Commit Graph

59 Commits

Author SHA1 Message Date
YueHaibing d273fa919c powerpc/pseries: Use correct event modifier in rtas_parse_epow_errlog()
rtas_parse_epow_errlog() should pass 'modifier' to
handle_system_shutdown, because event modifier only use
bottom 4 bits.

Reviewed-by: Tyrel Datwyler <tyreld@linux.ibm.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191023134838.21280-1-yuehaibing@huawei.com
2019-11-13 16:58:04 +11:00
Nicholas Piggin 9ca766f989 powerpc/64s/pseries: machine check convert to use common event code
The common machine_check_event data structures and queues are mostly
platform independent, with powernv decoding SRR1/DSISR/etc., into
machine_check_event objects.

This patch converts pseries to use this infrastructure by decoding
fwnmi/rtas data into machine_check_event objects.

This allows queueing to be used by a subsequent change to delay the
virtual mode handling of machine checks that occur in kernel space
where it is unsafe to switch immediately to virtual mode, similarly
to powernv.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Fix implicit fallthrough warnings in mce_handle_error()]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190802105709.27696-10-npiggin@gmail.com
2019-08-30 10:32:35 +10:00
Thomas Gleixner 1a59d1b8e0 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version this program is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details you
  should have received a copy of the gnu general public license along
  with this program if not write to the free software foundation inc
  59 temple place suite 330 boston ma 02111 1307 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1334 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:35 -07:00
Ganesh Goudar 7f177f9810 powerpc/pseries: hwpoison the pages upon hitting UE
Add support to hwpoison the pages upon hitting machine check
exception.

This patch queues the address where UE is hit to percpu array
and schedules work to plumb it into memory poison infrastructure.

Reviewed-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Ganesh Goudar <ganeshgr@linux.ibm.com>
[mpe: Combine #ifdefs, drop PPC_BIT8(), and empty inline stub]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-04-20 22:02:35 +10:00
Mahesh Salgaonkar c9d8dda423 powerpc/pseries/mce: Improve array initialization.
This is a follow up to the patch that fixed misleading print for TLB
mutlihit due to wrongly populated mc_err_types[] array. Convert all the
static array initialization to '[x] = val' style for better
readability of array indexing and avoid any further confusion.

Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-04-20 22:02:26 +10:00
Mahesh Salgaonkar 6f845ebec2 powerpc/pseries/mce: Fix misleading print for TLB mutlihit
On pseries, TLB multihit are reported as D-Cache Multihit. This is because
the wrongly populated mc_err_types[] array. Per PAPR, TLB error type is 0x04
and mc_err_types[4] points to "D-Cache" instead of "TLB" string. Fixup the
mc_err_types[] array.

Machine check error type per PAPR:
  0x00 = Uncorrectable Memory Error (UE)
  0x01 = SLB error
  0x02 = ERAT Error
  0x04 = TLB error
  0x05 = D-Cache error
  0x07 = I-Cache error

Fixes: 8f0b80561f ("powerpc/pseries: Display machine check error details.")
Cc: stable@vger.kernel.org # v4.20+
Reported-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-03-29 16:59:19 +11:00
Oliver O'Halloran 4c5d87db49 powerpc/pseries: PAPR persistent memory support
This patch implements support for discovering storage class memory
devices at boot and for handling hotplug of new regions via RTAS
hotplug events.

Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
[mpe: Fix CONFIG_MEMORY_HOTPLUG=n build]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-19 00:56:17 +11:00
Nathan Fontenot fd12527a1d powerpc/pseries: Remove unneeded uses of dlpar work queue
There are three instances in which dlpar hotplug events are invoked;
handling a hotplug interrupt (in a kvm guest), handling a dlpar
request through sysfs, and updating LMB affinity when handling a
PRRN event. Only in the case of handling a hotplug interrupt do we
have to put the work on a workqueue, the other cases can handle the
dlpar request directly.

This patch exports the handle_dlpar_errorlog() function so that
dlpar hotplug events can be handled directly and updates the two
instances mentioned above to use the direct invocation.

Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-09-19 22:08:12 +10:00
Mahesh Salgaonkar c6d15258cd powerpc/pseries: Dump the SLB contents on SLB MCE errors.
If we get a machine check exceptions due to SLB errors then dump the
current SLB contents which will be very much helpful in debugging the
root cause of SLB errors. Introduce an exclusive buffer per cpu to hold
faulty SLB entries. In real mode mce handler saves the old SLB contents
into this buffer accessible through paca and print it out later in virtual
mode.

