From:   Adrian Hunter <adrian.hunter@intel.com>
To:     Arnaldo Carvalho de Melo <acme@kernel.org>
Cc:     Jiri Olsa <jolsa@redhat.com>, Namhyung Kim <namhyung@kernel.org>,
        Ian Rogers <irogers@google.com>, linux-kernel@vger.kernel.org,
        linux-perf-users@vger.kernel.org
Subject: [PATCH V2 4/9] perf symbols: Record whether a symbol is an alias for an IFUNC symbol
Date:   Tue, 31 Jan 2023 15:16:20 +0200
Message-Id: <20230131131625.6964-5-adrian.hunter@intel.com>
In-Reply-To: <20230131131625.6964-1-adrian.hunter@intel.com>
References: <20230131131625.6964-1-adrian.hunter@intel.com>
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Organization: Intel Finland Oy, Registered Address: PL 281, 00181 Helsinki, Business Identity Code: 0357606 - 4, Domiciled in Helsinki
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To assist with synthesizing plt symbols for IFUNCs, record whether a
symbol is an alias of an IFUNC symbol.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
---
 tools/perf/util/symbol.c | 4 ++++
 tools/perf/util/symbol.h | 2 ++
 2 files changed, 6 insertions(+)

diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index a024f06f75d8..d05727fcb30d 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -201,10 +201,14 @@ void symbols__fixup_duplicate(struct rb_root_cached *symbols)
 			continue;
 
 		if (choose_best_symbol(curr, next) == SYMBOL_A) {
+			if (next->type == STT_GNU_IFUNC)
+				curr->ifunc_alias = true;
 			rb_erase_cached(&next->rb_node, symbols);
 			symbol__delete(next);
 			goto again;
 		} else {
+			if (curr->type == STT_GNU_IFUNC)
+				next->ifunc_alias = true;
 			nd = rb_next(&curr->rb_node);
 			rb_erase_cached(&curr->rb_node, symbols);
 			symbol__delete(curr);
diff --git a/tools/perf/util/symbol.h b/tools/perf/util/symbol.h
index 2fdeb22bd02f..7558735543c2 100644
--- a/tools/perf/util/symbol.h
+++ b/tools/perf/util/symbol.h
@@ -64,6 +64,8 @@ struct symbol {
 	u8		inlined:1;
 	/** Has symbol__annotate2 been performed. */
 	u8		annotate2:1;
+	/** Symbol is an alias of an STT_GNU_IFUNC */
+	u8		ifunc_alias:1;
 	/** Architecture specific. Unused except on PPC where it holds st_other. */
 	u8		arch_sym;
 	/** The name of length namelen associated with the symbol. */
-- 
2.34.1