powerpc/pseries: Use correct data types from pseries_hp_errorlog struct

_be32 type is defined for some elements in pseries_hp_errorlog
struct but also used them u32 after be32_to_cpu() conversion.

powerpc/pseries: Use correct data types from pseries_hp_errorlog struct

_be32 type is defined for some elements in pseries_hp_errorlog
struct but also used them u32 after be32_to_cpu() conversion.

Example: In handle_dlpar_errorlog()
hp_elog->_drc_u.drc_index = be32_to_cpu(hp_elog->_drc_u.drc_index);

And later assigned to u32 type
dlpar_cpu() - u32 drc_index = hp_elog->_drc_u.drc_index;

This incorrect usage is giving the following warnings and the
patch resolve these warnings with the correct assignment.

arch/powerpc/platforms/pseries/dlpar.c:398:53: sparse: sparse:
incorrect type in argument 1 (different base types) @@
expected unsigned int [usertype] drc_index @@
got restricted __be32 [usertype] drc_index @@
...
arch/powerpc/platforms/pseries/dlpar.c:418:43: sparse: sparse:
incorrect type in assignment (different base types) @@
expected restricted __be32 [usertype] drc_count @@
got unsigned int [usertype] @@

Reported-by: kernel test robot <[email protected]>
Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/
Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/
Signed-off-by: Haren Myneni <[email protected]>

v3:
- Fix warnings from using incorrect data types in pseries_hp_errorlog
struct
v2:
- Remove pr_info() and TODO comments
- Update more information in the commit logs

Signed-off-by: Michael Ellerman <[email protected]>
Link: https://msgid.link/[email protected]

show more ...

powerpc/pseries/memhp: Log more error conditions in add path

When an add operation for multiple LMBs fails, there is currently
little indication from the kernel of what went wrong. Be a little more

powerpc/pseries/memhp: Log more error conditions in add path

When an add operation for multiple LMBs fails, there is currently
little indication from the kernel of what went wrong. Be a little more
verbose about error conditions in the add paths.

Signed-off-by: Nathan Lynch <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://msgid.link/[email protected]

show more ...

powerpc/pseries/memhp: Fix access beyond end of drmem array

dlpar_memory_remove_by_index() may access beyond the bounds of the
drmem lmb array when the LMB lookup fails to match an entry with the
gi

powerpc/pseries/memhp: Fix access beyond end of drmem array

dlpar_memory_remove_by_index() may access beyond the bounds of the
drmem lmb array when the LMB lookup fails to match an entry with the
given DRC index. When the search fails, the cursor is left pointing to
&drmem_info->lmbs[drmem_info->n_lmbs], which is one element past the
last valid entry in the array. The debug message at the end of the
function then dereferences this pointer:

pr_debug("Failed to hot-remove memory at %llx\n",
lmb->base_addr);

This was found by inspection and confirmed with KASAN:

pseries-hotplug-mem: Attempting to hot-remove LMB, drc index 1234
==================================================================
BUG: KASAN: slab-out-of-bounds in dlpar_memory+0x298/0x1658
Read of size 8 at addr c000000364e97fd0 by task bash/949

dump_stack_lvl+0xa4/0xfc (unreliable)
print_report+0x214/0x63c
kasan_report+0x140/0x2e0
__asan_load8+0xa8/0xe0
dlpar_memory+0x298/0x1658
handle_dlpar_errorlog+0x130/0x1d0
dlpar_store+0x18c/0x3e0
kobj_attr_store+0x68/0xa0
sysfs_kf_write+0xc4/0x110
kernfs_fop_write_iter+0x26c/0x390
vfs_write+0x2d4/0x4e0
ksys_write+0xac/0x1a0
system_call_exception+0x268/0x530
system_call_vectored_common+0x15c/0x2ec

Allocated by task 1:
kasan_save_stack+0x48/0x80
kasan_set_track+0x34/0x50
kasan_save_alloc_info+0x34/0x50
__kasan_kmalloc+0xd0/0x120
__kmalloc+0x8c/0x320
kmalloc_array.constprop.0+0x48/0x5c
drmem_init+0x2a0/0x41c
do_one_initcall+0xe0/0x5c0
kernel_init_freeable+0x4ec/0x5a0
kernel_init+0x30/0x1e0
ret_from_kernel_user_thread+0x14/0x1c

