DSOs were held on a list for fast iteration and in an rbtree for fast
finds.
Switch to using a lazily sorted array where iteration is just iterating
through the array and binary searches are the same complexity as
searching the rbtree.
The find may need to sort the array first which does increase the
complexity, but add operations have lower complexity and overall the
complexity should remain about the same.
The set name operations on the dso just records that the array is no
longer sorted, avoiding complexity in rebalancing the rbtree.
Tighter locking discipline is enforced to avoid the array being resorted
while long and short names or ids are changed.
The array is smaller in size, replacing 6 pointers with 2, and so even
with extra allocated space in the array, the array may be 50%
unoccupied, the memory saving should be at least 2x.
Committer testing:
On a previous version of this patchset we were getting a lot of warnings
about deleting a DSO still on a list, now it is ok:
root@x1:~# perf probe -l
root@x1:~# perf probe finish_task_switch
Added new event:
probe:finish_task_switch (on finish_task_switch)
You can now use it in all perf tools, such as:
perf record -e probe:finish_task_switch -aR sleep 1
root@x1:~# perf probe -l
probe:finish_task_switch (on finish_task_switch@kernel/sched/core.c)
root@x1:~# perf trace -e probe:finish_task_switch/max-stack=8/ --max-events=1
0.000 migration/0/19 probe:finish_task_switch(__probe_ip: -1894408688)
finish_task_switch.isra.0 ([kernel.kallsyms])
__schedule ([kernel.kallsyms])
schedule ([kernel.kallsyms])
smpboot_thread_fn ([kernel.kallsyms])
kthread ([kernel.kallsyms])
ret_from_fork ([kernel.kallsyms])
ret_from_fork_asm ([kernel.kallsyms])
root@x1:~#
root@x1:~# perf probe -d probe:*
Removed event: probe:finish_task_switch
root@x1:~# perf probe -l
root@x1:~#
I also ran the full 'perf test' suite after applying this one, no
regressions.
Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Ben Gainey <ben.gainey@arm.com>
Cc: Changbin Du <changbin.du@huawei.com>
Cc: Chengen Du <chengen.du@canonical.com>
Cc: Colin Ian King <colin.i.king@gmail.com>
Cc: Dima Kogan <dima@secretsauce.net>
Cc: Ilkka Koskinen <ilkka@os.amperecomputing.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: K Prateek Nayak <kprateek.nayak@amd.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Leo Yan <leo.yan@linux.dev>
Cc: Li Dong <lidong@vivo.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paran Lee <p4ranlee@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <song@kernel.org>
Cc: Sun Haiyong <sunhaiyong@loongson.cn>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Tiezhu Yang <yangtiezhu@loongson.cn>
Cc: Yanteng Si <siyanteng@loongson.cn>
Cc: zhaimingbing <zhaimingbing@cmss.chinamobile.com>
Link: https://lore.kernel.org/r/20240504213803.218974-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Perf event names aren't case sensitive. For sysfs events the entire
directory of events is read then iterated comparing names in a case
insensitive way, most often to see if an event is present.
Consider:
$ perf stat -e inst_retired.any true
The event inst_retired.any may be present in any PMU, so every PMU's
sysfs events are loaded and then searched with strcasecmp to see if
any match. This event is only present on the cpu PMU as a JSON event
so a lot of events were loaded from sysfs unnecessarily just to prove
an event didn't exist there.
This change avoids loading all the events by assuming sysfs event
names are always either lower or uppercase. It uses file exists and
only loads the events when the desired event is present.
For the example above, the number of openat calls measured by 'perf
trace' on a tigerlake laptop goes from 325 down to 255. The reduction
will be larger for machines with many PMUs, particularly replicated
uncore PMUs.
Ensure pmu_aliases_parse() is called before all uses of the aliases
list, but remove some "pmu->sysfs_aliases_loaded" tests as they are now
part of the function.
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jing Zhang <renyu.zj@linux.alibaba.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Link: https://lore.kernel.org/r/20240502213507.2339733-7-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
I found that the debug build was a slowed down a lot by the maps lock
code since it checks the invariants whenever it gets the pointer to the
lock. This means it checks twice the invariants before and after the
access.
Instead, let's move the checking code within the lock area but after any
modification and remove it from the read paths. This would remove (more
than) half of the maps lock overhead.
The time for perf report with a huge data file (200k+ of MMAP2 events).
Non-debug Before After
--------- -------- --------
2m 43s 6m 45s 4m 21s
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240429225738.1491791-1-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
I sometimes see ("unknown type") in the result and it was because it
didn't check the type of stack variables properly during the instruction
tracking. The stack can carry constant values (without type info) and
if the target instruction is accessing the stack location, it resulted
in the "unknown type".
Maybe we could pick one of integer types for the constant, but it
doesn't really mean anything useful. Let's just drop the stack slot if
it doesn't have a valid type info.
Here's an example how it got the unknown type.
Note that 0xffffff48 = -0xb8.
-----------------------------------------------------------
find data type for 0xffffff48(reg6) at ...
