* Re: [PATCH v7 3/6] powerpc: pseries/Kconfig: Add qspinlock build config
2016-09-19 9:23 ` Pan Xinhui
@ 2016-09-19 8:40 ` kbuild test robot
-1 siblings, 0 replies; 25+ messages in thread
From: kbuild test robot @ 2016-09-19 8:40 UTC (permalink / raw)
To: Pan Xinhui
Cc: kbuild-all, linux-kernel, linuxppc-dev, benh, paulus, mpe,
peterz, mingo, paulmck, waiman.long, xinhui.pan, virtualization
[-- Attachment #1: Type: text/plain, Size: 5009 bytes --]
Hi Pan,
[auto build test ERROR on powerpc/next]
[also build test ERROR on v4.8-rc7 next-20160916]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
[Suggest to use git(>=2.9.0) format-patch --base=<commit> (or --base=auto for convenience) to record what (public, well-known) commit your patch series was built on]
[Check https://git-scm.com/docs/git-format-patch for more information]
url: https://github.com/0day-ci/linux/commits/Pan-Xinhui/Implement-qspinlock-pv-qspinlock-on-ppc/20160919-133130
base: https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next
config: powerpc-allyesconfig (attached as .config)
compiler: powerpc64-linux-gnu-gcc (Debian 6.1.1-9) 6.1.1 20160705
reproduce:
wget https://git.kernel.org/cgit/linux/kernel/git/wfg/lkp-tests.git/plain/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# save the attached .config to linux build tree
make.cross ARCH=powerpc
All errors (new ones prefixed by >>):
In file included from include/uapi/linux/stddef.h:1:0,
from include/linux/stddef.h:4,
from include/uapi/linux/posix_types.h:4,
from include/uapi/linux/types.h:13,
from include/linux/types.h:5,
from include/linux/smp.h:10,
from kernel/locking/qspinlock.c:25:
In function '__xchg_relaxed',
inlined from 'queued_spin_lock_slowpath' at kernel/locking/qspinlock.c:184:14:
>> include/linux/compiler.h:491:38: error: call to '__compiletime_assert_113' declared with attribute error: Unsupported size for __xchg_local
_compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
^
include/linux/compiler.h:474:4: note: in definition of macro '__compiletime_assert'
prefix ## suffix(); \
^~~~~~
include/linux/compiler.h:491:2: note: in expansion of macro '_compiletime_assert'
_compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
^~~~~~~~~~~~~~~~~~~
include/linux/bug.h:51:37: note: in expansion of macro 'compiletime_assert'
#define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
^~~~~~~~~~~~~~~~~~
arch/powerpc/include/asm/cmpxchg.h:113:2: note: in expansion of macro 'BUILD_BUG_ON_MSG'
BUILD_BUG_ON_MSG(1, "Unsupported size for __xchg_local");
^~~~~~~~~~~~~~~~
vim +/__compiletime_assert_113 +491 include/linux/compiler.h
9a8ab1c3 Daniel Santos 2013-02-21 475 __compiletime_error_fallback(__cond); \
9a8ab1c3 Daniel Santos 2013-02-21 476 } while (0)
9a8ab1c3 Daniel Santos 2013-02-21 477
9a8ab1c3 Daniel Santos 2013-02-21 478 #define _compiletime_assert(condition, msg, prefix, suffix) \
9a8ab1c3 Daniel Santos 2013-02-21 479 __compiletime_assert(condition, msg, prefix, suffix)
9a8ab1c3 Daniel Santos 2013-02-21 480
9a8ab1c3 Daniel Santos 2013-02-21 481 /**
9a8ab1c3 Daniel Santos 2013-02-21 482 * compiletime_assert - break build and emit msg if condition is false
9a8ab1c3 Daniel Santos 2013-02-21 483 * @condition: a compile-time constant condition to check
9a8ab1c3 Daniel Santos 2013-02-21 484 * @msg: a message to emit if condition is false
9a8ab1c3 Daniel Santos 2013-02-21 485 *
9a8ab1c3 Daniel Santos 2013-02-21 486 * In tradition of POSIX assert, this macro will break the build if the
9a8ab1c3 Daniel Santos 2013-02-21 487 * supplied condition is *false*, emitting the supplied error message if the
9a8ab1c3 Daniel Santos 2013-02-21 488 * compiler has support to do so.
9a8ab1c3 Daniel Santos 2013-02-21 489 */
9a8ab1c3 Daniel Santos 2013-02-21 490 #define compiletime_assert(condition, msg) \
9a8ab1c3 Daniel Santos 2013-02-21 @491 _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
9a8ab1c3 Daniel Santos 2013-02-21 492
47933ad4 Peter Zijlstra 2013-11-06 493 #define compiletime_assert_atomic_type(t) \
47933ad4 Peter Zijlstra 2013-11-06 494 compiletime_assert(__native_word(t), \
47933ad4 Peter Zijlstra 2013-11-06 495 "Need native word sized stores/loads for atomicity.")
47933ad4 Peter Zijlstra 2013-11-06 496
9c3cdc1f Linus Torvalds 2008-05-10 497 /*
9c3cdc1f Linus Torvalds 2008-05-10 498 * Prevent the compiler from merging or refetching accesses. The compiler
9c3cdc1f Linus Torvalds 2008-05-10 499 * is also forbidden from reordering successive instances of ACCESS_ONCE(),
:::::: The code at line 491 was first introduced by commit
:::::: 9a8ab1c39970a4938a72d94e6fd13be88a797590 bug.h, compiler.h: introduce compiletime_assert & BUILD_BUG_ON_MSG
:::::: TO: Daniel Santos <daniel.santos@pobox.com>
:::::: CC: Linus Torvalds <torvalds@linux-foundation.org>
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 49942 bytes --]
^ permalink raw reply [flat|nested] 25+ messages in thread
* Re: [PATCH v7 3/6] powerpc: pseries/Kconfig: Add qspinlock build config
@ 2016-09-19 8:40 ` kbuild test robot
0 siblings, 0 replies; 25+ messages in thread
From: kbuild test robot @ 2016-09-19 8:40 UTC (permalink / raw)
Cc: xinhui.pan, peterz, mpe, linux-kernel, waiman.long,
virtualization, mingo, paulus, kbuild-all, benh, paulmck,
linuxppc-dev
[-- Attachment #1: Type: text/plain, Size: 5009 bytes --]
Hi Pan,
[auto build test ERROR on powerpc/next]
[also build test ERROR on v4.8-rc7 next-20160916]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
[Suggest to use git(>=2.9.0) format-patch --base=<commit> (or --base=auto for convenience) to record what (public, well-known) commit your patch series was built on]
[Check https://git-scm.com/docs/git-format-patch for more information]
url: https://github.com/0day-ci/linux/commits/Pan-Xinhui/Implement-qspinlock-pv-qspinlock-on-ppc/20160919-133130
base: https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next
config: powerpc-allyesconfig (attached as .config)
compiler: powerpc64-linux-gnu-gcc (Debian 6.1.1-9) 6.1.1 20160705
reproduce:
wget https://git.kernel.org/cgit/linux/kernel/git/wfg/lkp-tests.git/plain/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# save the attached .config to linux build tree
make.cross ARCH=powerpc
All errors (new ones prefixed by >>):
In file included from include/uapi/linux/stddef.h:1:0,
from include/linux/stddef.h:4,
from include/uapi/linux/posix_types.h:4,
from include/uapi/linux/types.h:13,
from include/linux/types.h:5,
from include/linux/smp.h:10,
from kernel/locking/qspinlock.c:25:
In function '__xchg_relaxed',
inlined from 'queued_spin_lock_slowpath' at kernel/locking/qspinlock.c:184:14:
>> include/linux/compiler.h:491:38: error: call to '__compiletime_assert_113' declared with attribute error: Unsupported size for __xchg_local
_compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
^
include/linux/compiler.h:474:4: note: in definition of macro '__compiletime_assert'
prefix ## suffix(); \
^~~~~~
include/linux/compiler.h:491:2: note: in expansion of macro '_compiletime_assert'
_compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
^~~~~~~~~~~~~~~~~~~
include/linux/bug.h:51:37: note: in expansion of macro 'compiletime_assert'
#define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
^~~~~~~~~~~~~~~~~~
arch/powerpc/include/asm/cmpxchg.h:113:2: note: in expansion of macro 'BUILD_BUG_ON_MSG'
BUILD_BUG_ON_MSG(1, "Unsupported size for __xchg_local");
^~~~~~~~~~~~~~~~
vim +/__compiletime_assert_113 +491 include/linux/compiler.h
9a8ab1c3 Daniel Santos 2013-02-21 475 __compiletime_error_fallback(__cond); \
9a8ab1c3 Daniel Santos 2013-02-21 476 } while (0)
9a8ab1c3 Daniel Santos 2013-02-21 477
9a8ab1c3 Daniel Santos 2013-02-21 478 #define _compiletime_assert(condition, msg, prefix, suffix) \
9a8ab1c3 Daniel Santos 2013-02-21 479 __compiletime_assert(condition, msg, prefix, suffix)
9a8ab1c3 Daniel Santos 2013-02-21 480
9a8ab1c3 Daniel Santos 2013-02-21 481 /**
9a8ab1c3 Daniel Santos 2013-02-21 482 * compiletime_assert - break build and emit msg if condition is false
9a8ab1c3 Daniel Santos 2013-02-21 483 * @condition: a compile-time constant condition to check
9a8ab1c3 Daniel Santos 2013-02-21 484 * @msg: a message to emit if condition is false
9a8ab1c3 Daniel Santos 2013-02-21 485 *
9a8ab1c3 Daniel Santos 2013-02-21 486 * In tradition of POSIX assert, this macro will break the build if the
9a8ab1c3 Daniel Santos 2013-02-21 487 * supplied condition is *false*, emitting the supplied error message if the
9a8ab1c3 Daniel Santos 2013-02-21 488 * compiler has support to do so.
9a8ab1c3 Daniel Santos 2013-02-21 489 */
9a8ab1c3 Daniel Santos 2013-02-21 490 #define compiletime_assert(condition, msg) \
9a8ab1c3 Daniel Santos 2013-02-21 @491 _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
9a8ab1c3 Daniel Santos 2013-02-21 492
47933ad4 Peter Zijlstra 2013-11-06 493 #define compiletime_assert_atomic_type(t) \
47933ad4 Peter Zijlstra 2013-11-06 494 compiletime_assert(__native_word(t), \
47933ad4 Peter Zijlstra 2013-11-06 495 "Need native word sized stores/loads for atomicity.")
47933ad4 Peter Zijlstra 2013-11-06 496
9c3cdc1f Linus Torvalds 2008-05-10 497 /*
9c3cdc1f Linus Torvalds 2008-05-10 498 * Prevent the compiler from merging or refetching accesses. The compiler
9c3cdc1f Linus Torvalds 2008-05-10 499 * is also forbidden from reordering successive instances of ACCESS_ONCE(),
:::::: The code at line 491 was first introduced by commit
:::::: 9a8ab1c39970a4938a72d94e6fd13be88a797590 bug.h, compiler.h: introduce compiletime_assert & BUILD_BUG_ON_MSG
:::::: TO: Daniel Santos <daniel.santos@pobox.com>
:::::: CC: Linus Torvalds <torvalds@linux-foundation.org>
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 49942 bytes --]
[-- Attachment #3: Type: text/plain, Size: 183 bytes --]
_______________________________________________
Virtualization mailing list
Virtualization@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/virtualization
^ permalink raw reply [flat|nested] 25+ messages in thread
* Re: [PATCH v7 6/6] powerpc: pSeries: Add pv-qspinlock build config/make
2016-09-19 9:23 ` [PATCH v7 6/6] powerpc: pSeries: Add pv-qspinlock build config/make Pan Xinhui
@ 2016-09-19 8:58 ` kbuild test robot
0 siblings, 0 replies; 25+ messages in thread
From: kbuild test robot @ 2016-09-19 8:58 UTC (permalink / raw)
To: Pan Xinhui
Cc: kbuild-all, linux-kernel, linuxppc-dev, benh, paulus, mpe,
peterz, mingo, paulmck, waiman.long, xinhui.pan, virtualization
[-- Attachment #1: Type: text/plain, Size: 10966 bytes --]
Hi Pan,
[auto build test ERROR on powerpc/next]
[also build test ERROR on v4.8-rc7 next-20160916]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
[Suggest to use git(>=2.9.0) format-patch --base=<commit> (or --base=auto for convenience) to record what (public, well-known) commit your patch series was built on]
[Check https://git-scm.com/docs/git-format-patch for more information]
url: https://github.com/0day-ci/linux/commits/Pan-Xinhui/Implement-qspinlock-pv-qspinlock-on-ppc/20160919-133130
base: https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next
config: powerpc-allyesconfig (attached as .config)
compiler: powerpc64-linux-gnu-gcc (Debian 6.1.1-9) 6.1.1 20160705
reproduce:
wget https://git.kernel.org/cgit/linux/kernel/git/wfg/lkp-tests.git/plain/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# save the attached .config to linux build tree
make.cross ARCH=powerpc
All errors (new ones prefixed by >>):
include/linux/compiler.h:491:2: note: in expansion of macro '_compiletime_assert'
_compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
^~~~~~~~~~~~~~~~~~~
include/linux/bug.h:51:37: note: in expansion of macro 'compiletime_assert'
#define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
^~~~~~~~~~~~~~~~~~
arch/powerpc/include/asm/cmpxchg.h:326:2: note: in expansion of macro 'BUILD_BUG_ON_MSG'
BUILD_BUG_ON_MSG(1, "Unsupported size for __cmpxchg");
^~~~~~~~~~~~~~~~
In function '__cmpxchg',
inlined from 'pv_wait_node' at kernel/locking/qspinlock_paravirt.h:328:3,
inlined from '__pv_queued_spin_lock_slowpath' at kernel/locking/qspinlock.c:538:3:
include/linux/compiler.h:491:38: error: call to '__compiletime_assert_326' declared with attribute error: Unsupported size for __cmpxchg
_compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
^
include/linux/compiler.h:474:4: note: in definition of macro '__compiletime_assert'
prefix ## suffix(); \
^~~~~~
include/linux/compiler.h:491:2: note: in expansion of macro '_compiletime_assert'
_compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
^~~~~~~~~~~~~~~~~~~
include/linux/bug.h:51:37: note: in expansion of macro 'compiletime_assert'
#define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
^~~~~~~~~~~~~~~~~~
arch/powerpc/include/asm/cmpxchg.h:326:2: note: in expansion of macro 'BUILD_BUG_ON_MSG'
BUILD_BUG_ON_MSG(1, "Unsupported size for __cmpxchg");
^~~~~~~~~~~~~~~~
In function '__cmpxchg',
inlined from 'pv_wait_head_or_lock' at kernel/locking/qspinlock_paravirt.h:109:10,
inlined from '__pv_queued_spin_lock_slowpath' at kernel/locking/qspinlock.c:573:5:
include/linux/compiler.h:491:38: error: call to '__compiletime_assert_326' declared with attribute error: Unsupported size for __cmpxchg
_compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
^
include/linux/compiler.h:474:4: note: in definition of macro '__compiletime_assert'
prefix ## suffix(); \
^~~~~~
include/linux/compiler.h:491:2: note: in expansion of macro '_compiletime_assert'
_compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
^~~~~~~~~~~~~~~~~~~
include/linux/bug.h:51:37: note: in expansion of macro 'compiletime_assert'
#define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
^~~~~~~~~~~~~~~~~~
arch/powerpc/include/asm/cmpxchg.h:326:2: note: in expansion of macro 'BUILD_BUG_ON_MSG'
BUILD_BUG_ON_MSG(1, "Unsupported size for __cmpxchg");
^~~~~~~~~~~~~~~~
In function '__xchg_relaxed',
inlined from 'pv_wait_head_or_lock' at kernel/locking/qspinlock_paravirt.h:442:8,
inlined from '__pv_queued_spin_lock_slowpath' at kernel/locking/qspinlock.c:573:5:
include/linux/compiler.h:491:38: error: call to '__compiletime_assert_113' declared with attribute error: Unsupported size for __xchg_local
_compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
^
include/linux/compiler.h:474:4: note: in definition of macro '__compiletime_assert'
prefix ## suffix(); \
^~~~~~
include/linux/compiler.h:491:2: note: in expansion of macro '_compiletime_assert'
_compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
^~~~~~~~~~~~~~~~~~~
include/linux/bug.h:51:37: note: in expansion of macro 'compiletime_assert'
#define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
^~~~~~~~~~~~~~~~~~
arch/powerpc/include/asm/cmpxchg.h:113:2: note: in expansion of macro 'BUILD_BUG_ON_MSG'
BUILD_BUG_ON_MSG(1, "Unsupported size for __xchg_local");
^~~~~~~~~~~~~~~~
In function '__cmpxchg',
inlined from 'pv_kick_node' at kernel/locking/qspinlock_paravirt.h:366:6,
inlined from '__pv_queued_spin_lock_slowpath' at kernel/locking/qspinlock.c:616:2:
include/linux/compiler.h:491:38: error: call to '__compiletime_assert_326' declared with attribute error: Unsupported size for __cmpxchg
_compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
^
include/linux/compiler.h:474:4: note: in definition of macro '__compiletime_assert'
prefix ## suffix(); \
^~~~~~
include/linux/compiler.h:491:2: note: in expansion of macro '_compiletime_assert'
_compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
^~~~~~~~~~~~~~~~~~~
include/linux/bug.h:51:37: note: in expansion of macro 'compiletime_assert'
#define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
^~~~~~~~~~~~~~~~~~
arch/powerpc/include/asm/cmpxchg.h:326:2: note: in expansion of macro 'BUILD_BUG_ON_MSG'
BUILD_BUG_ON_MSG(1, "Unsupported size for __cmpxchg");
^~~~~~~~~~~~~~~~
In function '__xchg_relaxed',
inlined from '__pv_queued_spin_lock_slowpath' at kernel/locking/qspinlock.c:184:14:
include/linux/compiler.h:491:38: error: call to '__compiletime_assert_113' declared with attribute error: Unsupported size for __xchg_local
_compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
^
include/linux/compiler.h:474:4: note: in definition of macro '__compiletime_assert'
prefix ## suffix(); \
^~~~~~
include/linux/compiler.h:491:2: note: in expansion of macro '_compiletime_assert'
_compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
^~~~~~~~~~~~~~~~~~~
include/linux/bug.h:51:37: note: in expansion of macro 'compiletime_assert'
#define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
^~~~~~~~~~~~~~~~~~
arch/powerpc/include/asm/cmpxchg.h:113:2: note: in expansion of macro 'BUILD_BUG_ON_MSG'
BUILD_BUG_ON_MSG(1, "Unsupported size for __xchg_local");
^~~~~~~~~~~~~~~~
In function '__cmpxchg_relaxed',
inlined from '__pv_queued_spin_unlock' at kernel/locking/qspinlock_paravirt.h:547:11:
>> include/linux/compiler.h:491:38: error: call to '__compiletime_assert_358' declared with attribute error: Unsupported size for __cmpxchg_relaxed
_compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
^
include/linux/compiler.h:474:4: note: in definition of macro '__compiletime_assert'
prefix ## suffix(); \
^~~~~~
include/linux/compiler.h:491:2: note: in expansion of macro '_compiletime_assert'
_compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
^~~~~~~~~~~~~~~~~~~
include/linux/bug.h:51:37: note: in expansion of macro 'compiletime_assert'
#define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
^~~~~~~~~~~~~~~~~~
arch/powerpc/include/asm/cmpxchg.h:358:2: note: in expansion of macro 'BUILD_BUG_ON_MSG'
BUILD_BUG_ON_MSG(1, "Unsupported size for __cmpxchg_relaxed");
^~~~~~~~~~~~~~~~
vim +/__compiletime_assert_358 +491 include/linux/compiler.h
9a8ab1c3 Daniel Santos 2013-02-21 475 __compiletime_error_fallback(__cond); \
9a8ab1c3 Daniel Santos 2013-02-21 476 } while (0)
9a8ab1c3 Daniel Santos 2013-02-21 477
9a8ab1c3 Daniel Santos 2013-02-21 478 #define _compiletime_assert(condition, msg, prefix, suffix) \
9a8ab1c3 Daniel Santos 2013-02-21 479 __compiletime_assert(condition, msg, prefix, suffix)
9a8ab1c3 Daniel Santos 2013-02-21 480
9a8ab1c3 Daniel Santos 2013-02-21 481 /**
9a8ab1c3 Daniel Santos 2013-02-21 482 * compiletime_assert - break build and emit msg if condition is false
9a8ab1c3 Daniel Santos 2013-02-21 483 * @condition: a compile-time constant condition to check
9a8ab1c3 Daniel Santos 2013-02-21 484 * @msg: a message to emit if condition is false
9a8ab1c3 Daniel Santos 2013-02-21 485 *
9a8ab1c3 Daniel Santos 2013-02-21 486 * In tradition of POSIX assert, this macro will break the build if the
9a8ab1c3 Daniel Santos 2013-02-21 487 * supplied condition is *false*, emitting the supplied error message if the
9a8ab1c3 Daniel Santos 2013-02-21 488 * compiler has support to do so.