The buggy address belongs to the object at c000000364e80000
which belongs to the cache kmalloc-128k of size 131072
The buggy address is located 0 bytes to the right of
allocated 98256-byte region [c000000364e80000, c000000364e97fd0)

==================================================================
pseries-hotplug-mem: Failed to hot-remove memory at 0

Log failed lookups with a separate message and dereference the
cursor only when it points to a valid entry.

Signed-off-by: Nathan Lynch <[email protected]>
Fixes: 51925fb3c5c9 ("powerpc/pseries: Implement memory hotplug remove in the kernel")
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://msgid.link/[email protected]

show more ...

powerpc: Annotate endianness of various variables and functions

Sparse reports several endianness warnings on variables and functions
that are consistently treated as big endian. There are no
multi-

powerpc: Annotate endianness of various variables and functions

Sparse reports several endianness warnings on variables and functions
that are consistently treated as big endian. There are no
multi-endianness shenanigans going on here so fix these low hanging
fruit up in one patch.

All changes are just type annotations; no endianness switching
operations are introduced by this patch.

Signed-off-by: Benjamin Gray <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://msgid.link/[email protected]

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powerpc/book3s64/memhotplug: enable memmap on memory for radix

Radix vmemmap mapping can map things correctly at the PMD level or PTE
level based on different device boundary checks. Hence we skip

powerpc/book3s64/memhotplug: enable memmap on memory for radix

Radix vmemmap mapping can map things correctly at the PMD level or PTE
level based on different device boundary checks. Hence we skip the
restrictions w.r.t vmemmap size to be multiple of PMD_SIZE. This also
makes the feature widely useful because to use PMD_SIZE vmemmap area we
require a memory block size of 2GiB

We can also use MHP_RESERVE_PAGES_MEMMAP_ON_MEMORY to that the feature can
work with a memory block size of 256MB. Using altmap.reserve feature to
align things correctly at pageblock granularity. We can end up losing
some pages in memory with this. For ex: with a 256MiB memory block size,
we require 4 pages to map vmemmap pages, In order to align things
correctly we end up adding a reserve of 28 pages. ie, for every 4096
pages 28 pages get reserved.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Aneesh Kumar K.V <[email protected]>
Reviewed-by: David Hildenbrand <[email protected]>
Cc: Christophe Leroy <[email protected]>
Cc: Michael Ellerman <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Nicholas Piggin <[email protected]>
Cc: Oscar Salvador <[email protected]>
Cc: Vishal Verma <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

show more ...

powerpc/mm: Cleanup memory block size probing

Parse the device tree in early init to find the memory block size to be
used by the kernel. Consolidate the memory block size device tree parsing
to one

powerpc/mm: Cleanup memory block size probing

Parse the device tree in early init to find the memory block size to be
used by the kernel. Consolidate the memory block size device tree parsing
to one helper and use that on both powernv and pseries. We still want to
use machine-specific callback because on all machine types other than
powernv and pseries we continue to return MIN_MEMORY_BLOCK_SIZE.

pseries_memory_block_size used to look for the second memory
block (memory@x) to determine the memory_block_size value. This patch
changed that to look at all memory blocks and make sure we can map them all
correctly using the computed memory block size value.

Add workaround to force 256MB memory block size if device driver managed
memory such as GPU memory is present. This helps to add GPU memory
that is not aligned to 1G.

Co-developed-by: Reza Arbab <[email protected]>
Signed-off-by: Reza Arbab <[email protected]>
Signed-off-by: "Aneesh Kumar K.V" <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://msgid.link/[email protected]

show more ...

powerpc: Use of_address_to_resource()

Replace open coded reading of "reg" or of_get_address()/
of_translate_address() calls with a single call to
of_address_to_resource().

Signed-off-by: Rob Herrin

powerpc: Use of_address_to_resource()

Replace open coded reading of "reg" or of_get_address()/
of_translate_address() calls with a single call to
of_address_to_resource().