CU for ...
frame base: cfa=0 fbreg=6
scope: [2/2] (die:11cb97f)
bb: [37 - 3a]
var [37] reg15 type='int' size=0x4 (die:0x1180633)
bb: [40 - 4b]
mov [40] imm=0x1 -> reg13
var [45] reg8 type='sigset_t*' size=0x8 (die:0x11a39ee)
mov [45] imm=0x1 -> reg2 <--- here reg2 has a constant
bb: [215 - 237]
mov [218] reg2 -> -0xb8(stack) constant <--- and save it to the stack
mov [225] reg13 -> -0xc4(stack) constant
call [22f] find_task_by_vgpid
call [22f] return -> reg0 type='struct task_struct*' size=0x8 (die:0x11881e8)
bb: [5c8 - 5cf]
bb: [2fb - 302]
mov [2fb] -0xc4(stack) -> reg13 constant
bb: [13b - 14d]
mov [143] 0xd50(reg3) -> reg5 type='struct task_struct*' size=0x8 (die:0xa31f3c)
bb: [153 - 153]
chk [153] reg6 offset=0xffffff48 ok=0 kind=0 fbreg <--- access here
found by insn track: 0xffffff48(reg6) type-offset=0
type='G<EF>^K<F6><AF>U' size=0 (die:0xffffffffffffffff)
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240502060011.1838090-7-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The following instruction pattern is used to access a global variable.
mov $0x231c0, %rax
movsql %edi, %rcx
mov -0x7dc94ae0(,%rcx,8), %rcx
cmpl $0x0, 0xa60(%rcx,%rax,1) <<<--- here
The first instruction set the address of the per-cpu variable (here, it
is 'runqueues' of type 'struct rq'). The second instruction seems like
a cpu number of the per-cpu base. The third instruction get the base
offset of per-cpu area for that cpu. The last instruction compares the
value of the per-cpu variable at the offset of 0xa60.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240502060011.1838090-5-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Like per-cpu base offset array, sometimes it accesses the global
variable directly using the offset. Allow this type of instructions as
long as it finds a global variable for the address.
movslq %edi, %rcx
mov -0x7dc94ae0(,%rcx,8), %rcx <<<--- here
As %rcx has a valid type (i.e. array index) from the first instruction,
it will be checked by the first case in check_matching_type(). But as
it's not a pointer type, the match will fail. But in this case, it
should check if it accesses the kernel global array variable.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240502060011.1838090-4-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull RISC-V fixes from Palmer Dabbelt:
- A fix for TASK_SIZE on rv64/NOMMU, to reflect the lack of user/kernel
separation
- A fix to avoid loading rv64/NOMMU kernel past the start of RAM
- A fix for RISCV_HWPROBE_EXT_ZVFHMIN on ilp32 to avoid signed integer
overflow in the bitmask
- The sud_test kselftest has been fixed to properly swizzle the syscall
number into the return register, which are not the same on RISC-V
- A fix for a build warning in the perf tools on rv32
- A fix for the CBO selftests, to avoid non-constants leaking into the
inline asm
- A pair of fixes for T-Head PBMT errata probing, which has been
renamed MAE by the vendor
* tag 'riscv-for-linus-6.9-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
RISC-V: selftests: cbo: Ensure asm operands match constraints, take 2
perf riscv: Fix the warning due to the incompatible type
riscv: T-Head: Test availability bit before enabling MAE errata
riscv: thead: Rename T-Head PBMT to MAE
selftests: sud_test: return correct emulated syscall value on RISC-V
riscv: hwprobe: fix invalid sign extension for RISCV_HWPROBE_EXT_ZVFHMIN
riscv: Fix loading 64-bit NOMMU kernels past the start of RAM
riscv: Fix TASK_SIZE on 64-bit NOMMU
We can't default to doing parallel tests as there are tests that compete
for the same resources and thus clash, for instance tests that put in
place 'perf probe' probes, that clean the probes without regard to other
tests needs, ARM64 coresight tests, Intel PT ones, etc.
So reintroduce --p/--parallel and make -S/--sequential the default.
We need to come up with infrastructure that state which tests can't run
in parallel because they need exclusive access to some resource,
something as simple as "probes" that would then avoid 'perf probe' tests
from running while other such test is running, or make the tests more
resilient, till then we can't use parallel mode as default.
While at it, document all these options in the 'perf test' man page.
Reported-by: Adrian Hunter <adrian.hunter@intel.com>
Reported-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Reported-by: James Clark <james.clark@arm.com>
Reviewed-by: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/lkml/Ziwm18BqIn_vc1vn@x1
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Memory sanitizer lacks an interceptor for scandirat, reporting all
memory it allocates as uninitialized. Memory sanitizer has a scandir
interceptor so use the fallback function in this case. This allows
'perf test' to run under memory sanitizer.