9a8ab1c3 Daniel Santos 2013-02-21 489 */
9a8ab1c3 Daniel Santos 2013-02-21 490 #define compiletime_assert(condition, msg) \
9a8ab1c3 Daniel Santos 2013-02-21 @491 _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
9a8ab1c3 Daniel Santos 2013-02-21 492
47933ad4 Peter Zijlstra 2013-11-06 493 #define compiletime_assert_atomic_type(t) \
47933ad4 Peter Zijlstra 2013-11-06 494 compiletime_assert(__native_word(t), \
47933ad4 Peter Zijlstra 2013-11-06 495 "Need native word sized stores/loads for atomicity.")
47933ad4 Peter Zijlstra 2013-11-06 496
9c3cdc1f Linus Torvalds 2008-05-10 497 /*
9c3cdc1f Linus Torvalds 2008-05-10 498 * Prevent the compiler from merging or refetching accesses. The compiler
9c3cdc1f Linus Torvalds 2008-05-10 499 * is also forbidden from reordering successive instances of ACCESS_ONCE(),
:::::: The code at line 491 was first introduced by commit
:::::: 9a8ab1c39970a4938a72d94e6fd13be88a797590 bug.h, compiler.h: introduce compiletime_assert & BUILD_BUG_ON_MSG
:::::: TO: Daniel Santos <daniel.santos@pobox.com>
:::::: CC: Linus Torvalds <torvalds@linux-foundation.org>
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 49942 bytes --]
^ permalink raw reply [flat|nested] 25+ messages in thread
* Re: [PATCH v7 6/6] powerpc: pSeries: Add pv-qspinlock build config/make
@ 2016-09-19 8:58 ` kbuild test robot
0 siblings, 0 replies; 25+ messages in thread
From: kbuild test robot @ 2016-09-19 8:58 UTC (permalink / raw)
Cc: xinhui.pan, peterz, mpe, linux-kernel, waiman.long,
virtualization, mingo, paulus, kbuild-all, benh, paulmck,
linuxppc-dev
[-- Attachment #1: Type: text/plain, Size: 10966 bytes --]
Hi Pan,
[auto build test ERROR on powerpc/next]
[also build test ERROR on v4.8-rc7 next-20160916]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
[Suggest to use git(>=2.9.0) format-patch --base=<commit> (or --base=auto for convenience) to record what (public, well-known) commit your patch series was built on]
[Check https://git-scm.com/docs/git-format-patch for more information]
url: https://github.com/0day-ci/linux/commits/Pan-Xinhui/Implement-qspinlock-pv-qspinlock-on-ppc/20160919-133130
base: https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next
config: powerpc-allyesconfig (attached as .config)
compiler: powerpc64-linux-gnu-gcc (Debian 6.1.1-9) 6.1.1 20160705
reproduce:
wget https://git.kernel.org/cgit/linux/kernel/git/wfg/lkp-tests.git/plain/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# save the attached .config to linux build tree
make.cross ARCH=powerpc
All errors (new ones prefixed by >>):
include/linux/compiler.h:491:2: note: in expansion of macro '_compiletime_assert'
_compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
^~~~~~~~~~~~~~~~~~~
include/linux/bug.h:51:37: note: in expansion of macro 'compiletime_assert'
#define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
^~~~~~~~~~~~~~~~~~
arch/powerpc/include/asm/cmpxchg.h:326:2: note: in expansion of macro 'BUILD_BUG_ON_MSG'
BUILD_BUG_ON_MSG(1, "Unsupported size for __cmpxchg");
^~~~~~~~~~~~~~~~
In function '__cmpxchg',
inlined from 'pv_wait_node' at kernel/locking/qspinlock_paravirt.h:328:3,
inlined from '__pv_queued_spin_lock_slowpath' at kernel/locking/qspinlock.c:538:3:
include/linux/compiler.h:491:38: error: call to '__compiletime_assert_326' declared with attribute error: Unsupported size for __cmpxchg
_compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
^
include/linux/compiler.h:474:4: note: in definition of macro '__compiletime_assert'
prefix ## suffix(); \
^~~~~~
include/linux/compiler.h:491:2: note: in expansion of macro '_compiletime_assert'
_compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
^~~~~~~~~~~~~~~~~~~
include/linux/bug.h:51:37: note: in expansion of macro 'compiletime_assert'
#define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
^~~~~~~~~~~~~~~~~~
arch/powerpc/include/asm/cmpxchg.h:326:2: note: in expansion of macro 'BUILD_BUG_ON_MSG'
BUILD_BUG_ON_MSG(1, "Unsupported size for __cmpxchg");
^~~~~~~~~~~~~~~~
In function '__cmpxchg',
inlined from 'pv_wait_head_or_lock' at kernel/locking/qspinlock_paravirt.h:109:10,
inlined from '__pv_queued_spin_lock_slowpath' at kernel/locking/qspinlock.c:573:5:
include/linux/compiler.h:491:38: error: call to '__compiletime_assert_326' declared with attribute error: Unsupported size for __cmpxchg
_compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
^
include/linux/compiler.h:474:4: note: in definition of macro '__compiletime_assert'
prefix ## suffix(); \
^~~~~~
include/linux/compiler.h:491:2: note: in expansion of macro '_compiletime_assert'
_compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
^~~~~~~~~~~~~~~~~~~
include/linux/bug.h:51:37: note: in expansion of macro 'compiletime_assert'
#define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
^~~~~~~~~~~~~~~~~~
arch/powerpc/include/asm/cmpxchg.h:326:2: note: in expansion of macro 'BUILD_BUG_ON_MSG'
BUILD_BUG_ON_MSG(1, "Unsupported size for __cmpxchg");
^~~~~~~~~~~~~~~~
In function '__xchg_relaxed',
inlined from 'pv_wait_head_or_lock' at kernel/locking/qspinlock_paravirt.h:442:8,
inlined from '__pv_queued_spin_lock_slowpath' at kernel/locking/qspinlock.c:573:5:
include/linux/compiler.h:491:38: error: call to '__compiletime_assert_113' declared with attribute error: Unsupported size for __xchg_local
_compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
^
include/linux/compiler.h:474:4: note: in definition of macro '__compiletime_assert'
prefix ## suffix(); \
^~~~~~
include/linux/compiler.h:491:2: note: in expansion of macro '_compiletime_assert'
_compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
^~~~~~~~~~~~~~~~~~~
include/linux/bug.h:51:37: note: in expansion of macro 'compiletime_assert'
#define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
^~~~~~~~~~~~~~~~~~
arch/powerpc/include/asm/cmpxchg.h:113:2: note: in expansion of macro 'BUILD_BUG_ON_MSG'
BUILD_BUG_ON_MSG(1, "Unsupported size for __xchg_local");
^~~~~~~~~~~~~~~~
In function '__cmpxchg',
inlined from 'pv_kick_node' at kernel/locking/qspinlock_paravirt.h:366:6,
inlined from '__pv_queued_spin_lock_slowpath' at kernel/locking/qspinlock.c:616:2:
include/linux/compiler.h:491:38: error: call to '__compiletime_assert_326' declared with attribute error: Unsupported size for __cmpxchg
_compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
^
include/linux/compiler.h:474:4: note: in definition of macro '__compiletime_assert'
prefix ## suffix(); \
^~~~~~
include/linux/compiler.h:491:2: note: in expansion of macro '_compiletime_assert'
_compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
^~~~~~~~~~~~~~~~~~~
include/linux/bug.h:51:37: note: in expansion of macro 'compiletime_assert'
#define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
^~~~~~~~~~~~~~~~~~
arch/powerpc/include/asm/cmpxchg.h:326:2: note: in expansion of macro 'BUILD_BUG_ON_MSG'
BUILD_BUG_ON_MSG(1, "Unsupported size for __cmpxchg");
^~~~~~~~~~~~~~~~
In function '__xchg_relaxed',
inlined from '__pv_queued_spin_lock_slowpath' at kernel/locking/qspinlock.c:184:14:
include/linux/compiler.h:491:38: error: call to '__compiletime_assert_113' declared with attribute error: Unsupported size for __xchg_local
_compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
^
include/linux/compiler.h:474:4: note: in definition of macro '__compiletime_assert'
prefix ## suffix(); \
^~~~~~
include/linux/compiler.h:491:2: note: in expansion of macro '_compiletime_assert'
_compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
^~~~~~~~~~~~~~~~~~~
include/linux/bug.h:51:37: note: in expansion of macro 'compiletime_assert'
#define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
^~~~~~~~~~~~~~~~~~
arch/powerpc/include/asm/cmpxchg.h:113:2: note: in expansion of macro 'BUILD_BUG_ON_MSG'
BUILD_BUG_ON_MSG(1, "Unsupported size for __xchg_local");
^~~~~~~~~~~~~~~~
In function '__cmpxchg_relaxed',
inlined from '__pv_queued_spin_unlock' at kernel/locking/qspinlock_paravirt.h:547:11:
>> include/linux/compiler.h:491:38: error: call to '__compiletime_assert_358' declared with attribute error: Unsupported size for __cmpxchg_relaxed
_compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
^
include/linux/compiler.h:474:4: note: in definition of macro '__compiletime_assert'
prefix ## suffix(); \
^~~~~~
include/linux/compiler.h:491:2: note: in expansion of macro '_compiletime_assert'
_compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
^~~~~~~~~~~~~~~~~~~
include/linux/bug.h:51:37: note: in expansion of macro 'compiletime_assert'
#define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
^~~~~~~~~~~~~~~~~~
arch/powerpc/include/asm/cmpxchg.h:358:2: note: in expansion of macro 'BUILD_BUG_ON_MSG'
BUILD_BUG_ON_MSG(1, "Unsupported size for __cmpxchg_relaxed");
^~~~~~~~~~~~~~~~
vim +/__compiletime_assert_358 +491 include/linux/compiler.h
9a8ab1c3 Daniel Santos 2013-02-21 475 __compiletime_error_fallback(__cond); \
9a8ab1c3 Daniel Santos 2013-02-21 476 } while (0)
9a8ab1c3 Daniel Santos 2013-02-21 477
9a8ab1c3 Daniel Santos 2013-02-21 478 #define _compiletime_assert(condition, msg, prefix, suffix) \
9a8ab1c3 Daniel Santos 2013-02-21 479 __compiletime_assert(condition, msg, prefix, suffix)
9a8ab1c3 Daniel Santos 2013-02-21 480
9a8ab1c3 Daniel Santos 2013-02-21 481 /**
9a8ab1c3 Daniel Santos 2013-02-21 482 * compiletime_assert - break build and emit msg if condition is false
9a8ab1c3 Daniel Santos 2013-02-21 483 * @condition: a compile-time constant condition to check
9a8ab1c3 Daniel Santos 2013-02-21 484 * @msg: a message to emit if condition is false
9a8ab1c3 Daniel Santos 2013-02-21 485 *
9a8ab1c3 Daniel Santos 2013-02-21 486 * In tradition of POSIX assert, this macro will break the build if the
9a8ab1c3 Daniel Santos 2013-02-21 487 * supplied condition is *false*, emitting the supplied error message if the
9a8ab1c3 Daniel Santos 2013-02-21 488 * compiler has support to do so.
9a8ab1c3 Daniel Santos 2013-02-21 489 */
9a8ab1c3 Daniel Santos 2013-02-21 490 #define compiletime_assert(condition, msg) \
9a8ab1c3 Daniel Santos 2013-02-21 @491 _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
9a8ab1c3 Daniel Santos 2013-02-21 492
47933ad4 Peter Zijlstra 2013-11-06 493 #define compiletime_assert_atomic_type(t) \
47933ad4 Peter Zijlstra 2013-11-06 494 compiletime_assert(__native_word(t), \
47933ad4 Peter Zijlstra 2013-11-06 495 "Need native word sized stores/loads for atomicity.")
47933ad4 Peter Zijlstra 2013-11-06 496
9c3cdc1f Linus Torvalds 2008-05-10 497 /*
9c3cdc1f Linus Torvalds 2008-05-10 498 * Prevent the compiler from merging or refetching accesses. The compiler
9c3cdc1f Linus Torvalds 2008-05-10 499 * is also forbidden from reordering successive instances of ACCESS_ONCE(),
:::::: The code at line 491 was first introduced by commit
:::::: 9a8ab1c39970a4938a72d94e6fd13be88a797590 bug.h, compiler.h: introduce compiletime_assert & BUILD_BUG_ON_MSG
:::::: TO: Daniel Santos <daniel.santos@pobox.com>
:::::: CC: Linus Torvalds <torvalds@linux-foundation.org>
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 49942 bytes --]
[-- Attachment #3: Type: text/plain, Size: 183 bytes --]
_______________________________________________
Virtualization mailing list
Virtualization@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/virtualization
^ permalink raw reply [flat|nested] 25+ messages in thread
* [PATCH v7 0/6] Implement qspinlock/pv-qspinlock on ppc
@ 2016-09-19 9:23 ` Pan Xinhui
0 siblings, 0 replies; 25+ messages in thread
From: Pan Xinhui @ 2016-09-19 9:23 UTC (permalink / raw)
To: linux-kernel, linuxppc-dev
Cc: benh, paulus, mpe, peterz, mingo, paulmck, waiman.long,
xinhui.pan, virtualization
Hi All,
this is the fairlock patchset. You can apply them and build successfully.
patches are based on 4.8-rc4.
qspinlock can avoid waiter starved issue. It has about the same speed in
single-thread and it can be much faster in high contention situations
especially when the spinlock is embedded within the data structure to be
protected.
v6 -> v7:
rebase onto 4.8-rc4
no changelog anymore, sorry for that. I hope there is a very careful review.
Todo:
we can save one function call overhead. As we can use feature-fixup to patch
the binary code. Currently there is pv_lock_ops->lock(lock) and ->unlock(lock) to acquire/release the lock.
some benchmark result below
perf bench
these numbers are ops per sec, So the higher the better.
*******************************************
on pSeries with 32 vcpus, 32Gb memory, pHyp.
------------------------------------------------------------------------------------
test case | pv-qspinlock | qspinlock | current-spinlock
------------------------------------------------------------------------------------
futex hash | 618572 | 552332 | 553788
futex lock-pi | 364 | 364 | 364
sched pipe | 78984 | 76060 | 81454
------------------------------------------------------------------------------------
unix bench:
these numbers are scores, So the higher the better.
************************************************
on PowerNV with 16 cores(cpus) (smt off), 32Gb memory:
-------------
pv-qspinlock and qspinlock have very similar results because pv-qspinlock use native version
which is only having one callback overhead
------------------------------------------------------------------------------------
test case | pv-qspinlock and qspinlock | current-spinlock
------------------------------------------------------------------------------------
Execl Throughput 761.1 761.4
File Copy 1024 bufsize 2000 maxblocks 1259.8 1286.6
File Copy 256 bufsize 500 maxblocks 782.2 790.3
File Copy 4096 bufsize 8000 maxblocks 2741.5 2817.4
Pipe Throughput 1063.2 1036.7
Pipe-based Context Switching 284.7 281.1
Process Creation 679.6 649.1
Shell Scripts (1 concurrent) 1933.2 1922.9
Shell Scripts (8 concurrent) 5003.3 4899.8
System Call Overhead 900.6 896.8
==========================
System Benchmarks Index Score 1139.3 1133.0
--------------------------------------------------------------------------- ---------
*******************************************
on pSeries with 32 vcpus, 32Gb memory, pHyp.
------------------------------------------------------------------------------------
test case | pv-qspinlock | qspinlock | current-spinlock
------------------------------------------------------------------------------------
Execl Throughput 877.1 891.2 872.8
File Copy 1024 bufsize 2000 maxblocks 1390.4 1399.2 1395.0
File Copy 256 bufsize 500 maxblocks 882.4 889.5 881.8
File Copy 4096 bufsize 8000 maxblocks 3112.3 3113.4 3121.7
Pipe Throughput 1095.8 1162.6 1158.5
Pipe-based Context Switching 194.9 192.7 200.7
Process Creation 518.4 526.4 509.1
Shell Scripts (1 concurrent) 1401.9 1413.9 1402.2
Shell Scripts (8 concurrent) 3215.6 3246.6 3229.1
System Call Overhead 833.2 892.4 888.1
====================================
System Benchmarks Index Score 1033.7 1052.5 1047.8
------------------------------------------------------------------------------------
******************************************
on pSeries with 32 vcpus, 16Gb memory, KVM.
