From 4018994f3d8785275ef0e7391b75c3462c029e56 Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Tue, 7 Aug 2012 15:20:37 +0200 Subject: perf: Add ability to attach user level registers dump to sample Introducing PERF_SAMPLE_REGS_USER sample type bit to trigger the dump of user level registers on sample. Registers we want to dump are specified by sample_regs_user bitmask. Only user level registers are dumped at the moment. Meaning the register values of the user space context as it was before the user entered the kernel for whatever reason (syscall, irq, exception, or a PMI happening in userspace). The layout of the sample_regs_user bitmap is described in asm/perf_regs.h for archs that support register dump. This is going to be useful to bring Dwarf CFI based stack unwinding on top of samples. Original-patch-by: Frederic Weisbecker [ Dump registers ABI specification. ] Signed-off-by: Jiri Olsa Suggested-by: Stephane Eranian Cc: "Frank Ch. Eigler" Cc: Arun Sharma Cc: Benjamin Redelings Cc: Corey Ashford Cc: Cyrill Gorcunov Cc: Frank Ch. Eigler Cc: Frederic Weisbecker Cc: Ingo Molnar Cc: Masami Hiramatsu Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Robert Richter Cc: Stephane Eranian Cc: Tom Zanussi Cc: Ulrich Drepper Link: http://lkml.kernel.org/r/1344345647-11536-3-git-send-email-jolsa@redhat.com Signed-off-by: Arnaldo Carvalho de Melo --- include/linux/perf_event.h | 35 ++++++++++++++++++++++++++++++++--- 1 file changed, 32 insertions(+), 3 deletions(-) (limited to 'include/linux/perf_event.h') diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h index 7602ccb3f40e..3d4d84745f07 100644 --- a/include/linux/perf_event.h +++ b/include/linux/perf_event.h @@ -130,8 +130,9 @@ enum perf_event_sample_format { PERF_SAMPLE_STREAM_ID = 1U << 9, PERF_SAMPLE_RAW = 1U << 10, PERF_SAMPLE_BRANCH_STACK = 1U << 11, + PERF_SAMPLE_REGS_USER = 1U << 12, - PERF_SAMPLE_MAX = 1U << 12, /* non-ABI */ + PERF_SAMPLE_MAX = 1U << 13, /* non-ABI */ }; /* @@ -162,6 +163,15 @@ enum perf_branch_sample_type { PERF_SAMPLE_BRANCH_KERNEL|\ PERF_SAMPLE_BRANCH_HV) +/* + * Values to determine ABI of the registers dump. + */ +enum perf_sample_regs_abi { + PERF_SAMPLE_REGS_ABI_NONE = 0, + PERF_SAMPLE_REGS_ABI_32 = 1, + PERF_SAMPLE_REGS_ABI_64 = 2, +}; + /* * The format of the data returned by read() on a perf event fd, * as specified by attr.read_format: @@ -194,6 +204,7 @@ enum perf_event_read_format { #define PERF_ATTR_SIZE_VER0 64 /* sizeof first published struct */ #define PERF_ATTR_SIZE_VER1 72 /* add: config2 */ #define PERF_ATTR_SIZE_VER2 80 /* add: branch_sample_type */ +#define PERF_ATTR_SIZE_VER3 88 /* add: sample_regs_user */ /* * Hardware event_id to monitor via a performance monitoring event: @@ -271,7 +282,13 @@ struct perf_event_attr { __u64 bp_len; __u64 config2; /* extension of config1 */ }; - __u64 branch_sample_type; /* enum branch_sample_type */ + __u64 branch_sample_type; /* enum perf_branch_sample_type */ + + /* + * Defines set of user regs to dump on samples. + * See asm/perf_regs.h for details. + */ + __u64 sample_regs_user; }; /* @@ -548,6 +565,9 @@ enum perf_event_type { * char data[size];}&& PERF_SAMPLE_RAW * * { u64 from, to, flags } lbr[nr];} && PERF_SAMPLE_BRANCH_STACK + * + * { u64 abi; # enum perf_sample_regs_abi + * u64 regs[weight(mask)]; } && PERF_SAMPLE_REGS_USER * }; */ PERF_RECORD_SAMPLE = 9, @@ -609,6 +629,7 @@ struct perf_guest_info_callbacks { #include #include #include +#include #include struct perf_callchain_entry { @@ -654,6 +675,11 @@ struct perf_branch_stack { struct perf_branch_entry entries[0]; }; +struct perf_regs_user { + __u64 abi; + struct pt_regs *regs; +}; + struct task_struct; /* @@ -1133,6 +1159,7 @@ struct perf_sample_data { struct perf_callchain_entry *callchain; struct perf_raw_record *raw; struct perf_branch_stack *br_stack; + struct perf_regs_user regs_user; }; static inline void perf_sample_data_init(struct perf_sample_data *data, @@ -1142,7 +1169,9 @@ static inline void perf_sample_data_init(struct perf_sample_data *data, data->addr = addr; data->raw = NULL; data->br_stack = NULL; - data->period = period; + data->period = period; + data->regs_user.abi = PERF_SAMPLE_REGS_ABI_NONE; + data->regs_user.regs = NULL; } extern void perf_output_sample(struct perf_output_handle *handle, -- cgit v1.2.3 From 91d7753a45f8525dc75b6be01e427dc1c378dc16 Mon Sep 17 00:00:00 2001 From: Frederic Weisbecker Date: Tue, 7 Aug 2012 15:20:38 +0200 Subject: perf: Factor __output_copy to be usable with specific copy function Adding a generic way to use __output_copy function with specific copy function via DEFINE_PERF_OUTPUT_COPY macro. Using this to add new __output_copy_user function, that provides output copy from user pointers. For x86 the copy_from_user_nmi function is used and __copy_from_user_inatomic for the rest of the architectures. This new function will be used in user stack dump on sample, coming in next patches. Signed-off-by: Jiri Olsa Cc: "Frank Ch. Eigler" Cc: Arun Sharma Cc: Benjamin Redelings Cc: Corey Ashford Cc: Cyrill Gorcunov Cc: Frank Ch. Eigler Cc: Ingo Molnar Cc: Jiri Olsa Cc: Masami Hiramatsu Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Robert Richter Cc: Stephane Eranian Cc: Tom Zanussi Cc: Ulrich Drepper Link: http://lkml.kernel.org/r/1344345647-11536-4-git-send-email-jolsa@redhat.com Signed-off-by: Frederic Weisbecker Signed-off-by: Arnaldo Carvalho de Melo --- arch/x86/include/asm/perf_event.h | 2 ++ include/linux/perf_event.h | 2 +- kernel/events/internal.h | 62 ++++++++++++++++++++++++++------------- kernel/events/ring_buffer.c | 4 +-- 4 files changed, 46 insertions(+), 24 deletions(-) (limited to 'include/linux/perf_event.h') diff --git a/arch/x86/include/asm/perf_event.h b/arch/x86/include/asm/perf_event.h index cb4e43bce98a..4fabcdf1cfa7 100644 --- a/arch/x86/include/asm/perf_event.h +++ b/arch/x86/include/asm/perf_event.h @@ -262,4 +262,6 @@ static inline void perf_check_microcode(void) { } static inline void amd_pmu_disable_virt(void) { } #endif +#define arch_perf_out_copy_user copy_from_user_nmi + #endif /* _ASM_X86_PERF_EVENT_H */ diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h index 3d4d84745f07..d41394a1af36 100644 --- a/include/linux/perf_event.h +++ b/include/linux/perf_event.h @@ -1319,7 +1319,7 @@ static inline bool has_branch_stack(struct perf_event *event) extern int perf_output_begin(struct perf_output_handle *handle, struct perf_event *event, unsigned int size); extern void perf_output_end(struct perf_output_handle *handle); -extern void perf_output_copy(struct perf_output_handle *handle, +extern unsigned int perf_output_copy(struct perf_output_handle *handle, const void *buf, unsigned int len); extern int perf_swevent_get_recursion_context(void); extern void perf_swevent_put_recursion_context(int rctx); diff --git a/kernel/events/internal.h b/kernel/events/internal.h