick. Virtual based cputime accounting solves that problem by hooking into kernel/user boundaries. However implementing CONFIG_VIRT_CPU_ACCOUNTING require low level hooks and involves more overhead. But we already have a generic context tracking subsystem that is required for RCU needs by archs which plan to shut down the tick outside idle. This patch implements a generic virtual based cputime accounting that relies on these generic kernel/user hooks. There are some upsides of doing this: - This requires no arch code to implement CONFIG_VIRT_CPU_ACCOUNTING if context tracking is already built (already necessary for RCU in full tickless mode). - We can rely on the generic context tracking subsystem to dynamically (de)activate the hooks, so that we can switch anytime between virtual and tick based accounting. This way we don't have the overhead of the virtual accounting when the tick is running periodically. And one downside: - There is probably more overhead than a native virtual based cputime accounting. But this relies on hooks that are already set anyway. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Namhyung Kim <namhyung.kim@lge.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de>
2012-07-25 12:56:04 +07:00
#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
GLOBAL_ENTRY(cycle_to_nsec)
alloc r16=ar.pfs,1,0,0,0
addl r8=THIS_CPU(ia64_cpu_info) + IA64_CPUINFO_NSEC_PER_CYC_OFFSET,r0
;;
ldf8 f8=[r8]
;;
setf.sig f9=r32
;;
xmpy.lu f10=f9,f8 // calculate low 64 bits of 128-bit product (4 cyc)
xmpy.hu f11=f9,f8 // calculate high 64 bits of 128-bit product
;;
getf.sig r8=f10 // (5 cyc)
getf.sig r9=f11
;;
shrp r8=r9,r8,IA64_NSEC_PER_CYC_SHIFT
br.ret.sptk.many rp
END(cycle_to_nsec)
cputime: Generic on-demand virtual cputime accounting If we want to stop the tick further idle, we need to be able to account the cputime without using the tick. Virtual based cputime accounting solves that problem by hooking into kernel/user boundaries. However implementing CONFIG_VIRT_CPU_ACCOUNTING require low level hooks and involves more overhead. But we already have a generic context tracking subsystem that is required for RCU needs by archs which plan to shut down the tick outside idle. This patch implements a generic virtual based cputime accounting that relies on these generic kernel/user hooks. There are some upsides of doing this: - This requires no arch code to implement CONFIG_VIRT_CPU_ACCOUNTING if context tracking is already built (already necessary for RCU in full tickless mode). - We can rely on the generic context tracking subsystem to dynamically (de)activate the hooks, so that we can switch anytime between virtual and tick based accounting. This way we don't have the overhead of the virtual accounting when the tick is running periodically. And one downside: - There is probably more overhead than a native virtual based cputime accounting. But this relies on hooks that are already set anyway. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Namhyung Kim <namhyung.kim@lge.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de>
2012-07-25 12:56:04 +07:00
#endif /* CONFIG_VIRT_CPU_ACCOUNTING_NATIVE */
#ifdef CONFIG_IA64_BRL_EMU
/*
* Assembly routines used by brl_emu.c to set preserved register state.
*/
#define SET_REG(reg) \
GLOBAL_ENTRY(ia64_set_##reg); \
alloc r16=ar.pfs,1,0,0,0; \
mov reg=r32; \
;; \
br.ret.sptk.many rp; \
END(ia64_set_##reg)
SET_REG(b1);
SET_REG(b2);
SET_REG(b3);
SET_REG(b4);
SET_REG(b5);
#endif /* CONFIG_IA64_BRL_EMU */
#ifdef CONFIG_SMP
#ifdef CONFIG_HOTPLUG_CPU
GLOBAL_ENTRY(ia64_jump_to_sal)
alloc r16=ar.pfs,1,0,0,0;;
rsm psr.i | psr.ic
{
flushrs
srlz.i
}
tpa r25=in0
movl r18=tlb_purge_done;;
DATA_VA_TO_PA(r18);;
mov b1=r18 // Return location
movl r18=ia64_do_tlb_purge;;
DATA_VA_TO_PA(r18);;
mov b2=r18 // doing tlb_flush work
mov ar.rsc=0 // Put RSE in enforced lazy, LE mode
movl r17=1f;;
DATA_VA_TO_PA(r17);;
mov cr.iip=r17
movl r16=SAL_PSR_BITS_TO_SET;;
mov cr.ipsr=r16
mov cr.ifs=r0;;
