| Message ID | 1469158863-28518-5-git-send-email-sjitindarsingh@gmail.com |
|---|---|
| State | Superseded |
| Headers | show |
On Thu, Jul 21, 2016 at 8:41 PM, Suraj Jitindar Singh <sjitindarsingh@gmail.com> wrote: > vcpu stats are used to collect information about a vcpu which can be viewed > in the debugfs. For example halt_attempted_poll and halt_successful_poll > are used to keep track of the number of times the vcpu attempts to and > successfully polls. These stats are currently not used on powerpc. > > Implement incrementation of the halt_attempted_poll and > halt_successful_poll vcpu stats for powerpc. Since these stats are summed > over all the vcpus for all running guests it doesn't matter which vcpu > they are attributed to, thus we choose the current runner vcpu of the > vcore. > > Also add new vcpu stats: halt_poll_success_ns, halt_poll_fail_ns and > halt_wait_ns to be used to accumulate the total time spend polling > successfully, polling unsuccessfully and waiting respectively, and > halt_successful_wait to accumulate the number of times the vcpu waits. > Given that halt_poll_success_ns, halt_poll_fail_ns and halt_wait_ns are > expressed in nanoseconds it is necessary to represent these as 64-bit > quantities, otherwise they would overflow after only about 4 seconds. > > Given that the total time spend either polling or waiting will be known and > the number of times that each was done, it will be possible to determine > the average poll and wait times. This will give the ability to tune the kvm > module parameters based on the calculated average wait and poll times. > > Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com> > Reviewed-by: David Matlack <dmatlack@google.com> > > --- > Change Log: > > V3 -> V4: > - Instead of accounting just wait and poll time, separate these > into successful_poll_time, failed_poll_time and wait_time. > V4 -> V5: > - Add single_task_running() check to polling loop I was expecting to see this in PATCH 3/5 with the halt-polling implementation. But otherwise, looks good, and the net effect is the same. > --- > arch/powerpc/include/asm/kvm_host.h | 4 ++++ > arch/powerpc/kvm/book3s.c | 4 ++++ > arch/powerpc/kvm/book3s_hv.c | 38 +++++++++++++++++++++++++++++++------ > 3 files changed, 40 insertions(+), 6 deletions(-) > > diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h > index f6304c5..f15ffc0 100644 > --- a/arch/powerpc/include/asm/kvm_host.h > +++ b/arch/powerpc/include/asm/kvm_host.h > @@ -114,8 +114,12 @@ struct kvm_vcpu_stat { > u64 emulated_inst_exits; > u64 dec_exits; > u64 ext_intr_exits; > + u64 halt_poll_success_ns; > + u64 halt_poll_fail_ns; > + u64 halt_wait_ns; > u64 halt_successful_poll; > u64 halt_attempted_poll; > + u64 halt_successful_wait; > u64 halt_poll_invalid; > u64 halt_wakeup; > u64 dbell_exits; > diff --git a/arch/powerpc/kvm/book3s.c b/arch/powerpc/kvm/book3s.c > index 47018fc..71eb8f3 100644 > --- a/arch/powerpc/kvm/book3s.c > +++ b/arch/powerpc/kvm/book3s.c > @@ -52,8 +52,12 @@ struct kvm_stats_debugfs_item