Re: [PATCH] perf/x86/intel/uncore: Constify struct

From: Liang, Kan
Date: Mon Jul 15 2024 - 09:46:23 EST




On 2024-07-14 8:40 a.m., Christophe JAILLET wrote:
> 'struct freerunning_counters' are not modified in these drivers.
>
> Constifying this structure moves some data to a read-only section, so
> increase overall security.
>
> On a x86_64, with allmodconfig:
> Before:
> ======
> text data bss dec hex filename
> 79637 71836 16 151489 24fc1 arch/x86/events/intel/uncore_snbep.o
> 24000 13628 0 37628 92fc arch/x86/events/intel/uncore_snb.o
>
> After:
> =====
> text data bss dec hex filename
> 80309 71196 16 151521 24fe1 arch/x86/events/intel/uncore_snbep.o
> 24448 13180 0 37628 92fc arch/x86/events/intel/uncore_snb.o
>
> Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>

Reviewed-by: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>

Thanks,
Kan

> ---
> Compile tested-only.
> ---
> arch/x86/events/intel/uncore.h | 2 +-
> arch/x86/events/intel/uncore_snb.c | 8 ++++----
> arch/x86/events/intel/uncore_snbep.c | 16 ++++++++--------
> 3 files changed, 13 insertions(+), 13 deletions(-)
>
> diff --git a/arch/x86/events/intel/uncore.h b/arch/x86/events/intel/uncore.h
> index 027ef292c602..b7cdf9b8e88a 100644
> --- a/arch/x86/events/intel/uncore.h
> +++ b/arch/x86/events/intel/uncore.h
> @@ -80,7 +80,7 @@ struct intel_uncore_type {
> struct intel_uncore_pmu *pmus;
> struct intel_uncore_ops *ops;
> struct uncore_event_desc *event_descs;
> - struct freerunning_counters *freerunning;
> + const struct freerunning_counters *freerunning;
> const struct attribute_group *attr_groups[4];
> const struct attribute_group **attr_update;
> struct pmu *pmu; /* for custom pmu ops */
> diff --git a/arch/x86/events/intel/uncore_snb.c b/arch/x86/events/intel/uncore_snb.c
> index 9462fd9f3b7a..001ba9230722 100644
> --- a/arch/x86/events/intel/uncore_snb.c
> +++ b/arch/x86/events/intel/uncore_snb.c
> @@ -804,7 +804,7 @@ enum perf_snb_uncore_imc_freerunning_types {
> SNB_PCI_UNCORE_IMC_FREERUNNING_TYPE_MAX,
> };
>
> -static struct freerunning_counters snb_uncore_imc_freerunning[] = {
> +static const struct freerunning_counters snb_uncore_imc_freerunning[] = {
> [SNB_PCI_UNCORE_IMC_DATA_READS] = { SNB_UNCORE_PCI_IMC_DATA_READS_BASE,
> 0x0, 0x0, 1, 32 },
> [SNB_PCI_UNCORE_IMC_DATA_WRITES] = { SNB_UNCORE_PCI_IMC_DATA_WRITES_BASE,
> @@ -1435,13 +1435,13 @@ enum perf_tgl_uncore_imc_freerunning_types {
> TGL_MMIO_UNCORE_IMC_FREERUNNING_TYPE_MAX
> };
>
> -static struct freerunning_counters tgl_l_uncore_imc_freerunning[] = {
> +static const struct freerunning_counters tgl_l_uncore_imc_freerunning[] = {
> [TGL_MMIO_UNCORE_IMC_DATA_TOTAL] = { 0x5040, 0x0, 0x0, 1, 64 },
> [TGL_MMIO_UNCORE_IMC_DATA_READ] = { 0x5058, 0x0, 0x0, 1, 64 },
> [TGL_MMIO_UNCORE_IMC_DATA_WRITE] = { 0x50A0, 0x0, 0x0, 1, 64 },
> };
>
> -static struct freerunning_counters tgl_uncore_imc_freerunning[] = {
> +static const struct freerunning_counters tgl_uncore_imc_freerunning[] = {
> [TGL_MMIO_UNCORE_IMC_DATA_TOTAL] = { 0xd840, 0x0, 0x0, 1, 64 },
> [TGL_MMIO_UNCORE_IMC_DATA_READ] = { 0xd858, 0x0, 0x0, 1, 64 },
> [TGL_MMIO_UNCORE_IMC_DATA_WRITE] = { 0xd8A0, 0x0, 0x0, 1, 64 },
> @@ -1661,7 +1661,7 @@ enum perf_adl_uncore_imc_freerunning_types {
> ADL_MMIO_UNCORE_IMC_FREERUNNING_TYPE_MAX
> };
>
> -static struct freerunning_counters adl_uncore_imc_freerunning[] = {
> +static const struct freerunning_counters adl_uncore_imc_freerunning[] = {