With this patch the console will log SLB contents like below on SLB MCE
errors:

[  507.297236] SLB contents of cpu 0x1
[  507.297237] Last SLB entry inserted at slot 16
[  507.297238] 00 c000000008000000 400ea1b217000500
[  507.297239]   1T  ESID=   c00000  VSID=      ea1b217 LLP:100
[  507.297240] 01 d000000008000000 400d43642f000510
[  507.297242]   1T  ESID=   d00000  VSID=      d43642f LLP:110
[  507.297243] 11 f000000008000000 400a86c85f000500
[  507.297244]   1T  ESID=   f00000  VSID=      a86c85f LLP:100
[  507.297245] 12 00007f0008000000 4008119624000d90
[  507.297246]   1T  ESID=       7f  VSID=      8119624 LLP:110
[  507.297247] 13 0000000018000000 00092885f5150d90
[  507.297247]  256M ESID=        1  VSID=   92885f5150 LLP:110
[  507.297248] 14 0000010008000000 4009e7cb50000d90
[  507.297249]   1T  ESID=        1  VSID=      9e7cb50 LLP:110
[  507.297250] 15 d000000008000000 400d43642f000510
[  507.297251]   1T  ESID=   d00000  VSID=      d43642f LLP:110
[  507.297252] 16 d000000008000000 400d43642f000510
[  507.297253]   1T  ESID=   d00000  VSID=      d43642f LLP:110
[  507.297253] ----------------------------------
[  507.297254] SLB cache ptr value = 3
[  507.297254] Valid SLB cache entries:
[  507.297255] 00 EA[0-35]=    7f000
[  507.297256] 01 EA[0-35]=        1
[  507.297257] 02 EA[0-35]=     1000
[  507.297257] Rest of SLB cache entries:
[  507.297258] 03 EA[0-35]=    7f000
[  507.297258] 04 EA[0-35]=        1
[  507.297259] 05 EA[0-35]=     1000
[  507.297260] 06 EA[0-35]=       12
[  507.297260] 07 EA[0-35]=    7f000

Suggested-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-09-19 21:59:41 +10:00
Mahesh Salgaonkar 8f0b80561f powerpc/pseries: Display machine check error details.
Extract the MCE error details from RTAS extended log and display it to
console.

With this patch you should now see mce logs like below:

[  142.371818] Severe Machine check interrupt [Recovered]
[  142.371822]   NIP [d00000000ca301b8]: init_module+0x1b8/0x338 [bork_kernel]
[  142.371822]   Initiator: CPU
[  142.371823]   Error type: SLB [Multihit]
[  142.371824]     Effective address: d00000000ca70000

Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-09-19 21:59:41 +10:00
Mahesh Salgaonkar a43c159042 powerpc/pseries: Flush SLB contents on SLB MCE errors.
On pseries, as of today system crashes if we get a machine check
exceptions due to SLB errors. These are soft errors and can be fixed
by flushing the SLBs so the kernel can continue to function instead of
system crash. We do this in real mode before turning on MMU. Otherwise
we would run into nested machine checks. This patch now fetches the
rtas error log in real mode and flushes the SLBs on SLB/ERAT errors.

Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Michal Suchanek <msuchanek@suse.com>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-09-19 21:59:22 +10:00
Mahesh Salgaonkar 04fce21c9d powerpc/pseries: Define MCE error event section.
On pseries, the machine check error details are part of RTAS extended
event log passed under Machine check exception section. This patch adds
the definition of rtas MCE event section and related helper
functions.

Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-09-19 21:58:09 +10:00
Mahesh Salgaonkar cd813e1cd7 powerpc/pseries: Fix endianness while restoring of r3 in MCE handler.
During Machine Check interrupt on pseries platform, register r3 points
RTAS extended event log passed by hypervisor. Since hypervisor uses r3
to pass pointer to rtas log, it stores the original r3 value at the
start of the memory (first 8 bytes) pointed by r3. Since hypervisor
stores this info and rtas log is in BE format, linux should make
sure to restore r3 value in correct endian format.

Without this patch when MCE handler, after recovery, returns to code that
that caused the MCE may end up with Data SLB access interrupt for invalid
address followed by kernel panic or hang.

  Severe Machine check interrupt [Recovered]
    NIP [d00000000ca301b8]: init_module+0x1b8/0x338 [bork_kernel]
    Initiator: CPU
    Error type: SLB [Multihit]
      Effective address: d00000000ca70000
  cpu 0xa: Vector: 380 (Data SLB Access) at [c0000000fc7775b0]
      pc: c0000000009694c0: vsnprintf+0x80/0x480
      lr: c0000000009698e0: vscnprintf+0x20/0x60
      sp: c0000000fc777830
     msr: 8000000002009033
     dar: a803a30c000000d0
    current = 0xc00000000bc9ef00
    paca    = 0xc00000001eca5c00	 softe: 3	 irq_happened: 0x01
      pid   = 8860, comm = insmod
  vscnprintf+0x20/0x60
  vprintk_emit+0xb4/0x4b0
  vprintk_func+0x5c/0xd0
  printk+0x38/0x4c
  init_module+0x1c0/0x338 [bork_kernel]
  do_one_initcall+0x54/0x230
  do_init_module+0x8c/0x248
  load_module+0x12b8/0x15b0
  sys_finit_module+0xa8/0x110
  system_call+0x58/0x6c
  --- Exception: c00 (System Call) at 00007fff8bda0644
  SP (7fffdfbfe980) is in userspace

This patch fixes this issue.