debugfs_entries[] = { > { "dec", VCPU_STAT(dec_exits) }, > { "ext_intr", VCPU_STAT(ext_intr_exits) }, > { "queue_intr", VCPU_STAT(queue_intr) }, > + { "halt_poll_success_ns", VCPU_STAT(halt_poll_success_ns) }, > + { "halt_poll_fail_ns", VCPU_STAT(halt_poll_fail_ns) }, > + { "halt_wait_ns", VCPU_STAT(halt_wait_ns) }, > { "halt_successful_poll", VCPU_STAT(halt_successful_poll), }, > { "halt_attempted_poll", VCPU_STAT(halt_attempted_poll), }, > + { "halt_successful_wait", VCPU_STAT(halt_successful_wait) }, > { "halt_poll_invalid", VCPU_STAT(halt_poll_invalid) }, > { "halt_wakeup", VCPU_STAT(halt_wakeup) }, > { "pf_storage", VCPU_STAT(pf_storage) }, > diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c > index a9de1d4..b1d9e88 100644 > --- a/arch/powerpc/kvm/book3s_hv.c > +++ b/arch/powerpc/kvm/book3s_hv.c > @@ -2679,15 +2679,16 @@ static int kvmppc_vcore_check_block(struct kvmppc_vcore *vc) > */ > static void kvmppc_vcore_blocked(struct kvmppc_vcore *vc) > { > + ktime_t cur, start_poll, start_wait; > int do_sleep = 1; > - ktime_t cur, start; > u64 block_ns; > DECLARE_SWAITQUEUE(wait); > > /* Poll for pending exceptions and ceded state */ > - cur = start = ktime_get(); > + cur = start_poll = ktime_get(); > if (vc->halt_poll_ns) { > - ktime_t stop = ktime_add_ns(start, vc->halt_poll_ns); > + ktime_t stop = ktime_add_ns(start_poll, vc->halt_poll_ns); > + ++vc->runner->stat.halt_attempted_poll; > > vc->vcore_state = VCORE_POLLING; > spin_unlock(&vc->lock); > @@ -2698,13 +2699,15 @@ static void kvmppc_vcore_blocked(struct kvmppc_vcore *vc) > break; > } > cur = ktime_get(); > - } while (ktime_before(cur, stop)); > + } while (single_task_running() && ktime_before(cur, stop)); > > spin_lock(&vc->lock); > vc->vcore_state = VCORE_INACTIVE; > > - if (!do_sleep) > + if (!do_sleep) { > + ++vc->runner->stat.halt_successful_poll; > goto out; > + } > } > > prepare_to_swait(&vc->wq, &wait, TASK_INTERRUPTIBLE); > @@ -2712,9 +2715,14 @@ static void kvmppc_vcore_blocked(struct kvmppc_vcore *vc) > if (kvmppc_vcore_check_block(vc)) { > finish_swait(&vc->wq, &wait); > do_sleep = 0; > + /* If we polled, count this as a successful poll */ > + if (vc->halt_poll_ns) > + ++vc->runner->stat.halt_successful_poll; > goto out; > } > > + start_wait = ktime_get(); > + > vc->vcore_state = VCORE_SLEEPING; > trace_kvmppc_vcore_blocked(vc, 0); > spin_unlock(&vc->lock); > @@ -2723,11 +2731,29 @@ static void kvmppc_vcore_blocked(struct kvmppc_vcore *vc) > spin_lock(&vc->lock); > vc->vcore_state = VCORE_INACTIVE; > trace_kvmppc_vcore_blocked(vc, 1); > + ++vc->runner->stat.halt_successful_wait; > > cur = ktime_get(); > > out: > - block_ns = ktime_to_ns(cur) - ktime_to_ns(start); > + block_ns = ktime_to_ns(cur) - ktime_to_ns(start_poll); > + > + /* Attribute wait time */ > + if (do_sleep) { > + vc->runner->stat.halt_wait_ns += > + ktime_to_ns(cur) - ktime_to_ns(start_wait); > + /* Attribute failed poll time */ > + if (vc->halt_poll_ns) > + vc->runner->stat.halt_poll_fail_ns += > + ktime_to_ns(start_wait) - > + ktime_to_ns(start_poll); > + } else { > + /* Attribute successful poll time */ > + if (vc->halt_poll_ns) > + vc->runner->stat.halt_poll_success_ns += > + ktime_to_ns(cur) - > + ktime_to_ns(start_poll); > + } > > /* Adjust poll time */ > if (halt_poll_max_ns) { > -- > 2.5.5 > -- To unsubscribe from this list: send the line "unsubscribe kvm-ppc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 23/07/16 07:53, David Matlack wrote: > On Thu, Jul 21, 2016 at 8:41 PM, Suraj Jitindar Singh > <sjitindarsingh@gmail.com> wrote: >> vcpu stats are used to collect information about a vcpu which can be viewed >> in the debugfs. For example halt_attempted_poll