search for: call_rwsem_down_write_fail

It was found when running fio sequential write test with a XFS ramdisk on a VM running on a 2-socket x86-64 system, the %CPU times as reported by perf were as follows: 69.75% 0.59% fio [k] down_write 69.15% 0.01% fio [k] call_rwsem_down_write_failed 67.12% 1.12% fio [k] rwsem_down_write_failed 63.48% 52.77% fio [k] osq_lock 9.46% 7.88% fio [k] __raw_callee_save___kvm_vcpu_is_preempt 3.93% 3.93% fio [k] __kvm_vcpu_is_preempted Making vcpu_is_preempted() a callee-save function has a relatively high cost on x86-64 primarily du...

It was found when running fio sequential write test with a XFS ramdisk on a VM running on a 2-socket x86-64 system, the %CPU times as reported by perf were as follows: 69.75% 0.59% fio [k] down_write 69.15% 0.01% fio [k] call_rwsem_down_write_failed 67.12% 1.12% fio [k] rwsem_down_write_failed 63.48% 52.77% fio [k] osq_lock 9.46% 7.88% fio [k] __raw_callee_save___kvm_vcpu_is_preempt 3.93% 3.93% fio [k] __kvm_vcpu_is_preempted Making vcpu_is_preempted() a callee-save function has a relatively high cost on x86-64 primarily du...

It was found when running fio sequential write test with a XFS ramdisk on a 2-socket x86-64 system, the %CPU times as reported by perf were as follows: 71.27% 0.28% fio [k] down_write 70.99% 0.01% fio [k] call_rwsem_down_write_failed 69.43% 1.18% fio [k] rwsem_down_write_failed 65.51% 54.57% fio [k] osq_lock 9.72% 7.99% fio [k] __raw_callee_save___kvm_vcpu_is_preempted 4.16% 4.16% fio [k] __kvm_vcpu_is_preempted So making vcpu_is_preempted() a callee-save function has a pretty high cost associated with it. A...

It was found when running fio sequential write test with a XFS ramdisk on a 2-socket x86-64 system, the %CPU times as reported by perf were as follows: 71.27% 0.28% fio [k] down_write 70.99% 0.01% fio [k] call_rwsem_down_write_failed 69.43% 1.18% fio [k] rwsem_down_write_failed 65.51% 54.57% fio [k] osq_lock 9.72% 7.99% fio [k] __raw_callee_save___kvm_vcpu_is_preempted 4.16% 4.16% fio [k] __kvm_vcpu_is_preempted So making vcpu_is_preempted() a callee-save function has a pretty high cost associated with it. A...

It was found when running fio sequential write test with a XFS ramdisk on a KVM guest running on a 2-socket x86-64 system, the %CPU times as reported by perf were as follows: 69.75% 0.59% fio [k] down_write 69.15% 0.01% fio [k] call_rwsem_down_write_failed 67.12% 1.12% fio [k] rwsem_down_write_failed 63.48% 52.77% fio [k] osq_lock 9.46% 7.88% fio [k] __raw_callee_save___kvm_vcpu_is_preempt 3.93% 3.93% fio [k] __kvm_vcpu_is_preempted Making vcpu_is_preempted() a callee-save function has a relatively high cost on x86-64 primarily du...

It was found when running fio sequential write test with a XFS ramdisk on a KVM guest running on a 2-socket x86-64 system, the %CPU times as reported by perf were as follows: 69.75% 0.59% fio [k] down_write 69.15% 0.01% fio [k] call_rwsem_down_write_failed 67.12% 1.12% fio [k] rwsem_down_write_failed 63.48% 52.77% fio [k] osq_lock 9.46% 7.88% fio [k] __raw_callee_save___kvm_vcpu_is_preempt 3.93% 3.93% fio [k] __kvm_vcpu_is_preempted Making vcpu_is_preempted() a callee-save function has a relatively high cost on x86-64 primarily du...

...iman Long wrote: >> It was found when running fio sequential write test with a XFS ramdisk >> on a VM running on a 2-socket x86-64 system, the %CPU times as reported >> by perf were as follows: >> >> 69.75% 0.59% fio [k] down_write >> 69.15% 0.01% fio [k] call_rwsem_down_write_failed >> 67.12% 1.12% fio [k] rwsem_down_write_failed >> 63.48% 52.77% fio [k] osq_lock >> 9.46% 7.88% fio [k] __raw_callee_save___kvm_vcpu_is_preempt >> 3.93% 3.93% fio [k] __kvm_vcpu_is_preempted >> > Thinking about this again, wouldn't something...

...iman Long wrote: >> It was found when running fio sequential write test with a XFS ramdisk >> on a VM running on a 2-socket x86-64 system, the %CPU times as reported >> by perf were as follows: >> >> 69.75% 0.59% fio [k] down_write >> 69.15% 0.01% fio [k] call_rwsem_down_write_failed >> 67.12% 1.12% fio [k] rwsem_down_write_failed >> 63.48% 52.77% fio [k] osq_lock >> 9.46% 7.88% fio [k] __raw_callee_save___kvm_vcpu_is_preempt >> 3.93% 3.93% fio [k] __kvm_vcpu_is_preempted >> > Thinking about this again, wouldn't something...