Fixes: a08a53ea4c ("powerpc/le: Enable RTAS events support")
Cc: stable@vger.kernel.org # v3.15+
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-08-10 22:12:34 +10:00
Mahesh Salgaonkar 94675cceac powerpc/pseries: Defer the logging of rtas error to irq work queue.
rtas_log_buf is a buffer to hold RTAS event data that are communicated
to kernel by hypervisor. This buffer is then used to pass RTAS event
data to user through proc fs. This buffer is allocated from
vmalloc (non-linear mapping) area.

On Machine check interrupt, register r3 points to RTAS extended event
log passed by hypervisor that contains the MCE event. The pseries
machine check handler then logs this error into rtas_log_buf. The
rtas_log_buf is a vmalloc-ed (non-linear) buffer we end up taking up a
page fault (vector 0x300) while accessing it. Since machine check
interrupt handler runs in NMI context we can not afford to take any
page fault. Page faults are not honored in NMI context and causes
kernel panic. Apart from that, as Nick pointed out,
pSeries_log_error() also takes a spin_lock while logging error which
is not safe in NMI context. It may endup in deadlock if we get another
MCE before releasing the lock. Fix this by deferring the logging of
rtas error to irq work queue.

Current implementation uses two different buffers to hold rtas error
log depending on whether extended log is provided or not. This makes
bit difficult to identify which buffer has valid data that needs to
logged later in irq work. Simplify this using single buffer, one per
paca, and copy rtas log to it irrespective of whether extended log is
provided or not. Allocate this buffer below RMA region so that it can
be accessed in real mode mce handler.

Fixes: b96672dd84 ("powerpc: Machine check interrupt is a non-maskable interrupt")
Cc: stable@vger.kernel.org # v4.14+
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-08-07 21:49:29 +10:00
Mahesh Salgaonkar 74e96bf44f powerpc/pseries: Avoid using the size greater than RTAS_ERROR_LOG_MAX.
The global mce data buffer that used to copy rtas error log is of 2048
(RTAS_ERROR_LOG_MAX) bytes in size. Before the copy we read
extended_log_length from rtas error log header, then use max of
extended_log_length and RTAS_ERROR_LOG_MAX as a size of data to be copied.
Ideally the platform (phyp) will never send extended error log with
size > 2048. But if that happens, then we have a risk of buffer overrun
and corruption. Fix this by using min_t instead.

Fixes: d368514c30 ("powerpc: Fix corruption when grabbing FWNMI data")
Reported-by: Michal Suchanek <msuchanek@suse.com>
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-08-07 21:49:28 +10:00
Sam Bobroff c9dccf1d07 powerpc/pseries: Enable RAS hotplug events later
Currently if the kernel receives a memory hot-unplug event early
enough, it may get stuck in an infinite loop in
dissolve_free_huge_pages(). This appears as a stall just after:

  pseries-hotplug-mem: Attempting to hot-remove XX LMB(s) at YYYYYYYY

It appears to be caused by "minimum_order" being uninitialized, due to
init_ras_IRQ() executing before hugetlb_init().

To correct this, extract the part of init_ras_IRQ() that enables
hotplug event processing and place it in the machine_late_initcall
phase, which is guaranteed to be after hugetlb_init() is called.

Signed-off-by: Sam Bobroff <sam.bobroff@au1.ibm.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
[mpe: Reorder the functions to make the diff readable]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-02-13 22:37:46 +11:00
Michael Ellerman e2d5915293 powerpc/pseries: Make RAS IRQ explicitly dependent on DLPAR WQ
The hotplug code uses its own workqueue to handle IRQ requests
(pseries_hp_wq), however that workqueue is initialized after
init_ras_IRQ(). That can lead to a kernel panic if any hotplug
interrupts fire after init_ras_IRQ() but before pseries_hp_wq is
initialised. eg:

  UDP-Lite hash table entries: 2048 (order: 0, 65536 bytes)
  NET: Registered protocol family 1
  Unpacking initramfs...
  (qemu) object_add memory-backend-ram,id=mem1,size=10G
  (qemu) device_add pc-dimm,id=dimm1,memdev=mem1
  Unable to handle kernel paging request for data at address 0xf94d03007c421378
  Faulting instruction address: 0xc00000000012d744
  Oops: Kernel access of bad area, sig: 11 [#1]
  LE SMP NR_CPUS=2048 NUMA pSeries
  Modules linked in:
  CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.15.0-rc2-ziviani+ #26
  task:         (ptrval) task.stack:         (ptrval)
  NIP:  c00000000012d744 LR: c00000000012d744 CTR: 0000000000000000
  REGS:         (ptrval) TRAP: 0380   Not tainted  (4.15.0-rc2-ziviani+)
  MSR:  8000000000009033 <SF,EE,ME,IR,DR,RI,LE>  CR: 28088042  XER: 20040000
  CFAR: c00000000012d3c4 SOFTE: 0
  ...
  NIP [c00000000012d744] __queue_work+0xd4/0x5c0
  LR [c00000000012d744] __queue_work+0xd4/0x5c0
  Call Trace:
  [c0000000fffefb90] [c00000000012d744] __queue_work+0xd4/0x5c0 (unreliable)
  [c0000000fffefc70] [c00000000012dce4] queue_work_on+0xb4/0xf0

This commit makes the RAS IRQ registration explicitly dependent on the
creation of the pseries_hp_wq.