index a096c19f2c2a..7fd5408493d2 100644 --- a/kernel/events/internal.h +++ b/kernel/events/internal.h @@ -2,6 +2,7 @@ #define _KERNEL_EVENTS_INTERNAL_H #include +#include /* Buffer handling */ @@ -76,30 +77,49 @@ static inline unsigned long perf_data_size(struct ring_buffer *rb) return rb->nr_pages << (PAGE_SHIFT + page_order(rb)); } -static inline void -__output_copy(struct perf_output_handle *handle, - const void *buf, unsigned int len) +#define DEFINE_OUTPUT_COPY(func_name, memcpy_func) \ +static inline unsigned int \ +func_name(struct perf_output_handle *handle, \ + const void *buf, unsigned int len) \ +{ \ + unsigned long size, written; \ + \ + do { \ + size = min_t(unsigned long, handle->size, len); \ + \ + written = memcpy_func(handle->addr, buf, size); \ + \ + len -= written; \ + handle->addr += written; \ + buf += written; \ + handle->size -= written; \ + if (!handle->size) { \ + struct ring_buffer *rb = handle->rb; \ + \ + handle->page++; \ + handle->page &= rb->nr_pages - 1; \ + handle->addr = rb->data_pages[handle->page]; \ + handle->size = PAGE_SIZE << page_order(rb); \ + } \ + } while (len && written == size); \ + \ + return len; \ +} + +static inline int memcpy_common(void *dst, const void *src, size_t n) { - do { - unsigned long size = min_t(unsigned long, handle->size, len); - - memcpy(handle->addr, buf, size); - - len -= size; - handle->addr += size; - buf += size; - handle->size -= size; - if (!handle->size) { - struct ring_buffer *rb = handle->rb; - - handle->page++; - handle->page &= rb->nr_pages - 1; - handle->addr = rb->data_pages[handle->page]; - handle->size = PAGE_SIZE << page_order(rb); - } - } while (len); + memcpy(dst, src, n); + return n; } +DEFINE_OUTPUT_COPY(__output_copy, memcpy_common) + +#ifndef arch_perf_out_copy_user +#define arch_perf_out_copy_user __copy_from_user_inatomic +#endif + +DEFINE_OUTPUT_COPY(__output_copy_user, arch_perf_out_copy_user) + /* Callchain handling */ extern struct perf_callchain_entry * perf_callchain(struct perf_event *event, struct pt_regs *regs); diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c index 6ddaba43fb7a..b4c2ad3dee7a 100644 --- a/kernel/events/ring_buffer.c +++ b/kernel/events/ring_buffer.c @@ -182,10 +182,10 @@ out: return -ENOSPC; } -void perf_output_copy(struct perf_output_handle *handle, +unsigned int perf_output_copy(struct perf_output_handle *handle, const void *buf, unsigned int len) { - __output_copy(handle, buf, len); + return __output_copy(handle, buf, len); } void perf_output_end(struct perf_output_handle *handle) -- cgit v1.2.3 From 5685e0ff45f5df67e79e9b052b6ffd501ff38c11 Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Tue, 7 Aug 2012 15:20:39 +0200 Subject: perf: Add perf_output_skip function to skip bytes in sample Introducing perf_output_skip function to be able to skip data within the perf ring buffer. When writing data into perf ring buffer we first reserve needed place in ring buffer and then copy the actual data. There's a possibility we won't be able to fill all the reserved size with data, so we need a way to skip the remaining bytes. This is going to be useful when storing the user stack dump, where we might end up with less data than we originally requested. Signed-off-by: Jiri Olsa Acked-by: Frederic Weisbecker Cc: "Frank Ch. Eigler" Cc: Arun Sharma Cc: Benjamin Redelings Cc: Corey Ashford Cc: Cyrill Gorcunov Cc: Frank Ch. Eigler Cc: Frederic Weisbecker