Re: [PATCH] powerpc/oprofile: Fix error in oprofile power7_marked_instr_event() function
From: Paul Mackerras <hidden>
Date: 2013-01-05 00:55:50
On Thu, Nov 29, 2012 at 08:42:03AM -0800, Carl E. Love wrote:
quoted hunk ↗ jump to hunk
powerpc/oprofile: Fix error in oprofile power7_marked_instr_event() function The calculation for the left shift of the mask OPROFILE_PM_PMCSEL_MSK has an error. The calculation is should be to shift left by (max_cntrs - cntr) times the width of the pmsel field width. However, the #define OPROFILE_MAX_PMC_NUM was used instead of OPROFILE_PMSEL_FIELD_WIDTH. This patch fixes the calculation. Signed-off-by: Carl Love <redacted> --- arch/powerpc/oprofile/op_model_power4.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)diff --git a/arch/powerpc/oprofile/op_model_power4.c b/arch/powerpc/oprofile/op_model_power4.c index 315f949..f444b94 100644 --- a/arch/powerpc/oprofile/op_model_power4.c +++ b/arch/powerpc/oprofile/op_model_power4.c@@ -52,7 +52,7 @@ static int power7_marked_instr_event(u64 mmcr1) for (pmc = 0; pmc < 4; pmc++) { psel = mmcr1 & (OPROFILE_PM_PMCSEL_MSK << (OPROFILE_MAX_PMC_NUM - pmc) - * OPROFILE_MAX_PMC_NUM); + * OPROFILE_PMSEL_FIELD_WIDTH); psel = (psel >> ((OPROFILE_MAX_PMC_NUM - pmc) * OPROFILE_PMSEL_FIELD_WIDTH)) & ~1ULL;
Apart from the fact that those two statements would be simpler and better as: psel = mmcr1 >> ((OPROFILE_MAX_PMC_NUM - pmc) * OPROFILE_PMSEL_FIELD_WIDTH); psel &= OPROFILE_PM_PMCSEL_MSK & ~1ULL; the change looks correct, so: Acked-by: Paul Mackerras <redacted>