From c410352699e2a1adc77969f19eb63030e610d048 Mon Sep 17 00:00:00 2001 From: Deng-Cheng Zhu Date: Thu, 29 May 2014 12:26:45 -0700 Subject: [PATCH] MIPS: math-emu: Add IEEE754 exception statistics to debugfs Sometimes it's useful to let the user, while doing performance research, know what in the IEEE754 exceptions has caused many times of FP emulation when running a specific application. This patch adds 5 more files to /sys/kernel/debug/mips/fpuemustats/, whose filenames begin with "ieee754". These stats are in addition to the existing cp1ops, cp1xops, errors, loads and stores, which may not be useful in understanding the reasons of ieee754 exceptions. [ralf@linux-mips.org: Fixed reject due to other changes to the kernel FP assist software.] Signed-off-by: Deng-Cheng Zhu Cc: linux-mips@linux-mips.org Cc: Steven.Hill@imgtec.com Cc: james.hogan@imgtec.com Patchwork: http://patchwork.linux-mips.org/patch/7044/ Signed-off-by: Ralf Baechle --- arch/mips/include/asm/fpu_emulator.h | 5 ++++ arch/mips/math-emu/cp1emu.c | 36 +++++++++++++++++++++------- arch/mips/math-emu/me-debugfs.c | 5 ++++ 3 files changed, 37 insertions(+), 9 deletions(-) diff --git a/arch/mips/include/asm/fpu_emulator.h b/arch/mips/include/asm/fpu_emulator.h index f761719eab65..0195745b4b1b 100644 --- a/arch/mips/include/asm/fpu_emulator.h +++ b/arch/mips/include/asm/fpu_emulator.h @@ -39,6 +39,11 @@ struct mips_fpu_emulator_stats { local_t cp1ops; local_t cp1xops; local_t errors; + local_t ieee754_inexact; + local_t ieee754_underflow; + local_t ieee754_overflow; + local_t ieee754_zerodiv; + local_t ieee754_invalidop; }; DECLARE_PER_CPU(struct mips_fpu_emulator_stats, fpuemustats); diff --git a/arch/mips/math-emu/cp1emu.c b/arch/mips/math-emu/cp1emu.c index 08e6a74fbc95..cdfed285c244 100644 --- a/arch/mips/math-emu/cp1emu.c +++ b/arch/mips/math-emu/cp1emu.c @@ -1234,14 +1234,22 @@ static int fpux_emu(struct pt_regs *xcp, struct mips_fpu_struct *ctx, SPTOREG(fd, MIPSInst_FD(ir)); copcsr: - if (ieee754_cxtest(IEEE754_INEXACT)) + if (ieee754_cxtest(IEEE754_INEXACT)) { + MIPS_FPU_EMU_INC_STATS(ieee754_inexact); rcsr |= FPU_CSR_INE_X | FPU_CSR_INE_S; - if (ieee754_cxtest(IEEE754_UNDERFLOW)) + } + if (ieee754_cxtest(IEEE754_UNDERFLOW)) { + MIPS_FPU_EMU_INC_STATS(ieee754_underflow); rcsr |= FPU_CSR_UDF_X | FPU_CSR_UDF_S; - if (ieee754_cxtest(IEEE754_OVERFLOW)) + } + if (ieee754_cxtest(IEEE754_OVERFLOW)) { + MIPS_FPU_EMU_INC_STATS(ieee754_overflow); rcsr |= FPU_CSR_OVF_X | FPU_CSR_OVF_S; - if (ieee754_cxtest(IEEE754_INVALID_OPERATION)) + } + if (ieee754_cxtest(IEEE754_INVALID_OPERATION)) { + MIPS_FPU_EMU_INC_STATS(ieee754_invalidop); rcsr |= FPU_CSR_INV_X | FPU_CSR_INV_S; + } ctx->fcr31 = (ctx->fcr31 & ~FPU_CSR_ALL_X) | rcsr; if ((ctx->fcr31 >> 5) & ctx->fcr31 & FPU_CSR_ALL_E) { @@ -1468,16 +1476,26 @@ scopuop: rv.s = (*handler.u) (fs); goto copcsr; copcsr: - if (ieee754_cxtest(IEEE754_INEXACT)) + if (ieee754_cxtest(IEEE754_INEXACT)) { + MIPS_FPU_EMU_INC_STATS(ieee754_inexact); rcsr |= FPU_CSR_INE_X | FPU_CSR_INE_S; - if (ieee754_cxtest(IEEE754_UNDERFLOW)) + } + if (ieee754_cxtest(IEEE754_UNDERFLOW)) { + MIPS_FPU_EMU_INC_STATS(ieee754_underflow); rcsr |= FPU_CSR_UDF_X | FPU_CSR_UDF_S; - if (ieee754_cxtest(IEEE754_OVERFLOW)) + } + if (ieee754_cxtest(IEEE754_OVERFLOW)) { + MIPS_FPU_EMU_INC_STATS(ieee754_overflow); rcsr |= FPU_CSR_OVF_X | FPU_CSR_OVF_S; - if (ieee754_cxtest(IEEE754_ZERO_DIVIDE)) + } + if (ieee754_cxtest(IEEE754_ZERO_DIVIDE)) { + MIPS_FPU_EMU_INC_STATS(ieee754_zerodiv); rcsr |= FPU_CSR_DIV_X | FPU_CSR_DIV_S; - if (ieee754_cxtest(IEEE754_INVALID_OPERATION)) + } + if (ieee754_cxtest(IEEE754_INVALID_OPERATION)) { + MIPS_FPU_EMU_INC_STATS(ieee754_invalidop); rcsr |= FPU_CSR_INV_X | FPU_CSR_INV_S; + } break; /* unary conv ops */ diff --git a/arch/mips/math-emu/me-debugfs.c b/arch/mips/math-emu/me-debugfs.c index 95ed9f9bd2b0..becdd63e14a9 100644 --- a/arch/mips/math-emu/me-debugfs.c +++ b/arch/mips/math-emu/me-debugfs.c @@ -56,6 +56,11 @@ do { \ FPU_STAT_CREATE(cp1ops); FPU_STAT_CREATE(cp1xops); FPU_STAT_CREATE(errors); + FPU_STAT_CREATE(ieee754_inexact); + FPU_STAT_CREATE(ieee754_underflow); + FPU_STAT_CREATE(ieee754_overflow); + FPU_STAT_CREATE(ieee754_zerodiv); + FPU_STAT_CREATE(ieee754_invalidop); return 0; }