diff options
Diffstat (limited to 'llvm/include/pmu/pmu.h')
| -rw-r--r-- | llvm/include/pmu/pmu.h | 170 |
1 files changed, 170 insertions, 0 deletions
diff --git a/llvm/include/pmu/pmu.h b/llvm/include/pmu/pmu.h new file mode 100644 index 0000000..89a7c98 --- /dev/null +++ b/llvm/include/pmu/pmu.h @@ -0,0 +1,170 @@ +/* + * (C) 2018 by Computer System Laboratory, IIS, Academia Sinica, Taiwan. + * See COPYRIGHT in top-level directory. + * + * Hardware Performance Monitoring Unit (PMU), C++ interfaces. + */ + +#ifndef __PMU_H +#define __PMU_H + +#include <vector> +#include <memory> +#include <stdint.h> + +namespace pmu { + +#define PMU_GROUP_EVENTS (8) +#define PMU_TIMER_PERIOD (400) /* micro-second */ +#define PMU_INVALID_HNDL ((Handle)-1) + +typedef unsigned Handle; +/* Sampling event overflow handling. */ +typedef std::vector<uint64_t> SampleList; +typedef std::unique_ptr<SampleList> SampleDataPtr; +typedef void (*SampleHandlerTy)(Handle Hndl, SampleDataPtr Data, void *Opaque); + +/* Error code. */ +enum { + PMU_OK = 0, /* No error */ + PMU_EINVAL = -1, /* Invalid argument */ + PMU_ENOMEM = -2, /* Insufficient memory */ + PMU_ENOEVENT = -3, /* Pre-defined event not available */ + PMU_EEVENT = -4, /* Hardware event error */ + PMU_EPERM = -5, /* Permission denied */ + PMU_EINTER = -6, /* Internal error */ + PMU_EDECODER = -7, /* Instruction trace decoder error */ +}; + +/* Pre-defined event code. */ +enum { + /* Basic events */ + PMU_CPU_CYCLES = 0, + PMU_REF_CPU_CYCLES, + PMU_INSTRUCTIONS, + PMU_LLC_REFERENCES, + PMU_LLC_MISSES, + PMU_BRANCH_INSTRUCTIONS, + PMU_BRANCH_MISSES, + /* Instruction cache events */ + PMU_ICACHE_HITS, + PMU_ICACHE_MISSES, + /* Memory instruction events */ + PMU_MEM_LOADS, + PMU_MEM_STORES, + + PMU_EVENT_MAX, +}; + +/* PMU initial configuration. */ +struct PMUConfig { + /* Input */ + int SignalReceiver; /* TID of the signal receiver. 0 for auto-select. */ + uint32_t Timeout; /* Timer period in micro-second. 0 for auto-select. */ + + /* Output */ + int PerfVersion; /* Perf version used in this PMU tool */ + int OSPerfVersion; /* Perf version used in the OS kernel */ +}; + +/* Config for sampling with one or multiple event(s).*/ +struct SampleConfig { + unsigned NumEvents; /* Number of events in the event group */ + unsigned EventCode[PMU_GROUP_EVENTS]; /* Event group. The 1st event is the leader. */ + unsigned NumPages; /* Number of pages as the sample buffer size. (must be 2^n) */ + uint64_t Period; /* Sampling period of the group leader. */ + uint64_t Watermark; /* Bytes before wakeup. 0 for every timer period. */ + SampleHandlerTy SampleHandler; /* User handler routine */ + void *Opaque; /* An opaque pointer passed to the overflow handler. */ +}; + +/* Config for sampling with only one event. */ +struct Sample1Config { + unsigned EventCode; /* Pre-defined event to trigger counter overflow */ + unsigned NumPages; /* Number of pages as the sample buffer size. (must be 2^n) */ + uint64_t Period; /* Sampling period */ + uint64_t Watermark; /* Bytes before wakeup. 0 for every timer period. */ + SampleHandlerTy SampleHandler; /* User handler routine */ + void *Opaque; /* An opaque pointer passed to the overflow handler. */ +}; + +/* + * PMU main tools. + */ +class PMU { + PMU() = delete; + ~PMU() = delete; + +public: + /* Initialize the PMU module. */ + static int Init(PMUConfig &Config); + + /* Finalize the PMU module. */ + static int Finalize(void); + + /* Stop the PMU module. When the PMU module is paused, the user can continue + * to use counting events, but the overflow handler will not be invoked. */ + static int Pause(void); + + /* Restart the PMU module. After the PMU module is resumed, the overflow + * handler will be invoked. */ + static int Resume(void); + + /* Start a counting/sampling/tracing event. */ + static int Start(Handle Hndl); + + /* Stop a counting/sampling/tracing event. */ + static int Stop(Handle Hndl); + + /* Reset the hardware counter. */ + static int Reset(Handle Hndl); + + /* Remove an event. */ + static int Cleanup(Handle Hndl); + + /* Start/stop a sampling/tracing event without acquiring a lock. + * Note that these two function should only be used within the overflow + * handler. Since the overflow handling is already in a locked section, + * acquiring a lock is not required. */ + static int StartUnlocked(Handle Hndl); + static int StopUnlocked(Handle Hndl); + + /* Open an event using the pre-defined event code. */ + static int CreateEvent(unsigned EventCode, Handle &Hndl); + + /* Open an event using the raw event number and umask value. + * The raw event code is computed as (RawEvent | (Umask << 8)). */ + static int CreateRawEvent(unsigned RawEvent, unsigned Umask, Handle &Hndl); + + /* Open a sampling event, with the 1st EventCode as the interrupt event. + * The sample data will be recorded in a vector of type 'uint64_t'. + * The following vector shows the data format of sampling with N events: + * { pc, val1, val2, ..., valN, # 1st sample + * ... + * pc, val1, val2, ..., valN }; # nth sample + * + * Note that ownwership of the output vector is transferred to the user. + * It is the user's responsibility to free the resource of the vector. */ + static int CreateSampleEvent(SampleConfig &Config, Handle &Hndl); + + /* Generate an IP histogram, using EventCode as the interrupt event. + * The IP histogram will be recorded in a vector of type 'uint64_t' with + * the format: { pc1, pc2, pc3, ..., pcN }. + * Note that ownwership of the output vector is transferred to the user. + * It is the user's responsibility to free the resource of the vector. */ + static int CreateSampleIP(Sample1Config &Config, Handle &Hndl); + + /* Read value from the hardware counter. */ + static int ReadEvent(Handle Hndl, uint64_t &Value); + + /* Convert error code to string. */ + static const char *strerror(int ErrCode); +}; + +} /* namespace pmu */ + +#endif /* __PMU_H */ + +/* + * vim: ts=8 sts=4 sw=4 expandtab + */ |
