linux-stable.git/arch/powerpc/sysdev/xive/common.c, branch linux-5.17.y Linux kernel stable tree powerpc/xive: Export XIVE IPI information for online-only processors. 2022-04-13T17:27:10+00:00 Sachin Sant sachinp@linux.ibm.com 2022-01-06T11:03:53+00:00 d9bef639de4ff30925c94e807bedc445016d978b [ Upstream commit 279d1a72c0f8021520f68ddb0a1346ff9ba1ea8c ] Cédric pointed out that XIVE IPI information exported via sysfs (debug/powerpc/xive) display empty lines for processors which are not online. Switch to using for_each_online_cpu() so that information is displayed for online-only processors. Reported-by: Cédric Le Goater <clg@kaod.org> Signed-off-by: Sachin Sant <sachinp@linux.ibm.com> Reviewed-by: Cédric Le Goater <clg@kaod.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/164146703333.19039.10920919226094771665.sendpatchset@MacBook-Pro.local Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 279d1a72c0f8021520f68ddb0a1346ff9ba1ea8c ]

Cédric pointed out that XIVE IPI information exported via sysfs
(debug/powerpc/xive) display empty lines for processors which are
not online.

Switch to using for_each_online_cpu() so that information is
displayed for online-only processors.

Reported-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Sachin Sant <sachinp@linux.ibm.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/164146703333.19039.10920919226094771665.sendpatchset@MacBook-Pro.local
Signed-off-by: Sasha Levin <sashal@kernel.org>
powerpc/xive: fix return value of __setup handler 2022-04-08T11:58:19+00:00 Randy Dunlap rdunlap@infradead.org 2022-03-13T06:59:36+00:00 574b6e8f60b47a4955c0c815041b9e1e2806b71b [ Upstream commit d64e3eab75a8e1e900c0fda2410a2df8893d8f85 ] __setup() handlers should return 1 to obsolete_checksetup() in init/main.c to indicate that the boot option has been handled. A return of 0 causes the boot option/value to be listed as an Unknown kernel parameter and added to init's (limited) argument or environment strings. Also, error return codes don't mean anything to obsolete_checksetup() -- only non-zero (usually 1) or zero. So return 1 from xive_off() and xive_store_eoi_cmdline(). Fixes: 243e25112d06 ("powerpc/xive: Native exploitation of the XIVE interrupt controller") Fixes: c21ee04f11ae ("powerpc/xive: Add a kernel parameter for StoreEOI") [lore.kernel.org/r/64644a2f-4a20-bab3-1e15-3b2cdd0defe3@omprussia.ru] Reported-by: Igor Zhbanov <i.zhbanov@omprussia.ru>: Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Reviewed-by: Cédric Le Goater <clg@kaod.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20220313065936.4363-1-rdunlap@infradead.org Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit d64e3eab75a8e1e900c0fda2410a2df8893d8f85 ]

__setup() handlers should return 1 to obsolete_checksetup() in
init/main.c to indicate that the boot option has been handled.

A return of 0 causes the boot option/value to be listed as an Unknown
kernel parameter and added to init's (limited) argument or environment
strings.

Also, error return codes don't mean anything to obsolete_checksetup() --
only non-zero (usually 1) or zero. So return 1 from xive_off() and
xive_store_eoi_cmdline().

Fixes: 243e25112d06 ("powerpc/xive: Native exploitation of the XIVE interrupt controller")
Fixes: c21ee04f11ae ("powerpc/xive: Add a kernel parameter for StoreEOI")
[lore.kernel.org/r/64644a2f-4a20-bab3-1e15-3b2cdd0defe3@omprussia.ru]
Reported-by: Igor Zhbanov <i.zhbanov@omprussia.ru>:
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220313065936.4363-1-rdunlap@infradead.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
powerpc/xive: Fix compile when !CONFIG_PPC_POWERNV. 2021-12-01T23:40:38+00:00 Cédric Le Goater clg@kaod.org 2021-12-01T16:54:18+00:00 2a2ac8a7018b953cd23d770ebd28f8e1ea365df4 The automatic "save & restore" of interrupt context is a POWER10/XIVE2 feature exploited by KVM under the PowerNV platform. It is not available under pSeries and the associated toggle should not be exposed under the XIVE debugfs directory. Introduce a platform handler for debugfs initialization and move the 'save-restore' entry under the native (PowerNV) backend to fix compile when !CONFIG_PPC_POWERNV. Fixes: 1e7684dc4fc7 ("powerpc/xive: Add a debugfs toggle for save-restore") Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Cédric Le Goater <clg@kaod.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211201165418.1041842-1-clg@kaod.org 
The automatic "save & restore" of interrupt context is a POWER10/XIVE2
feature exploited by KVM under the PowerNV platform. It is not
available under pSeries and the associated toggle should not be
exposed under the XIVE debugfs directory.

Introduce a platform handler for debugfs initialization and move the
'save-restore' entry under the native (PowerNV) backend to fix compile
when !CONFIG_PPC_POWERNV.