Cc: Ingo Molnar Cc: Masami Hiramatsu Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Robert Richter Cc: Stephane Eranian Cc: Tom Zanussi Cc: Ulrich Drepper Link: http://lkml.kernel.org/r/1344345647-11536-5-git-send-email-jolsa@redhat.com Signed-off-by: Arnaldo Carvalho de Melo --- include/linux/perf_event.h | 2 ++ kernel/events/internal.h | 4 ++++ kernel/events/ring_buffer.c | 6 ++++++ 3 files changed, 12 insertions(+) (limited to 'include/linux/perf_event.h') diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h index d41394a1af36..8a73f75beb16 100644 --- a/include/linux/perf_event.h +++ b/include/linux/perf_event.h @@ -1321,6 +1321,8 @@ extern int perf_output_begin(struct perf_output_handle *handle, extern void perf_output_end(struct perf_output_handle *handle); extern unsigned int perf_output_copy(struct perf_output_handle *handle, const void *buf, unsigned int len); +extern unsigned int perf_output_skip(struct perf_output_handle *handle, + unsigned int len); extern int perf_swevent_get_recursion_context(void); extern void perf_swevent_put_recursion_context(int rctx); extern void perf_event_enable(struct perf_event *event); diff --git a/kernel/events/internal.h b/kernel/events/internal.h index 7fd5408493d2..ce7bdfc1d045 100644 --- a/kernel/events/internal.h +++ b/kernel/events/internal.h @@ -114,6 +114,10 @@ static inline int memcpy_common(void *dst, const void *src, size_t n) DEFINE_OUTPUT_COPY(__output_copy, memcpy_common) +#define MEMCPY_SKIP(dst, src, n) (n) + +DEFINE_OUTPUT_COPY(__output_skip, MEMCPY_SKIP) + #ifndef arch_perf_out_copy_user #define arch_perf_out_copy_user __copy_from_user_inatomic #endif diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c index b4c2ad3dee7a..23cb34ff3973 100644 --- a/kernel/events/ring_buffer.c +++ b/kernel/events/ring_buffer.c @@ -188,6 +188,12 @@ unsigned int perf_output_copy(struct perf_output_handle *handle, return __output_copy(handle, buf, len); } +unsigned int perf_output_skip(struct perf_output_handle *handle, + unsigned int len) +{ + return __output_skip(handle, NULL, len); +} + void perf_output_end(struct perf_output_handle *handle) { perf_output_put_handle(handle); -- cgit v1.2.3 From c5ebcedb566ef17bda7b02686e0d658a7bb42ee7 Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Tue, 7 Aug 2012 15:20:40 +0200 Subject: perf: Add ability to attach user stack dump to sample Introducing PERF_SAMPLE_STACK_USER sample type bit to trigger the dump of the user level stack on sample. The size of the dump is specified by sample_stack_user value. Being able to dump parts of the user stack, starting from the stack pointer, will be useful to make a post mortem dwarf CFI based stack unwinding. Added HAVE_PERF_USER_STACK_DUMP config option to determine if the architecture provides user stack dump on perf event samples. This needs access to the user stack pointer which is not unified across architectures. Enabling this for x86 architecture. Signed-off-by: Jiri Olsa Original-patch-by: Frederic Weisbecker Cc: "Frank Ch. Eigler" Cc: Arun Sharma Cc: Benjamin Redelings Cc: Corey Ashford Cc: Cyrill Gorcunov Cc: Frank Ch. Eigler Cc: Frederic Weisbecker Cc: Ingo Molnar Cc: Masami Hiramatsu Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Robert Richter Cc: Stephane Eranian Cc: Tom Zanussi Cc: Ulrich Drepper Link: http://lkml.kernel.org/r/1344345647-11536-6-git-send-email-jolsa@redhat.com Signed-off-by: Arnaldo Carvalho de