Signed-off-by: Rob Herring <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://msgid.link/[email protected]

show more ...

powerpc: Remove asm/prom.h from all files that don't need it

Several files include asm/prom.h for no reason.

Clean it up.

Signed-off-by: Christophe Leroy <[email protected]>
[mpe: Drop c

powerpc: Remove asm/prom.h from all files that don't need it

Several files include asm/prom.h for no reason.

Clean it up.

Signed-off-by: Christophe Leroy <[email protected]>
[mpe: Drop change to prom_parse.c as reported by [email protected]]
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/7c9b8fda63dcf63e1b28f43e7ebdb95182cbc286.1646767214.git.christophe.leroy@csgroup.eu

show more ...

mm/memory_hotplug: remove nid parameter from remove_memory() and friends

There is only a single user remaining. We can simply lookup the nid only
used for node offlining purposes when walking our m

mm/memory_hotplug: remove nid parameter from remove_memory() and friends

There is only a single user remaining. We can simply lookup the nid only
used for node offlining purposes when walking our memory blocks. We don't
expect to remove multi-nid ranges; and if we'd ever do, we most probably
don't care about removing multi-nid ranges that actually result in empty
nodes.

If ever required, we can detect the "multi-nid" scenario and simply try
offlining all online nodes.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: David Hildenbrand <[email protected]>
Acked-by: Michael Ellerman <[email protected]> (powerpc)
Cc: Michael Ellerman <[email protected]>
Cc: Benjamin Herrenschmidt <[email protected]>
Cc: Paul Mackerras <[email protected]>
Cc: "Rafael J. Wysocki" <[email protected]>
Cc: Len Brown <[email protected]>
Cc: Dan Williams <[email protected]>
Cc: Vishal Verma <[email protected]>
Cc: Dave Jiang <[email protected]>
Cc: "Michael S. Tsirkin" <[email protected]>
Cc: Jason Wang <[email protected]>
Cc: Nathan Lynch <[email protected]>
Cc: Laurent Dufour <[email protected]>
Cc: "Aneesh Kumar K.V" <[email protected]>
Cc: Scott Cheloha <[email protected]>
Cc: Anton Blanchard <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Anshuman Khandual <[email protected]>
Cc: Ard Biesheuvel <[email protected]>
Cc: Baoquan He <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Catalin Marinas <[email protected]>
Cc: Christian Borntraeger <[email protected]>
Cc: Christophe Leroy <[email protected]>
Cc: Dave Hansen <[email protected]>
Cc: Heiko Carstens <[email protected]>
Cc: "H. Peter Anvin" <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jia He <[email protected]>
Cc: Joe Perches <[email protected]>
Cc: Kefeng Wang <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Michel Lespinasse <[email protected]>
Cc: Mike Rapoport <[email protected]>
Cc: Nicholas Piggin <[email protected]>
Cc: Oscar Salvador <[email protected]>
Cc: Pankaj Gupta <[email protected]>
Cc: Pankaj Gupta <[email protected]>
Cc: Pavel Tatashin <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Pierre Morel <[email protected]>
Cc: "Rafael J. Wysocki" <[email protected]>
Cc: Rich Felker <[email protected]>
Cc: Sergei Trofimovich <[email protected]>
Cc: Thiago Jung Bauermann <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Vasily Gorbik <[email protected]>
Cc: Vitaly Kuznetsov <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Cc: Wei Yang <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: Yoshinori Sato <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

mm: sparse: pass section_nr to find_memory_block

With CONFIG_SPARSEMEM_EXTREME enabled, __section_nr() which converts
mem_section to section_nr could be costly since it iterates all section
roots to

mm: sparse: pass section_nr to find_memory_block

With CONFIG_SPARSEMEM_EXTREME enabled, __section_nr() which converts
mem_section to section_nr could be costly since it iterates all section
roots to check if the given mem_section is in its range.

On the other hand, __nr_to_section() which converts section_nr to
mem_section can be done in O(1).

