diff options
author | Peter Zijlstra <a.p.zijlstra@chello.nl> | 2010-06-16 14:37:10 +0200 |
---|---|---|
committer | Ingo Molnar <mingo@elte.hu> | 2010-09-09 20:46:30 +0200 |
commit | a4eaf7f14675cb512d69f0c928055e73d0c6d252 (patch) | |
tree | e8a0f631fc28d4bd9becd2e9e2c71743c64ee3ec /arch/alpha | |
parent | fa407f35e0298d841e4088f95a7f9cf6e725c6d5 (diff) | |
download | kernel_samsung_smdk4412-a4eaf7f14675cb512d69f0c928055e73d0c6d252.zip kernel_samsung_smdk4412-a4eaf7f14675cb512d69f0c928055e73d0c6d252.tar.gz kernel_samsung_smdk4412-a4eaf7f14675cb512d69f0c928055e73d0c6d252.tar.bz2 |
perf: Rework the PMU methods
Replace pmu::{enable,disable,start,stop,unthrottle} with
pmu::{add,del,start,stop}, all of which take a flags argument.
The new interface extends the capability to stop a counter while
keeping it scheduled on the PMU. We replace the throttled state with
the generic stopped state.
This also allows us to efficiently stop/start counters over certain
code paths (like IRQ handlers).
It also allows scheduling a counter without it starting, allowing for
a generic frozen state (useful for rotating stopped counters).
The stopped state is implemented in two different ways, depending on
how the architecture implemented the throttled state:
1) We disable the counter:
a) the pmu has per-counter enable bits, we flip that
b) we program a NOP event, preserving the counter state
2) We store the counter state and ignore all read/overflow events
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: paulus <paulus@samba.org>
Cc: stephane eranian <eranian@googlemail.com>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Lin Ming <ming.m.lin@intel.com>
Cc: Yanmin <yanmin_zhang@linux.intel.com>
Cc: Deng-Cheng Zhu <dengcheng.zhu@gmail.com>
Cc: David Miller <davem@davemloft.net>
Cc: Michael Cree <mcree@orcon.net.nz>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch/alpha')
-rw-r--r-- | arch/alpha/kernel/perf_event.c | 71 |
1 files changed, 53 insertions, 18 deletions
diff --git a/arch/alpha/kernel/perf_event.c b/arch/alpha/kernel/perf_event.c index 3e26073..380ef02 100644 --- a/arch/alpha/kernel/perf_event.c +++ b/arch/alpha/kernel/perf_event.c @@ -307,7 +307,7 @@ again: new_raw_count) != prev_raw_count) goto again; - delta = (new_raw_count - (prev_raw_count & alpha_pmu->pmc_count_mask[idx])) + ovf; + delta = (new_raw_count - (prev_raw_count & alpha_pmu->pmc_count_mask[idx])) + ovf; /* It is possible on very rare occasions that the PMC has overflowed * but the interrupt is yet to come. Detect and fix this situation. @@ -402,14 +402,13 @@ static void maybe_change_configuration(struct cpu_hw_events *cpuc) struct hw_perf_event *hwc = &pe->hw; int idx = hwc->idx; - if (cpuc->current_idx[j] != PMC_NO_INDEX) { - cpuc->idx_mask |= (1<<cpuc->current_idx[j]); - continue; + if (cpuc->current_idx[j] == PMC_NO_INDEX) { + alpha_perf_event_set_period(pe, hwc, idx); + cpuc->current_idx[j] = idx; } - alpha_perf_event_set_period(pe, hwc, idx); - cpuc->current_idx[j] = idx; - cpuc->idx_mask |= (1<<cpuc->current_idx[j]); + if (!