Reported-by: Min Deng <mdeng@redhat.com>
Reported-by: Daniel Henrique Barboza <danielhb@linux.vnet.ibm.com>
Tested-by: Jose Ricardo Ziviani <joserz@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2018-01-08 14:54:32 +11:00
Nicholas Piggin bded070643 powerpc/pseries/le: Work around a firmware quirk
Some PowerVM firmware when delivering a system reset interrupt to a
little endian OS will mess up SRR registers. They are byteswapped, and
SRR1 is incorrect. An example from a crash:

  NIP: 14dd0900000000c0
  MSR: 1000000200000080

It's possible to detect this pattern in SRR1 (that would never happen
in normal operation), and at least fix the NIP. After this patch, the
same interrupt reports NIP properly:

  NIP [c00000000009dd14] plpar_hcall_norets+0x1c/0x28

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-31 14:26:02 +10:00
Nicholas Piggin 102c05e8dc powerpc/pseries: Implement NMI IPI with H_SIGNAL_SYS_RESET
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-28 21:02:25 +10:00
John Allen b7d9eb397b powerpc/pseries: Add support for hotplug interrupt source
Add handler for new hotplug interrupt. For memory and CPU hotplug events,
we will add the hotplug errorlog to the hotplug workqueue. Since PCI
hotplug is not currently supported in the kernel, PCI hotplug events are
written to the rtas_log_bug and are handled by rtas_errd.

Signed-off-by: John Allen <jallen@linux.vnet.ibm.com>
Reviewed-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-07-19 20:12:30 +10:00
Vipin K Parashar b4af279a7c powerpc/pseries: Limit EPOW reset event warnings
Kernel prints respective warnings about various EPOW events for
user information/action after parsing EPOW interrupts. At times
below EPOW reset event warning is seen to be flooding kernel log
over a period of time.

May 25 03:46:34 alp kernel: Non critical power or cooling issue cleared
May 25 03:46:52 alp kernel: Non critical power or cooling issue cleared
May 25 03:53:48 alp kernel: Non critical power or cooling issue cleared
May 25 03:55:46 alp kernel: Non critical power or cooling issue cleared
May 25 03:56:34 alp kernel: Non critical power or cooling issue cleared
May 25 03:59:04 alp kernel: Non critical power or cooling issue cleared
May 25 04:02:01 alp kernel: Non critical power or cooling issue cleared

These EPOW reset events are spurious in nature and are triggered by
firmware without an actual EPOW event being reset. This patch avoids these
multiple EPOW reset warnings by using a counter variable. This variable
is incremented every time an EPOW event is reported. Upon receiving a EPOW
reset event the same variable is checked to filter out spurious events and
decremented accordingly.

This patch also improves log messages to better describe EPOW event being
reported. Merged adjacent log messages into single one to reduce number of
lines printed per event.

Signed-off-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Signed-off-by: Vipin K Parashar <vipin@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-14 20:41:49 +11:00
Thomas Huth 1c2cb59444 powerpc/rtas: Introduce rtas_get_sensor_fast() for IRQ handlers
The EPOW interrupt handler uses rtas_get_sensor(), which in turn
uses rtas_busy_delay() to wait for RTAS becoming ready in case it
is necessary. But rtas_busy_delay() is annotated with might_sleep()
and thus may not be used by interrupts handlers like the EPOW handler!
This leads to the following BUG when CONFIG_DEBUG_ATOMIC_SLEEP is
enabled:

 BUG: sleeping function called from invalid context at arch/powerpc/kernel/rtas.c:496
 in_atomic(): 1, irqs_disabled(): 1, pid: 0, name: swapper/1
 CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.2.0-rc2-thuth #6
 Call Trace:
 [c00000007ffe7b90] [c000000000807670] dump_stack+0xa0/0xdc (unreliable)
 [c00000007ffe7bc0] [c0000000000e1f14] ___might_sleep+0x134/0x180
 [c00000007ffe7c20] [c00000000002aec0] rtas_busy_delay+0x30/0xd0
 [c00000007ffe7c50] [c00000000002bde4] rtas_get_sensor+0x74/0xe0
 [c00000007ffe7ce0] [c000000000083264] ras_epow_interrupt+0x44/0x450
 [c00000007ffe7d90] [c000000000120260] handle_irq_event_percpu+0xa0/0x300
 [c00000007ffe7e70] [c000000000120524] handle_irq_event+0x64/0xc0
 [c00000007ffe7eb0] [c000000000124dbc] handle_fasteoi_irq+0xec/0x260
 [c00000007ffe7ef0] [c00000000011f4f0] generic_handle_irq+0x50/0x80
 [c00000007ffe7f20] [c000000000010f3c] __do_irq+0x8c/0x200
 [c00000007ffe7f90] [c0000000000236cc] call_do_irq+0x14/0x24
 [c00000007e6f39e0] [c000000000011144] do_IRQ+0x94/0x110
 [c00000007e6f3a30] [c000000000002594] hardware_interrupt_common+0x114/0x180

Fix this issue by introducing a new rtas_get_sensor_fast() function
that does not use rtas_busy_delay() - and thus can only be used for
sensors that do not cause a BUSY condition - known as "fast" sensors.

