3:28 p.m.
Hi,
Trying to use the trace extension on a mainline kernel doesn't work, and it
stems from some struct renaming that has happened upstream.
These two patches update the internal naming to match the upstream one, and
includes some backwards-compatibility checks to figure out which naming version
to use depending on what symbols are available.
This was briefly tested on on both v5.4 and 5.9-rc1 kernels using QEMU's
dump-guest-memory. The kernel starts tracing some sched & initicall stuff from
boot, and "trace show" behaves just fine on both of these.
Cheers,
Valentin
Valentin Schneider (2):
extensions/trace: Rename trace_buffer to array_buffer
extensions/trace: Rename ring_buffer to trace_buffer
extensions/trace.c | 101 ++++++++++++++++++++++++++++-----------------
1 file changed, 63 insertions(+), 38 deletions(-)
--
2.27.0
3:28 p.m.
New subject: [PATCH 1/2] extensions/trace: Rename trace_buffer to array_buffer
This renaming is present from Linux v5.6 upwards, and was introduced by
commit:
1c5eb4481e01 ("tracing: Rename trace_buffer to array_buffer")
Rename the internal references from trace_buffer to array_buffer. Backwards
compatibility with older kernels is provided by checking whether struct
trace_array has an array_buffer field - should that not be the case, the
old naming scheme is used instead.
Signed-off-by: Valentin Schneider <valentin.schneider(a)arm.com>
---
extensions/trace.c | 53 ++++++++++++++++++++++++++++++----------------
1 file changed, 35 insertions(+), 18 deletions(-)
diff --git a/extensions/trace.c b/extensions/trace.c
index c26b6c7..b4bbb98 100644
--- a/extensions/trace.c
+++ b/extensions/trace.c
@@ -31,9 +31,9 @@ static int per_cpu_buffer_sizes;
*/
static int encapsulated_current_trace;
/*
- * trace_buffer is supported
+ * array_buffer (trace_buffer pre v5.8) is supported
*/
-static int trace_buffer_available;
+static int array_buffer_available;
/*
* max_buffer is supported
*/
@@ -51,9 +51,9 @@ static int buffer_page_real_end_available;
#define koffset(struct, member) struct##_##member##_offset
static int koffset(trace_array, current_trace);
-static int koffset(trace_array, trace_buffer);
+static int koffset(trace_array, array_buffer);
static int koffset(trace_array, max_buffer);
-static int koffset(trace_buffer, buffer);
+static int koffset(array_buffer, buffer);
static int koffset(trace_array, buffer);
static int koffset(tracer, name);
@@ -117,7 +117,7 @@ static ulong max_tr_trace;
struct trace_instance {
char name[NAME_MAX + 1];
- ulong trace_buffer;
+ ulong array_buffer;
ulong max_buffer;
ulong ring_buffer;
unsigned pages;
@@ -174,8 +174,7 @@ static int write_and_check(int fd, void *data, size_t size)
static int init_offsets(void)
{
-#define init_offset(struct, member) do { \
- koffset(struct, member) = MEMBER_OFFSET(#struct, #member);\
+#define check_offset(struct, member) do { \
if (koffset(struct, member) < 0) { \
fprintf(fp, "failed to init the offset, struct:"\
#struct ", member:" #member); \
@@ -184,12 +183,29 @@ static int init_offsets(void)
} \
} while (0)
+#define init_offset(struct, member) do { \
+ koffset(struct, member) = MEMBER_OFFSET(#struct, #member); \
+ check_offset(struct, member); \
+ } while (0)
+
+#define init_offset_alternative(struct, member, alt_struct, alt_member) do { \
+ koffset(struct, member) = MEMBER_OFFSET(#alt_struct, #alt_member); \
+ check_offset(struct, member); \
+ } while (0)
+
if (encapsulated_current_trace)
init_offset(trace_array, current_trace);
- if (trace_buffer_available) {