Melo --- arch/Kconfig | 7 +++ arch/x86/Kconfig | 1 + include/linux/perf_event.h | 18 +++++- kernel/events/core.c | 150 ++++++++++++++++++++++++++++++++++++++++++++- kernel/events/internal.h | 16 +++++ 5 files changed, 190 insertions(+), 2 deletions(-) (limited to 'include/linux/perf_event.h') diff --git a/arch/Kconfig b/arch/Kconfig index 68d827b7ae82..2a83a3f6a615 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -228,6 +228,13 @@ config HAVE_PERF_REGS Support selective register dumps for perf events. This includes bit-mapping of each registers and a unique architecture id. +config HAVE_PERF_USER_STACK_DUMP + bool + help + Support user stack dumps for perf event samples. This needs + access to the user stack pointer which is not unified across + architectures. + config HAVE_ARCH_JUMP_LABEL bool diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 3fab6ec9edc4..a2d19ee750ca 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -61,6 +61,7 @@ config X86 select PERF_EVENTS select HAVE_PERF_EVENTS_NMI select HAVE_PERF_REGS + select HAVE_PERF_USER_STACK_DUMP select ANON_INODES select HAVE_ALIGNED_STRUCT_PAGE if SLUB && !M386 select HAVE_CMPXCHG_LOCAL if !M386 diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h index 8a73f75beb16..d1d25f6a5e24 100644 --- a/include/linux/perf_event.h +++ b/include/linux/perf_event.h @@ -131,8 +131,9 @@ enum perf_event_sample_format { PERF_SAMPLE_RAW = 1U << 10, PERF_SAMPLE_BRANCH_STACK = 1U << 11, PERF_SAMPLE_REGS_USER = 1U << 12, + PERF_SAMPLE_STACK_USER = 1U << 13, - PERF_SAMPLE_MAX = 1U << 13, /* non-ABI */ + PERF_SAMPLE_MAX = 1U << 14, /* non-ABI */ }; /* @@ -205,6 +206,7 @@ enum perf_event_read_format { #define PERF_ATTR_SIZE_VER1 72 /* add: config2 */ #define PERF_ATTR_SIZE_VER2 80 /* add: branch_sample_type */ #define PERF_ATTR_SIZE_VER3 88 /* add: sample_regs_user */ +#define PERF_ATTR_SIZE_VER4 96 /* add: sample_stack_user */ /* * Hardware event_id to monitor via a performance monitoring event: @@ -289,6 +291,14 @@ struct perf_event_attr { * See asm/perf_regs.h for details. */ __u64 sample_regs_user; + + /* + * Defines size of the user stack to dump on samples. + */ + __u32 sample_stack_user; + + /* Align to u64. */ + __u32 __reserved_2; }; /* @@ -568,6 +578,10 @@ enum perf_event_type { * * { u64 abi; # enum perf_sample_regs_abi * u64 regs[weight(mask)]; } && PERF_SAMPLE_REGS_USER + * + * { u64 size; + * char data[size]; + * u64 dyn_size; } && PERF_SAMPLE_STACK_USER * }; */ PERF_RECORD_SAMPLE = 9, @@ -1160,6 +1174,7 @@ struct perf_sample_data { struct perf_raw_record *raw; struct perf_branch_stack *br_stack; struct perf_regs_user regs_user; + u64 stack_user_size; }; static inline void perf_sample_data_init(struct perf_sample_data *data, @@ -1172,6 +1187,7 @@ static inline void perf_sample_data_init(struct perf_sample_data *data, data->period = period; data->regs_user.abi = PERF_SAMPLE_REGS_ABI_NONE; data->regs_user.regs = NULL; + data->stack_user_size = 0; } extern void perf_output_sample(struct perf_output_handle *handle, diff --git a/kernel/events/core.c b/kernel/events/core.c index d3ce97525b9f..2ba890450d15 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -36,6 +36,7 @@ #include #include #include +#include #include "internal.h" @@ -3787,6 +3788,101 @@ static void perf_sample_regs_user(struct perf_regs_user *regs_user, } } +/* + * Get remaining task size from user stack pointer. + * + * It'd be better to take stack