From f708223d49ac39f5af1643985056206c98033f5b Mon Sep 17 00:00:00 2001 From: Paul Mackerras Date: Wed, 8 Apr 2009 20:30:18 +1000 Subject: perf_counter: powerpc: set sample enable bit for marked instruction events Impact: enable access to hardware feature POWER processors have the ability to "mark" a subset of the instructions and provide more detailed information on what happens to the marked instructions as they flow through the pipeline. This marking is enabled by the "sample enable" bit in MMCRA, and there are synchronization requirements around setting and clearing the bit. This adds logic to the processor-specific back-ends so that they know which events relate to marked instructions and set the sampling enable bit if any event that we want to put on the PMU is a marked instruction event. It also adds logic to the generic powerpc code to do the necessary synchronization if that bit is set. Signed-off-by: Paul Mackerras Cc: Peter Zijlstra LKML-Reference: <18908.31930.1024.228867@cargo.ozlabs.ibm.com> Signed-off-by: Ingo Molnar --- arch/powerpc/kernel/power5-pmu.c | 96 +++++++++++++++++++++++++++++++++++++++- 1 file changed, 95 insertions(+), 1 deletion(-) (limited to 'arch/powerpc/kernel/power5-pmu.c') diff --git a/arch/powerpc/kernel/power5-pmu.c b/arch/powerpc/kernel/power5-pmu.c index 379ed1087cca..116c4bb1809e 100644 --- a/arch/powerpc/kernel/power5-pmu.c +++ b/arch/powerpc/kernel/power5-pmu.c @@ -290,10 +290,102 @@ static int power5_get_alternatives(unsigned int event, unsigned int alt[]) return nalt; } +/* + * Map of which direct events on which PMCs are marked instruction events. + * Indexed by PMCSEL value, bit i (LE) set if PMC i is a marked event. + * Bit 0 is set if it is marked for all PMCs. + * The 0x80 bit indicates a byte decode PMCSEL value. + */ +static unsigned char direct_event_is_marked[0x28] = { + 0, /* 00 */ + 0x1f, /* 01 PM_IOPS_CMPL */ + 0x2, /* 02 PM_MRK_GRP_DISP */ + 0xe, /* 03 PM_MRK_ST_CMPL, PM_MRK_ST_GPS, PM_MRK_ST_CMPL_INT */ + 0, /* 04 */ + 0x1c, /* 05 PM_MRK_BRU_FIN, PM_MRK_INST_FIN, PM_MRK_CRU_FIN */ + 0x80, /* 06 */ + 0x80, /* 07 */ + 0, 0, 0,/* 08 - 0a */ + 0x18, /* 0b PM_THRESH_TIMEO, PM_MRK_GRP_TIMEO */ + 0, /* 0c */ + 0x80, /* 0d */ + 0x80, /* 0e */ + 0, /* 0f */ + 0, /* 10 */ + 0x14, /* 11 PM_MRK_GRP_BR_REDIR, PM_MRK_GRP_IC_MISS */ + 0, /* 12 */ + 0x10, /* 13 PM_MRK_GRP_CMPL */ + 0x1f, /* 14 PM_GRP_MRK, PM_MRK_{FXU,FPU,LSU}_FIN */ + 0x2, /* 15 PM_MRK_GRP_ISSUED */ + 0x80, /* 16 */ + 0x80, /* 17 */ + 0, 0, 0, 0, 0, + 0x80, /* 1d */ + 0x80, /* 1e */ + 0, /* 1f */ + 0x80, /* 20 */ + 0x80, /* 21 */ + 0x80, /* 22 */ + 0x80, /* 23 */ + 0x80, /* 24 */ + 0x80, /* 25 */ + 0x80, /* 26 */ + 0x80, /* 27 */ +}; + +/* + * Returns 1 if event counts things relating to marked instructions + * and thus needs the MMCRA_SAMPLE_ENABLE bit set, or 0 if not. + */ +static int power5_marked_instr_event(unsigned int event) +{ + int pmc, psel; + int bit, byte, unit; + u32 mask; + + pmc = (event >> PM_PMC_SH) & PM_PMC_MSK; + psel = event & PM_PMCSEL_MSK; + if (pmc >= 5) + return 0; + + bit = -1; + if (psel < sizeof(direct_event_is_marked)) { + if (direct_event_is_marked[psel] & (1 << pmc)) + return 1; + if (direct_event_is_marked[psel] & 0x80) + bit = 4; + else if (psel == 0x08) + bit = pmc - 1; + else if (psel == 0x10) + bit = 4 - pmc; + else if (psel == 0x1b && (pmc == 1 || pmc == 3)) + bit = 4; + } else if ((psel & 0x58) == 0x40) + bit = psel & 7; + + if (!(event & PM_BUSEVENT_MSK)) + return 0; + + byte = (event >> PM_BYTE_SH) & PM_BYTE_MSK; + unit = (event >> PM_UNIT_SH) & PM_UNIT_MSK; + if (unit == PM_LSU0) { + /* byte 1 bits 0-7, byte 2 bits 0,2-4,6 */ + mask = 0x5dff00; + } else if (unit == PM_LSU1 && byte >= 4) { + byte -= 4; + /* byte 4 bits 1,3,5,7, byte 5 bits 6-7, byte 7 bits 0-4,6 */ + mask = 0x5f00c0aa; + } else + return 0; + + return (mask >> (byte * 8 + bit)) & 1; +} + static int power5_compute_mmcr(unsigned int event[], int n_ev, unsigned int hwc[], u64 mmcr[]) { u64 mmcr1 = 0; + u64 mmcra = 0; unsigned int pmc, unit, byte, psel; unsigned int ttm, grp; int i, isbus, bit, grsel; @@ -430,6 +522,8 @@ static int power5_compute_mmcr(unsigned int event[], int n_ev, grsel = (event[i] >> PM_GRS_SH) & PM_GRS_MSK; mmcr1 |= (u64)grsel << grsel_shift[bit]; } + if (power5_marked_instr_event(event[i])) + mmcra |= MMCRA_SAMPLE_ENABLE; if (pmc <= 3) mmcr1 |= psel << MMCR1_PMCSEL_SH(pmc); hwc[i] = pmc; @@ -442,7 +536,7 @@ static int power5_compute_mmcr(unsigned int event[], int n_ev, if (pmc_inuse & 0x3e) mmcr[0] |= MMCR0_PMCjCE; mmcr[1] = mmcr1; - mmcr[2] = 0; + mmcr[2] = mmcra; return 0; } -- cgit v1.2.1