perf jit: Add support for using TSC as a timestamp
Intel PT uses TSC as a timestamp, so add support for using TSC instead
of the monotonic clock. Use of TSC is selected by an environment
variable "JITDUMP_USE_ARCH_TIMESTAMP" and flagged in the jitdump file
with flag JITDUMP_FLAGS_ARCH_TIMESTAMP.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1457426330-30226-1-git-send-email-adrian.hunter@intel.com
[ Added the fixup from He Kuang to make it build on other arches, ]
[ such as aarch64, to avoid inserting this bisectiong breakage upstream ]
Link: http://lkml.kernel.org/r/1459482572-129494-1-git-send-email-hekuang@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/util/jitdump.c b/tools/perf/util/jitdump.c
index ad0c0bb..52fcef3 100644
--- a/tools/perf/util/jitdump.c
+++ b/tools/perf/util/jitdump.c
@@ -17,6 +17,7 @@
#include "strlist.h"
#include <elf.h>
+#include "tsc.h"
#include "session.h"
#include "jit.h"
#include "jitdump.h"
@@ -33,6 +34,7 @@
size_t bufsize;
FILE *in;
bool needs_bswap; /* handles cross-endianess */
+ bool use_arch_timestamp;
void *debug_data;
size_t nr_debug_entries;
uint32_t code_load_count;
@@ -158,13 +160,16 @@
header.flags = bswap_64(header.flags);
}
+ jd->use_arch_timestamp = header.flags & JITDUMP_FLAGS_ARCH_TIMESTAMP;
+
if (verbose > 2)
- pr_debug("version=%u\nhdr.size=%u\nts=0x%llx\npid=%d\nelf_mach=%d\n",
+ pr_debug("version=%u\nhdr.size=%u\nts=0x%llx\npid=%d\nelf_mach=%d\nuse_arch_timestamp=%d\n",
header.version,
header.total_size,
(unsigned long long)header.timestamp,
header.pid,
- header.elf_mach);
+ header.elf_mach,
+ jd->use_arch_timestamp);
if (header.flags & JITDUMP_FLAGS_RESERVED) {
pr_err("jitdump file contains invalid or unsupported flags 0x%llx\n",
@@ -172,10 +177,15 @@
goto error;
}
+ if (jd->use_arch_timestamp && !jd->session->time_conv.time_mult) {
+ pr_err("jitdump file uses arch timestamps but there is no timestamp conversion\n");
+ goto error;
+ }
+
/*
* validate event is using the correct clockid
*/
- if (jit_validate_events(jd->session)) {
+ if (!jd->use_arch_timestamp && jit_validate_events(jd->session)) {
pr_err("error, jitted code must be sampled with perf record -k 1\n");
goto error;
}
@@ -329,6 +339,23 @@
return 0;
}
+static uint64_t convert_timestamp(struct jit_buf_desc *jd, uint64_t timestamp)
+{
+ struct perf_tsc_conversion tc;
+
+ if (!jd->use_arch_timestamp)
+ return timestamp;
+
+ tc.time_shift = jd->session->time_conv.time_shift;
+ tc.time_mult = jd->session->time_conv.time_mult;
+ tc.time_zero = jd->session->time_conv.time_zero;
+
+ if (!tc.time_mult)
+ return 0;
+
+ return tsc_to_perf_time(timestamp, &tc);
+}
+
static int jit_repipe_code_load(struct jit_buf_desc *jd, union jr_entry *jr)
{
struct perf_sample sample;
@@ -410,7 +437,7 @@
id->tid = tid;
}
if (jd->sample_type & PERF_SAMPLE_TIME)
- id->time = jr->load.p.timestamp;
+ id->time = convert_timestamp(jd, jr->load.p.timestamp);
/*
* create pseudo sample to induce dso hit increment
@@ -499,7 +526,7 @@
id->tid = tid;
}
if (jd->sample_type & PERF_SAMPLE_TIME)
- id->time = jr->load.p.timestamp;
+ id->time = convert_timestamp(jd, jr->load.p.timestamp);
/*
* create pseudo sample to induce dso hit increment