[IA64] kdump: Mask MCA/INIT on frozen cpus Summary: INIT asserted on kdump kernel invokes INIT handler not only on a cpu that running on the kdump kernel, but also BSP of the panicked kernel, because the (badly) frozen BSP can be thawed by INIT. Description: The kdump_cpu_freeze() is called on cpus except one that initiates panic and/or kdump, to stop/offline the cpu (on ia64, it means we pass control of cpus to SAL, or put them in spinloop). Note that CPU0(BSP) always go to spinloop, so if panic was happened on an AP, there are at least 2cpus (= the AP and BSP) which not back to SAL. On the spinning cpus, interrupts are disabled (rsm psr.i), but INIT is still interruptible because psr.mc for mask them is not set unless kdump_cpu_freeze() is not called from MCA/INIT context. Therefore, assume that a panic was happened on an AP, kdump was invoked, new INIT handlers for kdump kernel was registered and then an INIT is asserted. From the viewpoint of SAL, there are 2 online cpus, so INIT will be delivered to both of them. It likely means that not only the AP (= a cpu executing kdump) enters INIT handler which is newly registered, but also BSP (= another cpu spinning in panicked kernel) enters the same INIT handler. Of course setting of registers in BSP are still old (for panicked kernel), so what happen with running handler with wrong setting will be extremely unexpected. I believe this is not desirable behavior. How to Reproduce: Start kdump on one of APs (e.g. cpu1) # taskset 0x2 echo c > /proc/sysrq-trigger Then assert INIT after kdump kernel is booted, after new INIT handler for kdump kernel is registered. Expected results: An INIT handler is invoked only on the AP. Actual results: An INIT handler is invoked on the AP and BSP. Sample of results: I got following console log by asserting INIT after prompt "root:/>". It seems that two monarchs appeared by one INIT, and one panicked at last. And it also seems that the panicked one supposed there were 4 online cpus and no one did rendezvous: : [ 0 %]dropping to initramfs shell exiting this shell will reboot your system root:/> Entered OS INIT handler. PSP=fff301a0 cpu=0 monarch=0 ia64_init_handler: Promoting cpu 0 to monarch. Delaying for 5 seconds... All OS INIT slaves have reached rendezvous Processes interrupted by INIT - 0 (cpu 0 task 0xa000000100af0000) : <<snip>> : Entered OS INIT handler. PSP=fff301a0 cpu=0 monarch=1 Delaying for 5 seconds... mlogbuf_finish: printing switched to urgent mode, MCA/INIT might be dodgy or fail. OS INIT slave did not rendezvous on cpu 1 2 3 INIT swapper 0[0]: bugcheck! 0 [1] : <<snip>> : Kernel panic - not syncing: Attempted to kill the idle task! Proposed fix: To avoid this problem, this patch inserts ia64_set_psr_mc() to mask INIT on cpus going to be frozen. This masking have no effect if the kdump_cpu_freeze() is called from INIT handler when kdump_on_init == 1, because psr.mc is already turned on to 1 before entering OS_INIT. I confirmed that weird log like above are disappeared after applying this patch. Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Haren Myneni <hbabu@us.ibm.com> Cc: kexec@lists.infradead.org Acked-by: Fenghua Yu <fenghua.yu@intel.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
2009-08-07 04:51:56 +07:00
rfi;; // note: this unmask MCA/INIT (psr.mc)
1:
/*
* Invalidate all TLB data/inst
*/
br.sptk.many b2;; // jump to tlb purge code
tlb_purge_done:
RESTORE_REGION_REGS(r25, r17,r18,r19);;
RESTORE_REG(b0, r25, r17);;
RESTORE_REG(b1, r25, r17);;
RESTORE_REG(b2, r25, r17);;
RESTORE_REG(b3, r25, r17);;
RESTORE_REG(b4, r25, r17);;
RESTORE_REG(b5, r25, r17);;
ld8 r1=[r25],0x08;;
ld8 r12=[r25],0x08;;
ld8 r13=[r25],0x08;;
RESTORE_REG(ar.fpsr, r25, r17);;
RESTORE_REG(ar.pfs, r25, r17);;
RESTORE_REG(ar.rnat, r25, r17);;
RESTORE_REG(ar.unat, r25, r17);;
RESTORE_REG(ar.bspstore, r25, r17);;
RESTORE_REG(cr.dcr, r25, r17);;
RESTORE_REG(cr.iva, r25, r17);;
RESTORE_REG(cr.pta, r25, r17);;
srlz.d;; // required not to violate RAW dependency
RESTORE_REG(cr.itv, r25, r17);;
RESTORE_REG(cr.pmv, r25, r17);;
RESTORE_REG(cr.cmcv, r25, r17);;
RESTORE_REG(cr.lrr0, r25, r17);;
RESTORE_REG(cr.lrr1, r25, r17);;
ld8 r4=[r25],0x08;;
ld8 r5=[r25],0x08;;
ld8 r6=[r25],0x08;;
ld8 r7=[r25],0x08;;
ld8 r17=[r25],0x08;;
mov pr=r17,-1;;
RESTORE_REG(ar.lc, r25, r17);;
/*
* Now Restore floating point regs
*/
ldf.fill.nta f2=[r25],16;;
ldf.fill.nta f3=[r25],16;;
ldf.fill.nta f4=[r25],16;;
ldf.fill.nta f5=[r25],16;;
ldf.fill.nta f16=[r25],16;;
ldf.fill.nta f17=[r25],16;;
ldf.fill.nta f18=[r25],16;;
ldf.fill.nta f19=[r25],16;;
ldf.fill.nta f20=[r25],16;;
ldf.fill.nta f21=[r25],16;;
ldf.fill.nta f22=[r25],16;;
ldf.fill.nta f23=[r25],16;;
ldf.fill.nta f24=[r25],16;;
ldf.fill.nta f25=[r25],16;;
ldf.fill.nta f26=[r25],16;;
ldf.fill.nta f27=[r25],16;;
ldf.fill.nta f28=[r25],16;;
ldf.fill.nta f29=[r25],16;;
ldf.fill.nta f30=[r25],16;;
ldf.fill.nta f31=[r25],16;;
/*
* Now that we have done all the register restores
* we are now ready for the big DIVE to SAL Land
*/
ssm psr.ic;;
srlz.d;;
br.ret.sptk.many b0;;
END(ia64_jump_to_sal)
#endif /* CONFIG_HOTPLUG_CPU */
#endif /* CONFIG_SMP */