The EPOW sensor is defined to be "fast" in sPAPR - mpe.

Fixes: 587f83e8dd ("powerpc/pseries: Use rtas_get_sensor in RAS code")
Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-07-23 19:43:11 +10:00
Anshuman Khandual 79872e3546 powerpc/pseries: All events of EPOW_SYSTEM_SHUTDOWN must initiate shutdown
The current handling of EPOW_SHUTDOWN_ON_UPS event does not shutdown the
system after logging the message. All the events of EPOW_SYSTEM_SHUTDOWN
action code (EPOW_SHUTDOWN_ON_UPS is a part of it) must initiate system
shutdown as per the SPAPR spec. If the LPAR does not shutdown after
receiving this rtas based event, it will expose itself to a forced
abrupt shutdown initiated by the platform firmware. This patch fixes the
situation.

Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-01-23 11:17:30 +11:00
Christoph Lameter 69111bac42 powerpc: Replace __get_cpu_var uses
This still has not been merged and now powerpc is the only arch that does
not have this change. Sorry about missing linuxppc-dev before.

V2->V2
  - Fix up to work against 3.18-rc1

__get_cpu_var() is used for multiple purposes in the kernel source. One of
them is address calculation via the form &__get_cpu_var(x).  This calculates
the address for the instance of the percpu variable of the current processor
based on an offset.

Other use cases are for storing and retrieving data from the current
processors percpu area.  __get_cpu_var() can be used as an lvalue when
writing data or on the right side of an assignment.

__get_cpu_var() is defined as :

__get_cpu_var() always only does an address determination. However, store
and retrieve operations could use a segment prefix (or global register on
other platforms) to avoid the address calculation.

this_cpu_write() and this_cpu_read() can directly take an offset into a
percpu area and use optimized assembly code to read and write per cpu
variables.

This patch converts __get_cpu_var into either an explicit address
calculation using this_cpu_ptr() or into a use of this_cpu operations that
use the offset.  Thereby address calculations are avoided and less registers
are used when code is generated.

At the end of the patch set all uses of __get_cpu_var have been removed so
the macro is removed too.

The patch set includes passes over all arches as well. Once these operations
are used throughout then specialized macros can be defined in non -x86
arches as well in order to optimize per cpu access by f.e.  using a global
register that may be set to the per cpu base.

Transformations done to __get_cpu_var()

1. Determine the address of the percpu instance of the current processor.

	DEFINE_PER_CPU(int, y);
	int *x = &__get_cpu_var(y);

    Converts to

	int *x = this_cpu_ptr(&y);

2. Same as #1 but this time an array structure is involved.

	DEFINE_PER_CPU(int, y[20]);
	int *x = __get_cpu_var(y);

    Converts to

	int *x = this_cpu_ptr(y);

3. Retrieve the content of the current processors instance of a per cpu
variable.

	DEFINE_PER_CPU(int, y);
	int x = __get_cpu_var(y)

   Converts to

	int x = __this_cpu_read(y);

4. Retrieve the content of a percpu struct

	DEFINE_PER_CPU(struct mystruct, y);
	struct mystruct x = __get_cpu_var(y);

   Converts to

	memcpy(&x, this_cpu_ptr(&y), sizeof(x));

5. Assignment to a per cpu variable

	DEFINE_PER_CPU(int, y)
	__get_cpu_var(y) = x;

   Converts to

	__this_cpu_write(y, x);

6. Increment/Decrement etc of a per cpu variable

	DEFINE_PER_CPU(int, y);
	__get_cpu_var(y)++

   Converts to

	__this_cpu_inc(y)

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
Signed-off-by: Christoph Lameter <cl@linux.com>
[mpe: Fix build errors caused by set/or_softirq_pending(), and rework
      assignment in __set_breakpoint() to use memcpy().]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-11-03 12:12:32 +11:00
Anton Blanchard e51df2c170 powerpc: Make a bunch of things static
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-25 23:14:41 +10:00
Michael Ellerman 8e83e9053f powerpc/pseries: Switch pseries drivers to use machine_xxx_initcall()
A lot of the code in platforms/pseries is using non-machine initcalls.
That means if a kernel built with pseries support runs on another
platform, for example powernv, the initcalls will still run.