------------------------------------------------------------------------------------
test case | pv-qspinlock | qspinlock | current-spinlock
------------------------------------------------------------------------------------
Execl Throughput 497.4 518.7 497.8
File Copy 1024 bufsize 2000 maxblocks 1368.8 1390.1 1343.3
File Copy 256 bufsize 500 maxblocks 857.7 859.8 831.4
File Copy 4096 bufsize 8000 maxblocks 2851.7 2838.1 2785.5
Pipe Throughput 1221.9 1265.3 1250.4
Pipe-based Context Switching 529.8 578.1 564.2
Process Creation 408.4 421.6 287.6
Shell Scripts (1 concurrent) 1201.8 1215.3 1185.8
Shell Scripts (8 concurrent) 3758.4 3799.3 3878.9
System Call Overhead 1008.3 1122.6 1134.2
=====================================
System Benchmarks Index Score 1072.0 1108.9 1050.6
------------------------------------------------------------------------------------
Pan Xinhui (6):
pv-qspinlock: use cmpxchg_release in __pv_queued_spin_unlock
powerpc/qspinlock: powerpc support qspinlock
powerpc: pseries/Kconfig: Add qspinlock build config
powerpc: lib/locks.c: Add cpu yield/wake helper function
powerpc/pv-qspinlock: powerpc support pv-qspinlock
powerpc: pSeries: Add pv-qspinlock build config/make
arch/powerpc/include/asm/qspinlock.h | 93 +++++++++++++
arch/powerpc/include/asm/qspinlock_paravirt.h | 36 +++++
.../powerpc/include/asm/qspinlock_paravirt_types.h | 13 ++
arch/powerpc/include/asm/spinlock.h | 35 +++--
arch/powerpc/include/asm/spinlock_types.h | 4 +
arch/powerpc/kernel/Makefile | 1 +
arch/powerpc/kernel/paravirt.c | 153 +++++++++++++++++++++
arch/powerpc/lib/locks.c | 122 ++++++++++++++++
arch/powerpc/platforms/pseries/Kconfig | 9 ++
arch/powerpc/platforms/pseries/setup.c | 5 +
kernel/locking/qspinlock_paravirt.h | 2 +-
11 files changed, 459 insertions(+), 14 deletions(-)
create mode 100644 arch/powerpc/include/asm/qspinlock.h
create mode 100644 arch/powerpc/include/asm/qspinlock_paravirt.h
create mode 100644 arch/powerpc/include/asm/qspinlock_paravirt_types.h
create mode 100644 arch/powerpc/kernel/paravirt.c
--
2.4.11
^ permalink raw reply [flat|nested] 25+ messages in thread
* [PATCH v7 0/6] Implement qspinlock/pv-qspinlock on ppc
@ 2016-09-19 9:23 ` Pan Xinhui
0 siblings, 0 replies; 25+ messages in thread
From: Pan Xinhui @ 2016-09-19 9:23 UTC (permalink / raw)
To: linux-kernel, linuxppc-dev
Cc: xinhui.pan, peterz, benh, waiman.long, virtualization, mingo,
paulus, mpe, paulmck
Hi All,
this is the fairlock patchset. You can apply them and build successfully.
patches are based on 4.8-rc4.
qspinlock can avoid waiter starved issue. It has about the same speed in
single-thread and it can be much faster in high contention situations
especially when the spinlock is embedded within the data structure to be
protected.
v6 -> v7:
rebase onto 4.8-rc4
no changelog anymore, sorry for that. I hope there is a very careful review.
Todo:
we can save one function call overhead. As we can use feature-fixup to patch
the binary code. Currently there is pv_lock_ops->lock(lock) and ->unlock(lock) to acquire/release the lock.
some benchmark result below
perf bench
these numbers are ops per sec, So the higher the better.
*******************************************
on pSeries with 32 vcpus, 32Gb memory, pHyp.
------------------------------------------------------------------------------------
test case | pv-qspinlock | qspinlock | current-spinlock
------------------------------------------------------------------------------------
futex hash | 618572 | 552332 | 553788
futex lock-pi | 364 | 364 | 364
sched pipe | 78984 | 76060 | 81454
------------------------------------------------------------------------------------
unix bench:
these numbers are scores, So the higher the better.
************************************************
on PowerNV with 16 cores(cpus) (smt off), 32Gb memory:
-------------
pv-qspinlock and qspinlock have very similar results because pv-qspinlock use native version
which is only having one callback overhead
------------------------------------------------------------------------------------
test case | pv-qspinlock and qspinlock | current-spinlock
------------------------------------------------------------------------------------
Execl Throughput 761.1 761.4
File Copy 1024 bufsize 2000 maxblocks 1259.8 1286.6
File Copy 256 bufsize 500 maxblocks 782.2 790.3
File Copy 4096 bufsize 8000 maxblocks 2741.5 2817.4
Pipe Throughput 1063.2 1036.7
Pipe-based Context Switching 284.7 281.1
Process Creation 679.6 649.1
Shell Scripts (1 concurrent) 1933.2 1922.9
Shell Scripts (8 concurrent) 5003.3 4899.8
System Call Overhead 900.6 896.8
==========================
System Benchmarks Index Score 1139.3 1133.0
--------------------------------------------------------------------------- ---------
*******************************************
on pSeries with 32 vcpus, 32Gb memory, pHyp.
------------------------------------------------------------------------------------
test case | pv-qspinlock | qspinlock | current-spinlock
------------------------------------------------------------------------------------
Execl Throughput 877.1 891.2 872.8
File Copy 1024 bufsize 2000 maxblocks 1390.4 1399.2 1395.0
File Copy 256 bufsize 500 maxblocks 882.4 889.5 881.8
File Copy 4096 bufsize 8000 maxblocks 3112.3 3113.4 3121.7
Pipe Throughput 1095.8 1162.6 1158.5
Pipe-based Context Switching 194.9 192.7 200.7
Process Creation 518.4 526.4 509.1
Shell Scripts (1 concurrent) 1401.9 1413.9 1402.2
Shell Scripts (8 concurrent) 3215.6 3246.6 3229.1
System Call Overhead 833.2 892.4 888.1
====================================
System Benchmarks Index Score 1033.7 1052.5 1047.8
------------------------------------------------------------------------------------
******************************************
on pSeries with 32 vcpus, 16Gb memory, KVM.
------------------------------------------------------------------------------------
test case | pv-qspinlock | qspinlock | current-spinlock
------------------------------------------------------------------------------------
Execl Throughput 497.4 518.7 497.8
File Copy 1024 bufsize 2000 maxblocks 1368.8 1390.1 1343.3
File Copy 256 bufsize 500 maxblocks 857.7 859.8 831.4
File Copy 4096 bufsize 8000 maxblocks 2851.7 2838.1 2785.5
Pipe Throughput 1221.9 1265.3 1250.4
Pipe-based Context Switching 529.8 578.1 564.2
Process Creation 408.4 421.6 287.6
Shell Scripts (1 concurrent) 1201.8 1215.3 1185.8
Shell Scripts (8 concurrent) 3758.4 3799.3 3878.9
System Call Overhead 1008.3 1122.6 1134.2
=====================================
System Benchmarks Index Score 1072.0 1108.9 1050.6
------------------------------------------------------------------------------------
Pan Xinhui (6):
pv-qspinlock: use cmpxchg_release in __pv_queued_spin_unlock
powerpc/qspinlock: powerpc support qspinlock
powerpc: pseries/Kconfig: Add qspinlock build config
powerpc: lib/locks.c: Add cpu yield/wake helper function
powerpc/pv-qspinlock: powerpc support pv-qspinlock
powerpc: pSeries: Add pv-qspinlock build config/make
arch/powerpc/include/asm/qspinlock.h | 93 +++++++++++++
arch/powerpc/include/asm/qspinlock_paravirt.h | 36 +++++
.../powerpc/include/asm/qspinlock_paravirt_types.h | 13 ++
arch/powerpc/include/asm/spinlock.h | 35 +++--
arch/powerpc/include/asm/spinlock_types.h | 4 +
arch/powerpc/kernel/Makefile | 1 +
arch/powerpc/kernel/paravirt.c | 153 +++++++++++++++++++++
arch/powerpc/lib/locks.c | 122 ++++++++++++++++
arch/powerpc/platforms/pseries/Kconfig | 9 ++
arch/powerpc/platforms/pseries/setup.c | 5 +
kernel/locking/qspinlock_paravirt.h | 2 +-
11 files changed, 459 insertions(+), 14 deletions(-)
create mode 100644 arch/powerpc/include/asm/qspinlock.h
create mode 100644 arch/powerpc/include/asm/qspinlock_paravirt.h
create mode 100644 arch/powerpc/include/asm/qspinlock_paravirt_types.h
create mode 100644 arch/powerpc/kernel/paravirt.c
--
2.4.11
^ permalink raw reply [flat|nested] 25+ messages in thread
* [PATCH v7 1/6] pv-qspinlock: use cmpxchg_release in __pv_queued_spin_unlock
2016-09-19 9:23 ` Pan Xinhui
@ 2016-09-19 9:23 ` Pan Xinhui
-1 siblings, 0 replies; 25+ messages in thread
From: Pan Xinhui @ 2016-09-19 9:23 UTC (permalink / raw)
To: linux-kernel, linuxppc-dev
Cc: benh, paulus, mpe, peterz, mingo, paulmck, waiman.long,
xinhui.pan, virtualization
cmpxchg_release() is more lighweight than cmpxchg() on some archs(e.g.
PPC), moreover, in __pv_queued_spin_unlock() we only needs a RELEASE in
the fast path(pairing with *_try_lock() or *_lock()). And the slow path
has smp_store_release too. So it's safe to use cmpxchg_release here.
Suggested-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Pan Xinhui <xinhui.pan@linux.vnet.ibm.com>
---
kernel/locking/qspinlock_paravirt.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/kernel/locking/qspinlock_paravirt.h b/kernel/locking/qspinlock_paravirt.h
index 8a99abf..ce655aa 100644
--- a/kernel/locking/qspinlock_paravirt.h
+++ b/kernel/locking/qspinlock_paravirt.h
@@ -544,7 +544,7 @@ __visible void __pv_queued_spin_unlock(struct qspinlock *lock)
* unhash. Otherwise it would be possible to have multiple @lock
* entries, which would be BAD.
*/
- locked = cmpxchg(&l->locked, _Q_LOCKED_VAL, 0);
+ locked = cmpxchg_release(&l->locked, _Q_LOCKED_VAL, 0);
if (likely(locked == _Q_LOCKED_VAL))
return;
--
2.4.11
^ permalink raw reply related [flat|nested] 25+ messages in thread
* [PATCH v7 1/6] pv-qspinlock: use cmpxchg_release in __pv_queued_spin_unlock
@ 2016-09-19 9:23 ` Pan Xinhui
0 siblings, 0 replies; 25+ messages in thread
From: Pan Xinhui @ 2016-09-19 9:23 UTC (permalink / raw)
To: linux-kernel, linuxppc-dev
Cc: xinhui.pan, peterz, benh, waiman.long, virtualization, mingo,
paulus, mpe, paulmck
cmpxchg_release() is more lighweight than cmpxchg() on some archs(e.g.
PPC), moreover, in __pv_queued_spin_unlock() we only needs a RELEASE in
the fast path(pairing with *_try_lock() or *_lock()). And the slow path
has smp_store_release too. So it's safe to use cmpxchg_release here.
Suggested-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Pan Xinhui <xinhui.pan@linux.vnet.ibm.com>
---
kernel/locking/qspinlock_paravirt.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/kernel/locking/qspinlock_paravirt.h b/kernel/locking/qspinlock_paravirt.h
index 8a99abf..ce655aa 100644
--- a/kernel/locking/qspinlock_paravirt.h
+++ b/kernel/locking/qspinlock_paravirt.h
@@ -544,7 +544,7 @@ __visible void __pv_queued_spin_unlock(struct qspinlock *lock)
* unhash. Otherwise it would be possible to have multiple @lock
* entries, which would be BAD.
*/
- locked = cmpxchg(&l->locked, _Q_LOCKED_VAL, 0);
+ locked = cmpxchg_release(&l->locked, _Q_LOCKED_VAL, 0);
if (likely(locked == _Q_LOCKED_VAL))
return;
--
2.4.11
^ permalink raw reply related [flat|nested] 25+ messages in thread
* [PATCH v7 2/6] powerpc/qspinlock: powerpc support qspinlock
2016-09-19 9:23 ` Pan Xinhui
` (2 preceding siblings ...)
(?)
@ 2016-09-19 9:23 ` Pan Xinhui
-1 siblings, 0 replies; 25+ messages in thread
From: Pan Xinhui @ 2016-09-19 9:23 UTC (permalink / raw)
To: linux-kernel, linuxppc-dev
Cc: benh, paulus, mpe, peterz, mingo, paulmck, waiman.long,
xinhui.pan, virtualization
This patch add basic code to enable qspinlock on powerpc. qspinlock is
one kind of fairlock implemention. And seen some performance improvement
under some scenarios.
queued_spin_unlock() release the lock by just one write of NULL to the
->locked field which sits at different places in the two endianness
system.
We override some arch_spin_xxx as powerpc has io_sync stuff which makes
sure the io operations are protected by the lock correctly.
There is another special case, see commit
2c610022711 ("locking/qspinlock: Fix spin_unlock_wait() some more")
Signed-off-by: Pan Xinhui <xinhui.pan@linux.vnet.ibm.com>
---
arch/powerpc/include/asm/qspinlock.h | 66 +++++++++++++++++++++++++++++++
arch/powerpc/include/asm/spinlock.h | 31 +++++++++------
arch/powerpc/include/asm/spinlock_types.h | 4 ++
arch/powerpc/lib/locks.c | 59 +++++++++++++++++++++++++++
4 files changed, 147 insertions(+), 13 deletions(-)
create mode 100644 arch/powerpc/include/asm/qspinlock.h
diff --git a/arch/powerpc/include/asm/qspinlock.h b/arch/powerpc/include/asm/qspinlock.h
new file mode 100644
index 0000000..881a186
--- /dev/null
+++ b/arch/powerpc/include/asm/qspinlock.h
@@ -0,0 +1,66 @@
+#ifndef _ASM_POWERPC_QSPINLOCK_H
+#define _ASM_POWERPC_QSPINLOCK_H
+
+#include <asm-generic/qspinlock_types.h>
+
+#define SPIN_THRESHOLD (1 << 15)
+#define queued_spin_unlock queued_spin_unlock
+#define queued_spin_is_locked queued_spin_is_locked
+#define queued_spin_unlock_wait queued_spin_unlock_wait
+
+extern void queued_spin_unlock_wait(struct qspinlock *lock);
+
+static inline u8 * __qspinlock_lock_byte(struct qspinlock *lock)
+{
+ return (u8 *)lock + 3 * IS_BUILTIN(CONFIG_CPU_BIG_ENDIAN);
+}
+
+static inline void queued_spin_unlock(struct qspinlock *lock)
+{
+ /* release semantics is required */
+ smp_store_release(__qspinlock_lock_byte(lock), 0);
+}
+
+static inline int queued_spin_is_locked(struct qspinlock *lock)
+{
+ smp_mb();
+ return atomic_read(&lock->val);
+}
+
+#include <asm-generic/qspinlock.h>
+
+/* we need override it as ppc has io_sync stuff */
+#undef arch_spin_trylock
+#undef arch_spin_lock
+#undef arch_spin_lock_flags
+#undef arch_spin_unlock
+#define arch_spin_trylock arch_spin_trylock
+#define arch_spin_lock arch_spin_lock
+#define arch_spin_lock_flags arch_spin_lock_flags
+#define arch_spin_unlock arch_spin_unlock
+
+static inline int arch_spin_trylock(arch_spinlock_t *lock)
+{
+ CLEAR_IO_SYNC;
+ return queued_spin_trylock(lock);
+}
+
+static inline void arch_spin_lock(arch_spinlock_t *lock)
+{
+ CLEAR_IO_SYNC;
+ queued_spin_lock(lock);
+}
+
+static inline
+void arch_spin_lock_flags(arch_spinlock_t *lock, unsigned long flags)
+{
+ CLEAR_IO_SYNC;
+ queued_spin_lock(lock);
+}
+
+static inline void arch_spin_unlock(arch_spinlock_t *lock)
+{
+ SYNC_IO;
+ queued_spin_unlock(lock);
+}
+#endif /* _ASM_POWERPC_QSPINLOCK_H */
diff --git a/arch/powerpc/include/asm/spinlock.h b/arch/powerpc/include/asm/spinlock.h
index fa37fe9..6aef8dd 100644
--- a/arch/powerpc/include/asm/spinlock.h
+++ b/arch/powerpc/include/asm/spinlock.h
@@ -52,6 +52,23 @@
#define SYNC_IO
#endif
+#if defined(CONFIG_PPC_SPLPAR)
+/* We only yield to the hypervisor if we are in shared processor mode */
+#define SHARED_PROCESSOR (lppaca_shared_proc(local_paca->lppaca_ptr))
+extern void __spin_yield(arch_spinlock_t *lock);
+extern void __rw_yield(arch_rwlock_t *lock);
+#else /* SPLPAR */
+#define __spin_yield(x) barrier()
+#define __rw_yield(x) barrier()
+#define SHARED_PROCESSOR 0
+#endif
+
+#ifdef CONFIG_QUEUED_SPINLOCKS
+#include <asm/qspinlock.h>
+#else
+
+#define arch_spin_relax(lock) __spin_yield(lock)
+
static __always_inline int arch_spin_value_unlocked(arch_spinlock_t lock)
{
return lock.slock == 0;
@@ -106,18 +123,6 @@ static inline int arch_spin_trylock(arch_spinlock_t *lock)
* held. Conveniently, we have a word in the paca that holds this
* value.
*/
-
-#if defined(CONFIG_PPC_SPLPAR)
-/* We only yield to the hypervisor if we are in shared processor mode */
-#define SHARED_PROCESSOR (lppaca_shared_proc(local_paca->lppaca_ptr))
-extern void __spin_yield(arch_spinlock_t *lock);
-extern void __rw_yield(arch_rwlock_t *lock);
-#else /* SPLPAR */
-#define __spin_yield(x) barrier()
-#define __rw_yield(x) barrier()
-#define SHARED_PROCESSOR 0
-#endif
-
static inline void arch_spin_lock(arch_spinlock_t *lock)
{
CLEAR_IO_SYNC;
@@ -195,6 +200,7 @@ out:
smp_mb();
}
+#endif /* !CONFIG_QUEUED_SPINLOCKS */
/*
* Read-write spinlocks, allowing multiple readers
* but only one writer.
@@ -330,7 +336,6 @@ static inline void arch_write_unlock(arch_rwlock_t *rw)
#define arch_read_lock_flags(lock, flags) arch_read_lock(lock)
#define arch_write_lock_flags(lock, flags) arch_write_lock(lock)
-#define arch_spin_relax(lock) __spin_yield(lock)
#define arch_read_relax(lock) __rw_yield(lock)
#define arch_write_relax(lock) __rw_yield(lock)
diff --git a/arch/powerpc/include/asm/spinlock_types.h b/arch/powerpc/include/asm/spinlock_types.h
index 2351adc..bd7144e 100644
--- a/arch/powerpc/include/asm/spinlock_types.h
+++ b/arch/powerpc/include/asm/spinlock_types.h
@@ -5,11 +5,15 @@
# error "please don't include this file directly"
#endif
+#ifdef CONFIG_QUEUED_SPINLOCKS
+#include <asm-generic/qspinlock_types.h>
+#else
typedef struct {
volatile unsigned int slock;
} arch_spinlock_t;
#define __ARCH_SPIN_LOCK_UNLOCKED { 0 }
+#endif
typedef struct {
volatile signed int lock;
diff --git a/arch/powerpc/lib/locks.c b/arch/powerpc/lib/locks.c
index b7b1237..6574626 100644
--- a/arch/powerpc/lib/locks.c
+++ b/arch/powerpc/lib/locks.c
@@ -23,6 +23,7 @@
#include <asm/hvcall.h>
#include <asm/smp.h>
+#ifndef CONFIG_QUEUED_SPINLOCKS
void __spin_yield(arch_spinlock_t *lock)
{
unsigned int lock_value, holder_cpu, yield_count;
@@ -42,6 +43,7 @@ void __spin_yield(arch_spinlock_t *lock)
get_hard_smp_processor_id(holder_cpu), yield_count);
}
EXPORT_SYMBOL_GPL(__spin_yield);
+#endif
/*
* Waiting for a read lock or a write lock on a rwlock...
