From: Namhyung Kim <namhyung@kernel.org>
To: Arnaldo Carvalho de Melo <acme@kernel.org>,
Jiri Olsa <jolsa@kernel.org>,
Peter Zijlstra <peterz@infradead.org>
Cc: Ian Rogers <irogers@google.com>,
Adrian Hunter <adrian.hunter@intel.com>,
Ingo Molnar <mingo@kernel.org>,
LKML <linux-kernel@vger.kernel.org>,
linux-perf-users@vger.kernel.org,
Linus Torvalds <torvalds@linux-foundation.org>,
Stephane Eranian <eranian@google.com>,
Masami Hiramatsu <mhiramat@kernel.org>,
Andi Kleen <ak@linux.intel.com>,
linux-trace-devel@vger.kernel.org,
linux-toolchains@vger.kernel.org
Subject: [PATCH 32/52] perf dwarf-aux: Add die_find_variable_by_addr()
Date: Thu, 9 Nov 2023 15:59:51 -0800 [thread overview]
Message-ID: <20231110000012.3538610-33-namhyung@kernel.org> (raw)
In-Reply-To: <20231110000012.3538610-1-namhyung@kernel.org>
The die_find_variable_by_addr() is to find a variables in the given DIE
using given (PC-relative) address. Global variables will have a
location expression with DW_OP_addr which has an address so can simply
compare it with the address.
<1><143a7>: Abbrev Number: 2 (DW_TAG_variable)
<143a8> DW_AT_name : loops_per_jiffy
<143ac> DW_AT_type : <0x1cca>
<143b0> DW_AT_external : 1
<143b0> DW_AT_decl_file : 193
<143b1> DW_AT_decl_line : 213
<143b2> DW_AT_location : 9 byte block: 3 b0 46 41 82 ff ff ff ff
(DW_OP_addr: ffffffff824146b0)
Note that the type-offset should be calculated from the base address of
the global variable.
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
tools/perf/util/dwarf-aux.c | 79 +++++++++++++++++++++++++++++++++++++
tools/perf/util/dwarf-aux.h | 14 +++++++
2 files changed, 93 insertions(+)
diff --git a/tools/perf/util/dwarf-aux.c b/tools/perf/util/dwarf-aux.c
index 4bdcd3dea28f..7aa5fee0da19 100644
--- a/tools/perf/util/dwarf-aux.c
+++ b/tools/perf/util/dwarf-aux.c
@@ -1266,8 +1266,12 @@ int die_get_var_range(Dwarf_Die *sp_die, Dwarf_Die *vr_die, struct strbuf *buf)
struct find_var_data {
/* Target instruction address */
Dwarf_Addr pc;
+ /* Target memory address (for global data) */
+ Dwarf_Addr addr;
/* Target register */
unsigned reg;
+ /* Access offset, set for global data */
+ int offset;
};
/* Max number of registers DW_OP_regN supports */
@@ -1328,6 +1332,81 @@ Dwarf_Die *die_find_variable_by_reg(Dwarf_Die *sc_die, Dwarf_Addr pc, int reg,
};
return die_find_child(sc_die, __die_find_var_reg_cb, &data, die_mem);
}
+
+/* Only checks direct child DIEs in the given scope */
+static int __die_find_var_addr_cb(Dwarf_Die *die_mem, void *arg)
+{
+ struct find_var_data *data = arg;
+ int tag = dwarf_tag(die_mem);
+ ptrdiff_t off = 0;
+ Dwarf_Attribute attr;
+ Dwarf_Addr base, start, end;
+ Dwarf_Word size;
+ Dwarf_Die type_die;
+ Dwarf_Op *ops;
+ size_t nops;
+
+ if (tag != DW_TAG_variable)
+ return DIE_FIND_CB_SIBLING;
+
+ if (dwarf_attr(die_mem, DW_AT_location, &attr) == NULL)
+ return DIE_FIND_CB_SIBLING;
+
+ while ((off = dwarf_getlocations(&attr, off, &base, &start, &end, &ops, &nops)) > 0) {
+ if (ops->atom != DW_OP_addr)
+ continue;
+
+ if (data->addr < ops->number)
+ continue;
+
+ if (data->addr == ops->number) {
+ /* Update offset relative to the start of the variable */
+ data->offset = 0;
+ return DIE_FIND_CB_END;
+ }
+
+ if (die_get_real_type(die_mem, &type_die) == NULL)
+ continue;
+
+ if (dwarf_aggregate_size(&type_die, &size) < 0)
+ continue;
+
+ if (data->addr >= ops->number + size)
+ continue;
+
+ /* Update offset relative to the start of the variable */
+ data->offset = data->addr - ops->number;
+ return DIE_FIND_CB_END;
+ }
+ return DIE_FIND_CB_SIBLING;
+}
+
+/**
+ * die_find_variable_by_addr - Find variable located at given address
+ * @sc_die: a scope DIE
+ * @pc: the program address to find
+ * @addr: the data address to find
+ * @die_mem: a buffer to save the resulting DIE
+ * @offset: the offset in the resulting type
+ *
+ * Find the variable DIE located at the given address (in PC-relative mode).