v3->v4: - Fix x86-32 build error. v2->v3: - Provide an optimized __raw_callee_save___kvm_vcpu_is_preempted() in assembly as suggested by PeterZ. - Add a new patch to change vcpu_is_preempted() argument type to long to ease the writing of the assembly code. v1->v2: - Rerun the fio test on a different system on both bare-metal and a KVM guest. Both sockets were

v3->v4: - Fix x86-32 build error. v2->v3: - Provide an optimized __raw_callee_save___kvm_vcpu_is_preempted() in assembly as suggested by PeterZ. - Add a new patch to change vcpu_is_preempted() argument type to long to ease the writing of the assembly code. v1->v2: - Rerun the fio test on a different system on both bare-metal and a KVM guest. Both sockets were

v2->v3: - Provide an optimized __raw_callee_save___kvm_vcpu_is_preempted() in assembly as suggested by PeterZ. - Add a new patch to change vcpu_is_preempted() argument type to long to ease the writing of the assembly code. v1->v2: - Rerun the fio test on a different system on both bare-metal and a KVM guest. Both sockets were utilized in this test. - The commit log was

v2->v3: - Provide an optimized __raw_callee_save___kvm_vcpu_is_preempted() in assembly as suggested by PeterZ. - Add a new patch to change vcpu_is_preempted() argument type to long to ease the writing of the assembly code. v1->v2: - Rerun the fio test on a different system on both bare-metal and a KVM guest. Both sockets were utilized in this test. - The commit log was

...d, Feb 08, 2017 at 01:00:24PM -0500, Waiman Long wrote: > It was found when running fio sequential write test with a XFS ramdisk > on a 2-socket x86-64 system, the %CPU times as reported by perf were > as follows: > > 71.27% 0.28% fio [k] down_write > 70.99% 0.01% fio [k] call_rwsem_down_write_failed > 69.43% 1.18% fio [k] rwsem_down_write_failed > 65.51% 54.57% fio [k] osq_lock > 9.72% 7.99% fio [k] __raw_callee_save___kvm_vcpu_is_preempted > 4.16% 4.16% fio [k] __kvm_vcpu_is_preempted > > So making vcpu_is_preempted() a callee-save function has a pretty h...

...at 10:43:09AM -0500, Waiman Long wrote: > It was found when running fio sequential write test with a XFS ramdisk > on a VM running on a 2-socket x86-64 system, the %CPU times as reported > by perf were as follows: > > 69.75% 0.59% fio [k] down_write > 69.15% 0.01% fio [k] call_rwsem_down_write_failed > 67.12% 1.12% fio [k] rwsem_down_write_failed > 63.48% 52.77% fio [k] osq_lock > 9.46% 7.88% fio [k] __raw_callee_save___kvm_vcpu_is_preempt > 3.93% 3.93% fio [k] __kvm_vcpu_is_preempted > Thinking about this again, wouldn't something like the below also wor...

...;> It was found when running fio sequential write test with a XFS ramdisk >>> on a VM running on a 2-socket x86-64 system, the %CPU times as reported >>> by perf were as follows: >>> >>> 69.75% 0.59% fio [k] down_write >>> 69.15% 0.01% fio [k] call_rwsem_down_write_failed >>> 67.12% 1.12% fio [k] rwsem_down_write_failed >>> 63.48% 52.77% fio [k] osq_lock >>> 9.46% 7.88% fio [k] __raw_callee_save___kvm_vcpu_is_preempt >>> 3.93% 3.93% fio [k] __kvm_vcpu_is_preempted >>> >> Thinking about this again,...

...6ef4>] kernel_thread_helper+0x4/0x10 [<ffffffff8105f60b>] kthread+0x0/0x7e [<ffffffff81356ef0>] kernel_thread_helper+0x0/0x10 [<ffffffffffffffff>] 0xffffffffffffffff root at server:~# cat /proc/3393/stack [<ffffffff8100d02f>] load_TLS+0x7/0xa [<ffffffff811b42e3>] call_rwsem_down_write_failed+0x13/0x20 [<ffffffffa0546841>] ocfs2_commit_thread+0xf1/0x3a5 [ocfs2] [<ffffffff8105fcd3>] autoremove_wake_function+0x0/0x2a [<ffffffffa0546750>] ocfs2_commit_thread+0x0/0x3a5 [ocfs2] [<ffffffff8105f681>] kthread+0x76/0x7e [<ffffffff81356ef4>] kernel_thread_helper+0x...

...lt;ffffffff810c072e>] ? unlock_page+0x24/0x28 [ 413.409157] [<ffffffff810dbd38>] ? __do_fault+0x398/0x3cd [ 413.409157] [<ffffffff8161e3e4>] schedule+0x64/0x66 [ 413.409157] [<ffffffff8161ee9c>] rwsem_down_write_failed+0xf7/0x14a [ 413.409157] [<ffffffff8120d7f3>] call_rwsem_down_write_failed+0x13/0x20 [ 413.409157] [<ffffffff8161d555>] ? down_write+0x2e/0x32 [ 413.409157] [<ffffffff81105701>] thaw_super+0x1f/0xa7 [ 413.409157] [<ffffffff8111217b>] do_vfs_ioctl+0x202/0x486 [ 413.409157] [<ffffffff81129733>] ? SyS_fstatfs+0x33/0x3f [ 413.409157] [<f...

...fff814c5a34>] ? __mutex_lock_slowpath+0x284/0x3b0 [ 828.080275] [<ffffffff814c6f09>] schedule+0x29/0x70 [ 828.081867] [<ffffffff814c7d95>] rwsem_down_write_failed+0xf5/0x1c3 [ 828.083473] [<ffffffffa043a000>] ? 0xffffffffa0439fff [ 828.085083] [<ffffffff81279e33>] call_rwsem_down_write_failed+0x13/0x20 [ 828.086717] [<ffffffff814c5ec4>] ? down_write+0x24/0x26 [ 828.088366] [<ffffffff8118dffe>] grab_super+0x2e/0xa0 [ 828.090021] [<ffffffff8118e6f0>] sget+0x320/0x580 [ 828.091677] [<ffffffffa043e130>] ? btrfs_parse_early_options+0x190/0x190 [btrfs] [ 828...