@@ -68,3 +70,60 @@ void __rw_yield(arch_rwlock_t *rw)
get_hard_smp_processor_id(holder_cpu), yield_count);
}
#endif
+
+#ifdef CONFIG_QUEUED_SPINLOCKS
+/*
+ * This forbid we load an old value in another LL/SC. Because the SC here force
+ * another LL/SC repeat. So we guarantee all loads in another LL and SC will
+ * read correct value.
+ */
+static inline u32 atomic_read_sync(atomic_t *v)
+{
+ u32 val;
+
+ __asm__ __volatile__(
+"1: " PPC_LWARX(%0, 0, %2, 0) "\n"
+" stwcx. %0, 0, %2\n"
+" bne- 1b\n"
+ : "=&r" (val), "+m" (*v)
+ : "r" (v)
+ : "cr0", "xer");
+
+ return val;
+}
+
+void queued_spin_unlock_wait(struct qspinlock *lock)
+{
+
+ u32 val;
+
+ smp_mb();
+
+ /*
+ * copied from generic queue_spin_unlock_wait with little modification
+ */
+ for (;;) {
+ /* need _sync, as we might race with another LL/SC in lock()*/
+ val = atomic_read_sync(&lock->val);
+
+ if (!val) /* not locked, we're done */
+ goto done;
+
+ if (val & _Q_LOCKED_MASK) /* locked, go wait for unlock */
+ break;
+
+ /* not locked, but pending, wait until we observe the lock */
+ cpu_relax();
+ }
+
+ /*
+ * any unlock is good. And need not _sync, as ->val is set by the SC in
+ * unlock(), any loads in lock() must see the correct value.
+ */
+ while (atomic_read(&lock->val) & _Q_LOCKED_MASK)
+ cpu_relax();
+done:
+ smp_mb();
+}
+EXPORT_SYMBOL(queued_spin_unlock_wait);
+#endif
--
2.4.11
^ permalink raw reply related [flat|nested] 25+ messages in thread
* [PATCH v7 2/6] powerpc/qspinlock: powerpc support qspinlock
2016-09-19 9:23 ` Pan Xinhui
(?)
(?)
@ 2016-09-19 9:23 ` Pan Xinhui
-1 siblings, 0 replies; 25+ messages in thread
From: Pan Xinhui @ 2016-09-19 9:23 UTC (permalink / raw)
To: linux-kernel, linuxppc-dev
Cc: xinhui.pan, peterz, benh, waiman.long, virtualization, mingo,
paulus, mpe, paulmck
This patch add basic code to enable qspinlock on powerpc. qspinlock is
one kind of fairlock implemention. And seen some performance improvement
under some scenarios.
queued_spin_unlock() release the lock by just one write of NULL to the
->locked field which sits at different places in the two endianness
system.
We override some arch_spin_xxx as powerpc has io_sync stuff which makes
sure the io operations are protected by the lock correctly.
There is another special case, see commit
2c610022711 ("locking/qspinlock: Fix spin_unlock_wait() some more")
Signed-off-by: Pan Xinhui <xinhui.pan@linux.vnet.ibm.com>
---
arch/powerpc/include/asm/qspinlock.h | 66 +++++++++++++++++++++++++++++++
arch/powerpc/include/asm/spinlock.h | 31 +++++++++------
arch/powerpc/include/asm/spinlock_types.h | 4 ++
arch/powerpc/lib/locks.c | 59 +++++++++++++++++++++++++++
4 files changed, 147 insertions(+), 13 deletions(-)
create mode 100644 arch/powerpc/include/asm/qspinlock.h
diff --git a/arch/powerpc/include/asm/qspinlock.h b/arch/powerpc/include/asm/qspinlock.h
new file mode 100644
index 0000000..881a186
--- /dev/null
+++ b/arch/powerpc/include/asm/qspinlock.h
@@ -0,0 +1,66 @@
+#ifndef _ASM_POWERPC_QSPINLOCK_H
+#define _ASM_POWERPC_QSPINLOCK_H
+
+#include <asm-generic/qspinlock_types.h>
+
+#define SPIN_THRESHOLD (1 << 15)
+#define queued_spin_unlock queued_spin_unlock
+#define queued_spin_is_locked queued_spin_is_locked
+#define queued_spin_unlock_wait queued_spin_unlock_wait
+
+extern void queued_spin_unlock_wait(struct qspinlock *lock);
+
+static inline u8 * __qspinlock_lock_byte(struct qspinlock *lock)
+{
+ return (u8 *)lock + 3 * IS_BUILTIN(CONFIG_CPU_BIG_ENDIAN);
+}
+
+static inline void queued_spin_unlock(struct qspinlock *lock)
+{
+ /* release semantics is required */
+ smp_store_release(__qspinlock_lock_byte(lock), 0);
+}
+
+static inline int queued_spin_is_locked(struct qspinlock *lock)
+{
+ smp_mb();
+ return atomic_read(&lock->val);
+}
+
+#include <asm-generic/qspinlock.h>
+
+/* we need override it as ppc has io_sync stuff */
+#undef arch_spin_trylock
+#undef arch_spin_lock
+#undef arch_spin_lock_flags
+#undef arch_spin_unlock
+#define arch_spin_trylock arch_spin_trylock
+#define arch_spin_lock arch_spin_lock
+#define arch_spin_lock_flags arch_spin_lock_flags
+#define arch_spin_unlock arch_spin_unlock
+
+static inline int arch_spin_trylock(arch_spinlock_t *lock)
+{
+ CLEAR_IO_SYNC;
+ return queued_spin_trylock(lock);
+}
+
+static inline void arch_spin_lock(arch_spinlock_t *lock)
+{
+ CLEAR_IO_SYNC;
+ queued_spin_lock(lock);
+}
+
+static inline
+void arch_spin_lock_flags(arch_spinlock_t *lock, unsigned long flags)
+{
+ CLEAR_IO_SYNC;
+ queued_spin_lock(lock);
+}
+
+static inline void arch_spin_unlock(arch_spinlock_t *lock)
+{
+ SYNC_IO;
+ queued_spin_unlock(lock);
+}
+#endif /* _ASM_POWERPC_QSPINLOCK_H */
diff --git a/arch/powerpc/include/asm/spinlock.h b/arch/powerpc/include/asm/spinlock.h
index fa37fe9..6aef8dd 100644
--- a/arch/powerpc/include/asm/spinlock.h
+++ b/arch/powerpc/include/asm/spinlock.h
@@ -52,6 +52,23 @@
#define SYNC_IO
#endif
+#if defined(CONFIG_PPC_SPLPAR)
+/* We only yield to the hypervisor if we are in shared processor mode */
+#define SHARED_PROCESSOR (lppaca_shared_proc(local_paca->lppaca_ptr))
+extern void __spin_yield(arch_spinlock_t *lock);
+extern void __rw_yield(arch_rwlock_t *lock);
+#else /* SPLPAR */
+#define __spin_yield(x) barrier()
+#define __rw_yield(x) barrier()
+#define SHARED_PROCESSOR 0
+#endif
+
+#ifdef CONFIG_QUEUED_SPINLOCKS
+#include <asm/qspinlock.h>
+#else
+
+#define arch_spin_relax(lock) __spin_yield(lock)
+
static __always_inline int arch_spin_value_unlocked(arch_spinlock_t lock)
{
return lock.slock == 0;
@@ -106,18 +123,6 @@ static inline int arch_spin_trylock(arch_spinlock_t *lock)
* held. Conveniently, we have a word in the paca that holds this
* value.
*/
-
-#if defined(CONFIG_PPC_SPLPAR)
-/* We only yield to the hypervisor if we are in shared processor mode */
-#define SHARED_PROCESSOR (lppaca_shared_proc(local_paca->lppaca_ptr))
-extern void __spin_yield(arch_spinlock_t *lock);
-extern void __rw_yield(arch_rwlock_t *lock);
-#else /* SPLPAR */
-#define __spin_yield(x) barrier()
-#define __rw_yield(x) barrier()
-#define SHARED_PROCESSOR 0
-#endif
-
static inline void arch_spin_lock(arch_spinlock_t *lock)
{
CLEAR_IO_SYNC;
@@ -195,6 +200,7 @@ out:
smp_mb();
}
+#endif /* !CONFIG_QUEUED_SPINLOCKS */
/*
* Read-write spinlocks, allowing multiple readers
* but only one writer.
@@ -330,7 +336,6 @@ static inline void arch_write_unlock(arch_rwlock_t *rw)
#define arch_read_lock_flags(lock, flags) arch_read_lock(lock)
#define arch_write_lock_flags(lock, flags) arch_write_lock(lock)
-#define arch_spin_relax(lock) __spin_yield(lock)
#define arch_read_relax(lock) __rw_yield(lock)
#define arch_write_relax(lock) __rw_yield(lock)
diff --git a/arch/powerpc/include/asm/spinlock_types.h b/arch/powerpc/include/asm/spinlock_types.h
index 2351adc..bd7144e 100644
--- a/arch/powerpc/include/asm/spinlock_types.h
+++ b/arch/powerpc/include/asm/spinlock_types.h
@@ -5,11 +5,15 @@
# error "please don't include this file directly"
#endif
+#ifdef CONFIG_QUEUED_SPINLOCKS
+#include <asm-generic/qspinlock_types.h>
+#else
typedef struct {
volatile unsigned int slock;
} arch_spinlock_t;
#define __ARCH_SPIN_LOCK_UNLOCKED { 0 }
+#endif
typedef struct {
volatile signed int lock;
diff --git a/arch/powerpc/lib/locks.c b/arch/powerpc/lib/locks.c
index b7b1237..6574626 100644
--- a/arch/powerpc/lib/locks.c
+++ b/arch/powerpc/lib/locks.c
@@ -23,6 +23,7 @@
#include <asm/hvcall.h>
#include <asm/smp.h>
+#ifndef CONFIG_QUEUED_SPINLOCKS
void __spin_yield(arch_spinlock_t *lock)
{
unsigned int lock_value, holder_cpu, yield_count;
@@ -42,6 +43,7 @@ void __spin_yield(arch_spinlock_t *lock)
get_hard_smp_processor_id(holder_cpu), yield_count);
}
EXPORT_SYMBOL_GPL(__spin_yield);
+#endif
/*
* Waiting for a read lock or a write lock on a rwlock...
@@ -68,3 +70,60 @@ void __rw_yield(arch_rwlock_t *rw)
get_hard_smp_processor_id(holder_cpu), yield_count);
}
#endif
+
+#ifdef CONFIG_QUEUED_SPINLOCKS
+/*
+ * This forbid we load an old value in another LL/SC. Because the SC here force
+ * another LL/SC repeat. So we guarantee all loads in another LL and SC will
+ * read correct value.
+ */
+static inline u32 atomic_read_sync(atomic_t *v)
+{
+ u32 val;
+
+ __asm__ __volatile__(
+"1: " PPC_LWARX(%0, 0, %2, 0) "\n"
+" stwcx. %0, 0, %2\n"
+" bne- 1b\n"
+ : "=&r" (val), "+m" (*v)
+ : "r" (v)
+ : "cr0", "xer");
+
+ return val;
+}
+
+void queued_spin_unlock_wait(struct qspinlock *lock)
+{
+
+ u32 val;
+
+ smp_mb();
+
+ /*
+ * copied from generic queue_spin_unlock_wait with little modification
+ */
+ for (;;) {
+ /* need _sync, as we might race with another LL/SC in lock()*/
+ val = atomic_read_sync(&lock->val);
+
+ if (!val) /* not locked, we're done */
+ goto done;
+
+ if (val & _Q_LOCKED_MASK) /* locked, go wait for unlock */
+ break;
+
+ /* not locked, but pending, wait until we observe the lock */
+ cpu_relax();
+ }
+
+ /*
+ * any unlock is good. And need not _sync, as ->val is set by the SC in
+ * unlock(), any loads in lock() must see the correct value.
+ */
+ while (atomic_read(&lock->val) & _Q_LOCKED_MASK)
+ cpu_relax();
+done:
+ smp_mb();
+}
+EXPORT_SYMBOL(queued_spin_unlock_wait);
+#endif
--
2.4.11
^ permalink raw reply related [flat|nested] 25+ messages in thread
* [PATCH v7 3/6] powerpc: pseries/Kconfig: Add qspinlock build config
2016-09-19 9:23 ` Pan Xinhui
@ 2016-09-19 9:23 ` Pan Xinhui
-1 siblings, 0 replies; 25+ messages in thread
From: Pan Xinhui @ 2016-09-19 9:23 UTC (permalink / raw)
To: linux-kernel, linuxppc-dev
Cc: benh, paulus, mpe, peterz, mingo, paulmck, waiman.long,
xinhui.pan, virtualization
pseries will use qspinlock by default.
Signed-off-by: Pan Xinhui <xinhui.pan@linux.vnet.ibm.com>
---
arch/powerpc/platforms/pseries/Kconfig | 1 +
1 file changed, 1 insertion(+)
diff --git a/arch/powerpc/platforms/pseries/Kconfig b/arch/powerpc/platforms/pseries/Kconfig
index bec90fb..f669323 100644
--- a/arch/powerpc/platforms/pseries/Kconfig
+++ b/arch/powerpc/platforms/pseries/Kconfig
@@ -21,6 +21,7 @@ config PPC_PSERIES
select HOTPLUG_CPU if SMP
select ARCH_RANDOM
select PPC_DOORBELL
+ select ARCH_USE_QUEUED_SPINLOCKS
default y
config PPC_SPLPAR
--
2.4.11
^ permalink raw reply related [flat|nested] 25+ messages in thread
* [PATCH v7 3/6] powerpc: pseries/Kconfig: Add qspinlock build config
@ 2016-09-19 9:23 ` Pan Xinhui
0 siblings, 0 replies; 25+ messages in thread
From: Pan Xinhui @ 2016-09-19 9:23 UTC (permalink / raw)
To: linux-kernel, linuxppc-dev
Cc: xinhui.pan, peterz, benh, waiman.long, virtualization, mingo,
paulus, mpe, paulmck
pseries will use qspinlock by default.
Signed-off-by: Pan Xinhui <xinhui.pan@linux.vnet.ibm.com>
---
arch/powerpc/platforms/pseries/Kconfig | 1 +
1 file changed, 1 insertion(+)
diff --git a/arch/powerpc/platforms/pseries/Kconfig b/arch/powerpc/platforms/pseries/Kconfig
index bec90fb..f669323 100644
--- a/arch/powerpc/platforms/pseries/Kconfig
+++ b/arch/powerpc/platforms/pseries/Kconfig
@@ -21,6 +21,7 @@ config PPC_PSERIES
select HOTPLUG_CPU if SMP
select ARCH_RANDOM
select PPC_DOORBELL
+ select ARCH_USE_QUEUED_SPINLOCKS
default y
config PPC_SPLPAR
--
2.4.11
^ permalink raw reply related [flat|nested] 25+ messages in thread
* [PATCH v7 4/6] powerpc: lib/locks.c: Add cpu yield/wake helper function
2016-09-19 9:23 ` Pan Xinhui
` (4 preceding siblings ...)
(?)
@ 2016-09-19 9:23 ` Pan Xinhui
2016-09-22 15:17 ` Boqun Feng
-1 siblings, 1 reply; 25+ messages in thread
From: Pan Xinhui @ 2016-09-19 9:23 UTC (permalink / raw)
To: linux-kernel, linuxppc-dev
Cc: benh, paulus, mpe, peterz, mingo, paulmck, waiman.long,
xinhui.pan, virtualization
Add two corresponding helper functions to support pv-qspinlock.
For normal use, __spin_yield_cpu will confer current vcpu slices to the
target vcpu(say, a lock holder). If target vcpu is not specified or it
is in running state, such conferging to lpar happens or not depends.
Because hcall itself will introduce latency and a little overhead. And
we do NOT want to suffer any latency on some cases, e.g. in interrupt handler.
The second parameter *confer* can indicate such case.
__spin_wake_cpu is simpiler, it will wake up one vcpu regardless of its
current vcpu state.
Signed-off-by: Pan Xinhui <xinhui.pan@linux.vnet.ibm.com>
---
arch/powerpc/include/asm/spinlock.h | 4 +++
arch/powerpc/lib/locks.c | 59 +++++++++++++++++++++++++++++++++++++
2 files changed, 63 insertions(+)
diff --git a/arch/powerpc/include/asm/spinlock.h b/arch/powerpc/include/asm/spinlock.h
index 6aef8dd..abb6b0f 100644
--- a/arch/powerpc/include/asm/spinlock.h
+++ b/arch/powerpc/include/asm/spinlock.h
@@ -56,9 +56,13 @@
/* We only yield to the hypervisor if we are in shared processor mode */
#define SHARED_PROCESSOR (lppaca_shared_proc(local_paca->lppaca_ptr))
extern void __spin_yield(arch_spinlock_t *lock);
+extern void __spin_yield_cpu(int cpu, int confer);
+extern void __spin_wake_cpu(int cpu);
extern void __rw_yield(arch_rwlock_t *lock);
#else /* SPLPAR */
#define __spin_yield(x) barrier()
+#define __spin_yield_cpu(x,y) barrier()
+#define __spin_wake_cpu(x) barrier()
#define __rw_yield(x) barrier()
#define SHARED_PROCESSOR 0
#endif
diff --git a/arch/powerpc/lib/locks.c b/arch/powerpc/lib/locks.c
index 6574626..892df7d 100644
--- a/arch/powerpc/lib/locks.c
+++ b/arch/powerpc/lib/locks.c
@@ -23,6 +23,65 @@
#include <asm/hvcall.h>
#include <asm/smp.h>
+/*
+ * confer our slices to a specified cpu and return. If it is already running or
+ * cpu is -1, then we will check confer. If confer is NULL, we will return
+ * otherwise we confer our slices to lpar.
+ */
+void __spin_yield_cpu(int cpu, int confer)
+{
+ unsigned int holder_cpu = cpu, yield_count;
+
+ if (cpu == -1)
+ goto yield_to_lpar;
+
+ BUG_ON(holder_cpu >= nr_cpu_ids);
+ yield_count = be32_to_cpu(lppaca_of(holder_cpu).yield_count);
+
+ /* if cpu is running, confer slices to lpar conditionally*/
+ if ((yield_count & 1) == 0)
+ goto yield_to_lpar;
+
+ plpar_hcall_norets(H_CONFER,
+ get_hard_smp_processor_id(holder_cpu), yield_count);
+ return;
+
+yield_to_lpar:
+ if (confer)
+ plpar_hcall_norets(H_CONFER, -1, 0);
+}
+EXPORT_SYMBOL_GPL(__spin_yield_cpu);
+
+void __spin_wake_cpu(int cpu)
+{
+ unsigned int holder_cpu = cpu;
+
+ BUG_ON(holder_cpu >= nr_cpu_ids);
+ /*
+ * NOTE: we should always do this hcall regardless of
+ * the yield_count of the holder_cpu.
+ * as thers might be a case like below;
+ * CPU 1 2
+ * yielded = true
+ * if (yielded)
+ * __spin_wake_cpu()
+ * __spin_yield_cpu()
+ *
+ * So we might lose a wake if we check the yield_count and
+ * return directly if the holder_cpu is running.
+ * IOW. do NOT code like below.