Let's pass section_nr instead of mem_section ptr to find_memory_block() in
order to reduce needless iterations.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Ohhoon Kwon <[email protected]>
Acked-by: Michal Hocko <[email protected]>
Acked-by: Mike Rapoport <[email protected]>
Reviewed-by: David Hildenbrand <[email protected]>
Cc: Baoquan He <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

powerpc/pseries: Consolidate different NUMA distance update code paths

The associativity details of the newly added resourced are collected from
the hypervisor via "ibm,configure-connector" rtas cal

powerpc/pseries: Consolidate different NUMA distance update code paths

The associativity details of the newly added resourced are collected from
the hypervisor via "ibm,configure-connector" rtas call. Update the numa
distance details of the newly added numa node after the above call.

Instead of updating NUMA distance every time we lookup a node id
from the associativity property, add helpers that can be used
during boot which does this only once. Also remove the distance
update from node id lookup helpers.

Currently, we duplicate parsing code for ibm,associativity and
ibm,associativity-lookup-arrays in the kernel. The associativity array provided
by these device tree properties are very similar and hence can use
a helper to parse the node id and numa distance details.

Signed-off-by: Aneesh Kumar K.V <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

show more ...

pseries/drmem: update LMBs after LPM

After a LPM, the device tree node ibm,dynamic-reconfiguration-memory may be
updated by the hypervisor in the case the NUMA topology of the LPAR's
memory is updat

pseries/drmem: update LMBs after LPM

After a LPM, the device tree node ibm,dynamic-reconfiguration-memory may be
updated by the hypervisor in the case the NUMA topology of the LPAR's
memory is updated.

This is handled by the kernel, but the memory's node is not updated because
there is no way to move a memory block between nodes from the Linux kernel
point of view.

If later a memory block is added or removed, drmem_update_dt() is called
and it is overwriting the DT node ibm,dynamic-reconfiguration-memory to
match the added or removed LMB. But the LMB's associativity node has not
been updated after the DT node update and thus the node is overwritten by
the Linux's topology instead of the hypervisor one.

Introduce a hook called when the ibm,dynamic-reconfiguration-memory node is
updated to force an update of the LMB's associativity. However, ignore the
call to that hook when the update has been triggered by drmem_update_dt().
Because, in that case, the LMB tree has been used to set the DT property
and thus it doesn't need to be updated back. Since drmem_update_dt() is
called under the protection of the device_hotplug_lock and the hook is
called in the same context, use a simple boolean variable to detect that
call.

Signed-off-by: Laurent Dufour <[email protected]>
Reviewed-by: Nathan Lynch <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

show more ...

powerpc/pseries: fail quicker in dlpar_memory_add_by_ic()

The validation done at the start of dlpar_memory_add_by_ic() is an all
of nothing scenario - if any LMBs in the range is marked as RESERVED

powerpc/pseries: fail quicker in dlpar_memory_add_by_ic()

The validation done at the start of dlpar_memory_add_by_ic() is an all
of nothing scenario - if any LMBs in the range is marked as RESERVED we
can fail right away.

We then can remove the 'lmbs_available' var and its check with
'lmbs_to_add' since the whole LMB range was already validated in the
previous step.

Signed-off-by: Daniel Henrique Barboza <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

show more ...

powerpc/pseries: break early in dlpar_memory_add_by_count() loops

After a successful dlpar_add_lmb() call the LMB is marked as reserved.
Later on, depending whether we added enough LMBs or not, we r

powerpc/pseries: break early in dlpar_memory_add_by_count() loops

After a successful dlpar_add_lmb() call the LMB is marked as reserved.
Later on, depending whether we added enough LMBs or not, we rely on
the marked LMBs to see which ones might need to be removed, and we
remove the reservation of all of them.

These are done in for_each_drmem_lmb() loops without any break
condition. This means that we're going to check all LMBs of the partition
even after going through all the reserved ones.

This patch adds break conditions in both loops to avoid this. The
'lmbs_added' variable was renamed to 'lmbs_reserved', and it's now
being decremented each time a lmb reservation is removed, indicating
if there are still marked LMBs to be processed.

