lkml.org 
[lkml]   [2012]   [Jul]   [26]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 01/17] perf: Unified API to record selective sets of arch registers
Em Sun, Jul 22, 2012 at 02:14:24PM +0200, Jiri Olsa escreveu:
> This brings a new API to help the selective dump of registers on
> event sampling, and its implementation for x86 arch.
>
> Added HAVE_PERF_REGS config option to determine if the architecture
> provides perf registers ABI.
>
> The information about desired registers will be passed in u64 mask.
> It's up to the architecture to map the registers into the mask bits.
>
> For the x86 arch implementation, both 32 and 64 bit registers
> bits are defined within single enum to ensure 64 bit system can
> provide register dump for compat task if needed in the future.


Anton, Paul, Ben,

Does this look OK for PPC?

- Arnaldo

> Signed-off-by: Jiri Olsa <jolsa@redhat.com>
> Original-patch-by: Frederic Weisbecker <fweisbec@gmail.com>
> ---
> arch/Kconfig | 6 +++
> arch/x86/Kconfig | 1 +
> arch/x86/include/asm/perf_regs.h | 33 ++++++++++++++
> arch/x86/kernel/Makefile | 2 +
> arch/x86/kernel/perf_regs.c | 90 ++++++++++++++++++++++++++++++++++++++
> include/linux/perf_regs.h | 19 ++++++++
> 6 files changed, 151 insertions(+), 0 deletions(-)
> create mode 100644 arch/x86/include/asm/perf_regs.h
> create mode 100644 arch/x86/kernel/perf_regs.c
> create mode 100644 include/linux/perf_regs.h
>
> diff --git a/arch/Kconfig b/arch/Kconfig
> index 8c3d957..32f4873 100644
> --- a/arch/Kconfig
> +++ b/arch/Kconfig
> @@ -222,6 +222,12 @@ config HAVE_PERF_EVENTS_NMI
> subsystem. Also has support for calculating CPU cycle events
> to determine how many clock cycles in a given period.
>
> +config HAVE_PERF_REGS
> + bool
> + help
> + Support selective register dumps for perf events. This includes
> + bit-mapping of each registers and a unique architecture id.
> +
> config HAVE_ARCH_JUMP_LABEL
> bool
>
> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> index 94de2c5..acebbd6 100644
> --- a/arch/x86/Kconfig
> +++ b/arch/x86/Kconfig
> @@ -60,6 +60,7 @@ config X86
> select HAVE_MIXED_BREAKPOINTS_REGS
> select PERF_EVENTS
> select HAVE_PERF_EVENTS_NMI
> + select HAVE_PERF_REGS
> select ANON_INODES
> select HAVE_ALIGNED_STRUCT_PAGE if SLUB && !M386
> select HAVE_CMPXCHG_LOCAL if !M386
> diff --git a/arch/x86/include/asm/perf_regs.h b/arch/x86/include/asm/perf_regs.h
> new file mode 100644
> index 0000000..3f2207b
> --- /dev/null
> +++ b/arch/x86/include/asm/perf_regs.h
> @@ -0,0 +1,33 @@
> +#ifndef _ASM_X86_PERF_REGS_H
> +#define _ASM_X86_PERF_REGS_H
> +
> +enum perf_event_x86_regs {
> + PERF_REG_X86_AX,
> + PERF_REG_X86_BX,
> + PERF_REG_X86_CX,
> + PERF_REG_X86_DX,
> + PERF_REG_X86_SI,
> + PERF_REG_X86_DI,
> + PERF_REG_X86_BP,
> + PERF_REG_X86_SP,
> + PERF_REG_X86_IP,
> + PERF_REG_X86_FLAGS,
> + PERF_REG_X86_CS,
> + PERF_REG_X86_SS,
> + PERF_REG_X86_DS,
> + PERF_REG_X86_ES,
> + PERF_REG_X86_FS,
> + PERF_REG_X86_GS,
> + PERF_REG_X86_R8,
> + PERF_REG_X86_R9,
> + PERF_REG_X86_R10,
> + PERF_REG_X86_R11,
> + PERF_REG_X86_R12,
> + PERF_REG_X86_R13,
> + PERF_REG_X86_R14,
> + PERF_REG_X86_R15,
> +
> + PERF_REG_X86_32_MAX = PERF_REG_X86_GS + 1,
> + PERF_REG_X86_64_MAX = PERF_REG_X86_R15 + 1,
> +};
> +#endif /* _ASM_X86_PERF_REGS_H */
> diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
> index 8215e56..8d7a619 100644
> --- a/arch/x86/kernel/Makefile
> +++ b/arch/x86/kernel/Makefile
> @@ -100,6 +100,8 @@ obj-$(CONFIG_SWIOTLB) += pci-swiotlb.o
> obj-$(CONFIG_OF) += devicetree.o
> obj-$(CONFIG_UPROBES) += uprobes.o
>