+ * yield_count = be32_to_cpu(lppaca_of(holder_cpu).yield_count);
+ * if ((yield_count & 1) == 0)
+ * return;
+ *
+ * a PROD hcall marks the target_cpu proded, which cause the next cede or confer
+ * called on the target_cpu invalid.
+ */
+ plpar_hcall_norets(H_PROD,
+ get_hard_smp_processor_id(holder_cpu));
+}
+EXPORT_SYMBOL_GPL(__spin_wake_cpu);
+
#ifndef CONFIG_QUEUED_SPINLOCKS
void __spin_yield(arch_spinlock_t *lock)
{
--
2.4.11
^ permalink raw reply related [flat|nested] 25+ messages in thread
* [PATCH v7 4/6] powerpc: lib/locks.c: Add cpu yield/wake helper function
2016-09-19 9:23 ` Pan Xinhui
` (5 preceding siblings ...)
(?)
@ 2016-09-19 9:23 ` Pan Xinhui
-1 siblings, 0 replies; 25+ messages in thread
From: Pan Xinhui @ 2016-09-19 9:23 UTC (permalink / raw)
To: linux-kernel, linuxppc-dev
Cc: xinhui.pan, peterz, benh, waiman.long, virtualization, mingo,
paulus, mpe, paulmck
Add two corresponding helper functions to support pv-qspinlock.
For normal use, __spin_yield_cpu will confer current vcpu slices to the
target vcpu(say, a lock holder). If target vcpu is not specified or it
is in running state, such conferging to lpar happens or not depends.
Because hcall itself will introduce latency and a little overhead. And
we do NOT want to suffer any latency on some cases, e.g. in interrupt handler.
The second parameter *confer* can indicate such case.
__spin_wake_cpu is simpiler, it will wake up one vcpu regardless of its
current vcpu state.
Signed-off-by: Pan Xinhui <xinhui.pan@linux.vnet.ibm.com>
---
arch/powerpc/include/asm/spinlock.h | 4 +++
arch/powerpc/lib/locks.c | 59 +++++++++++++++++++++++++++++++++++++
2 files changed, 63 insertions(+)
diff --git a/arch/powerpc/include/asm/spinlock.h b/arch/powerpc/include/asm/spinlock.h
index 6aef8dd..abb6b0f 100644
--- a/arch/powerpc/include/asm/spinlock.h
+++ b/arch/powerpc/include/asm/spinlock.h
@@ -56,9 +56,13 @@
/* We only yield to the hypervisor if we are in shared processor mode */
#define SHARED_PROCESSOR (lppaca_shared_proc(local_paca->lppaca_ptr))
extern void __spin_yield(arch_spinlock_t *lock);
+extern void __spin_yield_cpu(int cpu, int confer);
+extern void __spin_wake_cpu(int cpu);
extern void __rw_yield(arch_rwlock_t *lock);
#else /* SPLPAR */
#define __spin_yield(x) barrier()
+#define __spin_yield_cpu(x,y) barrier()
+#define __spin_wake_cpu(x) barrier()
#define __rw_yield(x) barrier()
#define SHARED_PROCESSOR 0
#endif
diff --git a/arch/powerpc/lib/locks.c b/arch/powerpc/lib/locks.c
index 6574626..892df7d 100644
--- a/arch/powerpc/lib/locks.c
+++ b/arch/powerpc/lib/locks.c
@@ -23,6 +23,65 @@
#include <asm/hvcall.h>
#include <asm/smp.h>
+/*
+ * confer our slices to a specified cpu and return. If it is already running or
+ * cpu is -1, then we will check confer. If confer is NULL, we will return
+ * otherwise we confer our slices to lpar.
+ */
+void __spin_yield_cpu(int cpu, int confer)
+{
+ unsigned int holder_cpu = cpu, yield_count;
+
+ if (cpu == -1)
+ goto yield_to_lpar;
+
+ BUG_ON(holder_cpu >= nr_cpu_ids);
+ yield_count = be32_to_cpu(lppaca_of(holder_cpu).yield_count);
+
+ /* if cpu is running, confer slices to lpar conditionally*/
+ if ((yield_count & 1) == 0)
+ goto yield_to_lpar;
+
+ plpar_hcall_norets(H_CONFER,
+ get_hard_smp_processor_id(holder_cpu), yield_count);
+ return;
+
+yield_to_lpar:
+ if (confer)
+ plpar_hcall_norets(H_CONFER, -1, 0);
+}
+EXPORT_SYMBOL_GPL(__spin_yield_cpu);
+
+void __spin_wake_cpu(int cpu)
+{
+ unsigned int holder_cpu = cpu;
+
+ BUG_ON(holder_cpu >= nr_cpu_ids);
+ /*
+ * NOTE: we should always do this hcall regardless of
+ * the yield_count of the holder_cpu.
+ * as thers might be a case like below;
+ * CPU 1 2
+ * yielded = true
+ * if (yielded)
+ * __spin_wake_cpu()
+ * __spin_yield_cpu()
+ *
+ * So we might lose a wake if we check the yield_count and
+ * return directly if the holder_cpu is running.
+ * IOW. do NOT code like below.
+ * yield_count = be32_to_cpu(lppaca_of(holder_cpu).yield_count);
+ * if ((yield_count & 1) == 0)
+ * return;
+ *
+ * a PROD hcall marks the target_cpu proded, which cause the next cede or confer
+ * called on the target_cpu invalid.
+ */
+ plpar_hcall_norets(H_PROD,
+ get_hard_smp_processor_id(holder_cpu));
+}
+EXPORT_SYMBOL_GPL(__spin_wake_cpu);
+
#ifndef CONFIG_QUEUED_SPINLOCKS
void __spin_yield(arch_spinlock_t *lock)
{
--
2.4.11
^ permalink raw reply related [flat|nested] 25+ messages in thread
* [PATCH v7 5/6] powerpc/pv-qspinlock: powerpc support pv-qspinlock
2016-09-19 9:23 ` Pan Xinhui
@ 2016-09-19 9:23 ` Pan Xinhui
-1 siblings, 0 replies; 25+ messages in thread
From: Pan Xinhui @ 2016-09-19 9:23 UTC (permalink / raw)
To: linux-kernel, linuxppc-dev
Cc: benh, paulus, mpe, peterz, mingo, paulmck, waiman.long,
xinhui.pan, virtualization
The default pv-qspinlock uses qspinlock(native version of pv-qspinlock).
pv_lock initialization should be done in bootstage with irq disabled.
And if we run as a guest with powerKVM/pHyp shared_processor mode,
restore pv_lock_ops callbacks to pv-qspinlock(pv version) which makes
full use of virtualization.
There is a hash table, we store cpu number into it and the key is lock.
So everytime pv_wait can know who is the lock holder by searching the
lock. Also store the lock in a per_cpu struct, and remove it when we own
the lock. Then pv_wait can know which lock we are spinning on. But the
cpu in the hash table might not be the correct lock holder, as for
performace issue, we does not take care of hash conflict.
Also introduce spin_lock_holder, which tells who owns the lock now.
currently the only user is spin_unlock_wait.
Signed-off-by: Pan Xinhui <xinhui.pan@linux.vnet.ibm.com>
---
arch/powerpc/include/asm/qspinlock.h | 29 +++-
arch/powerpc/include/asm/qspinlock_paravirt.h | 36 +++++
.../powerpc/include/asm/qspinlock_paravirt_types.h | 13 ++
arch/powerpc/kernel/paravirt.c | 153 +++++++++++++++++++++
arch/powerpc/lib/locks.c | 8 +-
arch/powerpc/platforms/pseries/setup.c | 5 +
6 files changed, 241 insertions(+), 3 deletions(-)
create mode 100644 arch/powerpc/include/asm/qspinlock_paravirt.h
create mode 100644 arch/powerpc/include/asm/qspinlock_paravirt_types.h
create mode 100644 arch/powerpc/kernel/paravirt.c
diff --git a/arch/powerpc/include/asm/qspinlock.h b/arch/powerpc/include/asm/qspinlock.h
index 881a186..23459fb 100644
--- a/arch/powerpc/include/asm/qspinlock.h
+++ b/arch/powerpc/include/asm/qspinlock.h
@@ -15,7 +15,7 @@ static inline u8 * __qspinlock_lock_byte(struct qspinlock *lock)
return (u8 *)lock + 3 * IS_BUILTIN(CONFIG_CPU_BIG_ENDIAN);
}
-static inline void queued_spin_unlock(struct qspinlock *lock)
+static inline void native_queued_spin_unlock(struct qspinlock *lock)
{
/* release semantics is required */
smp_store_release(__qspinlock_lock_byte(lock), 0);
@@ -27,6 +27,33 @@ static inline int queued_spin_is_locked(struct qspinlock *lock)
return atomic_read(&lock->val);
}
+#ifdef CONFIG_PARAVIRT_SPINLOCKS
+#include <asm/qspinlock_paravirt.h>
+/*
+ * try to know who is the lock holder, however it is not always true
+ * Return:
+ * -1, we did not know the lock holder.
+ * other value, likely is the lock holder.
+ */
+extern int spin_lock_holder(void *lock);
+
+static inline void queued_spin_lock_slowpath(struct qspinlock *lock, u32 val)
+{
+ pv_queued_spin_lock(lock, val);
+}
+
+static inline void queued_spin_unlock(struct qspinlock *lock)
+{
+ pv_queued_spin_unlock(lock);
+}
+#else
+#define spin_lock_holder(l) (-1)
+static inline void queued_spin_unlock(struct qspinlock *lock)
+{
+ native_queued_spin_unlock(lock);
+}
+#endif
+
#include <asm-generic/qspinlock.h>
/* we need override it as ppc has io_sync stuff */
diff --git a/arch/powerpc/include/asm/qspinlock_paravirt.h b/arch/powerpc/include/asm/qspinlock_paravirt.h
new file mode 100644
index 0000000..d87cda0
--- /dev/null
+++ b/arch/powerpc/include/asm/qspinlock_paravirt.h
@@ -0,0 +1,36 @@
+#ifndef CONFIG_PARAVIRT_SPINLOCKS
+#error "do not include this file"
+#endif
+
+#ifndef _ASM_QSPINLOCK_PARAVIRT_H
+#define _ASM_QSPINLOCK_PARAVIRT_H
+
+#include <asm/qspinlock_paravirt_types.h>
+
+extern void pv_lock_init(void);
+extern void native_queued_spin_lock_slowpath(struct qspinlock *lock, u32 val);
+extern void __pv_init_lock_hash(void);
+extern void __pv_queued_spin_lock_slowpath(struct qspinlock *lock, u32 val);
+extern void __pv_queued_spin_unlock(struct qspinlock *lock);
+
+static inline void pv_queued_spin_lock(struct qspinlock *lock, u32 val)
+{
+ pv_lock_op.lock(lock, val);
+}
+
+static inline void pv_queued_spin_unlock(struct qspinlock *lock)
+{
+ pv_lock_op.unlock(lock);
+}
+
+static inline void pv_wait(u8 *ptr, u8 val)
+{
+ pv_lock_op.wait(ptr, val);
+}
+
+static inline void pv_kick(int cpu)
+{
+ pv_lock_op.kick(cpu);
+}
+
+#endif
diff --git a/arch/powerpc/include/asm/qspinlock_paravirt_types.h b/arch/powerpc/include/asm/qspinlock_paravirt_types.h
new file mode 100644
index 0000000..83611ed
--- /dev/null
+++ b/arch/powerpc/include/asm/qspinlock_paravirt_types.h
@@ -0,0 +1,13 @@
+#ifndef _ASM_QSPINLOCK_PARAVIRT_TYPES_H
+#define _ASM_QSPINLOCK_PARAVIRT_TYPES_H
+
+struct pv_lock_ops {
+ void (*lock)(struct qspinlock *lock, u32 val);
+ void (*unlock)(struct qspinlock *lock);
+ void (*wait)(u8 *ptr, u8 val);
+ void (*kick)(int cpu);
+};
+
+extern struct pv_lock_ops pv_lock_op;
+
+#endif
diff --git a/arch/powerpc/kernel/paravirt.c b/arch/powerpc/kernel/paravirt.c
new file mode 100644
index 0000000..e697b17
--- /dev/null
+++ b/arch/powerpc/kernel/paravirt.c
@@ -0,0 +1,153 @@
+/*
+ * 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.
+ */
+
+#include <linux/spinlock.h>
+#include <linux/smp.h>
+#include <linux/hash.h>
+#include <linux/bootmem.h>
+
+/* +2 here is to make sure there is not many conflict*/
+#define NUM_LOCK_CPU_ENTRY_SHIFT (order_base_2(NR_CPUS) + 2)
+#define NUM_LOCK_CPU_ENTRY (1 << NUM_LOCK_CPU_ENTRY_SHIFT)
+/* we can only spin on 4 locks at same time on same cpu*/
+#define NUM_LOCKS_PER_CPU 4
+
+static u16 *hash_lock_cpu_ptr;
+
+struct locks_on_cpu {
+ void *l[NUM_LOCKS_PER_CPU];
+ int count;
+};
+
+static DEFINE_PER_CPU(struct locks_on_cpu, node);
+
+static u16 *hash(void *l)
+{
+ int val = hash_ptr(l, NUM_LOCK_CPU_ENTRY_SHIFT);
+
+ return &hash_lock_cpu_ptr[val];
+}
+
+static void __init init_hash(void)
+{
+ int size = NUM_LOCK_CPU_ENTRY * sizeof(*hash_lock_cpu_ptr);
+
+ hash_lock_cpu_ptr = memblock_virt_alloc(size, 0);
+ memset(hash_lock_cpu_ptr, 0, size);
+}
+
+#define lock_get_holder(l) \
+ ((int)(*hash(l) - 1))
+
+#define lock_set_holder(l) \
+ (*hash(l) = raw_smp_processor_id() + 1)
+
+int spin_lock_holder(void *lock)
+{
+ /* we might run on PowerNV, which has no hash table ptr*/
+ if (hash_lock_cpu_ptr)
+ return lock_get_holder(lock);
+ return -1;
+}
+EXPORT_SYMBOL(spin_lock_holder);
+
+static void *this_cpu_lock(void)
+{
+ struct locks_on_cpu *this_node = this_cpu_ptr(&node);
+ int i = this_node->count - 1;
+
+ return this_node->l[i];
+}
+
+static void cpu_save_lock(void *l)
+{
+ struct locks_on_cpu *this_node = this_cpu_ptr(&node);
+ int i = this_node->count++;
+
+ this_node->l[i] = l;
+}
+
+static void cpu_remove_lock(void *l)
+{
+ __this_cpu_dec(node.count);
+}
+
+static void __native_queued_spin_unlock(struct qspinlock *lock)
+{
+ native_queued_spin_unlock(lock);
+}
+
+static void __pv_lock(struct qspinlock *lock, u32 val)
+{
+ /*
+ * save the lock we are spinning on
+ * pv_wait need know this lock
+ */
+ cpu_save_lock(lock);
+
+ __pv_queued_spin_lock_slowpath(lock, val);
+
+ /* as we win the lock, remove it*/
+ cpu_remove_lock(lock);
+
+ /*
+ * let other spinner know who is the lock holder
+ * we does not need to unset lock holder in unlock()
+ */
+ lock_set_holder(lock);
+}
+
+static void __pv_wait(u8 *ptr, u8 val)
+{
+ void *l = this_cpu_lock();
+ int cpu;
+ int always_confer = !in_interrupt();
+
+ while (READ_ONCE(*ptr) == val) {
+ HMT_low();
+ /*
+ * the lock might be unlocked once and locked again
+ */
+ cpu = lock_get_holder(l);
+
+ /*
+ * the default behavior of __spin_yield_cpu is yielding
+ * our cpu slices to target vcpu or lpar(pHyp or KVM).
+ * consider the latency of hcall itself and the priority of
+ * current task, we can do a optimisation.
+ * IOW, if we are in interrupt, and the target vcpu is running
+ * we do not yield ourself to lpar.
+ */
+ __spin_yield_cpu(cpu, always_confer);
+ }
+ HMT_medium();
+}
+
+static void __pv_kick(int cpu)
+{
+ __spin_wake_cpu(cpu);
+}
+
+struct pv_lock_ops pv_lock_op = {
+ .lock = native_queued_spin_lock_slowpath,
+ .unlock = __native_queued_spin_unlock,
+ .wait = NULL,
+ .kick = NULL,
+};
+EXPORT_SYMBOL(pv_lock_op);
+
+void __init pv_lock_init(void)
+{
+ if (SHARED_PROCESSOR) {
+ init_hash();
+ __pv_init_lock_hash();
+ pv_lock_op.lock = __pv_lock;
+ pv_lock_op.unlock = __pv_queued_spin_unlock;
+ pv_lock_op.wait = __pv_wait;
+ pv_lock_op.kick = __pv_kick;
+ }
+}
diff --git a/arch/powerpc/lib/locks.c b/arch/powerpc/lib/locks.c
index 892df7d..5daa35a 100644
--- a/arch/powerpc/lib/locks.c
+++ b/arch/powerpc/lib/locks.c
@@ -179,8 +179,12 @@ void queued_spin_unlock_wait(struct qspinlock *lock)
* any unlock is good. And need not _sync, as ->val is set by the SC in
* unlock(), any loads in lock() must see the correct value.
*/
- while (atomic_read(&lock->val) & _Q_LOCKED_MASK)
- cpu_relax();
+ while (atomic_read(&lock->val) & _Q_LOCKED_MASK) {
+ HMT_low();
+ if (SHARED_PROCESSOR)
+ __spin_yield_cpu(spin_lock_holder(lock), 0);
+ }
+ HMT_medium();
done:
smp_mb();
}
diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
index 4ffcaa6..672d888 100644
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -487,6 +487,11 @@ static void __init pSeries_setup_arch(void)
}
ppc_md.pcibios_root_bridge_prepare = pseries_root_bridge_prepare;
+
+#ifdef CONFIG_PARAVIRT_SPINLOCKS
+ pv_lock_init();
+#endif
+
}
static int __init pSeries_init_panel(void)
--
2.4.11
^ permalink raw reply related [flat|nested] 25+ messages in thread
* [PATCH v7 5/6] powerpc/pv-qspinlock: powerpc support pv-qspinlock
@ 2016-09-19 9:23 ` Pan Xinhui
0 siblings, 0 replies; 25+ messages in thread
From: Pan Xinhui @ 2016-09-19 9:23 UTC (permalink / raw)
To: linux-kernel, linuxppc-dev
Cc: xinhui.pan, peterz, benh, waiman.long, virtualization, mingo,
paulus, mpe, paulmck
The default pv-qspinlock uses qspinlock(native version of pv-qspinlock).
pv_lock initialization should be done in bootstage with irq disabled.
And if we run as a guest with powerKVM/pHyp shared_processor mode,
restore pv_lock_ops callbacks to pv-qspinlock(pv version) which makes
full use of virtualization.
There is a hash table, we store cpu number into it and the key is lock.
So everytime pv_wait can know who is the lock holder by searching the
lock. Also store the lock in a per_cpu struct, and remove it when we own
the lock. Then pv_wait can know which lock we are spinning on. But the
cpu in the hash table might not be the correct lock holder, as for
performace issue, we does not take care of hash conflict.
Also introduce spin_lock_holder, which tells who owns the lock now.
currently the only user is spin_unlock_wait.