- init_offset(trace_array, trace_buffer);
- init_offset(trace_buffer, buffer);
+ if (array_buffer_available) {
+ if (MEMBER_EXISTS("trace_array", "array_buffer")) {
+ init_offset(trace_array, array_buffer);
+ init_offset(array_buffer, buffer);
+ } else {
+ init_offset_alternative(trace_array, array_buffer,
+ trace_array, trace_buffer);
+ init_offset_alternative(array_buffer, buffer,
+ trace_buffer, buffer);
+ }
if (max_buffer_available)
init_offset(trace_array, max_buffer);
@@ -486,17 +502,17 @@ out_fail:
static int ftrace_init_trace(struct trace_instance *ti, ulong instance_addr)
{
- if (trace_buffer_available) {
- ti->trace_buffer = instance_addr +
- koffset(trace_array, trace_buffer);
- read_value(ti->ring_buffer, ti->trace_buffer,
- trace_buffer, buffer);
+ if (array_buffer_available) {
+ ti->array_buffer = instance_addr +
+ koffset(trace_array, array_buffer);
+ read_value(ti->ring_buffer, ti->array_buffer,
+ array_buffer, buffer);
if (max_buffer_available) {
ti->max_buffer = instance_addr +
koffset(trace_array, max_buffer);
read_value(ti->max_tr_ring_buffer, ti->max_buffer,
- trace_buffer, buffer);
+ array_buffer, buffer);
}
} else {
read_value(ti->ring_buffer, instance_addr, trace_array, buffer);
@@ -683,8 +699,9 @@ static int ftrace_init(void)
current_trace = sym_current_trace->value;
}
- if (MEMBER_EXISTS("trace_array", "trace_buffer")) {
- trace_buffer_available = 1;
+ if (MEMBER_EXISTS("trace_array", "array_buffer") ||
+ MEMBER_EXISTS("trace_array", "trace_buffer")) {
+ array_buffer_available = 1;
if (MEMBER_EXISTS("trace_array", "max_buffer"))
max_buffer_available = 1;
--
2.27.0
3:28 p.m.
New subject: [PATCH 2/2] extensions/trace: Rename ring_buffer to trace_buffer
This renaming is present from Linux v5.6 upwards, and was introduced by
commit:
13292494379f ("tracing: Make struct ring_buffer less ambiguous")
Rename the internal references from ring_buffer to trace_buffer. Backwards
compatibility with older kernels is provided by checking whether struct
trace_buffer has a buffer field of type struct ring buffer - should that
not be the case, the newer naming scheme is used instead.
Signed-off-by: Valentin Schneider <valentin.schneider(a)arm.com>
---
extensions/trace.c | 50 +++++++++++++++++++++++++++-------------------
1 file changed, 29 insertions(+), 21 deletions(-)
diff --git a/extensions/trace.c b/extensions/trace.c
index b4bbb98..e252efa 100644
--- a/extensions/trace.c
+++ b/extensions/trace.c
@@ -57,10 +57,10 @@ static int koffset(array_buffer, buffer);
static int koffset(trace_array, buffer);
static int koffset(tracer, name);
-static int koffset(ring_buffer, pages);
-static int koffset(ring_buffer, flags);
-static int koffset(ring_buffer, cpus);
-static int koffset(ring_buffer, buffers);
+static int koffset(trace_buffer, pages);
+static int koffset(trace_buffer, flags);
+static int koffset(trace_buffer, cpus);
+static int koffset(trace_buffer, buffers);
static int koffset(ring_buffer_per_cpu, cpu);
static int koffset(ring_buffer_per_cpu, pages);
@@ -119,7 +119,7 @@ struct trace_instance {
char name[NAME_MAX + 1];
ulong array_buffer;
ulong max_buffer;
- ulong ring_buffer;
+ ulong trace_buffer;
unsigned pages;
struct ring_buffer_per_cpu *buffers;
@@ -225,11 +225,19 @@ static int init_offsets(void)
else if (kernel_symbol_exists("ring_buffer_read"))
gdb_set_crash_scope(symbol_value("ring_buffer_read"),
"ring_buffer_read");
- if (!per_cpu_buffer_sizes)
- init_offset(ring_buffer, pages);
- init_offset(ring_buffer, flags);
- init_offset(ring_buffer, cpus);