Additional notes from Ian on running in this mode:
Note, as msan needs to instrument memory allocations libraries need to
be compiled with it. I lacked the msan built libraries and so built
with:
```
$ make -C tools/perf O=/tmp/perf DEBUG=1 EXTRA_CFLAGS="-O0 -g
-fno-omit-frame-pointer -fsanitize=memory
-fsanitize-memory-track-origins" CC=clang CXX=clang++ HOSTCC=clang
NO_LIBTRACEEVENT=1 NO_LIBELF=1 BUILD_BPF_SKEL=0 NO_LIBPFM=1
```
oh, I disabled libbpf here as the bpf system call also lacks msan interceptors.
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240320163244.1287780-1-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
dso__disassemble_filename() tries to get the filename for objdump (or
capstone) using build-id. But I found sometimes it didn't disassemble
some functions.
It turned out that those functions belong to a DSO which has no binary
type set. It seems it sets the binary type for some special files only
- like kernel (kallsyms or kcore) or BPF images. And there's a logic to
skip dso with DSO_BINARY_TYPE__NOT_FOUND.
As it's checked the build-id cache link, it should set the binary type
as DSO_BINARY_TYPE__BUILD_ID_CACHE.
Fixes: 873a83731f ("perf annotate: Skip DSOs not found")
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240425005157.1104789-2-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Use a struct/bitmap rather than a copied string from lexer.
In lexer give improved error message when too many precise flags are
given or repeated modifiers.
Before:
$ perf stat -e 'cycles:kuk' true
event syntax error: 'cycles:kuk'
\___ Bad modifier
...
$ perf stat -e 'cycles:pppp' true
event syntax error: 'cycles:pppp'
\___ Bad modifier
...
$ perf stat -e '{instructions:p,cycles:pp}:pp' -a true
event syntax error: '..cycles:pp}:pp'
\___ Bad modifier
...
After:
$ perf stat -e 'cycles:kuk' true
event syntax error: 'cycles:kuk'
\___ Duplicate modifier 'k' (kernel)
...
$ perf stat -e 'cycles:pppp' true
event syntax error: 'cycles:pppp'
\___ Maximum precise value is 3
...
$ perf stat -e '{instructions:p,cycles:pp}:pp' true
event syntax error: '..cycles:pp}:pp'
\___ Maximum combined precise value is 3, adding precision to "cycles:pp"
...
Signed-off-by: Ian Rogers <irogers@google.com>
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Tested-by: Atish Patra <atishp@rivosinc.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Beeman Strong <beeman@rivosinc.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240416061533.921723-14-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Inline parse_events_evlist_error that is only used in
parse_events_error. Modify parse_events_error to not report a parser
error unless errors haven't already been reported. Make it clearer
that the latter case only happens for unrecognized input.
Before:
$ perf stat -e 'cycles/period=99999999999999999999/' true
event syntax error: 'cycles/period=99999999999999999999/'
\___ parser error
event syntax error: '..les/period=99999999999999999999/'
\___ Bad base 10 number "99999999999999999999"
Run 'perf list' for a list of valid events
Usage: perf stat [<options>] [<command>]
-e, --event <event> event selector. use 'perf list' to list available events
$ perf stat -e 'cycles:xyz' true
event syntax error: 'cycles:xyz'
\___ parser error
Run 'perf list' for a list of valid events
Usage: perf stat [<options>] [<command>]
-e, --event <event> event selector. use 'perf list' to list available events
After:
$ perf stat -e 'cycles/period=99999999999999999999/xyz' true
event syntax error: '..les/period=99999999999999999999/xyz'
\___ Bad base 10 number "99999999999999999999"
Run 'perf list' for a list of valid events
Usage: perf stat [<options>] [<command>]
-e, --event <event> event selector. use 'perf list' to list available events
$ perf stat -e 'cycles:xyz' true
event syntax error: 'cycles:xyz'
\___ Unrecognized input
Run 'perf list' for a list of valid events
Usage: perf stat [<options>] [<command>]
-e, --event <event> event selector. use 'perf list' to list available events
Signed-off-by: Ian Rogers <irogers@google.com>
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Tested-by: Atish Patra <atishp@rivosinc.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Beeman Strong <beeman@rivosinc.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240416061533.921723-13-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Use the error handler from the parse_state to give a more informative
error message.
Before:
$ perf stat -e 'cycles/period=99999999999999999999/' true
event syntax error: 'cycles/period=99999999999999999999/'
\___ parser error
Run 'perf list' for a list of valid events
Usage: perf stat [<options>] [<command>]
-e, --event <event> event selector. use 'perf list' to list available events
After:
$ perf stat -e 'cycles/period=99999999999999999999/' true
event syntax error: 'cycles/period=99999999999999999999/'
\___ parser error
event syntax error: '..les/period=99999999999999999999/'
\___ Bad base 10 number "99999999999999999999"
Run 'perf list' for a list of valid events
Usage: perf stat [<options>] [<command>]
-e, --event <event> event selector. use 'perf list' to list available events
Signed-off-by: Ian Rogers <irogers@google.com>
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Tested-by: Atish Patra <atishp@rivosinc.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Beeman Strong <beeman@rivosinc.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240416061533.921723-12-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