Signed-off-by: Daniel Henrique Barboza <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

show more ...

powerpc/pseries: skip reserved LMBs in dlpar_memory_add_by_count()

The function is counting reserved LMBs as available to be added, but
they aren't. This will cause the function to miscalculate the

powerpc/pseries: skip reserved LMBs in dlpar_memory_add_by_count()

The function is counting reserved LMBs as available to be added, but
they aren't. This will cause the function to miscalculate the available
LMBs and can trigger errors later on when executing dlpar_add_lmb().

Signed-off-by: Daniel Henrique Barboza <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

show more ...

powerpc/pseries: minor enhancements in dlpar_memory_remove_by_ic()

We don't need the 'lmbs_available' variable to count the valid LMBs and
to check if we have less than 'lmbs_to_remove'. We must ens

powerpc/pseries: minor enhancements in dlpar_memory_remove_by_ic()

We don't need the 'lmbs_available' variable to count the valid LMBs and
to check if we have less than 'lmbs_to_remove'. We must ensure that the
entire LMB range must be removed, so we can error out immediately if any
LMB in the range is marked as reserved.

Add a couple of comments explaining the reasoning behind the differences
we have in this function in contrast to what it is done in its sister
function, dlpar_memory_remove_by_count().

Signed-off-by: Daniel Henrique Barboza <[email protected]>
Reviewed-by: David Gibson <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

show more ...

powerpc/pseries: break early in dlpar_memory_remove_by_count() loops

After marking the LMBs as reserved depending on dlpar_remove_lmb() rc,
we evaluate whether we need to add the LMBs back or if we

powerpc/pseries: break early in dlpar_memory_remove_by_count() loops

After marking the LMBs as reserved depending on dlpar_remove_lmb() rc,
we evaluate whether we need to add the LMBs back or if we can release
the LMB DRCs. In both cases, a for_each_drmem_lmb() loop without a break
condition is used. This means that we're going to cycle through all LMBs
of the partition even after we're done with what we were going to do.

This patch adds break conditions in both loops to avoid this. The
'lmbs_removed' variable was renamed to 'lmbs_reserved', and it's now
being decremented each time a lmb reservation is removed, indicating
that the operation we're doing (adding back LMBs or releasing DRCs) is
completed.

Signed-off-by: Daniel Henrique Barboza <[email protected]>
Reviewed-by: David Gibson <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

show more ...

powerpc/pseries: check DRCONF_MEM_RESERVED in lmb_is_removable()

DRCONF_MEM_RESERVED is a flag that represents the "Reserved Memory"
status in LOPAR v2.10, section 4.2.8. If a LMB is marked as reser

powerpc/pseries: check DRCONF_MEM_RESERVED in lmb_is_removable()

DRCONF_MEM_RESERVED is a flag that represents the "Reserved Memory"
status in LOPAR v2.10, section 4.2.8. If a LMB is marked as reserved,
quoting LOPAR, "is not to be used or altered by the base OS". This flag
is read only in the kernel, being set by the firmware/hypervisor in the
DT. As an example, QEMU will set this flag in hw/ppc/spapr.c,
spapr_dt_dynamic_memory().

lmb_is_removable() does not check for DRCONF_MEM_RESERVED. This function
is used in dlpar_remove_lmb() as a guard before the removal logic. Since
it is failing to check for !RESERVED, dlpar_remove_lmb() will fail in a
later stage instead of failing in the validation when receiving a
reserved LMB as input.

lmb_is_removable() is also used in dlpar_memory_remove_by_count() to
evaluate if we have enough LMBs to complete the request. The missing
!RESERVED check in this case is causing dlpar_memory_remove_by_count()
to miscalculate the number of elegible LMBs for the removal, and can
make it error out later on instead of failing in the validation with the
'not enough LMBs to satisfy request' message.

Making a DRCONF_MEM_RESERVED check in lmb_is_removable() fixes all these
issues.