- init_offset(ring_buffer, buffers);
+ if (STREQ(MEMBER_TYPE_NAME("trace_buffer", "buffer"),
"ring_buffer")) {
+ if (!per_cpu_buffer_sizes)
+ init_offset_alternative(trace_buffer, pages, ring_buffer, pages);
+ init_offset_alternative(trace_buffer, flags, ring_buffer, flags);
+ init_offset_alternative(trace_buffer, cpus, ring_buffer, cpus);
+ init_offset_alternative(trace_buffer, buffers, ring_buffer, buffers);
+ } else {
+ if (!per_cpu_buffer_sizes)
+ init_offset(trace_buffer, pages);
+ init_offset(trace_buffer, flags);
+ init_offset(trace_buffer, cpus);
+ init_offset(trace_buffer, buffers);
+ }
if (MEMBER_SIZE("ring_buffer_per_cpu", "pages") == sizeof(ulong)) {
lockless_ring_buffer = 1;
@@ -287,10 +295,10 @@ static void print_offsets(void)
print_offset(trace_array, buffer);
print_offset(tracer, name);
- print_offset(ring_buffer, pages);
- print_offset(ring_buffer, flags);
- print_offset(ring_buffer, cpus);
- print_offset(ring_buffer, buffers);
+ print_offset(trace_buffer, pages);
+ print_offset(trace_buffer, flags);
+ print_offset(trace_buffer, cpus);
+ print_offset(trace_buffer, buffers);
print_offset(ring_buffer_per_cpu, cpu);
print_offset(ring_buffer_per_cpu, pages);
@@ -445,12 +453,12 @@ static void ftrace_destroy_buffers(struct ring_buffer_per_cpu
*buffers)
}
static int ftrace_init_buffers(struct ring_buffer_per_cpu *buffers,
- ulong ring_buffer, unsigned pages)
+ ulong trace_buffer, unsigned pages)
{
int i;
ulong buffers_array;
- read_value(buffers_array, ring_buffer, ring_buffer, buffers);
+ read_value(buffers_array, trace_buffer, trace_buffer, buffers);
for (i = 0; i < nr_cpu_ids; i++) {
if (!readmem(buffers_array + sizeof(ulong) * i, KVADDR,
@@ -505,7 +513,7 @@ static int ftrace_init_trace(struct trace_instance *ti, ulong
instance_addr)
if (array_buffer_available) {
ti->array_buffer = instance_addr +
koffset(trace_array, array_buffer);
- read_value(ti->ring_buffer, ti->array_buffer,
+ read_value(ti->trace_buffer, ti->array_buffer,
array_buffer, buffer);
if (max_buffer_available) {
@@ -515,19 +523,19 @@ static int ftrace_init_trace(struct trace_instance *ti, ulong
instance_addr)
array_buffer, buffer);
}
} else {
- read_value(ti->ring_buffer, instance_addr, trace_array, buffer);
- read_value(ti->pages, ti->ring_buffer, ring_buffer, pages);
+ read_value(ti->trace_buffer, instance_addr, trace_array, buffer);
+ read_value(ti->pages, ti->trace_buffer, trace_buffer, pages);
read_value(ti->max_tr_ring_buffer, max_tr_trace, trace_array, buffer);
if (ti->max_tr_ring_buffer)
- read_value(ti->max_tr_pages, ti->max_tr_ring_buffer, ring_buffer, pages);
+ read_value(ti->max_tr_pages, ti->max_tr_ring_buffer, trace_buffer, pages);
}
ti->buffers = calloc(sizeof(*ti->buffers), nr_cpu_ids);
if (ti->buffers == NULL)
goto out_fail;
- if (ftrace_init_buffers(ti->buffers, ti->ring_buffer,
+ if (ftrace_init_buffers(ti->buffers, ti->trace_buffer,
ti->pages) < 0)
goto out_fail;
--
2.27.0
11:30 p.m.
New subject: [PATCH 0/2] extensions/trace: Sync up with v5.8 struct renaming
Hi Valentin,
Thanks for the patchset.
I've cc'd this to the maintainer of the trace extension.
Xu Huan, could you please review the patchset?
(Apparently, Xu could not respond in March 2019, though.. [1]
Does anyone in Fujitsu know who can maintain this?)
[1] https://www.redhat.com/archives/crash-utility/2019-March/msg00030.html
Thanks,
Kazu
-----Original Message-----
Hi,
Trying to use the trace extension on a mainline kernel doesn't work, and it
stems from some struct renaming that has happened upstream.