+ * This is usually for global variables.
+ */
+Dwarf_Die *die_find_variable_by_addr(Dwarf_Die *sc_die, Dwarf_Addr pc,
+ Dwarf_Addr addr, Dwarf_Die *die_mem,
+ int *offset)
+{
+ struct find_var_data data = {
+ .pc = pc,
+ .addr = addr,
+ };
+ Dwarf_Die *result;
+
+ result = die_find_child(sc_die, __die_find_var_addr_cb, &data, die_mem);
+ if (result)
+ *offset = data.offset;
+ return result;
+}
#endif
/*
diff --git a/tools/perf/util/dwarf-aux.h b/tools/perf/util/dwarf-aux.h
index f9763d3b7572..4e64caac6df8 100644
--- a/tools/perf/util/dwarf-aux.h
+++ b/tools/perf/util/dwarf-aux.h
@@ -144,6 +144,11 @@ int die_get_var_range(Dwarf_Die *sp_die, Dwarf_Die *vr_die, struct strbuf *buf);
Dwarf_Die *die_find_variable_by_reg(Dwarf_Die *sc_die, Dwarf_Addr pc, int reg,
Dwarf_Die *die_mem);
+/* Find a (global) variable located in the 'addr' */
+Dwarf_Die *die_find_variable_by_addr(Dwarf_Die *sc_die, Dwarf_Addr pc,
+ Dwarf_Addr addr, Dwarf_Die *die_mem,
+ int *offset);
+
#else /* HAVE_DWARF_GETLOCATIONS_SUPPORT */
static inline int die_get_var_range(Dwarf_Die *sp_die __maybe_unused,
@@ -161,6 +166,15 @@ static inline Dwarf_Die *die_find_variable_by_reg(Dwarf_Die *sc_die __maybe_unus
return NULL;
}
+static inline Dwarf_Die *die_find_variable_by_addr(Dwarf_Die *sc_die __maybe_unused,
+ Dwarf_Addr pc __maybe_unused,
+ Dwarf_Addr addr __maybe_unused,
+ Dwarf_Die *die_mem __maybe_unused,
+ int *offset __maybe_unused)
+{
+ return NULL;
+}
+
#endif /* HAVE_DWARF_GETLOCATIONS_SUPPORT */
#endif /* _DWARF_AUX_H */
--
2.42.0.869.gea05f2083d-goog
next prev parent reply other threads:[~2023-11-10 0:03 UTC|newest]
Thread overview: 69+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-11-09 23:59 [RFC 00/52] perf tools: Introduce data type profiling (v2) Namhyung Kim
2023-11-09 23:59 ` [PATCH 01/52] perf annotate: Pass "-l" option to objdump conditionally Namhyung Kim
2023-11-09 23:59 ` [PATCH 02/52] perf annotate: Move raw_comment and raw_func_start Namhyung Kim
2023-11-09 23:59 ` [PATCH 03/52] perf tools: Add util/debuginfo.[ch] files Namhyung Kim
2023-11-09 23:59 ` [PATCH 04/52] perf dwarf-aux: Fix die_get_typename() for void * Namhyung Kim
2023-11-09 23:59 ` [PATCH 05/52] perf dwarf-aux: Move #ifdef code to the header file Namhyung Kim
2023-11-09 23:59 ` [PATCH 06/52] perf dwarf-aux: Add die_get_scopes() helper Namhyung Kim
2023-11-09 23:59 ` [PATCH 07/52] perf dwarf-aux: Add die_find_variable_by_reg() helper Namhyung Kim
2023-11-09 23:59 ` [PATCH 08/52] perf build: Add feature check for dwarf_getcfi() Namhyung Kim
2023-11-10 10:26 ` Masami Hiramatsu
2023-11-09 23:59 ` [PATCH 09/52] perf probe: Convert to check dwarf_getcfi feature Namhyung Kim