vma map and limit this more + * precisly, but there's no way to get it safely under interrupt, + * so using TASK_SIZE as limit. + */ +static u64 perf_ustack_task_size(struct pt_regs *regs) +{ + unsigned long addr = perf_user_stack_pointer(regs); + + if (!addr || addr >= TASK_SIZE) + return 0; + + return TASK_SIZE - addr; +} + +static u16 +perf_sample_ustack_size(u16 stack_size, u16 header_size, + struct pt_regs *regs) +{ + u64 task_size; + + /* No regs, no stack pointer, no dump. */ + if (!regs) + return 0; + + /* + * Check if we fit in with the requested stack size into the: + * - TASK_SIZE + * If we don't, we limit the size to the TASK_SIZE. + * + * - remaining sample size + * If we don't, we customize the stack size to + * fit in to the remaining sample size. + */ + + task_size = min((u64) USHRT_MAX, perf_ustack_task_size(regs)); + stack_size = min(stack_size, (u16) task_size); + + /* Current header size plus static size and dynamic size. */ + header_size += 2 * sizeof(u64); + + /* Do we fit in with the current stack dump size? */ + if ((u16) (header_size + stack_size) < header_size) { + /* + * If we overflow the maximum size for the sample, + * we customize the stack dump size to fit in. + */ + stack_size = USHRT_MAX - header_size - sizeof(u64); + stack_size = round_up(stack_size, sizeof(u64)); + } + + return stack_size; +} + +static void +perf_output_sample_ustack(struct perf_output_handle *handle, u64 dump_size, + struct pt_regs *regs) +{ + /* Case of a kernel thread, nothing to dump */ + if (!regs) { + u64 size = 0; + perf_output_put(handle, size); + } else { + unsigned long sp; + unsigned int rem; + u64 dyn_size; + + /* + * We dump: + * static size + * - the size requested by user or the best one we can fit + * in to the sample max size + * data + * - user stack dump data + * dynamic size + * - the actual dumped size + */ + + /* Static size. */ + perf_output_put(handle, dump_size); + + /* Data. */ + sp = perf_user_stack_pointer(regs); + rem = __output_copy_user(handle, (void *) sp, dump_size); + dyn_size = dump_size - rem; + + perf_output_skip(handle, rem); + + /* Dynamic size. */ + perf_output_put(handle, dyn_size); + } +} + static void __perf_event_header__init_id(struct perf_event_header *header, struct perf_sample_data *data, struct perf_event *event) @@ -4064,6 +4160,11 @@ void perf_output_sample(struct perf_output_handle *handle, mask); } } + + if (sample_type & PERF_SAMPLE_STACK_USER) + perf_output_sample_ustack(handle, + data->stack_user_size, + data->regs_user.regs); } void perf_prepare_sample(struct perf_event_header *header, @@ -4129,6 +4230,35 @@ void perf_prepare_sample(struct perf_event_header *header, header->size += size; } + + if (sample_type & PERF_SAMPLE_STACK_USER) { + /* + * Either we need PERF_SAMPLE_STACK_USER bit to be allways + * processed as the last one or have additional check added + * in case new sample type is added, because we could eat + * up the rest of the sample size. + */ + struct perf_regs_user *uregs = &data->regs_user; + u16 stack_size = event->attr.sample_stack_user; + u16 size = sizeof(u64); + + if (!uregs->abi) + perf_sample_regs_user(uregs, regs); + + stack_size = perf_sample_ustack_size(stack_size, header->size, + uregs->regs); + + /* + * If there is something to dump, add space for the dump + * itself and for the field that tells the dynamic size, + * which is how many have been actually dumped. + */ + if (stack_size) + size += sizeof(u64) + stack_size; + + data->stack_user_size = stack_size; + header->size += size; + } } static void perf_event_output(struct perf_event *event, @@ -6205,8 +6335,26 @@ static int perf_copy_attr(struct perf_event_attr __user *uattr, } } - if (attr->sample_type & PERF_SAMPLE_REGS_USER) + if (attr->sample_type & PERF_SAMPLE_REGS_USER) { ret = perf_reg_validate(attr->sample_regs_user); + if (ret) + return ret; + } + + if (attr->sample_type & PERF_SAMPLE_STACK_USER) { + if (!arch_perf_have_user_stack_dump()) + return -ENOSYS; + + /* + * We have __u32 type for the size, but so far + * we can only use __u16 as maximum due to the + * __u16 sample size limit. + */ + if (attr->sample_stack_user >= USHRT_MAX) + ret = -EINVAL; + else if (!IS_ALIGNED(attr->sample_stack_user, sizeof(u64))) + ret = -EINVAL; + } out: return ret; diff --git a/kernel/events/internal.h b/kernel/events/internal.h index ce7bdfc1d045..d56a64c99a8b 100644 --- a/kernel/events/internal.h +++ b/kernel/events/internal.h @@ -158,4 +158,20 @@ static inline void put_recursion_context(int *recursion, int rctx) recursion[rctx]--; } +#ifdef CONFIG_HAVE_PERF_USER_STACK_DUMP +static inline bool arch_perf_have_user_stack_dump(void) +{ + return true; +} + +#define perf_user_stack_pointer(regs) user_stack_pointer(regs) +#else +static inline bool arch_perf_have_user_stack_dump(void) +{ + return false; +} + +#define perf_user_stack_pointer(regs) 0 +#endif /* CONFIG_HAVE_PERF_USER_STACK_DUMP */ + #endif /* _KERNEL_EVENTS_INTERNAL_H */ -- cgit v1.2.3 From d077526485d5c9b12fe85d0b2b3b7041e6bc5f91 Mon Sep 17 00:00:00 2001 From: Frederic Weisbecker Date: Tue, 7 Aug 2012 15:20:41 +0200 Subject: perf: Add attribute to filter out callchains Introducing following bits to the the perf_event_attr struct: - exclude_callchain_kernel to filter out kernel callchain from the sample dump - exclude_callchain_user to filter out user callchain from the sample dump We need to be able to disable standard user callchain dump when we use the dwarf cfi callchain mode, because frame pointer based user callchains are useless in this mode. Implementing also exclude_callchain_kernel to have complete set of options. Signed-off-by: Jiri Olsa [ Added kernel callchains filtering ] Cc: "Frank Ch. Eigler" Cc: Arun Sharma Cc: Benjamin Redelings Cc: Corey Ashford Cc: Cyrill Gorcunov Cc: Frank Ch. Eigler Cc: Ingo Molnar Cc: Jiri Olsa Cc: Masami Hiramatsu Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Robert Richter Cc: Stephane Eranian Cc: Tom Zanussi Cc: Ulrich Drepper Link: http://lkml.kernel.org/r/1344345647-11536-7-git-send-email-jolsa@redhat.com Signed-off-by: Frederic Weisbecker Signed-off-by: Arnaldo Carvalho de Melo --- include/linux/perf_event.h | 5 ++++- kernel/events/callchain.c | 38 ++++++++++++++++++++++++-------------- 2 files changed, 28 insertions(+), 15 deletions(-) (limited to 'include/linux/perf_event.h') diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h index d1d25f6a5e24..297ca3db6b4a 100644 --- a/include/linux/perf_event.h +++ b/include/linux/perf_event.h @@ -268,7 +268,10 @@ struct perf_event_attr { exclude_host : 1, /* don't count in host */ exclude_guest : 1, /* don't count in guest */ - __reserved_1 : 43; + exclude_callchain_kernel : 1, /* exclude kernel callchains */ + exclude_callchain_user : 1, /* exclude user callchains */ + + __reserved_1 : 41; union { __u32 wakeup_events; /* wakeup every n events */ diff --git a/kernel/events/callchain.c b/kernel/events/callchain.c index 98d4597f43d6..c77206184b8b 100644 --- a/kernel/events/callchain.c +++ b/kernel/events/callchain.c @@ -159,6 +159,11 @@ perf_callchain(struct perf_event *event, struct pt_regs *regs) int rctx; struct perf_callchain_entry *entry; + int kernel = !event->attr.exclude_callchain_kernel; + int user = !event->attr.exclude_callchain_user; + + if (!kernel && !user) + return NULL; entry = get_callchain_entry(&rctx); if (rctx == -1) @@ -169,24 +174,29 @@ perf_callchain(struct perf_event *event, struct pt_regs *regs) entry->nr = 0; - if (!user_mode(regs)) { + if (kernel && !user_mode(regs)) { perf_callchain_store(entry, PERF_CONTEXT_KERNEL); perf_callchain_kernel(entry, regs); - if (current->mm) - regs = task_pt_regs(current); - else - regs = NULL; } - if (regs) { - /* - * Disallow cross-task user callchains. - */ - if (event->ctx->task && event->ctx->task != current) - goto exit_put; - - perf_callchain_store(entry, PERF_CONTEXT_USER); - perf_callchain_user(entry, regs); + if (user) { + if (!user_mode(regs)) { + if (current->mm) + regs = task_pt_regs(current); + else + regs = NULL; + } + + if (regs) { + /* + * Disallow cross-task user callchains. + */ + if (event->ctx->task && event->ctx->task != current) + goto exit_put; + + perf_callchain_store(entry, PERF_CONTEXT_USER); + perf_callchain_user(entry, regs); + } } exit_put: -- cgit v1.2.3 From 1659d129ed014b715b0b2120e6fd929bdd33ed03 Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Wed, 22 Aug 2012 10:35:40 +0200 Subject: perf tools: Keep the perf_event_attr on version 3 Stashing version 4 under version 3 and removing version 4, because both version changes were within single patchset. Reported-by: Peter Zijlstra Signed-off-by: Jiri Olsa Acked-by: Peter Zijlstra Cc: Arun Sharma Cc: Benjamin Redelings Cc: Corey Ashford Cc: Cyrill Gorcunov Cc: Frank Ch. Eigler Cc: Frederic Weisbecker Cc: H. Peter Anvin Cc: Ingo Molnar Cc: Masami Hiramatsu Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Robert Richter Cc: Stephane Eranian Cc: Thomas Gleixner Cc: Tom Zanussi Cc: Ulrich Drepper Link: http://lkml.kernel.org/r/20120822083540.GB1003@krava.brq.redhat.com Signed-off-by: Arnaldo Carvalho de Melo --- include/linux/perf_event.h | 4 ++-- tools/perf/util/header.c | 1 - 2 files changed, 2 insertions(+), 3 deletions(-) (limited to 'include/linux/perf_event.h') diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h index 297ca3db6b4a..28f9cee3fbc3 100644 --- a/include/linux/perf_event.h +++ b/include/linux/perf_event.h @@ -205,8 +205,8 @@ enum perf_event_read_format { #define PERF_ATTR_SIZE_VER0 64 /* sizeof first published struct */ #define PERF_ATTR_SIZE_VER1 72 /* add: config2 */ #define PERF_ATTR_SIZE_VER2 80 /* add: branch_sample_type */ -#define PERF_ATTR_SIZE_VER3 88 /* add: sample_regs_user */ -#define PERF_ATTR_SIZE_VER4 96 /* add: sample_stack_user */ +#define PERF_ATTR_SIZE_VER3 96 /* add: sample_regs_user */ + /* add: sample_stack_user */ /* * Hardware event_id to monitor via a performance monitoring event: diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c index 63aad3109e34..9696e64c9dbd 100644 --- a/tools/perf/util/header.c +++ b/tools/perf/util/header.c @@ -2011,7 +2011,6 @@ static const int attr_file_abi_sizes[] = { [1] = PERF_ATTR_SIZE_VER1, [2] = PERF_ATTR_SIZE_VER2, [3] = PERF_ATTR_SIZE_VER3, - [4] = PERF_ATTR_SIZE_VER4, 0, }; -- cgit v1.2.3