Signed-off-by: Daniel Henrique Barboza <[email protected]>
Reviewed-by: David Gibson <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

show more ...

powerpc/pseries: Set UNISOLATE on dlpar_memory_remove_by_ic() error

As previously done in dlpar_cpu_remove() for CPUs, this patch changes
dlpar_memory_remove_by_ic() to unisolate the LMB DRC when th

powerpc/pseries: Set UNISOLATE on dlpar_memory_remove_by_ic() error

As previously done in dlpar_cpu_remove() for CPUs, this patch changes
dlpar_memory_remove_by_ic() to unisolate the LMB DRC when the LMB is
failed to be removed. The hypervisor, seeing a LMB DRC that was supposed
to be removed being unisolated instead, can do error recovery on its
side.

This change is done in dlpar_memory_remove_by_ic() only because, as of
today, only QEMU is using this code path for error recovery (via the
PSERIES_HP_ELOG_ID_DRC_IC event). phyp treats it as a no-op.

Signed-off-by: Daniel Henrique Barboza <[email protected]>
Reviewed-by: David Gibson <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

show more ...

powerpc/pseries/memhotplug: Remove unused inline function dlpar_memory_remove()

dlpar_memory_remove() is never used, so can be removed.

Signed-off-by: YueHaibing <[email protected]>
Reviewed-by

powerpc/pseries/memhotplug: Remove unused inline function dlpar_memory_remove()

dlpar_memory_remove() is never used, so can be removed.

Signed-off-by: YueHaibing <[email protected]>
Reviewed-by: Daniel Henrique Barboza <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

show more ...

powerpc/pseries/memhotplug: Quieten some DLPAR operations

When attempting to remove by index a set of LMBs a lot of messages are
displayed on the console, even when everything goes fine:

pseries-

powerpc/pseries/memhotplug: Quieten some DLPAR operations

When attempting to remove by index a set of LMBs a lot of messages are
displayed on the console, even when everything goes fine:

pseries-hotplug-mem: Attempting to hot-remove LMB, drc index 8000002d
Offlined Pages 4096
pseries-hotplug-mem: Memory at 2d0000000 was hot-removed

The 2 messages prefixed by "pseries-hotplug-mem" are not really
helpful for the end user, they should be debug outputs.

In case of error, because some of the LMB's pages couldn't be
offlined, the following is displayed on the console:

pseries-hotplug-mem: Attempting to hot-remove LMB, drc index 8000003e
pseries-hotplug-mem: Failed to hot-remove memory at 3e0000000
dlpar: Could not handle DLPAR request "memory remove index 0x8000003e"

Again, the 2 messages prefixed by "pseries-hotplug-mem" are useless,
and the generic DLPAR prefixed message should be enough.

These 2 first changes are mainly triggered by the changes introduced
in drmgr:
https://groups.google.com/g/powerpc-utils-devel/c/Y6ef4NB3EzM/m/9cu5JHRxAQAJ

Also, when adding a bunch of LMBs, a message is displayed in the console per LMB
like these ones:
pseries-hotplug-mem: Memory at 7e0000000 (drc index 8000007e) was hot-added
pseries-hotplug-mem: Memory at 7f0000000 (drc index 8000007f) was hot-added
pseries-hotplug-mem: Memory at 800000000 (drc index 80000080) was hot-added
pseries-hotplug-mem: Memory at 810000000 (drc index 80000081) was hot-added

When adding 1TB of memory and LMB size is 256MB, this leads to 4096
messages to be displayed on the console. These messages are not really
helpful for the end user, so moving them to the DEBUG level.

Signed-off-by: Laurent Dufour <[email protected]>
[mpe: Tweak change log wording]
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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mm/memory_hotplug: prepare passing flags to add_memory() and friends

We soon want to pass flags, e.g., to mark added System RAM resources.
mergeable. Prepare for that.

This patch is based on a sim

mm/memory_hotplug: prepare passing flags to add_memory() and friends

We soon want to pass flags, e.g., to mark added System RAM resources.
mergeable. Prepare for that.

