The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array
member[1][2], introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning in
case the flexible array does not occur last in the structure, which will
help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by this
change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
sizeof(flexible-array-member) triggers a warning because flexible array
members have incomplete type[1]. There are some instances of code in
which the sizeof operator is being incorrectly/erroneously applied to
zero-length arrays and the result is zero. Such instances may be hiding
some bugs. So, this work (flexible-array member conversions) will also
help to get completely rid of those sorts of issues.
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Gustavo A. R. Silva <gustavo@embeddedor.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20200515172926.GA31976@embeddedor
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The low level index of raw branch records for the most recent branch can
be recorded in a sample with PERF_SAMPLE_BRANCH_HW_INDEX
branch_sample_type. Extend struct branch_stack to support it.
However, if the PERF_SAMPLE_BRANCH_HW_INDEX is not applied, only nr and
entries[] will be output by kernel. The pointer of entries[] could be
wrong, since the output format is different with new struct
branch_stack. Add a variable no_hw_idx in struct perf_sample to
indicate whether the hw_idx is output. Add get_branch_entry() to return
corresponding pointer of entries[0].
To make dummy branch sample consistent as new branch sample, add hw_idx
in struct dummy_branch_stack for cs-etm and intel-pt.
Apply the new struct branch_stack for synthetic events as well.
Extend test case sample-parsing to support new struct branch_stack.
Committer notes:
Renamed get_branch_entries() to perf_sample__branch_entries() to have
proper namespacing and pave the way for this to be moved to libperf,
eventually.
Add 'static' to that inline as it is in a header.
Add 'hw_idx' to 'struct dummy_branch_stack' in cs-etm.c to fix the build
on arm64.
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Pavel Gerasimov <pavel.gerasimov@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vitaly Slobodskoy <vitaly.slobodskoy@intel.com>
Link: http://lore.kernel.org/lkml/20200228163011.19358-2-kan.liang@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add kernel AUX area sampling definitions, which brings perf_event.h into
line with the kernel version.
New sample type PERF_SAMPLE_AUX requests a sample of the AUX area
buffer. New perf_event_attr member 'aux_sample_size' specifies the
desired size of the sample.
Also add support for parsing samples containing AUX area data i.e.
PERF_SAMPLE_AUX.
Committer notes:
I squashed the first two patches in this series to avoid breaking
automatic bisection, i.e. after applying only the original first patch
in this series we would have:
# perf test -v parsing
26: Sample parsing :
--- start ---
test child forked, pid 17018
sample format has changed, some new PERF_SAMPLE_ bit was introduced - test needs updating
test child finished with -1
---- end ----
Sample parsing: FAILED!
#
With the two paches combined:
# perf test parsing
26: Sample parsing : Ok
#
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20191115124225.5247-3-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Move the PERF_RECORD_KSYMBOL event definition into libperf's event.h
header include.
In order to keep libperf simple, we switch 'u64/u32/u16/u8' types used
events to their generic '__u*' versions.
Perf added 'u*' types mainly to ease up printing __u64 values
as stated in the linux/types.h comment:
/*
* We define u64 as uint64_t for every architecture
* so that we can print it with "%"PRIx64 without getting warnings.
*
* typedef __u64 u64;
* typedef __s64 s64;
*/
Add and use new PRI_lu64 and PRI_lx64 macros for that. Use extra '_' to
ease up the reading and differentiate them from standard PRI*64 macros.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190825181752.722-11-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Move the PERF_RECORD_THROTTLE event definition into libperf's event.h
header include.
In order to keep libperf simple, we switch 'u64/u32/u16/u8' types used
events to their generic '__u*' versions.
Perf added 'u*' types mainly to ease up printing __u64 values as stated
in the linux/types.h comment:
/*
* We define u64 as uint64_t for every architecture
* so that we can print it with "%"PRIx64 without getting warnings.
*
* typedef __u64 u64;
* typedef __s64 s64;
*/
Add and use new PRI_lu64 and PRI_lx64 macros for that. Use extra '_' to
ease up the reading and differentiate them from standard PRI*64 macros.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190825181752.722-10-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Move the PERF_RECORD_READ event definition to libperf's event.h header
include.
In order to keep libperf simple, we switch 'u64/u32/u16/u8' types used
events to their generic '__u*' versions.
Perf added 'u*' types mainly to ease up printing __u64 values
as stated in the linux/types.h comment:
/*
* We define u64 as uint64_t for every architecture
* so that we can print it with "%"PRIx64 without getting warnings.
*
* typedef __u64 u64;
* typedef __s64 s64;
*/
Add and use new PRI_lu64 and PRI_lx64 macros for that. Use extra '_' to
ease up the reading and differentiate them from standard PRI*64 macros.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190825181752.722-9-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Move the PERF_RECORD_LOST_SAMPLES event definition into libperf's
event.h header include.
In order to keep libperf simple, we switch 'u64/u32/u16/u8' types used
events to their generic '__u*' versions.
Perf added 'u*' types mainly to ease up printing __u64 values
as stated in the linux/types.h comment:
/*
* We define u64 as uint64_t for every architecture
* so that we can print it with "%"PRIx64 without getting warnings.
*
* typedef __u64 u64;
* typedef __s64 s64;
*/
Add and use new PRI_lu64 and PRI_lx64 macros for that. Use extra '_' to
ease up the reading and differentiate them from standard PRI*64 macros.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190825181752.722-8-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Move the lost_event event definition to libperf's event.h header
include.
In order to keep libperf simple, we switch 'u64/u32/u16/u8' types used
events to their generic '__u*' versions.
Perf added 'u*' types mainly to ease up printing __u64 values as stated
in the linux/types.h comment:
/*
* We define u64 as uint64_t for every architecture
* so that we can print it with "%"PRIx64 without getting warnings.
*
* typedef __u64 u64;
* typedef __s64 s64;
*/
Add and use new PRI_lu64 and PRI_lx64 macros for that. Use extra '_' to
ease up the reading and differentiate them from standard PRI*64 macros.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190825181752.722-7-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Move the fork_event event definition into libperf's event.h header
include.
In order to keep libperf simple, we switch 'u64/u32/u16/u8' types used
events to their generic '__u*' versions.
Perf added 'u*' types mainly to ease up printing __u64 values
as stated in the linux/types.h comment:
/*
* We define u64 as uint64_t for every architecture
* so that we can print it with "%"PRIx64 without getting warnings.
*
* typedef __u64 u64;
* typedef __s64 s64;
*/
Add and use new PRI_lu64 and PRI_lx64 macros for that. Using extra '_'
to ease up the reading and differentiate them from standard PRI*64
macros.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190825181752.722-6-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Moving mmap2_event event definition into libperf's event.h header
include.
In order to keep libperf simple, we switch 'u64/u32/u16/u8' types used
events to their generic '__u*' versions.
Perf added 'u*' types mainly to ease up printing __u64 values
as stated in the linux/types.h comment:
/*
* We define u64 as uint64_t for every architecture
* so that we can print it with "%"PRIx64 without getting warnings.
*
* typedef __u64 u64;
* typedef __s64 s64;
*/
Adding and using new PRI_lu64 and PRI_lx64 macros to be used for
that. Using extra '_' to ease up the reading and differentiate
them from standard PRI*64 macros.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/n/tip-ufs9ityr5w2xqwtd5w3p6dm4@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