Fixes: 1e7684dc4fc7 ("powerpc/xive: Add a debugfs toggle for save-restore")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211201165418.1041842-1-clg@kaod.org
powerpc/xive: Add a debugfs toggle for save-restore 2021-11-25T00:25:31+00:00 Cédric Le Goater clg@kaod.org 2021-11-05T10:26:35+00:00 1e7684dc4fc70271c8bf86d397bd4fbfb3581e65 On POWER10, the automatic "save & restore" of interrupt context is always available. Provide a way to deactivate it for tests or performance. Signed-off-by: Cédric Le Goater <clg@kaod.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211105102636.1016378-11-clg@kaod.org 
On POWER10, the automatic "save & restore" of interrupt context is
always available. Provide a way to deactivate it for tests or
performance.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211105102636.1016378-11-clg@kaod.org
powerpc/xive: Add a kernel parameter for StoreEOI 2021-11-25T00:25:30+00:00 Cédric Le Goater clg@kaod.org 2021-11-05T10:26:34+00:00 c21ee04f11ae068aa132cce56d09f618d4a66259 StoreEOI is activated by default on platforms supporting the feature (POWER10) and will be used as soon as firmware advertises its availability. The kernel parameter provides a way to deactivate its use. It can be still be reactivated through debugfs. Signed-off-by: Cédric Le Goater <clg@kaod.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211105102636.1016378-10-clg@kaod.org 
StoreEOI is activated by default on platforms supporting the feature
(POWER10) and will be used as soon as firmware advertises its
availability. The kernel parameter provides a way to deactivate its
use. It can be still be reactivated through debugfs.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211105102636.1016378-10-clg@kaod.org
powerpc/xive: Add a debugfs toggle for StoreEOI 2021-11-25T00:25:30+00:00 Cédric Le Goater clg@kaod.org 2021-11-05T10:26:33+00:00 d7bc1e376cb786e9e8483455584d89cad4b5808f It can be used to deactivate temporarily StoreEOI for tests or performance on platforms supporting the feature (POWER10) Signed-off-by: Cédric Le Goater <clg@kaod.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211105102636.1016378-9-clg@kaod.org 
It can be used to deactivate temporarily StoreEOI for tests or
performance on platforms supporting the feature (POWER10)

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211105102636.1016378-9-clg@kaod.org
powerpc/xive: Add a debugfs file to dump EQs 2021-11-25T00:25:30+00:00 Cédric Le Goater clg@kaod.org 2021-11-05T10:26:32+00:00 08f3f610214f395561bbda03344e641579f6e917 The XIVE driver under Linux uses a single interrupt priority and only one event queue is configured per CPU. Expose the contents under a 'xive/eqs/cpuX' debugfs file. Signed-off-by: Cédric Le Goater <clg@kaod.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211105102636.1016378-8-clg@kaod.org 
The XIVE driver under Linux uses a single interrupt priority and only
one event queue is configured per CPU. Expose the contents under
a 'xive/eqs/cpuX' debugfs file.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211105102636.1016378-8-clg@kaod.org
powerpc/xive: Rename the 'cpus' debugfs file to 'ipis' 2021-11-25T00:25:30+00:00 Cédric Le Goater clg@kaod.org 2021-11-05T10:26:31+00:00 33e1d4a152ce55272b54a16884461218d12d4f1b and remove the EQ entries output which is not very useful since only the next two events of the queue are taken into account. We will improve the dump of the EQ in the next patches. Signed-off-by: Cédric Le Goater <clg@kaod.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211105102636.1016378-7-clg@kaod.org 
and remove the EQ entries output which is not very useful since only
the next two events of the queue are taken into account. We will
improve the dump of the EQ in the next patches.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211105102636.1016378-7-clg@kaod.org
powerpc/xive: Change the debugfs file 'xive' into a directory 2021-11-25T00:25:30+00:00 Cédric Le Goater clg@kaod.org 2021-11-05T10:26:30+00:00 baed14de78b5ee3ca04eae43c5b16e3eeb6e33a8 Use a 'cpus' file to dump CPU states and 'interrupts' to dump IRQ states. Signed-off-by: Cédric Le Goater <clg@kaod.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211105102636.1016378-6-clg@kaod.org 
Use a 'cpus' file to dump CPU states and 'interrupts' to dump IRQ states.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211105102636.1016378-6-clg@kaod.org
powerpc/xive: Introduce xive_core_debugfs_create() 2021-11-25T00:25:30+00:00 Cédric Le Goater clg@kaod.org 2021-11-05T10:26:29+00:00 412877dfae3dc12733bc711ccbd3d02338803865 and fix some compile issues when !CONFIG_DEBUG_FS. Signed-off-by: Cédric Le Goater <clg@kaod.org> [mpe: Add empty stub to fix !CONFIG_DEBUG_FS build] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211105102636.1016378-5-clg@kaod.org 
and fix some compile issues when !CONFIG_DEBUG_FS.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
[mpe: Add empty stub to fix !CONFIG_DEBUG_FS build]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211105102636.1016378-5-clg@kaod.org