and halt_successful_poll >> are used to keep track of the number of times the vcpu attempts to and >> successfully polls. These stats are currently not used on powerpc. >> >> Implement incrementation of the halt_attempted_poll and >> halt_successful_poll vcpu stats for powerpc. Since these stats are summed >> over all the vcpus for all running guests it doesn't matter which vcpu >> they are attributed to, thus we choose the current runner vcpu of the >> vcore. >> >> Also add new vcpu stats: halt_poll_success_ns, halt_poll_fail_ns and >> halt_wait_ns to be used to accumulate the total time spend polling >> successfully, polling unsuccessfully and waiting respectively, and >> halt_successful_wait to accumulate the number of times the vcpu waits. >> Given that halt_poll_success_ns, halt_poll_fail_ns and halt_wait_ns are >> expressed in nanoseconds it is necessary to represent these as 64-bit >> quantities, otherwise they would overflow after only about 4 seconds. >> >> Given that the total time spend either polling or waiting will be known and >> the number of times that each was done, it will be possible to determine >> the average poll and wait times. This will give the ability to tune the kvm >> module parameters based on the calculated average wait and poll times. >> >> Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com> >> Reviewed-by: David Matlack <dmatlack@google.com> >> >> --- >> Change Log: >> >> V3 -> V4: >> - Instead of accounting just wait and poll time, separate these >> into successful_poll_time, failed_poll_time and wait_time. >> V4 -> V5: >> - Add single_task_running() check to polling loop > I was expecting to see this in PATCH 3/5 with the halt-polling > implementation. But otherwise, looks good, and the net effect is the > same That would have made more sense, obviously that was my Friday afternoon brain. > . > >> --- >> arch/powerpc/include/asm/kvm_host.h | 4 ++++ >> arch/powerpc/kvm/book3s.c | 4 ++++ >> arch/powerpc/kvm/book3s_hv.c | 38 +++++++++++++++++++++++++++++++------ >> 3 files changed, 40 insertions(+), 6 deletions(-) >> >> diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h >> index f6304c5..f15ffc0 100644 >> --- a/arch/powerpc/include/asm/kvm_host.h >> +++ b/arch/powerpc/include/asm/kvm_host.h >> @@ -114,8 +114,12 @@ struct kvm_vcpu_stat { >> u64 emulated_inst_exits; >> u64 dec_exits; >> u64 ext_intr_exits; >> + u64 halt_poll_success_ns; >> + u64 halt_poll_fail_ns; >> + u64 halt_wait_ns; >> u64 halt_successful_poll; >> u64 halt_attempted_poll; >> + u64 halt_successful_wait; >> u64 halt_poll_invalid; >> u64 halt_wakeup; >> u64 dbell_exits; >> diff --git a/arch/powerpc/kvm/book3s.c b/arch/powerpc/kvm/book3s.c >> index 47018fc..71eb8f3 100644 >> --- a/arch/powerpc/kvm/book3s.c >> +++ b/arch/powerpc/kvm/book3s.c >> @@ -52,8 +52,12 @@ struct kvm_stats_debugfs_item debugfs_entries[] = { >> { "dec", VCPU_STAT(dec_exits) }, >> { "ext_intr", VCPU_STAT(ext_intr_exits) }, >> { "queue_intr", VCPU_STAT(queue_intr) }, >> + { "halt_poll_success_ns", VCPU_STAT(halt_poll_success_ns) }, >> + { "halt_poll_fail_ns", VCPU_STAT(halt_poll_fail_ns) }, >> + { "halt_wait_ns", VCPU_STAT(halt_wait_ns) }, >> { "halt_successful_poll", VCPU_STAT(halt_successful_poll), }, >> { "halt_attempted_poll", VCPU_STAT(halt_attempted_poll), }, >> + { "halt_successful_wait", VCPU_STAT(halt_successful_wait) }, >> { "halt_poll_invalid", VCPU_STAT(halt_poll_invalid) }, >> { "halt_wakeup", VCPU_STAT(halt_wakeup) }, >> { "pf_storage", VCPU_STAT(pf_storage) }, >> diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c >> index a9de1d4..b1d9e88 100644 >> --- a/arch/powerpc/kvm/book3s_hv.c >> +++ b/arch/powerpc/kvm/book3s_hv.c >> @@ -2679,15 +2679,16 @@ static int kvmppc_vcore_check_block(struct kvmppc_vcore *vc) >> */ >> static void kvmppc_vcore_blocked(struct kvmppc_vcore *vc) >> { >> + ktime_t cur, start_poll, start_wait; >> int do_sleep = 1; >> - ktime_t cur, start; >> u64 block_ns; >> DECLARE_SWAITQUEUE(wait); >> >> /* Poll for pending exceptions and ceded state */ >> - cur = start = ktime_get(); >> + cur = start_poll = ktime_get(); >> if (vc->halt_poll_ns) { >> - ktime_t stop = ktime_add_ns(start, vc->halt_poll_ns); >> + ktime_t stop = ktime_add_ns(start_poll, vc->halt_poll_ns); >> + ++vc->runner->stat.halt_attempted_poll; >> >> vc->vcore_state = VCORE_POLLING; >> spin_unlock(&vc->lock); >> @@ -2698,13 +2699,15 @@ static void kvmppc_vcore_blocked(struct kvmppc_vcore *vc) >> break; >> } >> cur = ktime_get(); >> - } while (ktime_before(cur, stop)); >> + } while (single_task_running() && ktime_before(cur, stop)); >> >> spin_lock(&vc->lock); >> vc->vcore_state = VCORE_INACTIVE; >> >> - if (!do_sleep) >> + if (!do_sleep) { >> + ++vc->runner->stat.halt_successful_poll; >> goto out; >> + } >> } >> >> prepare_to_swait(&vc->wq, &wait, TASK_INTERRUPTIBLE); >> @@ -2712,9 +2715,14 @@ static void kvmppc_vcore_blocked(struct kvmppc_vcore *vc) >> if (kvmppc_vcore_check_block(vc)) { >> finish_swait(&vc->wq, &wait); >> do_sleep = 0; >> + /* If we polled, count this as a successful poll */ >> + if (vc->halt_poll_ns) >> + ++vc->runner->stat.halt_successful_poll; >> goto out; >> } >> >> + start_wait = ktime_get(); >> + >> vc->vcore_state = VCORE_SLEEPING; >> trace_kvmppc_vcore_blocked(vc, 0); >> spin_unlock(&vc->lock); >> @@ -2723,11 +2731,29 @@ static void kvmppc_vcore_blocked(struct kvmppc_vcore *vc) >> spin_lock(&vc->lock); >> vc->vcore_state = VCORE_INACTIVE; >> trace_kvmppc_vcore_blocked(vc, 1); >> + ++vc->runner->stat.halt_successful_wait; >> >> cur = ktime_get(); >> >> out: >> - block_ns = ktime_to_ns(cur) - ktime_to_ns(start); >> + block_ns = ktime_to_ns(cur) - ktime_to_ns(start_poll); >> + >> + /* Attribute wait time */ >> + if (do_sleep) { >> + vc->runner->stat.halt_wait_ns += >> + ktime_to_ns(cur) - ktime_to_ns(start_wait); >> + /* Attribute failed poll time */ >> + if (vc->halt_poll_ns) >> + vc->runner->stat.halt_poll_fail_ns += >> + ktime_to_ns(start_wait) - >> + ktime_to_ns(start_poll); >> + } else { >> + /* Attribute successful poll time */ >> + if (vc->halt_poll_ns) >> + vc->runner->stat.halt_poll_success_ns += >> + ktime_to_ns(cur) - >> + ktime_to_ns(start_poll); >> + } >> >> /* Adjust poll time */ >> if (halt_poll_max_ns) { >> -- >> 2.5.5 >> -- To unsubscribe from this list: send the line "unsubscribe kvm-ppc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h index f6304c5..f15ffc0 100644 --- a/arch/powerpc/include/asm/kvm_host.h +++ b/arch/powerpc/include/asm/kvm_host.h @@ -114,8 +114,12 @@ struct kvm_vcpu_stat { u64 emulated_inst_exits; u64 dec_exits; u64 ext_intr_exits; + u64 halt_poll_success_ns; + u64 halt_poll_fail_ns; + u64 halt_wait_ns; u64 halt_successful_poll; u64 