> +obj-$(CONFIG_PERF_EVENTS) += perf_regs.o
> +
> ###
> # 64 bit specific files
> ifeq ($(CONFIG_X86_64),y)
> diff --git a/arch/x86/kernel/perf_regs.c b/arch/x86/kernel/perf_regs.c
> new file mode 100644
> index 0000000..c00c92a
> --- /dev/null
> +++ b/arch/x86/kernel/perf_regs.c
> @@ -0,0 +1,90 @@
> +
> +#include <linux/kernel.h>
> +#include <linux/bug.h>
> +#include <linux/stddef.h>
> +#include <asm/perf_regs.h>
> +#include <asm/ptrace.h>
> +
> +#ifdef CONFIG_X86_32
> +#define PERF_REG_X86_MAX PERF_REG_X86_32_MAX
> +#else
> +#define PERF_REG_X86_MAX PERF_REG_X86_64_MAX
> +#endif
> +
> +#define PT_REGS_OFFSET(id, r) [id] = offsetof(struct pt_regs, r)
> +
> +static unsigned int pt_regs_offset[PERF_REG_X86_MAX] = {
> + PT_REGS_OFFSET(PERF_REG_X86_AX, ax),
> + PT_REGS_OFFSET(PERF_REG_X86_BX, bx),
> + PT_REGS_OFFSET(PERF_REG_X86_CX, cx),
> + PT_REGS_OFFSET(PERF_REG_X86_DX, dx),
> + PT_REGS_OFFSET(PERF_REG_X86_SI, si),
> + PT_REGS_OFFSET(PERF_REG_X86_DI, di),
> + PT_REGS_OFFSET(PERF_REG_X86_BP, bp),
> + PT_REGS_OFFSET(PERF_REG_X86_SP, sp),
> + PT_REGS_OFFSET(PERF_REG_X86_IP, ip),
> + PT_REGS_OFFSET(PERF_REG_X86_FLAGS, flags),
> + PT_REGS_OFFSET(PERF_REG_X86_CS, cs),
> + PT_REGS_OFFSET(PERF_REG_X86_SS, ss),
> +#ifdef CONFIG_X86_32
> + PT_REGS_OFFSET(PERF_REG_X86_DS, ds),
> + PT_REGS_OFFSET(PERF_REG_X86_ES, es),
> + PT_REGS_OFFSET(PERF_REG_X86_FS, fs),
> + PT_REGS_OFFSET(PERF_REG_X86_GS, gs),
> +#else
> + /*
> + * The pt_regs struct does not store
> + * ds, es, fs, gs in 64 bit mode.
> + */
> + (unsigned int) -1,
> + (unsigned int) -1,
> + (unsigned int) -1,
> + (unsigned int) -1,
> +#endif
> +#ifdef CONFIG_X86_64
> + PT_REGS_OFFSET(PERF_REG_X86_R8, r8),
> + PT_REGS_OFFSET(PERF_REG_X86_R9, r9),
> + PT_REGS_OFFSET(PERF_REG_X86_R10, r10),
> + PT_REGS_OFFSET(PERF_REG_X86_R11, r11),
> + PT_REGS_OFFSET(PERF_REG_X86_R12, r12),
> + PT_REGS_OFFSET(PERF_REG_X86_R13, r13),
> + PT_REGS_OFFSET(PERF_REG_X86_R14, r14),
> + PT_REGS_OFFSET(PERF_REG_X86_R15, r15),
> +#endif
> +};
> +
> +u64 perf_reg_value(struct pt_regs *regs, int idx)
> +{
> + if (WARN_ON_ONCE(idx > ARRAY_SIZE(pt_regs_offset)))
> + return 0;
> +
> + return regs_get_register(regs, pt_regs_offset[idx]);
> +}
> +
> +#define REG_RESERVED (~((1ULL << PERF_REG_X86_MAX) - 1ULL))
> +
> +#ifdef CONFIG_X86_32
> +int perf_reg_validate(u64 mask)
> +{
> + if (!mask || mask & REG_RESERVED)
> + return -EINVAL;
> +
> + return 0;
> +}
> +#else /* CONFIG_X86_64 */
> +#define REG_NOSUPPORT ((1ULL << PERF_REG_X86_DS) | \
> + (1ULL << PERF_REG_X86_ES) | \
> + (1ULL << PERF_REG_X86_FS) | \
> + (1ULL << PERF_REG_X86_GS))
> +
> +int perf_reg_validate(u64 mask)
> +{
> + if (!mask || mask & REG_RESERVED)
> + return -EINVAL;
> +
> + if (mask & REG_NOSUPPORT)
> + return -EINVAL;
> +
> + return 0;
> +}
> +#endif /* CONFIG_X86_32 */
> diff --git a/include/linux/perf_regs.h b/include/linux/perf_regs.h
> new file mode 100644
> index 0000000..a2f1a98
> --- /dev/null
> +++ b/include/linux/perf_regs.h
> @@ -0,0 +1,19 @@
> +#ifndef _LINUX_PERF_REGS_H
> +#define _LINUX_PERF_REGS_H
> +
> +#ifdef CONFIG_HAVE_PERF_REGS
> +#include <asm/perf_regs.h>
> +u64 perf_reg_value(struct pt_regs *regs, int idx);
> +int perf_reg_validate(u64 mask);
> +#else
> +static inline u64 perf_reg_value(struct pt_regs *regs, int idx)
> +{
> + return 0;
> +}
> +
> +static inline int perf_reg_validate(u64 mask)
> +{
> + return mask ? -ENOSYS : 0;
> +}
> +#endif /* CONFIG_HAVE_PERF_REGS */
> +#endif /* _LINUX_PERF_REGS_H */
> --
> 1.7.7.6


\
 
 \ /
  Last update: 2012-07-26 21:01    [W:0.209 / U:1.508 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site