Signed-off-by: Pan Xinhui <xinhui.pan@linux.vnet.ibm.com>
---
arch/powerpc/include/asm/qspinlock.h | 29 +++-
arch/powerpc/include/asm/qspinlock_paravirt.h | 36 +++++
.../powerpc/include/asm/qspinlock_paravirt_types.h | 13 ++
arch/powerpc/kernel/paravirt.c | 153 +++++++++++++++++++++
arch/powerpc/lib/locks.c | 8 +-
arch/powerpc/platforms/pseries/setup.c | 5 +
6 files changed, 241 insertions(+), 3 deletions(-)
create mode 100644 arch/powerpc/include/asm/qspinlock_paravirt.h
create mode 100644 arch/powerpc/include/asm/qspinlock_paravirt_types.h
create mode 100644 arch/powerpc/kernel/paravirt.c
diff --git a/arch/powerpc/include/asm/qspinlock.h b/arch/powerpc/include/asm/qspinlock.h
index 881a186..23459fb 100644
--- a/arch/powerpc/include/asm/qspinlock.h
+++ b/arch/powerpc/include/asm/qspinlock.h
@@ -15,7 +15,7 @@ static inline u8 * __qspinlock_lock_byte(struct qspinlock *lock)
return (u8 *)lock + 3 * IS_BUILTIN(CONFIG_CPU_BIG_ENDIAN);
}
-static inline void queued_spin_unlock(struct qspinlock *lock)
+static inline void native_queued_spin_unlock(struct qspinlock *lock)
{
/* release semantics is required */
smp_store_release(__qspinlock_lock_byte(lock), 0);
@@ -27,6 +27,33 @@ static inline int queued_spin_is_locked(struct qspinlock *lock)
return atomic_read(&lock->val);
}
+#ifdef CONFIG_PARAVIRT_SPINLOCKS
+#include <asm/qspinlock_paravirt.h>
+/*
+ * try to know who is the lock holder, however it is not always true
+ * Return:
+ * -1, we did not know the lock holder.
+ * other value, likely is the lock holder.
+ */
+extern int spin_lock_holder(void *lock);
+
+static inline void queued_spin_lock_slowpath(struct qspinlock *lock, u32 val)
+{
+ pv_queued_spin_lock(lock, val);
+}
+
+static inline void queued_spin_unlock(struct qspinlock *lock)
+{
+ pv_queued_spin_unlock(lock);
+}
+#else
+#define spin_lock_holder(l) (-1)
+static inline void queued_spin_unlock(struct qspinlock *lock)
+{
+ native_queued_spin_unlock(lock);
+}
+#endif
+
#include <asm-generic/qspinlock.h>
/* we need override it as ppc has io_sync stuff */
diff --git a/arch/powerpc/include/asm/qspinlock_paravirt.h b/arch/powerpc/include/asm/qspinlock_paravirt.h
new file mode 100644
index 0000000..d87cda0
--- /dev/null
+++ b/arch/powerpc/include/asm/qspinlock_paravirt.h
@@ -0,0 +1,36 @@
+#ifndef CONFIG_PARAVIRT_SPINLOCKS
+#error "do not include this file"
+#endif
+
+#ifndef _ASM_QSPINLOCK_PARAVIRT_H
+#define _ASM_QSPINLOCK_PARAVIRT_H
+
+#include <asm/qspinlock_paravirt_types.h>
+
+extern void pv_lock_init(void);
+extern void native_queued_spin_lock_slowpath(struct qspinlock *lock, u32 val);
+extern void __pv_init_lock_hash(void);
+extern void __pv_queued_spin_lock_slowpath(struct qspinlock *lock, u32 val);
+extern void __pv_queued_spin_unlock(struct qspinlock *lock);
+
+static inline void pv_queued_spin_lock(struct qspinlock *lock, u32 val)
+{
+ pv_lock_op.lock(lock, val);
+}
+
+static inline void pv_queued_spin_unlock(struct qspinlock *lock)
+{
+ pv_lock_op.unlock(lock);
+}
+
+static inline void pv_wait(u8 *ptr, u8 val)
+{
+ pv_lock_op.wait(ptr, val);
+}
+
+static inline void pv_kick(int cpu)
+{
+ pv_lock_op.kick(cpu);
+}
+
+#endif
diff --git a/arch/powerpc/include/asm/qspinlock_paravirt_types.h b/arch/powerpc/include/asm/qspinlock_paravirt_types.h
new file mode 100644
index 0000000..83611ed
--- /dev/null
+++ b/arch/powerpc/include/asm/qspinlock_paravirt_types.h
@@ -0,0 +1,13 @@
+#ifndef _ASM_QSPINLOCK_PARAVIRT_TYPES_H
+#define _ASM_QSPINLOCK_PARAVIRT_TYPES_H
+
+struct pv_lock_ops {
+ void (*lock)(struct qspinlock *lock, u32 val);
+ void (*unlock)(struct qspinlock *lock);
+ void (*wait)(u8 *ptr, u8 val);
+ void (*kick)(int cpu);
+};
+
+extern struct pv_lock_ops pv_lock_op;
+
+#endif
diff --git a/arch/powerpc/kernel/paravirt.c b/arch/powerpc/kernel/paravirt.c
new file mode 100644
index 0000000..e697b17
--- /dev/null
+++ b/arch/powerpc/kernel/paravirt.c
@@ -0,0 +1,153 @@
+/*
+ * 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.
+ */
+
+#include <linux/spinlock.h>
+#include <linux/smp.h>
+#include <linux/hash.h>
+#include <linux/bootmem.h>
+
+/* +2 here is to make sure there is not many conflict*/
+#define NUM_LOCK_CPU_ENTRY_SHIFT (order_base_2(NR_CPUS) + 2)
+#define NUM_LOCK_CPU_ENTRY (1 << NUM_LOCK_CPU_ENTRY_SHIFT)
+/* we can only spin on 4 locks at same time on same cpu*/
+#define NUM_LOCKS_PER_CPU 4
+
+static u16 *hash_lock_cpu_ptr;
+
+struct locks_on_cpu {
+ void *l[NUM_LOCKS_PER_CPU];
+ int count;
+};
+
+static DEFINE_PER_CPU(struct locks_on_cpu, node);
+
+static u16 *hash(void *l)
+{
+ int val = hash_ptr(l, NUM_LOCK_CPU_ENTRY_SHIFT);
+
+ return &hash_lock_cpu_ptr[val];
+}
+
+static void __init init_hash(void)
+{
+ int size = NUM_LOCK_CPU_ENTRY * sizeof(*hash_lock_cpu_ptr);
+
+ hash_lock_cpu_ptr = memblock_virt_alloc(size, 0);
+ memset(hash_lock_cpu_ptr, 0, size);
+}
+
+#define lock_get_holder(l) \
+ ((int)(*hash(l) - 1))
+
+#define lock_set_holder(l) \
+ (*hash(l) = raw_smp_processor_id() + 1)
+
+int spin_lock_holder(void *lock)
+{
+ /* we might run on PowerNV, which has no hash table ptr*/
+ if (hash_lock_cpu_ptr)
+ return lock_get_holder(lock);
+ return -1;
+}
+EXPORT_SYMBOL(spin_lock_holder);
+
+static void *this_cpu_lock(void)
+{
+ struct locks_on_cpu *this_node = this_cpu_ptr(&node);
+ int i = this_node->count - 1;
+
+ return this_node->l[i];
+}
+
+static void cpu_save_lock(void *l)
+{
+ struct locks_on_cpu *this_node = this_cpu_ptr(&node);
+ int i = this_node->count++;
+
+ this_node->l[i] = l;
+}
+
+static void cpu_remove_lock(void *l)
+{
+ __this_cpu_dec(node.count);
+}
+
+static void __native_queued_spin_unlock(struct qspinlock *lock)
+{
+ native_queued_spin_unlock(lock);
+}
+
+static void __pv_lock(struct qspinlock *lock, u32 val)
+{
+ /*
+ * save the lock we are spinning on
+ * pv_wait need know this lock
+ */
+ cpu_save_lock(lock);
+
+ __pv_queued_spin_lock_slowpath(lock, val);
+
+ /* as we win the lock, remove it*/
+ cpu_remove_lock(lock);
+
+ /*
+ * let other spinner know who is the lock holder
+ * we does not need to unset lock holder in unlock()
+ */
+ lock_set_holder(lock);
+}
+
+static void __pv_wait(u8 *ptr, u8 val)
+{
+ void *l = this_cpu_lock();
+ int cpu;
+ int always_confer = !in_interrupt();
+
+ while (READ_ONCE(*ptr) == val) {
+ HMT_low();
+ /*
+ * the lock might be unlocked once and locked again
+ */
+ cpu = lock_get_holder(l);
+
+ /*
+ * the default behavior of __spin_yield_cpu is yielding
+ * our cpu slices to target vcpu or lpar(pHyp or KVM).
+ * consider the latency of hcall itself and the priority of
+ * current task, we can do a optimisation.
+ * IOW, if we are in interrupt, and the target vcpu is running
+ * we do not yield ourself to lpar.
+ */
+ __spin_yield_cpu(cpu, always_confer);
+ }
+ HMT_medium();
+}
+
+static void __pv_kick(int cpu)
+{
+ __spin_wake_cpu(cpu);
+}
+
+struct pv_lock_ops pv_lock_op = {
+ .lock = native_queued_spin_lock_slowpath,
+ .unlock = __native_queued_spin_unlock,
+ .wait = NULL,
+ .kick = NULL,
+};
+EXPORT_SYMBOL(pv_lock_op);
+
+void __init pv_lock_init(void)
+{
+ if (SHARED_PROCESSOR) {
+ init_hash();
+ __pv_init_lock_hash();
+ pv_lock_op.lock = __pv_lock;
+ pv_lock_op.unlock = __pv_queued_spin_unlock;
+ pv_lock_op.wait = __pv_wait;
+ pv_lock_op.kick = __pv_kick;
+ }
+}
diff --git a/arch/powerpc/lib/locks.c b/arch/powerpc/lib/locks.c
index 892df7d..5daa35a 100644
--- a/arch/powerpc/lib/locks.c
+++ b/arch/powerpc/lib/locks.c
@@ -179,8 +179,12 @@ void queued_spin_unlock_wait(struct qspinlock *lock)
* any unlock is good. And need not _sync, as ->val is set by the SC in
* unlock(), any loads in lock() must see the correct value.
*/
- while (atomic_read(&lock->val) & _Q_LOCKED_MASK)
- cpu_relax();
+ while (atomic_read(&lock->val) & _Q_LOCKED_MASK) {
+ HMT_low();
+ if (SHARED_PROCESSOR)
+ __spin_yield_cpu(spin_lock_holder(lock), 0);
+ }
+ HMT_medium();
done:
smp_mb();
}
diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
index 4ffcaa6..672d888 100644
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -487,6 +487,11 @@ static void __init pSeries_setup_arch(void)
}
ppc_md.pcibios_root_bridge_prepare = pseries_root_bridge_prepare;
+
+#ifdef CONFIG_PARAVIRT_SPINLOCKS
+ pv_lock_init();
+#endif
+
}
static int __init pSeries_init_panel(void)
--
2.4.11
^ permalink raw reply related [flat|nested] 25+ messages in thread
* [PATCH v7 6/6] powerpc: pSeries: Add pv-qspinlock build config/make
2016-09-19 9:23 ` Pan Xinhui
` (7 preceding siblings ...)
(?)
@ 2016-09-19 9:23 ` Pan Xinhui
2016-09-19 8:58 ` kbuild test robot
-1 siblings, 1 reply; 25+ messages in thread
From: Pan Xinhui @ 2016-09-19 9:23 UTC (permalink / raw)
To: linux-kernel, linuxppc-dev
Cc: benh, paulus, mpe, peterz, mingo, paulmck, waiman.long,
xinhui.pan, virtualization
pSeries run as a guest and might need pv-qspinlock.
Signed-off-by: Pan Xinhui <xinhui.pan@linux.vnet.ibm.com>
---
arch/powerpc/kernel/Makefile | 1 +
arch/powerpc/platforms/pseries/Kconfig | 8 ++++++++
2 files changed, 9 insertions(+)
diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile
index fe4c075..efd2f3d 100644
--- a/arch/powerpc/kernel/Makefile
+++ b/arch/powerpc/kernel/Makefile
@@ -49,6 +49,7 @@ obj-$(CONFIG_PPC_970_NAP) += idle_power4.o
obj-$(CONFIG_PPC_P7_NAP) += idle_book3s.o
procfs-y := proc_powerpc.o
obj-$(CONFIG_PROC_FS) += $(procfs-y)
+obj-$(CONFIG_PARAVIRT_SPINLOCKS) += paravirt.o
rtaspci-$(CONFIG_PPC64)-$(CONFIG_PCI) := rtas_pci.o
obj-$(CONFIG_PPC_RTAS) += rtas.o rtas-rtc.o $(rtaspci-y-y)
obj-$(CONFIG_PPC_RTAS_DAEMON) += rtasd.o
diff --git a/arch/powerpc/platforms/pseries/Kconfig b/arch/powerpc/platforms/pseries/Kconfig
index f669323..46632e4 100644
--- a/arch/powerpc/platforms/pseries/Kconfig
+++ b/arch/powerpc/platforms/pseries/Kconfig
@@ -128,3 +128,11 @@ config HV_PERF_CTRS
systems. 24x7 is available on Power 8 systems.
If unsure, select Y.
+
+config PARAVIRT_SPINLOCKS
+ bool "Paravirtialization support for qspinlock"
+ depends on PPC_SPLPAR && QUEUED_SPINLOCKS
+ default y
+ help
+ If platform supports virtualization, for example PowerVM, this option
+ can let guest have a better performace.
--
2.4.11
^ permalink raw reply related [flat|nested] 25+ messages in thread
* [PATCH v7 6/6] powerpc: pSeries: Add pv-qspinlock build config/make
2016-09-19 9:23 ` Pan Xinhui
` (8 preceding siblings ...)
(?)
@ 2016-09-19 9:23 ` Pan Xinhui
-1 siblings, 0 replies; 25+ messages in thread
From: Pan Xinhui @ 2016-09-19 9:23 UTC (permalink / raw)
To: linux-kernel, linuxppc-dev
Cc: xinhui.pan, peterz, benh, waiman.long, virtualization, mingo,
paulus, mpe, paulmck
pSeries run as a guest and might need pv-qspinlock.
Signed-off-by: Pan Xinhui <xinhui.pan@linux.vnet.ibm.com>
---
arch/powerpc/kernel/Makefile | 1 +
arch/powerpc/platforms/pseries/Kconfig | 8 ++++++++
2 files changed, 9 insertions(+)
diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile
index fe4c075..efd2f3d 100644
--- a/arch/powerpc/kernel/Makefile
+++ b/arch/powerpc/kernel/Makefile
@@ -49,6 +49,7 @@ obj-$(CONFIG_PPC_970_NAP) += idle_power4.o
obj-$(CONFIG_PPC_P7_NAP) += idle_book3s.o
procfs-y := proc_powerpc.o
obj-$(CONFIG_PROC_FS) += $(procfs-y)
+obj-$(CONFIG_PARAVIRT_SPINLOCKS) += paravirt.o
rtaspci-$(CONFIG_PPC64)-$(CONFIG_PCI) := rtas_pci.o
obj-$(CONFIG_PPC_RTAS) += rtas.o rtas-rtc.o $(rtaspci-y-y)
obj-$(CONFIG_PPC_RTAS_DAEMON) += rtasd.o
diff --git a/arch/powerpc/platforms/pseries/Kconfig b/arch/powerpc/platforms/pseries/Kconfig
index f669323..46632e4 100644
--- a/arch/powerpc/platforms/pseries/Kconfig
+++ b/arch/powerpc/platforms/pseries/Kconfig
@@ -128,3 +128,11 @@ config HV_PERF_CTRS
systems. 24x7 is available on Power 8 systems.
If unsure, select Y.
+
+config PARAVIRT_SPINLOCKS
+ bool "Paravirtialization support for qspinlock"
+ depends on PPC_SPLPAR && QUEUED_SPINLOCKS
+ default y
+ help
+ If platform supports virtualization, for example PowerVM, this option
+ can let guest have a better performace.
--
2.4.11
^ permalink raw reply related [flat|nested] 25+ messages in thread
* Re: [PATCH v7 6/6] powerpc: pSeries: Add pv-qspinlock build config/make
2016-09-19 8:58 ` kbuild test robot
@ 2016-09-22 5:54 ` xinhui
-1 siblings, 0 replies; 25+ messages in thread
From: xinhui @ 2016-09-22 5:54 UTC (permalink / raw)
To: kbuild test robot
Cc: kbuild-all, linux-kernel, linuxppc-dev, benh, paulus, mpe,
peterz, mingo, paulmck, waiman.long, virtualization
hi, all
ok, this patch set depends on
https://patchwork.kernel.org/patch/8953981/ [V4] powerpc: Implement {cmp}xchg for u8 and u16
sorry.