This patch is based on a similar patch by Oscar Salvador:

https://lkml.kernel.org/r/[email protected]

Signed-off-by: David Hildenbrand <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Reviewed-by: Juergen Gross <[email protected]> # Xen related part
Reviewed-by: Pankaj Gupta <[email protected]>
Acked-by: Wei Liu <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Dan Williams <[email protected]>
Cc: Jason Gunthorpe <[email protected]>
Cc: Baoquan He <[email protected]>
Cc: Michael Ellerman <[email protected]>
Cc: Benjamin Herrenschmidt <[email protected]>
Cc: Paul Mackerras <[email protected]>
Cc: "Rafael J. Wysocki" <[email protected]>
Cc: Len Brown <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Vishal Verma <[email protected]>
Cc: Dave Jiang <[email protected]>
Cc: "K. Y. Srinivasan" <[email protected]>
Cc: Haiyang Zhang <[email protected]>
Cc: Stephen Hemminger <[email protected]>
Cc: Wei Liu <[email protected]>
Cc: Heiko Carstens <[email protected]>
Cc: Vasily Gorbik <[email protected]>
Cc: Christian Borntraeger <[email protected]>
Cc: David Hildenbrand <[email protected]>
Cc: "Michael S. Tsirkin" <[email protected]>
Cc: Jason Wang <[email protected]>
Cc: Boris Ostrovsky <[email protected]>
Cc: Stefano Stabellini <[email protected]>
Cc: "Oliver O'Halloran" <[email protected]>
Cc: Pingfan Liu <[email protected]>
Cc: Nathan Lynch <[email protected]>
Cc: Libor Pechacek <[email protected]>
Cc: Anton Blanchard <[email protected]>
Cc: Leonardo Bras <[email protected]>
Cc: Ard Biesheuvel <[email protected]>
Cc: Eric Biederman <[email protected]>
Cc: Julien Grall <[email protected]>
Cc: Kees Cook <[email protected]>
Cc: Roger Pau Monné <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Wei Yang <[email protected]>
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Linus Torvalds <[email protected]>

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powerpc/lmb-size: Use addr #size-cells value when fetching lmb-size

Make it consistent with other usages.

Signed-off-by: Aneesh Kumar K.V <[email protected]>
Signed-off-by: Michael Ellerma

powerpc/lmb-size: Use addr #size-cells value when fetching lmb-size

Make it consistent with other usages.

Signed-off-by: Aneesh Kumar K.V <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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powerpc/memhotplug: Make lmb size 64bit

Similar to commit 89c140bbaeee ("pseries: Fix 64 bit logical memory block panic")
make sure different variables tracking lmb_size are updated to be 64 bit.

T

powerpc/memhotplug: Make lmb size 64bit

Similar to commit 89c140bbaeee ("pseries: Fix 64 bit logical memory block panic")
make sure different variables tracking lmb_size are updated to be 64 bit.

This was found by code audit.

Cc: [email protected]
Signed-off-by: Aneesh Kumar K.V <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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pseries/hotplug-memory: hot-add: skip redundant LMB lookup

During memory hot-add, dlpar_add_lmb() calls memory_add_physaddr_to_nid()
to determine which node id (nid) to use when later calling __add_

pseries/hotplug-memory: hot-add: skip redundant LMB lookup

During memory hot-add, dlpar_add_lmb() calls memory_add_physaddr_to_nid()
to determine which node id (nid) to use when later calling __add_memory().

This is wasteful. On pseries, memory_add_physaddr_to_nid() finds an
appropriate nid for a given address by looking up the LMB containing the
address and then passing that LMB to of_drconf_to_nid_single() to get the
nid. In dlpar_add_lmb() we get this address from the LMB itself.

In short, we have a pointer to an LMB and then we are searching for
that LMB *again* in order to find its nid.

If we call of_drconf_to_nid_single() directly from dlpar_add_lmb() we
can skip the redundant lookup. The only error handling we need to
duplicate from memory_add_physaddr_to_nid() is the fallback to the
default nid when drconf_to_nid_single() returns -1 (NUMA_NO_NODE) or
an invalid nid.

Skipping the extra lookup makes hot-add operations faster, especially
on machines with many LMBs.