Most of these cases are OK, though sometimes only due to luck. Some were
having more effect:

 * hcall_inst_init
  - Checking FW_FEATURE_LPAR which is set on ps3 & celleb.
 * mobility_sysfs_init
  - created sysfs files unconditionally
  - but no effect due to ENOSYS from rtas_ibm_suspend_me()
 * apo_pm_init
  - created sysfs, allows write
  - nothing checks the value written to though
 * alloc_dispatch_log_kmem_cache
  - creating kmem_cache on non-pseries machines

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-07-28 14:11:26 +10:00
Greg Kurz a08a53ea4c powerpc/le: Enable RTAS events support
The current kernel code assumes big endian and parses RTAS events all
wrong. The most visible effect is that we cannot honor EPOW events,
meaning, for example, we cannot shut down a guest properly from the
hypervisor.

This new patch is largely inspired by Nathan's work: we get rid of all
the bit fields in the RTAS event structures (even the unused ones, for
consistency). We also introduce endian safe accessors for the fields used
by the kernel (trivial rtas_error_type() accessor added for consistency).

Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-04-07 10:33:12 +10:00
Mahesh Salgaonkar ee1dd1e3dc powerpc: Fix the corrupt r3 error during MCE handling.
During Machine Check interrupt on pseries platform, R3 generally points to
memory region inside RTAS (FWNMI) area. We see r3 corruption because when RTAS
delivers the machine check exception it passes the address inside FWNMI area
with the top most bit set. This patch fixes this issue by masking top two bit
in machine check exception handler.

Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-07-24 14:18:45 +10:00
liguang 1b7e0cbe49 powerpc/pseries: Use 'true' instead of '1' for orderly_poweroff
orderly_poweroff is expecting a bool parameter, so
use 'true' instead '1'

Signed-off-by: liguang <lig.fnst@cn.fujitsu.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-06-20 17:04:26 +10:00
Anton Blanchard 9012899781 powerpc/pseries: Cut down on enthusiastic use of defines in RAS code
So many defines for such a little file. Most of them can go.

Also remove the single entry changelog, we have git for that.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-03-28 11:32:01 +11:00
Anton Blanchard cc8b526366 powerpc/pseries: Clean up ras_error_interrupt code
The RAS error interrupt is no longer used but we may as well
mirror the changes we made to the EPOW interrupt.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-03-28 11:32:00 +11:00
Anton Blanchard 6f43747f6a powerpc/pseries: Remove RTAS_POWERMGM_EVENTS
IBM bit 2 in the rtas event-scan and check-exception calls is
marked reserved in the PAPR, so remove it from our RAS code.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-03-28 11:32:00 +11:00
Anton Blanchard 587f83e8dd powerpc/pseries: Use rtas_get_sensor in RAS code
We have rtas_get_sensor so we may as well use it.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-03-28 11:31:59 +11:00
Anton Blanchard 55fc0c5617 powerpc/pseries: Parse and handle EPOW interrupts
We have code to take environmental and power warning (EPOW)
interrupts but it simply prints a terse error message:

EPOW <0x6240040000000b8 0x0 0x0>

which tells us nothing about what happened. Even worse, if we
don't correctly respond to the interrupt we may get terminated
by firmware.

Add code to printk some useful information when we get EPOW events.
We want to make it clear that we have an error, that it was
reported by firmware and that the RTAS error log will have more
detailed information. eg:

	Ambient temperature too high reported by firmware.
	Check RTAS error log for details

Depending on the error encountered, we now issue an immediate or
an orderly power down.

Move initialization of the EPOW interrupt earlier in boot since we
want to respond to them as early as possible.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-03-28 11:31:59 +11:00
Anton Blanchard f0e939ae37 powerpc/pseries: Print corrupt r3 in FWNMI code
I have a report of an FWNMI with an r3 value that we think is
corrupt, but since we don't print r3 we have no idea what was
wrong with it.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-05-19 14:30:43 +10:00
Grant Likely 476eb49126 powerpc/irq: Stop exporting irq_map
First step in eliminating irq_map[] table entirely

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-05-04 15:02:15 +10:00
Anton Blanchard d368514c30 powerpc: Fix corruption when grabbing FWNMI data
The FWNMI code uses a global buffer without any locks to read the RTAS error
information. If two CPUs take a machine check at once then we will corrupt
this buffer.

Since most FWNMI rtas messages are not of the extended type, we can create a
64bit percpu buffer and use it where possible. If we do receive an extended
RTAS log then we fall back to the old behaviour of using the global buffer.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-01-21 14:08:38 +11:00
Anton Blanchard d47d1d8af5 powerpc: Rework pseries machine check handler
Rework pseries machine check handler:

- If MSR_RI isn't set, we cannot recover even if the machine check was fully
  recovered

- Rename nonfatal to recovered

- Handle RTAS_DISP_LIMITED_RECOVERY

- Use BUS_MCEERR_AR instead of BUS_ADRERR

- Don't check all the RTAS error log fields when receiving a synchronous
  machine check. Recent versions of the pseries firmware do not fill them
  in during a machine check and instead send a follow up error log with
  the detailed information. If we see a synchronous machine check, and we
  came from userspace then kill the task.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-01-21 14:08:38 +11:00
Anton Blanchard 3f9793e6b6 powerpc: Never halt RTAS error logging after receiving an unrecoverable machine check
Newer versions of the System p firwmare send a partial RTAS error log in the
machine check handler with a more detailed response appearing sometime later
via check event.