On 2016年09月19日 16:58, kbuild test robot wrote:
> Hi Pan,
>
> [auto build test ERROR on powerpc/next]
> [also build test ERROR on v4.8-rc7 next-20160916]
> [if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
> [Suggest to use git(>=2.9.0) format-patch --base=<commit> (or --base=auto for convenience) to record what (public, well-known) commit your patch series was built on]
> [Check https://git-scm.com/docs/git-format-patch for more information]
>
> url: https://github.com/0day-ci/linux/commits/Pan-Xinhui/Implement-qspinlock-pv-qspinlock-on-ppc/20160919-133130
> base: https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next
> config: powerpc-allyesconfig (attached as .config)
> compiler: powerpc64-linux-gnu-gcc (Debian 6.1.1-9) 6.1.1 20160705
> reproduce:
> wget https://git.kernel.org/cgit/linux/kernel/git/wfg/lkp-tests.git/plain/sbin/make.cross -O ~/bin/make.cross
> chmod +x ~/bin/make.cross
> # save the attached .config to linux build tree
> make.cross ARCH=powerpc
>
> All errors (new ones prefixed by >>):
>
> include/linux/compiler.h:491:2: note: in expansion of macro '_compiletime_assert'
> _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
> ^~~~~~~~~~~~~~~~~~~
> include/linux/bug.h:51:37: note: in expansion of macro 'compiletime_assert'
> #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
> ^~~~~~~~~~~~~~~~~~
> arch/powerpc/include/asm/cmpxchg.h:326:2: note: in expansion of macro 'BUILD_BUG_ON_MSG'
> BUILD_BUG_ON_MSG(1, "Unsupported size for __cmpxchg");
> ^~~~~~~~~~~~~~~~
> In function '__cmpxchg',
> inlined from 'pv_wait_node' at kernel/locking/qspinlock_paravirt.h:328:3,
> inlined from '__pv_queued_spin_lock_slowpath' at kernel/locking/qspinlock.c:538:3:
> include/linux/compiler.h:491:38: error: call to '__compiletime_assert_326' declared with attribute error: Unsupported size for __cmpxchg
> _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
> ^
> include/linux/compiler.h:474:4: note: in definition of macro '__compiletime_assert'
> prefix ## suffix(); \
> ^~~~~~
> include/linux/compiler.h:491:2: note: in expansion of macro '_compiletime_assert'
> _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
> ^~~~~~~~~~~~~~~~~~~
> include/linux/bug.h:51:37: note: in expansion of macro 'compiletime_assert'
> #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
> ^~~~~~~~~~~~~~~~~~
> arch/powerpc/include/asm/cmpxchg.h:326:2: note: in expansion of macro 'BUILD_BUG_ON_MSG'
> BUILD_BUG_ON_MSG(1, "Unsupported size for __cmpxchg");
> ^~~~~~~~~~~~~~~~
> In function '__cmpxchg',
> inlined from 'pv_wait_head_or_lock' at kernel/locking/qspinlock_paravirt.h:109:10,
> inlined from '__pv_queued_spin_lock_slowpath' at kernel/locking/qspinlock.c:573:5:
> include/linux/compiler.h:491:38: error: call to '__compiletime_assert_326' declared with attribute error: Unsupported size for __cmpxchg
> _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
> ^
> include/linux/compiler.h:474:4: note: in definition of macro '__compiletime_assert'
> prefix ## suffix(); \
> ^~~~~~
> include/linux/compiler.h:491:2: note: in expansion of macro '_compiletime_assert'
> _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
> ^~~~~~~~~~~~~~~~~~~
> include/linux/bug.h:51:37: note: in expansion of macro 'compiletime_assert'
> #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
> ^~~~~~~~~~~~~~~~~~
> arch/powerpc/include/asm/cmpxchg.h:326:2: note: in expansion of macro 'BUILD_BUG_ON_MSG'
> BUILD_BUG_ON_MSG(1, "Unsupported size for __cmpxchg");
> ^~~~~~~~~~~~~~~~
> In function '__xchg_relaxed',
> inlined from 'pv_wait_head_or_lock' at kernel/locking/qspinlock_paravirt.h:442:8,
> inlined from '__pv_queued_spin_lock_slowpath' at kernel/locking/qspinlock.c:573:5:
> include/linux/compiler.h:491:38: error: call to '__compiletime_assert_113' declared with attribute error: Unsupported size for __xchg_local
> _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
> ^
> include/linux/compiler.h:474:4: note: in definition of macro '__compiletime_assert'
> prefix ## suffix(); \
> ^~~~~~
> include/linux/compiler.h:491:2: note: in expansion of macro '_compiletime_assert'
> _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
> ^~~~~~~~~~~~~~~~~~~
> include/linux/bug.h:51:37: note: in expansion of macro 'compiletime_assert'
> #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
> ^~~~~~~~~~~~~~~~~~
> arch/powerpc/include/asm/cmpxchg.h:113:2: note: in expansion of macro 'BUILD_BUG_ON_MSG'
> BUILD_BUG_ON_MSG(1, "Unsupported size for __xchg_local");
> ^~~~~~~~~~~~~~~~
> In function '__cmpxchg',
> inlined from 'pv_kick_node' at kernel/locking/qspinlock_paravirt.h:366:6,
> inlined from '__pv_queued_spin_lock_slowpath' at kernel/locking/qspinlock.c:616:2:
> include/linux/compiler.h:491:38: error: call to '__compiletime_assert_326' declared with attribute error: Unsupported size for __cmpxchg
> _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
> ^
> include/linux/compiler.h:474:4: note: in definition of macro '__compiletime_assert'
> prefix ## suffix(); \
> ^~~~~~
> include/linux/compiler.h:491:2: note: in expansion of macro '_compiletime_assert'
> _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
> ^~~~~~~~~~~~~~~~~~~
> include/linux/bug.h:51:37: note: in expansion of macro 'compiletime_assert'
> #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
> ^~~~~~~~~~~~~~~~~~
> arch/powerpc/include/asm/cmpxchg.h:326:2: note: in expansion of macro 'BUILD_BUG_ON_MSG'
> BUILD_BUG_ON_MSG(1, "Unsupported size for __cmpxchg");
> ^~~~~~~~~~~~~~~~
> In function '__xchg_relaxed',
> inlined from '__pv_queued_spin_lock_slowpath' at kernel/locking/qspinlock.c:184:14:
> include/linux/compiler.h:491:38: error: call to '__compiletime_assert_113' declared with attribute error: Unsupported size for __xchg_local
> _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
> ^
> include/linux/compiler.h:474:4: note: in definition of macro '__compiletime_assert'
> prefix ## suffix(); \
> ^~~~~~
> include/linux/compiler.h:491:2: note: in expansion of macro '_compiletime_assert'
> _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
> ^~~~~~~~~~~~~~~~~~~
> include/linux/bug.h:51:37: note: in expansion of macro 'compiletime_assert'
> #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
> ^~~~~~~~~~~~~~~~~~
> arch/powerpc/include/asm/cmpxchg.h:113:2: note: in expansion of macro 'BUILD_BUG_ON_MSG'
> BUILD_BUG_ON_MSG(1, "Unsupported size for __xchg_local");
> ^~~~~~~~~~~~~~~~
> In function '__cmpxchg_relaxed',
> inlined from '__pv_queued_spin_unlock' at kernel/locking/qspinlock_paravirt.h:547:11:
>>> include/linux/compiler.h:491:38: error: call to '__compiletime_assert_358' declared with attribute error: Unsupported size for __cmpxchg_relaxed
> _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
> ^
> include/linux/compiler.h:474:4: note: in definition of macro '__compiletime_assert'
> prefix ## suffix(); \
> ^~~~~~
> include/linux/compiler.h:491:2: note: in expansion of macro '_compiletime_assert'
> _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
> ^~~~~~~~~~~~~~~~~~~
> include/linux/bug.h:51:37: note: in expansion of macro 'compiletime_assert'
> #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
> ^~~~~~~~~~~~~~~~~~
> arch/powerpc/include/asm/cmpxchg.h:358:2: note: in expansion of macro 'BUILD_BUG_ON_MSG'
> BUILD_BUG_ON_MSG(1, "Unsupported size for __cmpxchg_relaxed");
> ^~~~~~~~~~~~~~~~
>
> vim +/__compiletime_assert_358 +491 include/linux/compiler.h
>
> 9a8ab1c3 Daniel Santos 2013-02-21 475 __compiletime_error_fallback(__cond); \
> 9a8ab1c3 Daniel Santos 2013-02-21 476 } while (0)
> 9a8ab1c3 Daniel Santos 2013-02-21 477
> 9a8ab1c3 Daniel Santos 2013-02-21 478 #define _compiletime_assert(condition, msg, prefix, suffix) \
> 9a8ab1c3 Daniel Santos 2013-02-21 479 __compiletime_assert(condition, msg, prefix, suffix)
> 9a8ab1c3 Daniel Santos 2013-02-21 480
> 9a8ab1c3 Daniel Santos 2013-02-21 481 /**
> 9a8ab1c3 Daniel Santos 2013-02-21 482 * compiletime_assert - break build and emit msg if condition is false
> 9a8ab1c3 Daniel Santos 2013-02-21 483 * @condition: a compile-time constant condition to check
> 9a8ab1c3 Daniel Santos 2013-02-21 484 * @msg: a message to emit if condition is false
> 9a8ab1c3 Daniel Santos 2013-02-21 485 *
> 9a8ab1c3 Daniel Santos 2013-02-21 486 * In tradition of POSIX assert, this macro will break the build if the
> 9a8ab1c3 Daniel Santos 2013-02-21 487 * supplied condition is *false*, emitting the supplied error message if the
> 9a8ab1c3 Daniel Santos 2013-02-21 488 * compiler has support to do so.
> 9a8ab1c3 Daniel Santos 2013-02-21 489 */
> 9a8ab1c3 Daniel Santos 2013-02-21 490 #define compiletime_assert(condition, msg) \
> 9a8ab1c3 Daniel Santos 2013-02-21 @491 _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
> 9a8ab1c3 Daniel Santos 2013-02-21 492
> 47933ad4 Peter Zijlstra 2013-11-06 493 #define compiletime_assert_atomic_type(t) \
> 47933ad4 Peter Zijlstra 2013-11-06 494 compiletime_assert(__native_word(t), \
> 47933ad4 Peter Zijlstra 2013-11-06 495 "Need native word sized stores/loads for atomicity.")
> 47933ad4 Peter Zijlstra 2013-11-06 496
> 9c3cdc1f Linus Torvalds 2008-05-10 497 /*
> 9c3cdc1f Linus Torvalds 2008-05-10 498 * Prevent the compiler from merging or refetching accesses. The compiler
> 9c3cdc1f Linus Torvalds 2008-05-10 499 * is also forbidden from reordering successive instances of ACCESS_ONCE(),
>
> :::::: The code at line 491 was first introduced by commit
> :::::: 9a8ab1c39970a4938a72d94e6fd13be88a797590 bug.h, compiler.h: introduce compiletime_assert & BUILD_BUG_ON_MSG
>
> :::::: TO: Daniel Santos <daniel.santos@pobox.com>
> :::::: CC: Linus Torvalds <torvalds@linux-foundation.org>
>
> ---
> 0-DAY kernel test infrastructure Open Source Technology Center
> https://lists.01.org/pipermail/kbuild-all Intel Corporation
>
^ permalink raw reply [flat|nested] 25+ messages in thread
* Re: [PATCH v7 6/6] powerpc: pSeries: Add pv-qspinlock build config/make
@ 2016-09-22 5:54 ` xinhui
0 siblings, 0 replies; 25+ messages in thread
From: xinhui @ 2016-09-22 5:54 UTC (permalink / raw)
To: kbuild test robot
Cc: peterz, mpe, linux-kernel, waiman.long, virtualization, mingo,
paulus, kbuild-all, benh, paulmck, linuxppc-dev
hi, all
ok, this patch set depends on
https://patchwork.kernel.org/patch/8953981/ [V4] powerpc: Implement {cmp}xchg for u8 and u16
sorry.
On 2016年09月19日 16:58, kbuild test robot wrote:
> Hi Pan,
>
> [auto build test ERROR on powerpc/next]
> [also build test ERROR on v4.8-rc7 next-20160916]
> [if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
> [Suggest to use git(>=2.9.0) format-patch --base=<commit> (or --base=auto for convenience) to record what (public, well-known) commit your patch series was built on]
> [Check https://git-scm.com/docs/git-format-patch for more information]
>
> url: https://github.com/0day-ci/linux/commits/Pan-Xinhui/Implement-qspinlock-pv-qspinlock-on-ppc/20160919-133130
> base: https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next
> config: powerpc-allyesconfig (attached as .config)
> compiler: powerpc64-linux-gnu-gcc (Debian 6.1.1-9) 6.1.1 20160705
> reproduce:
> wget https://git.kernel.org/cgit/linux/kernel/git/wfg/lkp-tests.git/plain/sbin/make.cross -O ~/bin/make.cross
> chmod +x ~/bin/make.cross
> # save the attached .config to linux build tree
> make.cross ARCH=powerpc
>
> All errors (new ones prefixed by >>):
>
> include/linux/compiler.h:491:2: note: in expansion of macro '_compiletime_assert'
> _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
> ^~~~~~~~~~~~~~~~~~~
> include/linux/bug.h:51:37: note: in expansion of macro 'compiletime_assert'
> #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
> ^~~~~~~~~~~~~~~~~~
> arch/powerpc/include/asm/cmpxchg.h:326:2: note: in expansion of macro 'BUILD_BUG_ON_MSG'
> BUILD_BUG_ON_MSG(1, "Unsupported size for __cmpxchg");
> ^~~~~~~~~~~~~~~~
> In function '__cmpxchg',
> inlined from 'pv_wait_node' at kernel/locking/qspinlock_paravirt.h:328:3,
> inlined from '__pv_queued_spin_lock_slowpath' at kernel/locking/qspinlock.c:538:3:
> include/linux/compiler.h:491:38: error: call to '__compiletime_assert_326' declared with attribute error: Unsupported size for __cmpxchg
> _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
> ^
> include/linux/compiler.h:474:4: note: in definition of macro '__compiletime_assert'
> prefix ## suffix(); \
> ^~~~~~
> include/linux/compiler.h:491:2: note: in expansion of macro '_compiletime_assert'
> _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
> ^~~~~~~~~~~~~~~~~~~
> include/linux/bug.h:51:37: note: in expansion of macro 'compiletime_assert'
> #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
> ^~~~~~~~~~~~~~~~~~
> arch/powerpc/include/asm/cmpxchg.h:326:2: note: in expansion of macro 'BUILD_BUG_ON_MSG'
> BUILD_BUG_ON_MSG(1, "Unsupported size for __cmpxchg");
> ^~~~~~~~~~~~~~~~
> In function '__cmpxchg',
> inlined from 'pv_wait_head_or_lock' at kernel/locking/qspinlock_paravirt.h:109:10,
> inlined from '__pv_queued_spin_lock_slowpath' at kernel/locking/qspinlock.c:573:5:
> include/linux/compiler.h:491:38: error: call to '__compiletime_assert_326' declared with attribute error: Unsupported size for __cmpxchg
> _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
> ^
> include/linux/compiler.h:474:4: note: in definition of macro '__compiletime_assert'
> prefix ## suffix(); \
> ^~~~~~
> include/linux/compiler.h:491:2: note: in expansion of macro '_compiletime_assert'
> _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
> ^~~~~~~~~~~~~~~~~~~
> include/linux/bug.h:51:37: note: in expansion of macro 'compiletime_assert'
> #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
> ^~~~~~~~~~~~~~~~~~
> arch/powerpc/include/asm/cmpxchg.h:326:2: note: in expansion of macro 'BUILD_BUG_ON_MSG'
> BUILD_BUG_ON_MSG(1, "Unsupported size for __cmpxchg");
> ^~~~~~~~~~~~~~~~
> In function '__xchg_relaxed',
> inlined from 'pv_wait_head_or_lock' at kernel/locking/qspinlock_paravirt.h:442:8,
> inlined from '__pv_queued_spin_lock_slowpath' at kernel/locking/qspinlock.c:573:5:
> include/linux/compiler.h:491:38: error: call to '__compiletime_assert_113' declared with attribute error: Unsupported size for __xchg_local
> _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
> ^
> include/linux/compiler.h:474:4: note: in definition of macro '__compiletime_assert'
> prefix ## suffix(); \
> ^~~~~~
> include/linux/compiler.h:491:2: note: in expansion of macro '_compiletime_assert'
> _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
> ^~~~~~~~~~~~~~~~~~~
> include/linux/bug.h:51:37: note: in expansion of macro 'compiletime_assert'
> #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
> ^~~~~~~~~~~~~~~~~~
> arch/powerpc/include/asm/cmpxchg.h:113:2: note: in expansion of macro 'BUILD_BUG_ON_MSG'
> BUILD_BUG_ON_MSG(1, "Unsupported size for __xchg_local");
> ^~~~~~~~~~~~~~~~
> In function '__cmpxchg',
> inlined from 'pv_kick_node' at kernel/locking/qspinlock_paravirt.h:366:6,
> inlined from '__pv_queued_spin_lock_slowpath' at kernel/locking/qspinlock.c:616:2:
> include/linux/compiler.h:491:38: error: call to '__compiletime_assert_326' declared with attribute error: Unsupported size for __cmpxchg
> _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
> ^
> include/linux/compiler.h:474:4: note: in definition of macro '__compiletime_assert'
> prefix ## suffix(); \
> ^~~~~~
> include/linux/compiler.h:491:2: note: in expansion of macro '_compiletime_assert'
> _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
> ^~~~~~~~~~~~~~~~~~~
> include/linux/bug.h:51:37: note: in expansion of macro 'compiletime_assert'
> #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
> ^~~~~~~~~~~~~~~~~~
> arch/powerpc/include/asm/cmpxchg.h:326:2: note: in expansion of macro 'BUILD_BUG_ON_MSG'
> BUILD_BUG_ON_MSG(1, "Unsupported size for __cmpxchg");
> ^~~~~~~~~~~~~~~~
> In function '__xchg_relaxed',
> inlined from '__pv_queued_spin_lock_slowpath' at kernel/locking/qspinlock.c:184:14:
> include/linux/compiler.h:491:38: error: call to '__compiletime_assert_113' declared with attribute error: Unsupported size for __xchg_local
> _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
> ^
> include/linux/compiler.h:474:4: note: in definition of macro '__compiletime_assert'
> prefix ## suffix(); \
> ^~~~~~
> include/linux/compiler.h:491:2: note: in expansion of macro '_compiletime_assert'
> _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
> ^~~~~~~~~~~~~~~~~~~
> include/linux/bug.h:51:37: note: in expansion of macro 'compiletime_assert'
> #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
> ^~~~~~~~~~~~~~~~~~
> arch/powerpc/include/asm/cmpxchg.h:113:2: note: in expansion of macro 'BUILD_BUG_ON_MSG'
> BUILD_BUG_ON_MSG(1, "Unsupported size for __xchg_local");
> ^~~~~~~~~~~~~~~~
> In function '__cmpxchg_relaxed',
> inlined from '__pv_queued_spin_unlock' at kernel/locking/qspinlock_paravirt.h:547:11:
>>> include/linux/compiler.h:491:38: error: call to '__compiletime_assert_358' declared with attribute error: Unsupported size for __cmpxchg_relaxed
> _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
> ^
> include/linux/compiler.h:474:4: note: in definition of macro '__compiletime_assert'
> prefix ## suffix(); \
> ^~~~~~
> include/linux/compiler.h:491:2: note: in expansion of macro '_compiletime_assert'
> _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
> ^~~~~~~~~~~~~~~~~~~
> include/linux/bug.h:51:37: note: in expansion of macro 'compiletime_assert'
> #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
> ^~~~~~~~~~~~~~~~~~
> arch/powerpc/include/asm/cmpxchg.h:358:2: note: in expansion of macro 'BUILD_BUG_ON_MSG'
> BUILD_BUG_ON_MSG(1, "Unsupported size for __cmpxchg_relaxed");
> ^~~~~~~~~~~~~~~~
>
> vim +/__compiletime_assert_358 +491 include/linux/compiler.h
>
> 9a8ab1c3 Daniel Santos 2013-02-21 475 __compiletime_error_fallback(__cond); \
> 9a8ab1c3 Daniel Santos 2013-02-21 476 } while (0)
> 9a8ab1c3 Daniel Santos 2013-02-21 477
> 9a8ab1c3 Daniel Santos 2013-02-21 478 #define _compiletime_assert(condition, msg, prefix, suffix) \
> 9a8ab1c3 Daniel Santos 2013-02-21 479 __compiletime_assert(condition, msg, prefix, suffix)
> 9a8ab1c3 Daniel Santos 2013-02-21 480
> 9a8ab1c3 Daniel Santos 2013-02-21 481 /**
> 9a8ab1c3 Daniel Santos 2013-02-21 482 * compiletime_assert - break build and emit msg if condition is false
> 9a8ab1c3 Daniel Santos 2013-02-21 483 * @condition: a compile-time constant condition to check
> 9a8ab1c3 Daniel Santos 2013-02-21 484 * @msg: a message to emit if condition is false
> 9a8ab1c3 Daniel Santos 2013-02-21 485 *
> 9a8ab1c3 Daniel Santos 2013-02-21 486 * In tradition of POSIX assert, this macro will break the build if the
> 9a8ab1c3 Daniel Santos 2013-02-21 487 * supplied condition is *false*, emitting the supplied error message if the
> 9a8ab1c3 Daniel Santos 2013-02-21 488 * compiler has support to do so.
