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authorNamhyung Kim <namhyung@kernel.org>2014-10-06 04:46:00 +0400
committerArnaldo Carvalho de Melo <acme@redhat.com>2014-10-16 00:38:23 +0400
commit66f066d8994bd146304bab72fa09c1e644c4b3ff (patch)
tree9e958638fe69c2df70107aab7015be8bc36da4f3 /tools/perf/util/unwind-libunwind.c
parent0cdccac6fe4b1316f04f0dbfcc4efab51932014a (diff)
downloadlinux-66f066d8994bd146304bab72fa09c1e644c4b3ff.tar.xz
perf callchain: Create an address space per thread
The unw_addr_space_t in libunwind represents an address space to be used for stack unwinding. It doesn't need to be create/destory everytime to unwind callchain (as in get_entries) and can have a same lifetime as thread (unless exec called). So move the address space construction/destruction logic to the thread lifetime handling functions. This is a preparation to enable caching in the unwind library. Note that it saves unw_addr_space_t object using thread__set_priv(). It seems currently only used by perf trace and perf kvm stat commands which don't use callchain. Signed-off-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Jean Pihet <jean.pihet@linaro.org> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Arun Sharma <asharma@fb.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jean Pihet <jean.pihet@linaro.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung.kim@lge.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1412556363-26229-3-git-send-email-namhyung@kernel.org [ Fixup unwind-libunwind.c missing CALLCHAIN_DWARF definition, added missing __maybe_unused on unused parameters in stubs at util/unwind.h ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf/util/unwind-libunwind.c')
-rw-r--r--tools/perf/util/unwind-libunwind.c37
1 files changed, 32 insertions, 5 deletions
diff --git a/tools/perf/util/unwind-libunwind.c b/tools/perf/util/unwind-libunwind.c
index 92b56db52471..e060386165c5 100644
--- a/tools/perf/util/unwind-libunwind.c
+++ b/tools/perf/util/unwind-libunwind.c
@@ -24,6 +24,7 @@
#include <linux/list.h>
#include <libunwind.h>
#include <libunwind-ptrace.h>
+#include "callchain.h"
#include "thread.h"
#include "session.h"
#include "perf_regs.h"
@@ -525,12 +526,12 @@ static unw_accessors_t accessors = {
.get_proc_name = get_proc_name,
};
-static int get_entries(struct unwind_info *ui, unwind_entry_cb_t cb,
- void *arg, int max_stack)
+int unwind__prepare_access(struct thread *thread)
{
unw_addr_space_t addr_space;
- unw_cursor_t c;
- int ret;
+
+ if (callchain_param.record_mode != CALLCHAIN_DWARF)
+ return 0;
addr_space = unw_create_addr_space(&accessors, 0);
if (!addr_space) {
@@ -538,6 +539,33 @@ static int get_entries(struct unwind_info *ui, unwind_entry_cb_t cb,
return -ENOMEM;
}
+ thread__set_priv(thread, addr_space);
+
+ return 0;
+}
+
+void unwind__finish_access(struct thread *thread)
+{
+ unw_addr_space_t addr_space;
+
+ if (callchain_param.record_mode != CALLCHAIN_DWARF)
+ return;
+
+ addr_space = thread__priv(thread);
+ unw_destroy_addr_space(addr_space);
+}
+
+static int get_entries(struct unwind_info *ui, unwind_entry_cb_t cb,
+ void *arg, int max_stack)
+{
+ unw_addr_space_t addr_space;
+ unw_cursor_t c;
+ int ret;
+
+ addr_space = thread__priv(ui->thread);
+ if (addr_space == NULL)
+ return -1;
+
ret = unw_init_remote(&c, addr_space, ui);
if (ret)
display_error(ret);
@@ -549,7 +577,6 @@ static int get_entries(struct unwind_info *ui, unwind_entry_cb_t cb,
ret = ip ? entry(ip, ui->thread, ui->machine, cb, arg) : 0;
}
- unw_destroy_addr_space(addr_space);
return ret;
}