2023-11-10 10:25 ` Masami Hiramatsu
2023-11-09 23:59 ` [PATCH 10/52] perf dwarf-aux: Factor out die_get_typename_from_type() Namhyung Kim
2023-11-09 23:59 ` [PATCH 11/52] perf dwarf-regs: Add get_dwarf_regnum() Namhyung Kim
2023-11-09 23:59 ` [PATCH 12/52] perf annotate-data: Add find_data_type() Namhyung Kim
[not found] ` <CA+JHD90fkWNrQWO5DrHeV8mCmFyKKqJ8fV=KwztRi7TSw+8yDg@mail.gmail.com>
2023-11-20 20:43 ` Namhyung Kim
2023-11-09 23:59 ` [PATCH 13/52] perf annotate-data: Add dso->data_types tree Namhyung Kim
2023-12-21 20:10 ` Arnaldo Carvalho de Melo
2023-12-21 20:13 ` Arnaldo Carvalho de Melo
2023-12-21 20:32 ` Arnaldo Carvalho de Melo
2023-11-09 23:59 ` [PATCH 14/52] perf annotate: Factor out evsel__get_arch() Namhyung Kim
2023-12-23 14:14 ` Arnaldo Carvalho de Melo
2023-11-09 23:59 ` [PATCH 15/52] perf annotate: Check if operand has multiple regs Namhyung Kim
2023-11-09 23:59 ` [PATCH 16/52] perf annotate: Add annotate_get_insn_location() Namhyung Kim
2023-11-09 23:59 ` [PATCH 17/52] perf annotate: Implement hist_entry__get_data_type() Namhyung Kim
2023-11-09 23:59 ` [PATCH 18/52] perf report: Add 'type' sort key Namhyung Kim
2023-11-21 17:55 ` Arnaldo Carvalho de Melo
2023-11-22 18:49 ` Namhyung Kim
2023-11-22 19:54 ` Arnaldo Carvalho de Melo
2023-11-22 21:13 ` Namhyung Kim
2023-11-23 13:40 ` Arnaldo Carvalho de Melo
2023-11-09 23:59 ` [PATCH 19/52] perf report: Support data type profiling Namhyung Kim
2023-11-09 23:59 ` [PATCH 20/52] perf annotate-data: Add member field in the data type Namhyung Kim
2023-11-09 23:59 ` [PATCH 21/52] perf annotate-data: Update sample histogram for type Namhyung Kim
2023-11-09 23:59 ` [PATCH 22/52] perf report: Add 'typeoff' sort key Namhyung Kim
2023-11-09 23:59 ` [PATCH 23/52] perf report: Add 'symoff' " Namhyung Kim
2023-12-23 14:29 ` Arnaldo Carvalho de Melo
2023-11-09 23:59 ` [PATCH 24/52] perf annotate: Add --data-type option Namhyung Kim
2023-11-09 23:59 ` [PATCH 25/52] perf annotate: Support event group display Namhyung Kim
2023-11-09 23:59 ` [PATCH 26/52] perf annotate: Add --type-stat option for debugging Namhyung Kim
2023-11-09 23:59 ` [PATCH 27/52] perf annotate: Add --insn-stat " Namhyung Kim
2023-11-09 23:59 ` [PATCH 28/52] perf annotate-data: Parse 'lock' prefix from llvm-objdump Namhyung Kim
2023-11-09 23:59 ` [PATCH 29/52] perf annotate-data: Handle macro fusion on x86 Namhyung Kim
2023-11-09 23:59 ` [PATCH 30/52] perf annotate-data: Handle array style accesses Namhyung Kim
2023-11-09 23:59 ` [PATCH 31/52] perf annotate-data: Add stack operation pseudo type Namhyung Kim
2023-11-09 23:59 ` Namhyung Kim [this message]
