qemu/include
Vaibhav Jain 5f7d861e65 spapr: nested: Add support for reporting Hostwide state counter
Add support for reporting Hostwide state counters for nested KVM pseries
guests running with 'cap-nested-papr' on Qemu-TCG acting as
L0-hypervisor. The Hostwide state counters are statistics about state that
L0-hypervisor maintains for the L2-guests and represent the state of all
L2-guests, not just a specific one.

These stats counters are exposed to L1-Hypervisor by the L0-Hypervisor via a
new bit-flag named 'getHostWideState' for the H_GUEST_GET_STATE hcall which
is documented at [1]. Once this flag is set the hcall should populate the
Guest-State-Elements in the requested GSB with the stat counter
values. Currently following five counters are supported:

* l0_guest_heap_size_inuse
* l0_guest_heap_size_max
* l0_guest_pagetable_size_inuse
* l0_guest_pagetable_size_max
* l0_guest_pagetable_reclaimed

At the moment '0' is being reported for all these counters as these
counters doesn't align with how L0-Qemu manages Guest memory.

The patch implements support for these counters by adding new members to
the 'struct SpaprMachineStateNested'. These new members are then plugged
into the existing 'guest_state_element_types[]' with the help of a new
macro 'GSBE_NESTED_MACHINE_DW' together with a new helper
'get_machine_ptr()'. guest_state_request_check() is updated to ensure
correctness of the requested GSB and finally h_guest_getset_state() is
updated to handle the newly introduced flag
'GUEST_STATE_REQUEST_HOST_WIDE'.

This patch is tested with the proposed linux-kernel implementation to
expose these stat-counter as perf-events at [2].

[1]
https://lore.kernel.org/all/20241222140247.174998-2-vaibhav@linux.ibm.com

[2]
https://lore.kernel.org/all/20241222140247.174998-1-vaibhav@linux.ibm.com

Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Reviewed-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Message-ID: <20250221155449.530645-1-vaibhav@linux.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
2025-03-11 22:43:32 +10:00
..
accel cpus: Introduce SysemuCPUOps::has_work() handler 2025-03-09 17:00:47 +01:00
authz Prefer 'on' | 'off' over 'yes' | 'no' for bool options 2021-01-29 17:07:53 +00:00
block Generic CPUs / accelerators patch queue 2025-03-07 07:39:49 +08:00
chardev chardev/char-hub: implement backend chardev aggregator 2025-02-03 13:57:08 +04:00
crypto crypto: Remove qcrypto_tls_session_get_handshake_status 2025-02-14 15:19:03 -03:00
disas disas: Fix build against Capstone v6 (again) 2024-11-05 10:09:59 +00:00
exec migration: ram block cpr blockers 2025-03-10 12:09:24 -03:00
fpu fpu: Move m68k_denormal fmt flag into floatx80_behaviour 2025-02-25 15:32:57 +00:00
gdbstub gdbstub/helpers: Introduce ldtul_$endian_p() helpers 2024-10-15 11:55:09 -03:00
hw spapr: nested: Add support for reporting Hostwide state counter 2025-03-11 22:43:32 +10:00
io io: Add a read flag for relaxed EOF 2025-02-14 15:19:04 -03:00
libdecnumber Replace config-time define HOST_WORDS_BIGENDIAN 2022-04-06 10:50:37 +02:00
migration migration: Add save_live_complete_precopy_thread handler 2025-03-06 06:47:33 +01:00
monitor monitor: Remove obsolete stubs 2024-06-30 19:51:44 +03:00
net net: checksum: Convert data to void * 2024-11-25 13:59:50 +08:00
qapi error: define g_autoptr() cleanup function for the Error type 2025-03-06 06:47:33 +01:00
qemu -----BEGIN PGP SIGNATURE----- 2025-03-11 09:26:40 +08:00
qobject qapi: Move include/qapi/qmp/ to include/qobject/ 2025-02-10 15:33:16 +01:00
qom qom: remove unused field 2025-01-10 23:34:44 +01:00
scsi hw/ufs: Support for UFS logical unit 2023-09-07 14:01:29 -04:00
semihosting semihosting/console: Avoid including 'cpu.h' 2025-01-17 10:44:00 +00:00
standard-headers linux-headers: Update to Linux v6.14-rc3 2025-03-04 15:42:54 +10:00
system system: Open-code qemu_init_arch_modules() using target_name() 2025-03-06 15:46:18 +01:00
tcg tcg: Introduce the 'z' constraint for a hardware zero register 2025-02-18 08:29:03 -08:00
ui ui/input-legacy.c: remove unused legacy qemu_add_kbd_event_handler() function 2024-11-08 11:06:42 +01:00
user user: Extract common MMAP API to 'user/mmap.h' 2025-03-09 14:54:32 +01:00
elf.h util: spelling fixes 2023-08-31 19:47:43 +02:00
glib-compat.h Bump minimum glib version to v2.66 2024-05-14 12:46:24 +02:00
qemu-io.h Include qemu-common.h exactly where needed 2019-06-12 13:20:20 +02:00
qemu-main.h ui & main loop: Redesign of system-specific main thread event handling 2024-12-31 21:21:34 +01:00