(hwc->state & PERF_HES_STOPPED)) + cpuc->idx_mask |= (1<<cpuc->current_idx[j]); } cpuc->config = cpuc->event[0]->hw.config_base; } @@ -420,7 +419,7 @@ static void maybe_change_configuration(struct cpu_hw_events *cpuc) * - this function is called from outside this module via the pmu struct * returned from perf event initialisation. */ -static int alpha_pmu_enable(struct perf_event *event) +static int alpha_pmu_add(struct perf_event *event, int flags) { struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events); int n0; @@ -455,6 +454,10 @@ static int alpha_pmu_enable(struct perf_event *event) } } + hwc->state = PERF_HES_UPTODATE; + if (!(flags & PERF_EF_START)) + hwc->state |= PERF_HES_STOPPED; + local_irq_restore(flags); perf_pmu_enable(event->pmu); @@ -467,7 +470,7 @@ static int alpha_pmu_enable(struct perf_event *event) * - this function is called from outside this module via the pmu struct * returned from perf event initialisation. */ -static void alpha_pmu_disable(struct perf_event *event) +static void alpha_pmu_del(struct perf_event *event, int flags) { struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events); struct hw_perf_event *hwc = &event->hw; @@ -514,13 +517,44 @@ static void alpha_pmu_read(struct perf_event *event) } -static void alpha_pmu_unthrottle(struct perf_event *event) +static void alpha_pmu_stop(struct perf_event *event, int flags) { struct hw_perf_event *hwc = &event->hw; struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events); + if (!(hwc->state & PERF_HES_STOPPED)) { + cpuc->idx_mask &= !(1UL<<hwc->idx); + hwc->state |= PERF_HES_STOPPED; + } + + if ((flags & PERF_EF_UPDATE) && !(hwc->state & PERF_HES_UPTODATE)) { + alpha_perf_event_update(event, hwc, hwc->idx, 0); + hwc->state |= PERF_HES_UPTODATE; + } + + if (cpuc->enabled) + wrperfmon(PERFMON_CMD_ENABLE, (1UL<<hwc->idx)); +} + + +static void alpha_pmu_start(struct perf_event *event, int flags) +{ + struct hw_perf_event *hwc = &event->hw; + struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events); + + if (WARN_ON_ONCE(!(hwc->state & PERF_HES_STOPPED))) + return; + + if (flags & PERF_EF_RELOAD) { + WARN_ON_ONCE(!(hwc->state & PERF_HES_UPTODATE)); + alpha_perf_event_set_period(event, hwc, hwc->idx); + } + + hwc->state = 0; + cpuc->idx_mask |= 1UL<<hwc->idx; - wrperfmon(PERFMON_CMD_ENABLE, (1UL<<hwc->idx)); + if (cpuc->enabled) + wrperfmon(PERFMON_CMD_ENABLE, (1UL<<hwc->idx)); } @@ -671,7 +705,7 @@ static int alpha_pmu_event_init(struct perf_event *event) /* * Main entry point - enable HW performance counters. */ -static void alpha_pmu_pmu_enable(struct pmu *pmu) +static void alpha_pmu_enable(struct pmu *pmu) { struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events); @@ -697,7 +731,7 @@ static void alpha_pmu_pmu_enable(struct pmu *pmu) * Main entry point - disable HW performance counters. */ -static void alpha_pmu_pmu_disable(struct pmu *pmu) +static void alpha_pmu_disable(struct pmu *pmu) { struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events); @@ -711,13 +745,14 @@ static void alpha_pmu_pmu_disable(struct pmu *pmu) } static struct pmu pmu = { - .pmu_enable = alpha_pmu_pmu_enable, - .pmu_disable = alpha_pmu_pmu_disable, + .pmu_enable = alpha_pmu_enable, + .pmu_disable = alpha_pmu_disable, .event_init = alpha_pmu_event_init, - .enable = alpha_pmu_enable, - .disable = alpha_pmu_disable, + .add = alpha_pmu_add, + .del = alpha_pmu_del, + .start = alpha_pmu_start, + .stop = alpha_pmu_stop, .read = alpha_pmu_read, - .unthrottle = alpha_pmu_unthrottle, }; |