> [ADL_MMIO_UNCORE_IMC_DATA_TOTAL] = { 0x40, 0x0, 0x0, 1, 64 },
> [ADL_MMIO_UNCORE_IMC_DATA_READ] = { 0x58, 0x0, 0x0, 1, 64 },
> [ADL_MMIO_UNCORE_IMC_DATA_WRITE] = { 0xA0, 0x0, 0x0, 1, 64 },
> diff --git a/arch/x86/events/intel/uncore_snbep.c b/arch/x86/events/intel/uncore_snbep.c
> index ca98744343b8..a88343bbd6a6 100644
> --- a/arch/x86/events/intel/uncore_snbep.c
> +++ b/arch/x86/events/intel/uncore_snbep.c
> @@ -4042,7 +4042,7 @@ enum perf_uncore_iio_freerunning_type_id {
> };
>
>
> -static struct freerunning_counters skx_iio_freerunning[] = {
> +static const struct freerunning_counters skx_iio_freerunning[] = {
> [SKX_IIO_MSR_IOCLK] = { 0xa45, 0x1, 0x20, 1, 36 },
> [SKX_IIO_MSR_BW] = { 0xb00, 0x1, 0x10, 8, 36 },
> [SKX_IIO_MSR_UTIL] = { 0xb08, 0x1, 0x10, 8, 36 },
> @@ -4881,7 +4881,7 @@ enum perf_uncore_snr_iio_freerunning_type_id {
> SNR_IIO_FREERUNNING_TYPE_MAX,
> };
>
> -static struct freerunning_counters snr_iio_freerunning[] = {
> +static const struct freerunning_counters snr_iio_freerunning[] = {
> [SNR_IIO_MSR_IOCLK] = { 0x1eac, 0x1, 0x10, 1, 48 },
> [SNR_IIO_MSR_BW_IN] = { 0x1f00, 0x1, 0x10, 8, 48 },
> };
> @@ -5238,7 +5238,7 @@ enum perf_uncore_snr_imc_freerunning_type_id {
> SNR_IMC_FREERUNNING_TYPE_MAX,
> };
>
> -static struct freerunning_counters snr_imc_freerunning[] = {
> +static const struct freerunning_counters snr_imc_freerunning[] = {
> [SNR_IMC_DCLK] = { 0x22b0, 0x0, 0, 1, 48 },
> [SNR_IMC_DDR] = { 0x2290, 0x8, 0, 2, 48 },
> };
> @@ -5480,7 +5480,7 @@ static unsigned icx_iio_bw_freerunning_box_offsets[] = {
> 0x0, 0x10, 0x20, 0x90, 0xa0, 0xb0,
> };
>
> -static struct freerunning_counters icx_iio_freerunning[] = {
> +static const struct freerunning_counters icx_iio_freerunning[] = {
> [ICX_IIO_MSR_IOCLK] = { 0xa55, 0x1, 0x20, 1, 48, icx_iio_clk_freerunning_box_offsets },
> [ICX_IIO_MSR_BW_IN] = { 0xaa0, 0x1, 0x10, 8, 48, icx_iio_bw_freerunning_box_offsets },
> };
> @@ -5838,7 +5838,7 @@ enum perf_uncore_icx_imc_freerunning_type_id {
> ICX_IMC_FREERUNNING_TYPE_MAX,
> };
>
> -static struct freerunning_counters icx_imc_freerunning[] = {
> +static const struct freerunning_counters icx_imc_freerunning[] = {
> [ICX_IMC_DCLK] = { 0x22b0, 0x0, 0, 1, 48 },
> [ICX_IMC_DDR] = { 0x2290, 0x8, 0, 2, 48 },
> [ICX_IMC_DDRT] = { 0x22a0, 0x8, 0, 2, 48 },
> @@ -6314,7 +6314,7 @@ enum perf_uncore_spr_iio_freerunning_type_id {
> SPR_IIO_FREERUNNING_TYPE_MAX,
> };
>
> -static struct freerunning_counters spr_iio_freerunning[] = {
> +static const struct freerunning_counters spr_iio_freerunning[] = {
> [SPR_IIO_MSR_IOCLK] = { 0x340e, 0x1, 0x10, 1, 48 },
> [SPR_IIO_MSR_BW_IN] = { 0x3800, 0x1, 0x10, 8, 48 },
> [SPR_IIO_MSR_BW_OUT] = { 0x3808, 0x1, 0x10, 8, 48 },
> @@ -6393,7 +6393,7 @@ enum perf_uncore_spr_imc_freerunning_type_id {
> SPR_IMC_FREERUNNING_TYPE_MAX,
> };
>
> -static struct freerunning_counters spr_imc_freerunning[] = {
> +static const struct freerunning_counters spr_imc_freerunning[] = {
> [SPR_IMC_DCLK] = { 0x22b0, 0x0, 0, 1, 48 },
> [SPR_IMC_PQ_CYCLES] = { 0x2318, 0x8, 0, 2, 48 },
> };
> @@ -6744,7 +6744,7 @@ static struct intel_uncore_type *gnr_uncores[UNCORE_GNR_NUM_UNCORE_TYPES] = {
> NULL,
> };
>
> -static struct freerunning_counters gnr_iio_freerunning[] = {
> +static const struct freerunning_counters gnr_iio_freerunning[] = {
> [SPR_IIO_MSR_IOCLK] = { 0x290e, 0x01, 0x10, 1, 48 },
> [SPR_IIO_MSR_BW_IN] = { 0x360e, 0x10, 0x80, 8, 48 },
> [SPR_IIO_MSR_BW_OUT] = { 0x2e0e, 0x10, 0x80, 8, 48 },