Consider an LPAR with 126976 LMBs. In one test, hot-adding 126000
LMBs on an upatched kernel took ~3.5 hours while a patched kernel
completed the same operation in ~2 hours:

Unpatched (12450 seconds):
Sep 9 04:06:31 ltc-brazos1 drmgr[810169]: drmgr: -c mem -a -q 126000
Sep 9 04:06:31 ltc-brazos1 kernel: pseries-hotplug-mem: Attempting to hot-add 126000 LMB(s)
[...]
Sep 9 07:34:01 ltc-brazos1 kernel: pseries-hotplug-mem: Memory at 20000000 (drc index 80000002) was hot-added

Patched (7065 seconds):
Sep 8 21:49:57 ltc-brazos1 drmgr[877703]: drmgr: -c mem -a -q 126000
Sep 8 21:49:57 ltc-brazos1 kernel: pseries-hotplug-mem: Attempting to hot-add 126000 LMB(s)
[...]
Sep 8 23:27:42 ltc-brazos1 kernel: pseries-hotplug-mem: Memory at 20000000 (drc index 80000002) was hot-added

It should be noted that the speedup grows more substantial when
hot-adding LMBs at the end of the drconf range. This is because we
are skipping a linear LMB search.

To see the distinction, consider smaller hot-add test on the same
LPAR. A perf-stat run with 10 iterations showed that hot-adding 4096
LMBs completed less than 1 second faster on a patched kernel:

Unpatched:
Performance counter stats for 'drmgr -c mem -a -q 4096' (10 runs):

104,753.42 msec task-clock # 0.992 CPUs utilized ( +- 0.55% )
4,708 context-switches # 0.045 K/sec ( +- 0.69% )
2,444 cpu-migrations # 0.023 K/sec ( +- 1.25% )
394 page-faults # 0.004 K/sec ( +- 0.22% )
445,902,503,057 cycles # 4.257 GHz ( +- 0.55% ) (66.67%)
8,558,376,740 stalled-cycles-frontend # 1.92% frontend cycles idle ( +- 0.88% ) (49.99%)
300,346,181,651 stalled-cycles-backend # 67.36% backend cycles idle ( +- 0.76% ) (50.01%)
258,091,488,691 instructions # 0.58 insn per cycle
# 1.16 stalled cycles per insn ( +- 0.22% ) (66.67%)
70,568,169,256 branches # 673.660 M/sec ( +- 0.17% ) (50.01%)
3,100,725,426 branch-misses # 4.39% of all branches ( +- 0.20% ) (49.99%)

105.583 +- 0.589 seconds time elapsed ( +- 0.56% )

Patched:
Performance counter stats for 'drmgr -c mem -a -q 4096' (10 runs):

104,055.69 msec task-clock # 0.993 CPUs utilized ( +- 0.32% )
4,606 context-switches # 0.044 K/sec ( +- 0.20% )
2,463 cpu-migrations # 0.024 K/sec ( +- 0.93% )
394 page-faults # 0.004 K/sec ( +- 0.25% )
442,951,129,921 cycles # 4.257 GHz ( +- 0.32% ) (66.66%)
8,710,413,329 stalled-cycles-frontend # 1.97% frontend cycles idle ( +- 0.47% ) (50.06%)
299,656,905,836 stalled-cycles-backend # 67.65% backend cycles idle ( +- 0.39% ) (50.02%)
252,731,168,193 instructions # 0.57 insn per cycle
# 1.19 stalled cycles per insn ( +- 0.20% ) (66.66%)
68,902,851,121 branches # 662.173 M/sec ( +- 0.13% ) (49.94%)
3,100,242,882 branch-misses # 4.50% of all branches ( +- 0.15% ) (49.98%)

104.829 +- 0.325 seconds time elapsed ( +- 0.31% )

This is consistent. An add-by-count hot-add operation adds LMBs
greedily, so LMBs near the start of the drconf range are considered
first. On an otherwise idle LPAR with so many LMBs we would expect to
find the LMBs we need near the start of the drconf range, hence the
smaller speedup.

Signed-off-by: Scott Cheloha <[email protected]>
Reviewed-by: Laurent Dufour <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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