2023-11-27 22:07 ` [PATCH 32/52] perf dwarf-aux: Add die_find_variable_by_addr() Arnaldo Carvalho de Melo
2023-11-09 23:59 ` [PATCH 33/52] perf annotate-data: Handle PC-relative addressing Namhyung Kim
2023-11-09 23:59 ` [PATCH 34/52] perf annotate-data: Support global variables Namhyung Kim
2023-11-09 23:59 ` [PATCH 35/52] perf dwarf-aux: Add die_get_cfa() Namhyung Kim
2023-11-09 23:59 ` [PATCH 36/52] perf annotate-data: Support stack variables Namhyung Kim
2023-11-09 23:59 ` [PATCH 37/52] perf dwarf-aux: Check allowed DWARF Ops Namhyung Kim
2023-11-09 23:59 ` [PATCH 38/52] perf dwarf-aux: Add die_collect_vars() Namhyung Kim
2023-11-09 23:59 ` [PATCH 39/52] perf dwarf-aux: Handle type transfer for memory access Namhyung Kim
2023-11-09 23:59 ` [PATCH 40/52] perf annotate-data: Introduce struct data_loc_info Namhyung Kim
2023-11-10 0:00 ` [PATCH 41/52] perf map: Add map__objdump_2rip() Namhyung Kim
2023-11-10 0:00 ` [PATCH 42/52] perf annotate: Add annotate_get_basic_blocks() Namhyung Kim
2023-11-10 0:00 ` [PATCH 43/52] perf annotate-data: Maintain variable type info Namhyung Kim
2023-11-10 0:00 ` [PATCH 44/52] perf annotate-data: Add update_insn_state() Namhyung Kim
2023-11-10 0:00 ` [PATCH 45/52] perf annotate-data: Handle global variable access Namhyung Kim
2023-11-10 0:00 ` [PATCH 46/52] perf annotate-data: Handle call instructions Namhyung Kim
2023-11-10 0:00 ` [PATCH 47/52] perf annotate-data: Implement instruction tracking Namhyung Kim
2023-11-10 0:00 ` [PATCH 48/52] perf annotate: Parse x86 segment register location Namhyung Kim
2023-11-10 0:00 ` [PATCH 49/52] perf annotate-data: Handle this-cpu variables in kernel Namhyung Kim
2023-11-10 0:00 ` [PATCH 50/52] perf annotate-data: Track instructions with a this-cpu variable Namhyung Kim
2023-11-10 0:00 ` [PATCH 51/52] perf annotate-data: Add stack canary type Namhyung Kim
2023-11-10 0:00 ` [PATCH 52/52] perf annotate-data: Add debug message Namhyung Kim
2023-11-10 12:05 ` [RFC 00/52] perf tools: Introduce data type profiling (v2) Arnaldo Carvalho de Melo
2023-11-11 2:27 ` Namhyung Kim
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20231110000012.3538610-33-namhyung@kernel.org \
--to=namhyung@kernel.org \
--cc=acme@kernel.org \
--cc=adrian.hunter@intel.com \
--cc=ak@linux.intel.com \
--cc=eranian@google.com \
--cc=irogers@google.com \
--cc=jolsa@kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-perf-users@vger.kernel.org \
--cc=linux-toolchains@vger.kernel.org \
--cc=linux-trace-devel@vger.kernel.org \
--cc=mhiramat@kernel.org \
--cc=mingo@kernel.org \
--cc=peterz@infradead.org \
--cc=torvalds@linux-foundation.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).