This means at machine check time we do not have enough information to
ascertain exactly what went on. Furthermore, I have found the RTAS error
logs in the machine check handler contain no useful information, so halting on
them makes little sense. If we want to halt it would make more sense to do
it following the error log received sometime later via check event.

In light of this, never halt the error log in the pseries machine
check handler.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-01-21 14:08:37 +11:00
Mark Nelson b08e281b5a powerpc/pseries: Rename RAS_VECTOR_OFFSET to RTAS_VECTOR_EXTERNAL_INTERRUPT and move to rtas.h
The RAS code has a #define, RAS_VECTOR_OFFSET, that's used in the
check-exception RTAS call for the vector offset of the exception.

We'll be using this same vector offset for the upcoming IO Event interrupts
code (0x500) so let's move it to include/asm/rtas.h and call it
RTAS_VECTOR_EXTERNAL_INTERRUPT.

Signed-off-by: Mark Nelson <markn@au1.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-07-09 11:28:31 +10:00
Mark Nelson 32c96f7765 powerpc/pseries: Make request_ras_irqs() available to other pseries code
At the moment only the RAS code uses event-sources interrupts (for EPOW
events and internal errors) so request_ras_irqs() (which actually requests
the event-sources interrupts) is found in ras.c and is static.

We want to be able to use event-sources interrupts in other pseries code,
so let's rename request_ras_irqs() to request_event_sources_irqs() and
move it to event_sources.c.

This will be used in an upcoming patch that adds support for IO Event
interrupts that come through as event sources.

Signed-off-by: Mark Nelson <markn@au1.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-05-21 17:31:12 +10:00
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00
Michael Ellerman 541b2755c2 [POWERPC] Fix sparse warnings in arch/powerpc/platforms/pseries
Don't return void in pseries/iommu.c
Make mce_data_buf static in pseries/ras.c
Make things static in pseries/rtasd.c
Make things static in pseries/setup.c
vtermno may as well be static in platforms/pseries/lpar.c

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-05-14 22:32:02 +10:00
Michael Ellerman 36f8a2c4c6 [POWERPC] Add CONFIG_PPC_PSERIES_DEBUG to enable debugging for platforms/pseries
Add a DEBUG config setting which turns on all (most) of the debugging
under platforms/pseries.

To have this take effect we need to remove all the #undef DEBUG's, in
various files. We leave the #undef DEBUG in platforms/pseries/lpar.c,
as this enables debugging printks from the low-level hash table routines,
and tends to make your system unusable. If you want those enabled you
still have to turn them on by hand.

Also some of the RAS code has a DEBUG block which causes a functional
change, so I've keyed this off a different (non-existant) debug #define.

This is only enabled if you have PPC_EARLY_DEBUG enabled also.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-04-24 21:08:12 +10:00
Serge E. Hallyn b460cbc581 pid namespaces: define is_global_init() and is_container_init()
is_init() is an ambiguous name for the pid==1 check.  Split it into
is_global_init() and is_container_init().

A cgroup init has it's tsk->pid == 1.

A global init also has it's tsk->pid == 1 and it's active pid namespace
is the init_pid_ns.  But rather than check the active pid namespace,
compare the task structure with 'init_pid_ns.child_reaper', which is
initialized during boot to the /sbin/init process and never changes.

Changelog:

	2.6.22-rc4-mm2-pidns1:
	- Use 'init_pid_ns.child_reaper' to determine if a given task is the
	  global init (/sbin/init) process. This would improve performance
	  and remove dependence on the task_pid().

	2.6.21-mm2-pidns2:

	- [Sukadev Bhattiprolu] Changed is_container_init() calls in {powerpc,
	  ppc,avr32}/traps.c for the _exception() call to is_global_init().
	  This way, we kill only the cgroup if the cgroup's init has a
	  bug rather than force a kernel panic.

[akpm@linux-foundation.org: fix comment]
[sukadev@us.ibm.com: Use is_global_init() in arch/m32r/mm/fault.c]
[bunk@stusta.de: kernel/pid.c: remove unused exports]
[sukadev@us.ibm.com: Fix capability.c to work with threaded init]
Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Acked-by: Pavel Emelianov <xemul@openvz.org>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Herbert Poetzel <herbert@13thfloor.at>
Cc: Kirill Korotaev <dev@sw.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-19 11:53:37 -07:00
Jean Delvare 6473d160b4 PCI: Cleanup the includes of <linux/pci.h>
I noticed that many source files include <linux/pci.h> while they do
not appear to need it. Here is an attempt to clean it all up.

In order to find all possibly affected files, I searched for all
files including <linux/pci.h> but without any other occurence of "pci"
or "PCI". I removed the include statement from all of these, then I
compiled an allmodconfig kernel on both i386 and x86_64 and fixed the
false positives manually.

