From 3741eb9f8c3be3ec59583881c1f49980dad844e0 Mon Sep 17 00:00:00 2001 From: Jacob Shin Date: Thu, 29 May 2014 17:26:51 +0200 Subject: [PATCH] perf tools: allow user to specify hardware breakpoint bp_len Currently bp_len is given a default value of 4. Allow user to override it: $ perf stat -e mem:0x1000/8 ^ bp_len If no value is given, it will default to 4 as it did before. Signed-off-by: Jacob Shin Signed-off-by: Suravee Suthikulpanit Acked-by: Jiri Olsa Reviewed-by: Oleg Nesterov Cc: Arnaldo Carvalho de Melo Cc: Ingo Molnar Cc: Namhyung Kim Cc: Peter Zijlstra Cc: xiakaixu Signed-off-by: Frederic Weisbecker --- tools/perf/Documentation/perf-record.txt | 7 +++++-- tools/perf/util/parse-events.c | 21 ++++++++++--------- tools/perf/util/parse-events.h | 2 +- tools/perf/util/parse-events.l | 1 + tools/perf/util/parse-events.y | 26 ++++++++++++++++++++++-- 5 files changed, 42 insertions(+), 15 deletions(-) diff --git a/tools/perf/Documentation/perf-record.txt b/tools/perf/Documentation/perf-record.txt index af9a54ece024..81a20f21a3e6 100644 --- a/tools/perf/Documentation/perf-record.txt +++ b/tools/perf/Documentation/perf-record.txt @@ -33,12 +33,15 @@ OPTIONS - a raw PMU event (eventsel+umask) in the form of rNNN where NNN is a hexadecimal event descriptor. - - a hardware breakpoint event in the form of '\mem:addr[:access]' + - a hardware breakpoint event in the form of '\mem:addr[/len][:access]' where addr is the address in memory you want to break in. Access is the memory access type (read, write, execute) it can - be passed as follows: '\mem:addr[:[r][w][x]]'. + be passed as follows: '\mem:addr[:[r][w][x]]'. len is the range, + number of bytes from specified addr, which the breakpoint will cover. If you want to profile read-write accesses in 0x1000, just set 'mem:0x1000:rw'. + If you want to profile write accesses in [0x1000~1008), just set + 'mem:0x1000/8:w'. --filter=:: Event filter. diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c index c659a3ca1283..efa1ff4cca63 100644 --- a/tools/perf/util/parse-events.c +++ b/tools/perf/util/parse-events.c @@ -526,7 +526,7 @@ do { \ } int parse_events_add_breakpoint(struct list_head *list, int *idx, - void *ptr, char *type) + void *ptr, char *type, u64 len) { struct perf_event_attr attr; @@ -536,14 +536,15 @@ int parse_events_add_breakpoint(struct list_head *list, int *idx, if (parse_breakpoint_type(type, &attr)) return -EINVAL; - /* - * We should find a nice way to override the access length - * Provide some defaults for now - */ - if (attr.bp_type == HW_BREAKPOINT_X) - attr.bp_len = sizeof(long); - else - attr.bp_len = HW_BREAKPOINT_LEN_4; + /* Provide some defaults if len is not specified */ + if (!len) { + if (attr.bp_type == HW_BREAKPOINT_X) + len = sizeof(long); + else + len = HW_BREAKPOINT_LEN_4; + } + + attr.bp_len = len; attr.type = PERF_TYPE_BREAKPOINT; attr.sample_period = 1; @@ -1364,7 +1365,7 @@ void print_events(const char *event_glob, bool name_only) printf("\n"); printf(" %-50s [%s]\n", - "mem:[:access]", + "mem:[/len][:access]", event_type_descriptors[PERF_TYPE_BREAKPOINT]); printf("\n"); } diff --git a/tools/perf/util/parse-events.h b/tools/perf/util/parse-events.h index db2cf78ff0f3..a19fbeb80943 100644 --- a/tools/perf/util/parse-events.h +++ b/tools/perf/util/parse-events.h @@ -104,7 +104,7 @@ int parse_events_add_numeric(struct list_head *list, int *idx, int parse_events_add_cache(struct list_head *list, int *idx, char *type, char *op_result1, char *op_result2); int parse_events_add_breakpoint(struct list_head *list, int *idx, - void *ptr, char *type); + void *ptr, char *type, u64 len); int parse_events_add_pmu(struct list_head *list, int *idx, char *pmu , struct list_head *head_config); enum perf_pmu_event_symbol_type diff --git a/tools/perf/util/parse-events.l b/tools/perf/util/parse-events.l index 906630bbf8eb..94eacb6c1ef7 100644 --- a/tools/perf/util/parse-events.l +++ b/tools/perf/util/parse-events.l @@ -159,6 +159,7 @@ branch_type { return term(yyscanner, PARSE_EVENTS__TERM_TYPE_BRANCH_SAMPLE_TYPE { {modifier_bp} { return str(yyscanner, PE_MODIFIER_BP); } : { return ':'; } +"/" { return '/'; } {num_dec} { return value(yyscanner, 10); } {num_hex} { return value(yyscanner, 16); } /* diff --git a/tools/perf/util/parse-events.y b/tools/perf/util/parse-events.y index 93c4c9fbc922..72def077dbbf 100644 --- a/tools/perf/util/parse-events.y +++ b/tools/perf/util/parse-events.y @@ -326,6 +326,28 @@ PE_NAME_CACHE_TYPE } event_legacy_mem: +PE_PREFIX_MEM PE_VALUE '/' PE_VALUE ':' PE_MODIFIER_BP sep_dc +{ + struct parse_events_evlist *data = _data; + struct list_head *list; + + ALLOC_LIST(list); + ABORT_ON(parse_events_add_breakpoint(list, &data->idx, + (void *) $2, $6, $4)); + $$ = list; +} +| +PE_PREFIX_MEM PE_VALUE '/' PE_VALUE sep_dc +{ + struct parse_events_evlist *data = _data; + struct list_head *list; + + ALLOC_LIST(list); + ABORT_ON(parse_events_add_breakpoint(list, &data->idx, + (void *) $2, NULL, $4)); + $$ = list; +} +| PE_PREFIX_MEM PE_VALUE ':' PE_MODIFIER_BP sep_dc { struct parse_events_evlist *data = _data; @@ -333,7 +355,7 @@ PE_PREFIX_MEM PE_VALUE ':' PE_MODIFIER_BP sep_dc ALLOC_LIST(list); ABORT_ON(parse_events_add_breakpoint(list, &data->idx, - (void *) $2, $4)); + (void *) $2, $4, 0)); $$ = list; } | @@ -344,7 +366,7 @@ PE_PREFIX_MEM PE_VALUE sep_dc ALLOC_LIST(list); ABORT_ON(parse_events_add_breakpoint(list, &data->idx, - (void *) $2, NULL)); + (void *) $2, NULL, 0)); $$ = list; } -- 2.20.1