These two patches update the internal naming to match the upstream one, and
includes some backwards-compatibility checks to figure out which naming version
to use depending on what symbols are available.
This was briefly tested on on both v5.4 and 5.9-rc1 kernels using QEMU's
dump-guest-memory. The kernel starts tracing some sched & initicall stuff from
boot, and "trace show" behaves just fine on both of these.
Cheers,
Valentin
Valentin Schneider (2):
extensions/trace: Rename trace_buffer to array_buffer
extensions/trace: Rename ring_buffer to trace_buffer
extensions/trace.c | 101 ++++++++++++++++++++++++++++-----------------
1 file changed, 63 insertions(+), 38 deletions(-)
--
2.27.0
--
Crash-utility mailing list
Crash-utility(a)redhat.com
https://www.redhat.com/mailman/listinfo/crash-utility
1:17 a.m.
New subject: [PATCH 0/2] extensions/trace: Sync up with v5.8 struct renaming
Bhupesh, Lianbo,
I have certainly cc'd Xu Huan (not seen in the email sent by the list for
some reason though), but no response for two weeks. so let's review this.
Valentin, please wait for a while.
Thanks,
Kazu
-----Original Message-----
Hi Valentin,
Thanks for the patchset.
I've cc'd this to the maintainer of the trace extension.
Xu Huan, could you please review the patchset?
(Apparently, Xu could not respond in March 2019, though.. [1]
Does anyone in Fujitsu know who can maintain this?)
[1] https://www.redhat.com/archives/crash-utility/2019-March/msg00030.html
Thanks,
Kazu
-----Original Message-----
> Hi,
>
> Trying to use the trace extension on a mainline kernel doesn't work, and it
> stems from some struct renaming that has happened upstream.
>
> These two patches update the internal naming to match the upstream one, and
> includes some backwards-compatibility checks to figure out which naming version
> to use depending on what symbols are available.
>
> This was briefly tested on on both v5.4 and 5.9-rc1 kernels using QEMU's
> dump-guest-memory. The kernel starts tracing some sched & initicall stuff from
> boot, and "trace show" behaves just fine on both of these.
>
> Cheers,
> Valentin
>
> Valentin Schneider (2):
> extensions/trace: Rename trace_buffer to array_buffer
> extensions/trace: Rename ring_buffer to trace_buffer
>
> extensions/trace.c | 101 ++++++++++++++++++++++++++++-----------------
> 1 file changed, 63 insertions(+), 38 deletions(-)
>
> --
> 2.27.0
>
>
> --
> Crash-utility mailing list
> Crash-utility(a)redhat.com
> https://www.redhat.com/mailman/listinfo/crash-utility
--
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Crash-utility(a)redhat.com
https://www.redhat.com/mailman/listinfo/crash-utility
1:54 a.m.
New subject: [PATCH 0/2] extensions/trace: Sync up with v5.8 struct renaming
-----Original Message-----
Hi,
Trying to use the trace extension on a mainline kernel doesn't work, and it
stems from some struct renaming that has happened upstream.
These two patches update the internal naming to match the upstream one, and
includes some backwards-compatibility checks to figure out which naming version
to use depending on what symbols are available.
This was briefly tested on on both v5.4 and 5.9-rc1 kernels using QEMU's
dump-guest-memory. The kernel starts tracing some sched & initicall stuff from
boot, and "trace show" behaves just fine on both of these.
as far as I've tested, sometimes "trace show" and "trace dump -t"
write
less output than "trace-cmd extract" on 5.6 kernels, so there might be
other changes in kernel.
But anyway, the fixes for the renaming look nicely done.
Acked-by: Kazuhito Hagio <k-hagio-ab(a)nec.com>
Thanks,
Kazu
Cheers,
Valentin
Valentin Schneider (2):
extensions/trace: Rename trace_buffer to array_buffer
extensions/trace: Rename ring_buffer to trace_buffer
extensions/trace.c | 101 ++++++++++++++++++++++++++++-----------------
1 file changed, 63 insertions(+), 38 deletions(-)
--
2.27.0
--
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devel@lists.crash-utility.osci.io
5 comments
2 participants
participants (2)
-
HAGIO KAZUHITO(萩尾 一仁) -
Valentin Schneider