halt_attempted_poll; + u64 halt_successful_wait; u64 halt_poll_invalid; u64 halt_wakeup; u64 dbell_exits; diff --git a/arch/powerpc/kvm/book3s.c b/arch/powerpc/kvm/book3s.c index 47018fc..71eb8f3 100644 --- a/arch/powerpc/kvm/book3s.c +++ b/arch/powerpc/kvm/book3s.c @@ -52,8 +52,12 @@ struct kvm_stats_debugfs_item debugfs_entries[] = { { "dec", VCPU_STAT(dec_exits) }, { "ext_intr", VCPU_STAT(ext_intr_exits) }, { "queue_intr", VCPU_STAT(queue_intr) }, + { "halt_poll_success_ns", VCPU_STAT(halt_poll_success_ns) }, + { "halt_poll_fail_ns", VCPU_STAT(halt_poll_fail_ns) }, + { "halt_wait_ns", VCPU_STAT(halt_wait_ns) }, { "halt_successful_poll", VCPU_STAT(halt_successful_poll), }, { "halt_attempted_poll", VCPU_STAT(halt_attempted_poll), }, + { "halt_successful_wait", VCPU_STAT(halt_successful_wait) }, { "halt_poll_invalid", VCPU_STAT(halt_poll_invalid) }, { "halt_wakeup", VCPU_STAT(halt_wakeup) }, { "pf_storage", VCPU_STAT(pf_storage) }, diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index a9de1d4..b1d9e88 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -2679,15 +2679,16 @@ static int kvmppc_vcore_check_block(struct kvmppc_vcore *vc) */ static void kvmppc_vcore_blocked(struct kvmppc_vcore *vc) { + ktime_t cur, start_poll, start_wait; int do_sleep = 1; - ktime_t cur, start; u64 block_ns; DECLARE_SWAITQUEUE(wait); /* Poll for pending exceptions and ceded state */ - cur = start = ktime_get(); + cur = start_poll = ktime_get(); if (vc->halt_poll_ns) { - ktime_t stop = ktime_add_ns(start, vc->halt_poll_ns); + ktime_t stop = ktime_add_ns(start_poll, vc->halt_poll_ns); + ++vc->runner->stat.halt_attempted_poll; vc->vcore_state = VCORE_POLLING; spin_unlock(&vc->lock); @@ -2698,13 +2699,15 @@ static void kvmppc_vcore_blocked(struct kvmppc_vcore *vc) break; } cur = ktime_get(); - } while (ktime_before(cur, stop)); + } while (single_task_running() && ktime_before(cur, stop)); spin_lock(&vc->lock); vc->vcore_state = VCORE_INACTIVE; - if (!do_sleep) + if (!do_sleep) { + ++vc->runner->stat.halt_successful_poll; goto out; + } } prepare_to_swait(&vc->wq, &wait, TASK_INTERRUPTIBLE); @@ -2712,9 +2715,14 @@ static void kvmppc_vcore_blocked(struct kvmppc_vcore *vc) if (kvmppc_vcore_check_block(vc)) { finish_swait(&vc->wq, &wait); do_sleep = 0; + /* If we polled, count this as a successful poll */ + if (vc->halt_poll_ns) + ++vc->runner->stat.halt_successful_poll; goto out; } + start_wait = ktime_get(); + vc->vcore_state = VCORE_SLEEPING; trace_kvmppc_vcore_blocked(vc, 0); spin_unlock(&vc->lock); @@ -2723,11 +2731,29 @@ static void kvmppc_vcore_blocked(struct kvmppc_vcore *vc) spin_lock(&vc->lock); vc->vcore_state = VCORE_INACTIVE; trace_kvmppc_vcore_blocked(vc, 1); + ++vc->runner->stat.halt_successful_wait; cur = ktime_get(); out: - block_ns = ktime_to_ns(cur) - ktime_to_ns(start); + block_ns = ktime_to_ns(cur) - ktime_to_ns(start_poll); + + /* Attribute wait time */ + if (do_sleep) { + vc->runner->stat.halt_wait_ns += + ktime_to_ns(cur) - ktime_to_ns(start_wait); + /* Attribute failed poll time */ + if (vc->halt_poll_ns) + vc->runner->stat.halt_poll_fail_ns += + ktime_to_ns(start_wait) - + ktime_to_ns(start_poll); + } else { + /* Attribute successful poll time */ + if (vc->halt_poll_ns) + vc->runner->stat.halt_poll_success_ns += + ktime_to_ns(cur) - + ktime_to_ns(start_poll); + } /* Adjust poll time */ if (halt_poll_max_ns) {