> 9a8ab1c3 Daniel Santos 2013-02-21 489 */
> 9a8ab1c3 Daniel Santos 2013-02-21 490 #define compiletime_assert(condition, msg) \
> 9a8ab1c3 Daniel Santos 2013-02-21 @491 _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
> 9a8ab1c3 Daniel Santos 2013-02-21 492
> 47933ad4 Peter Zijlstra 2013-11-06 493 #define compiletime_assert_atomic_type(t) \
> 47933ad4 Peter Zijlstra 2013-11-06 494 compiletime_assert(__native_word(t), \
> 47933ad4 Peter Zijlstra 2013-11-06 495 "Need native word sized stores/loads for atomicity.")
> 47933ad4 Peter Zijlstra 2013-11-06 496
> 9c3cdc1f Linus Torvalds 2008-05-10 497 /*
> 9c3cdc1f Linus Torvalds 2008-05-10 498 * Prevent the compiler from merging or refetching accesses. The compiler
> 9c3cdc1f Linus Torvalds 2008-05-10 499 * is also forbidden from reordering successive instances of ACCESS_ONCE(),
>
> :::::: The code at line 491 was first introduced by commit
> :::::: 9a8ab1c39970a4938a72d94e6fd13be88a797590 bug.h, compiler.h: introduce compiletime_assert & BUILD_BUG_ON_MSG
>
> :::::: TO: Daniel Santos <daniel.santos@pobox.com>
> :::::: CC: Linus Torvalds <torvalds@linux-foundation.org>
>
> ---
> 0-DAY kernel test infrastructure Open Source Technology Center
> https://lists.01.org/pipermail/kbuild-all Intel Corporation
>
_______________________________________________
Virtualization mailing list
Virtualization@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/virtualization
^ permalink raw reply [flat|nested] 25+ messages in thread
* Re: [PATCH v7 6/6] powerpc: pSeries: Add pv-qspinlock build config/make
2016-09-22 5:54 ` xinhui
(?)
(?)
@ 2016-09-22 10:31 ` Michael Ellerman
-1 siblings, 0 replies; 25+ messages in thread
From: Michael Ellerman @ 2016-09-22 10:31 UTC (permalink / raw)
To: xinhui, kbuild test robot
Cc: kbuild-all, linux-kernel, linuxppc-dev, benh, paulus, peterz,
mingo, paulmck, waiman.long, virtualization
xinhui <xinhui.pan@linux.vnet.ibm.com> writes:
> hi, all
> ok, this patch set depends on
> https://patchwork.kernel.org/patch/8953981/ [V4] powerpc: Implement {cmp}xchg for u8 and u16
AKA: https://patchwork.ozlabs.org/patch/615480/
Sorry I saw the discussion on that and thought there'd be a new version.
But now I read the whole thread it looks like it was OK in the end.
I'll try and get it merged.
cheers
^ permalink raw reply [flat|nested] 25+ messages in thread
* Re: [PATCH v7 6/6] powerpc: pSeries: Add pv-qspinlock build config/make
2016-09-22 5:54 ` xinhui
(?)
@ 2016-09-22 10:31 ` Michael Ellerman
-1 siblings, 0 replies; 25+ messages in thread
From: Michael Ellerman @ 2016-09-22 10:31 UTC (permalink / raw)
To: xinhui, kbuild test robot
Cc: peterz, benh, linux-kernel, waiman.long, virtualization, mingo,
paulus, kbuild-all, paulmck, linuxppc-dev
xinhui <xinhui.pan@linux.vnet.ibm.com> writes:
> hi, all
> ok, this patch set depends on
> https://patchwork.kernel.org/patch/8953981/ [V4] powerpc: Implement {cmp}xchg for u8 and u16
AKA: https://patchwork.ozlabs.org/patch/615480/
Sorry I saw the discussion on that and thought there'd be a new version.
But now I read the whole thread it looks like it was OK in the end.
I'll try and get it merged.
cheers
^ permalink raw reply [flat|nested] 25+ messages in thread
* [tip:locking/core] locking/pv-qspinlock: Use cmpxchg_release() in __pv_queued_spin_unlock()
2016-09-19 9:23 ` Pan Xinhui
(?)
@ 2016-09-22 14:02 ` tip-bot for Pan Xinhui
-1 siblings, 0 replies; 25+ messages in thread
From: tip-bot for Pan Xinhui @ 2016-09-22 14:02 UTC (permalink / raw)
To: linux-tip-commits
Cc: torvalds, xinhui.pan, tglx, mingo, hpa, boqun.feng, linux-kernel, peterz
Commit-ID: b193049375b04df3ada8c3347b7083db95918bc3
Gitweb: http://git.kernel.org/tip/b193049375b04df3ada8c3347b7083db95918bc3
Author: Pan Xinhui <xinhui.pan@linux.vnet.ibm.com>
AuthorDate: Mon, 19 Sep 2016 05:23:52 -0400
Committer: Ingo Molnar <mingo@kernel.org>
CommitDate: Thu, 22 Sep 2016 15:25:51 +0200
locking/pv-qspinlock: Use cmpxchg_release() in __pv_queued_spin_unlock()
cmpxchg_release() is more lighweight than cmpxchg() on some archs(e.g.
PPC), moreover, in __pv_queued_spin_unlock() we only needs a RELEASE in
the fast path(pairing with *_try_lock() or *_lock()). And the slow path
has smp_store_release too. So it's safe to use cmpxchg_release here.
Suggested-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Pan Xinhui <xinhui.pan@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: benh@kernel.crashing.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: mpe@ellerman.id.au
Cc: paulmck@linux.vnet.ibm.com
Cc: paulus@samba.org
Cc: virtualization@lists.linux-foundation.org
Cc: waiman.long@hpe.com
Link: http://lkml.kernel.org/r/1474277037-15200-2-git-send-email-xinhui.pan@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
kernel/locking/qspinlock_paravirt.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/kernel/locking/qspinlock_paravirt.h b/kernel/locking/qspinlock_paravirt.h
index 3acf16d..e3b5520 100644
--- a/kernel/locking/qspinlock_paravirt.h
+++ b/kernel/locking/qspinlock_paravirt.h
@@ -540,7 +540,7 @@ __visible void __pv_queued_spin_unlock(struct qspinlock *lock)
* unhash. Otherwise it would be possible to have multiple @lock
* entries, which would be BAD.
*/
- locked = cmpxchg(&l->locked, _Q_LOCKED_VAL, 0);
+ locked = cmpxchg_release(&l->locked, _Q_LOCKED_VAL, 0);
if (likely(locked == _Q_LOCKED_VAL))
return;
^ permalink raw reply related [flat|nested] 25+ messages in thread
* Re: [PATCH v7 4/6] powerpc: lib/locks.c: Add cpu yield/wake helper function
2016-09-19 9:23 ` [PATCH v7 4/6] powerpc: lib/locks.c: Add cpu yield/wake helper function Pan Xinhui
@ 2016-09-22 15:17 ` Boqun Feng
0 siblings, 0 replies; 25+ messages in thread
From: Boqun Feng @ 2016-09-22 15:17 UTC (permalink / raw)
To: Pan Xinhui
Cc: linux-kernel, linuxppc-dev, benh, paulus, mpe, peterz, mingo,
paulmck, waiman.long, virtualization
[-- Attachment #1: Type: text/plain, Size: 4005 bytes --]
Hi Xinhui,
On Mon, Sep 19, 2016 at 05:23:55AM -0400, Pan Xinhui wrote:
> Add two corresponding helper functions to support pv-qspinlock.
>
> For normal use, __spin_yield_cpu will confer current vcpu slices to the
> target vcpu(say, a lock holder). If target vcpu is not specified or it
> is in running state, such conferging to lpar happens or not depends.
>
> Because hcall itself will introduce latency and a little overhead. And
> we do NOT want to suffer any latency on some cases, e.g. in interrupt handler.
> The second parameter *confer* can indicate such case.
>
> __spin_wake_cpu is simpiler, it will wake up one vcpu regardless of its
> current vcpu state.
>
> Signed-off-by: Pan Xinhui <xinhui.pan@linux.vnet.ibm.com>
> ---
> arch/powerpc/include/asm/spinlock.h | 4 +++
> arch/powerpc/lib/locks.c | 59 +++++++++++++++++++++++++++++++++++++
> 2 files changed, 63 insertions(+)
>
> diff --git a/arch/powerpc/include/asm/spinlock.h b/arch/powerpc/include/asm/spinlock.h
> index 6aef8dd..abb6b0f 100644
> --- a/arch/powerpc/include/asm/spinlock.h
> +++ b/arch/powerpc/include/asm/spinlock.h
> @@ -56,9 +56,13 @@
> /* We only yield to the hypervisor if we are in shared processor mode */
> #define SHARED_PROCESSOR (lppaca_shared_proc(local_paca->lppaca_ptr))
> extern void __spin_yield(arch_spinlock_t *lock);
> +extern void __spin_yield_cpu(int cpu, int confer);
> +extern void __spin_wake_cpu(int cpu);
> extern void __rw_yield(arch_rwlock_t *lock);
> #else /* SPLPAR */
> #define __spin_yield(x) barrier()
> +#define __spin_yield_cpu(x,y) barrier()
> +#define __spin_wake_cpu(x) barrier()
> #define __rw_yield(x) barrier()
> #define SHARED_PROCESSOR 0
> #endif
> diff --git a/arch/powerpc/lib/locks.c b/arch/powerpc/lib/locks.c
> index 6574626..892df7d 100644
> --- a/arch/powerpc/lib/locks.c
> +++ b/arch/powerpc/lib/locks.c
> @@ -23,6 +23,65 @@
> #include <asm/hvcall.h>
> #include <asm/smp.h>
>
> +/*
> + * confer our slices to a specified cpu and return. If it is already running or
> + * cpu is -1, then we will check confer. If confer is NULL, we will return
> + * otherwise we confer our slices to lpar.
> + */
> +void __spin_yield_cpu(int cpu, int confer)
> +{
> + unsigned int holder_cpu = cpu, yield_count;
> +
You don't need @holder_cpu at all, do you?
> + if (cpu == -1)
> + goto yield_to_lpar;
> +
> + BUG_ON(holder_cpu >= nr_cpu_ids);
> + yield_count = be32_to_cpu(lppaca_of(holder_cpu).yield_count);
> +
> + /* if cpu is running, confer slices to lpar conditionally*/
> + if ((yield_count & 1) == 0)
> + goto yield_to_lpar;
> +
> + plpar_hcall_norets(H_CONFER,
> + get_hard_smp_processor_id(holder_cpu), yield_count);
> + return;
> +
> +yield_to_lpar:
> + if (confer)
> + plpar_hcall_norets(H_CONFER, -1, 0);
> +}
> +EXPORT_SYMBOL_GPL(__spin_yield_cpu);
> +
> +void __spin_wake_cpu(int cpu)
> +{
> + unsigned int holder_cpu = cpu;
> +
Ditto.
Regards,
Boqun
> + BUG_ON(holder_cpu >= nr_cpu_ids);
> + /*
> + * NOTE: we should always do this hcall regardless of
> + * the yield_count of the holder_cpu.
> + * as thers might be a case like below;
> + * CPU 1 2
> + * yielded = true
> + * if (yielded)
> + * __spin_wake_cpu()
> + * __spin_yield_cpu()
> + *
> + * So we might lose a wake if we check the yield_count and
> + * return directly if the holder_cpu is running.
> + * IOW. do NOT code like below.
> + * yield_count = be32_to_cpu(lppaca_of(holder_cpu).yield_count);
> + * if ((yield_count & 1) == 0)
> + * return;
> + *
> + * a PROD hcall marks the target_cpu proded, which cause the next cede or confer
> + * called on the target_cpu invalid.
> + */
> + plpar_hcall_norets(H_PROD,
> + get_hard_smp_processor_id(holder_cpu));
> +}
> +EXPORT_SYMBOL_GPL(__spin_wake_cpu);
> +
> #ifndef CONFIG_QUEUED_SPINLOCKS
> void __spin_yield(arch_spinlock_t *lock)
> {
> --
> 2.4.11
>
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^ permalink raw reply [flat|nested] 25+ messages in thread
* Re: [PATCH v7 4/6] powerpc: lib/locks.c: Add cpu yield/wake helper function
@ 2016-09-22 15:17 ` Boqun Feng
0 siblings, 0 replies; 25+ messages in thread
From: Boqun Feng @ 2016-09-22 15:17 UTC (permalink / raw)
To: Pan Xinhui
Cc: peterz, benh, linux-kernel, waiman.long, virtualization, mingo,
paulus, mpe, paulmck, linuxppc-dev
[-- Attachment #1.1: Type: text/plain, Size: 4005 bytes --]
Hi Xinhui,
On Mon, Sep 19, 2016 at 05:23:55AM -0400, Pan Xinhui wrote:
> Add two corresponding helper functions to support pv-qspinlock.
>
> For normal use, __spin_yield_cpu will confer current vcpu slices to the
> target vcpu(say, a lock holder). If target vcpu is not specified or it
> is in running state, such conferging to lpar happens or not depends.
>
> Because hcall itself will introduce latency and a little overhead. And
> we do NOT want to suffer any latency on some cases, e.g. in interrupt handler.
> The second parameter *confer* can indicate such case.
>
> __spin_wake_cpu is simpiler, it will wake up one vcpu regardless of its
> current vcpu state.
>
> Signed-off-by: Pan Xinhui <xinhui.pan@linux.vnet.ibm.com>
> ---
> arch/powerpc/include/asm/spinlock.h | 4 +++
> arch/powerpc/lib/locks.c | 59 +++++++++++++++++++++++++++++++++++++
> 2 files changed, 63 insertions(+)
>
> diff --git a/arch/powerpc/include/asm/spinlock.h b/arch/powerpc/include/asm/spinlock.h
> index 6aef8dd..abb6b0f 100644
> --- a/arch/powerpc/include/asm/spinlock.h
> +++ b/arch/powerpc/include/asm/spinlock.h
> @@ -56,9 +56,13 @@
> /* We only yield to the hypervisor if we are in shared processor mode */
> #define SHARED_PROCESSOR (lppaca_shared_proc(local_paca->lppaca_ptr))
> extern void __spin_yield(arch_spinlock_t *lock);
> +extern void __spin_yield_cpu(int cpu, int confer);
> +extern void __spin_wake_cpu(int cpu);
> extern void __rw_yield(arch_rwlock_t *lock);
> #else /* SPLPAR */
> #define __spin_yield(x) barrier()
> +#define __spin_yield_cpu(x,y) barrier()
> +#define __spin_wake_cpu(x) barrier()
> #define __rw_yield(x) barrier()
> #define SHARED_PROCESSOR 0
> #endif
> diff --git a/arch/powerpc/lib/locks.c b/arch/powerpc/lib/locks.c
> index 6574626..892df7d 100644
> --- a/arch/powerpc/lib/locks.c
> +++ b/arch/powerpc/lib/locks.c
> @@ -23,6 +23,65 @@
> #include <asm/hvcall.h>
> #include <asm/smp.h>
>
> +/*
> + * confer our slices to a specified cpu and return. If it is already running or
> + * cpu is -1, then we will check confer. If confer is NULL, we will return
> + * otherwise we confer our slices to lpar.
> + */
> +void __spin_yield_cpu(int cpu, int confer)
> +{
> + unsigned int holder_cpu = cpu, yield_count;
> +
You don't need @holder_cpu at all, do you?
> + if (cpu == -1)
> + goto yield_to_lpar;
> +
> + BUG_ON(holder_cpu >= nr_cpu_ids);
> + yield_count = be32_to_cpu(lppaca_of(holder_cpu).yield_count);
> +
> + /* if cpu is running, confer slices to lpar conditionally*/
> + if ((yield_count & 1) == 0)
> + goto yield_to_lpar;
> +
> + plpar_hcall_norets(H_CONFER,
> + get_hard_smp_processor_id(holder_cpu), yield_count);
> + return;
> +
> +yield_to_lpar:
> + if (confer)
> + plpar_hcall_norets(H_CONFER, -1, 0);
> +}
> +EXPORT_SYMBOL_GPL(__spin_yield_cpu);
> +
> +void __spin_wake_cpu(int cpu)
> +{
> + unsigned int holder_cpu = cpu;
> +
Ditto.
Regards,
Boqun
> + BUG_ON(holder_cpu >= nr_cpu_ids);
> + /*
> + * NOTE: we should always do this hcall regardless of
> + * the yield_count of the holder_cpu.
> + * as thers might be a case like below;
> + * CPU 1 2
> + * yielded = true
> + * if (yielded)
> + * __spin_wake_cpu()
> + * __spin_yield_cpu()
> + *
> + * So we might lose a wake if we check the yield_count and
> + * return directly if the holder_cpu is running.
> + * IOW. do NOT code like below.
> + * yield_count = be32_to_cpu(lppaca_of(holder_cpu).yield_count);
> + * if ((yield_count & 1) == 0)
> + * return;
> + *
> + * a PROD hcall marks the target_cpu proded, which cause the next cede or confer
> + * called on the target_cpu invalid.
> + */
> + plpar_hcall_norets(H_PROD,
> + get_hard_smp_processor_id(holder_cpu));
> +}
> +EXPORT_SYMBOL_GPL(__spin_wake_cpu);
> +
> #ifndef CONFIG_QUEUED_SPINLOCKS
> void __spin_yield(arch_spinlock_t *lock)
> {
> --
> 2.4.11
>
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^ permalink raw reply [flat|nested] 25+ messages in thread
end of thread, other threads:[~2016-09-22 15:17 UTC | newest]
Thread overview: 25+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2016-09-19 9:23 [PATCH v7 0/6] Implement qspinlock/pv-qspinlock on ppc Pan Xinhui
2016-09-19 9:23 ` Pan Xinhui
2016-09-19 9:23 ` [PATCH v7 1/6] pv-qspinlock: use cmpxchg_release in __pv_queued_spin_unlock Pan Xinhui
2016-09-19 9:23 ` Pan Xinhui
2016-09-22 14:02 ` [tip:locking/core] locking/pv-qspinlock: Use cmpxchg_release() in __pv_queued_spin_unlock() tip-bot for Pan Xinhui
2016-09-19 9:23 ` [PATCH v7 2/6] powerpc/qspinlock: powerpc support qspinlock Pan Xinhui
2016-09-19 9:23 ` Pan Xinhui
2016-09-19 9:23 ` [PATCH v7 3/6] powerpc: pseries/Kconfig: Add qspinlock build config Pan Xinhui
2016-09-19 9:23 ` Pan Xinhui
2016-09-19 8:40 ` kbuild test robot
2016-09-19 8:40 ` kbuild test robot
2016-09-19 9:23 ` [PATCH v7 4/6] powerpc: lib/locks.c: Add cpu yield/wake helper function Pan Xinhui
2016-09-22 15:17 ` Boqun Feng
2016-09-22 15:17 ` Boqun Feng
2016-09-19 9:23 ` Pan Xinhui
2016-09-19 9:23 ` [PATCH v7 5/6] powerpc/pv-qspinlock: powerpc support pv-qspinlock Pan Xinhui
2016-09-19 9:23 ` Pan Xinhui
2016-09-19 9:23 ` [PATCH v7 6/6] powerpc: pSeries: Add pv-qspinlock build config/make Pan Xinhui
2016-09-19 8:58 ` kbuild test robot
2016-09-19 8:58 ` kbuild test robot
2016-09-22 5:54 ` xinhui
2016-09-22 5:54 ` xinhui
2016-09-22 10:31 ` Michael Ellerman
2016-09-22 10:31 ` Michael Ellerman
2016-09-19 9:23 ` Pan Xinhui
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