My tests covered 66% of the affected files, so there could be false
positives remaining. Untested files are:

arch/alpha/kernel/err_common.c
arch/alpha/kernel/err_ev6.c
arch/alpha/kernel/err_ev7.c
arch/ia64/sn/kernel/huberror.c
arch/ia64/sn/kernel/xpnet.c
arch/m68knommu/kernel/dma.c
arch/mips/lib/iomap.c
arch/powerpc/platforms/pseries/ras.c
arch/ppc/8260_io/enet.c
arch/ppc/8260_io/fcc_enet.c
arch/ppc/8xx_io/enet.c
arch/ppc/syslib/ppc4xx_sgdma.c
arch/sh64/mach-cayman/iomap.c
arch/xtensa/kernel/xtensa_ksyms.c
arch/xtensa/platform-iss/setup.c
drivers/i2c/busses/i2c-at91.c
drivers/i2c/busses/i2c-mpc.c
drivers/media/video/saa711x.c
drivers/misc/hdpuftrs/hdpu_cpustate.c
drivers/misc/hdpuftrs/hdpu_nexus.c
drivers/net/au1000_eth.c
drivers/net/fec_8xx/fec_main.c
drivers/net/fec_8xx/fec_mii.c
drivers/net/fs_enet/fs_enet-main.c
drivers/net/fs_enet/mac-fcc.c
drivers/net/fs_enet/mac-fec.c
drivers/net/fs_enet/mac-scc.c
drivers/net/fs_enet/mii-bitbang.c
drivers/net/fs_enet/mii-fec.c
drivers/net/ibm_emac/ibm_emac_core.c
drivers/net/lasi_82596.c
drivers/parisc/hppb.c
drivers/sbus/sbus.c
drivers/video/g364fb.c
drivers/video/platinumfb.c
drivers/video/stifb.c
drivers/video/valkyriefb.c
include/asm-arm/arch-ixp4xx/dma.h
sound/oss/au1550_ac97.c

I would welcome test reports for these files. I am fine with removing
the untested files from the patch if the general opinion is that these
changes aren't safe. The tested part would still be nice to have.

Note that this patch depends on another header fixup patch I submitted
to LKML yesterday:
  [PATCH] scatterlist.h needs types.h
  http://lkml.org/lkml/2007/3/01/141

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-05-02 19:02:35 -07:00
Stephen Rothwell e2eb63927b [POWERPC] Rename get_property to of_get_property: arch/powerpc
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-04-13 03:55:19 +10:00
Michael Ellerman 577830b034 [POWERPC] Consolidate pseries platform header files into pseries.h
Following the example of platforms/pasemi, consolidate a couple of
tiny header files in platforms/pseries into pseries.h.

This gives us a convenient place to put things that need to be
available to the platform code, but not public. And hopefully will
help people resist the temptation of sticking externs in C files.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-02-14 11:50:03 +11:00
David Howells 7d12e780e0 IRQ: Maintain regs pointer globally rather than passing to IRQ handlers
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.

The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around.  On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).

Where appropriate, an arch may override the generic storage facility and do
something different with the variable.  On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.

Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions.  Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller.  A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.

I've build this code with allyesconfig for x86_64 and i386.  I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.

This will affect all archs.  Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:

	struct pt_regs *old_regs = set_irq_regs(regs);

And put the old one back at the end:

	set_irq_regs(old_regs);

Don't pass regs through to generic_handle_irq() or __do_IRQ().

In timer_interrupt(), this sort of change will be necessary:

	-	update_process_times(user_mode(regs));
	-	profile_tick(CPU_PROFILING, regs);
	+	update_process_times(user_mode(get_irq_regs()));
	+	profile_tick(CPU_PROFILING);

I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().

Some notes on the interrupt handling in the drivers:

 (*) input_dev() is now gone entirely.  The regs pointer is no longer stored in
     the input_dev struct.

 (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking.  It does
     something different depending on whether it's been supplied with a regs
     pointer or not.

 (*) Various IRQ handler function pointers have been moved to type
     irq_handler_t.

Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 15:10:12 +01:00
Sukadev Bhattiprolu f400e198b2 [PATCH] pidspace: is_init()
This is an updated version of Eric Biederman's is_init() patch.
(http://lkml.org/lkml/2006/2/6/280).  It applies cleanly to 2.6.18-rc3 and
replaces a few more instances of ->pid == 1 with is_init().

Further, is_init() checks pid and thus removes dependency on Eric's other
patches for now.

Eric's original description:

	There are a lot of places in the kernel where we test for init
	because we give it special properties.  Most  significantly init
	must not die.  This results in code all over the kernel test
	->pid == 1.

	Introduce is_init to capture this case.

	With multiple pid spaces for all of the cases affected we are
	looking for only the first process on the system, not some other
	process that has pid == 1.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Serge Hallyn <serue@us.ibm.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Cc: <lxc-devel@lists.sourceforge.net>
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-29 09:18:12 -07:00