Fix machine object to drop the reference to the map object after it
inserted it into machine->kmaps.
refcnt debugger shows what happened:
----
==== [2] ====
Unreclaimed map: 0x346f750
Refcount +1 => 1 at
./perf(map__new2+0xb5) [0x4bdea5]
./perf() [0x4b8aaf]
./perf(modules__parse+0xfc) [0x4a9cbc]
./perf() [0x4b83c0]
./perf(machine__create_kernel_maps+0x148) [0x4bb208]
./perf(machine__new_host+0xfa) [0x4bb3fa]
./perf(init_probe_symbol_maps+0x93) [0x5062b3]
./perf() [0x455ffa]
./perf(cmd_probe+0x6c) [0x4566bc]
./perf() [0x47abc5]
./perf(main+0x610) [0x421f90]
/lib64/libc.so.6(__libc_start_main+0xf5) [0x7f5373899af5]
./perf() [0x4220a9]
Refcount +1 => 2 at
./perf(maps__insert+0x9a) [0x4bfd4a]
./perf() [0x4b8acb]
./perf(modules__parse+0xfc) [0x4a9cbc]
./perf() [0x4b83c0]
./perf(machine__create_kernel_maps+0x148) [0x4bb208]
./perf(machine__new_host+0xfa) [0x4bb3fa]
./perf(init_probe_symbol_maps+0x93) [0x5062b3]
./perf() [0x455ffa]
./perf(cmd_probe+0x6c) [0x4566bc]
./perf() [0x47abc5]
./perf(main+0x610) [0x421f90]
/lib64/libc.so.6(__libc_start_main+0xf5) [0x7f5373899af5]
./perf() [0x4220a9]
Refcount -1 => 1 at
./perf(map_groups__exit+0x94) [0x4bea54]
./perf(machine__delete+0x3d) [0x4b91ed]
./perf(exit_probe_symbol_maps+0x28) [0x506358]
./perf() [0x45628a]
./perf(cmd_probe+0x6c) [0x4566bc]
./perf() [0x47abc5]
./perf(main+0x610) [0x421f90]
/lib64/libc.so.6(__libc_start_main+0xf5) [0x7f5373899af5]
./perf() [0x4220a9]
----
This pattern clearly shows that the refcnt of the map is acquired twice
by map__new2 and maps__insert but released onlu once at
map_groups__exit, when we purge its maps rbtree.
Since maps__insert already reference counted the map, we have to drop
the constructor (map__new2) reference count right after inserting it.
These happened in machine__findnew_module_map, as below.
----
# eu-addr2line -e ./perf -f 0x4b8aaf
machine__findnew_module_map inlined at util/machine.c:1046
in machine__create_module
util/machine.c:582
# eu-addr2line -e ./perf -f 0x4b8acb
map_groups__insert inlined at util/machine.c:585
in machine__create_module
util/map.h:208
----
(note that both are at util/machine.c:58X which is
machine__findnew_module_map)
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20151118064020.30709.40499.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Since dwarf_cfi_addrframe returns malloc'd Dwarf_Frame object, it has to
be freed after it is used.
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20151118064011.30709.65674.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Sometimes error messages in breaks the pretty output of 'perf test'.
For example:
# mv /lib/modules/4.3.0-rc4+/build/vmlinux{,.bak}
# perf test LLVM BPF
35: Test LLVM searching and compiling :
35.1: Basic BPF llvm compiling test : Ok
35.2: Test kbuild searching : Ok
35.3: Compile source for BPF prologue generation test : Ok
37: Test BPF filter :
37.1: Test basic BPF filtering : Ok
37.2: Test BPF prologue generation :Failed to find the path for kernel: No such file or directory FAILED!
This patch mute test cases thoroughly by redirect their stdout and
stderr to /dev/null when verbose == 0. After applying this patch:
# ./perf test LLVM BPF
35: Test LLVM searching and compiling :
35.1: Basic BPF llvm compiling test : Ok
35.2: Test kbuild searching : Ok
35.3: Compile source for BPF prologue generation test : Ok
37: Test BPF filter :
37.1: Test basic BPF filtering : Ok
37.2: Test BPF prologue generation : FAILED!
# ./perf test -v LLVM BPF
35: Test LLVM searching and compiling :
35.1: Basic BPF llvm compiling test :
--- start ---
test child forked, pid 13183
Kernel build dir is set to /lib/modules/4.3.0-rc4+/build
set env: KBUILD_DIR=/lib/modules/4.3.0-rc4+/build
...
bpf: config 'func=null_lseek file->f_mode offset orig' is ok
Looking at the vmlinux_path (7 entries long)
Failed to find the path for kernel: No such file or directory
bpf_probe: failed to convert perf probe eventsFailed to add events selected by BPF
test child finished with -1
---- end ----
Test BPF filter subtest 1: FAILED!
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1447749170-175898-6-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This patch prints each sub-tests results for BPF testcases.
Before:
# ./perf test BPF
37: Test BPF filter : Ok
After:
# ./perf test BPF
37: Test BPF filter :
37.1: Test basic BPF filtering : Ok
37.2: Test BPF prologue generation : Ok
When a failure happens:
# cat ~/.perfconfig
[llvm]
clang-path = "/bin/false"
# ./perf test BPF
37: Test BPF filter :
37.1: Test basic BPF filtering : Skip
37.2: Test BPF prologue generation : Skip
Suggested-and-Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1447749170-175898-5-git-send-email-wangnan0@huawei.com
[ Fixed up not to use .func in an anonymous union ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Currently 'perf test llvm' and 'perf test BPF' have multiple sub-tests,
but the result is provided in only one line:
# perf test LLVM
35: Test LLVM searching and compiling : Ok
This patch introduces sub-tests support, allowing 'perf test' to report
result for each sub-tests:
# perf test LLVM
35: Test LLVM searching and compiling :
35.1: Basic BPF llvm compiling test : Ok
35.2: Test kbuild searching : Ok
35.3: Compile source for BPF prologue generation test : Ok
When a failure happens:
# cat ~/.perfconfig
[llvm]
clang-path = "/bin/false"
# perf test LLVM
35: Test LLVM searching and compiling :
35.1: Basic BPF llvm compiling test : FAILED!
35.2: Test kbuild searching : Skip
35.3: Compile source for BPF prologue generation test : Skip
And:
# rm ~/.perfconfig
# ./perf test LLVM
35: Test LLVM searching and compiling :
35.1: Basic BPF llvm compiling test : Skip
35.2: Test kbuild searching : Skip
35.3: Compile source for BPF prologue generation test : Skip
Skip by user:
# ./perf test -s 1,`seq -s , 3 42`
1: vmlinux symtab matches kallsyms : Skip (user override)
2: detect openat syscall event : Ok
...
35: Test LLVM searching and compiling : Skip (user override)
...
Suggested-and-Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1447749170-175898-4-git-send-email-wangnan0@huawei.com
[ Changed so that func is not on an anonymous union ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Some tests have sub-tests we want to run, so allow passing this.
Wang tried to avoid having to touch all tests, but then, having the
test.func in an anonymous union makes the build fail on older compilers,
like the one in RHEL6, where:
test a = {
.func = foo,
};
fails.
To fix it leave the func pointer in the main structure and pass the subtest
index to all tests, end result function is the same, but we have just one
function pointer, not two, with and without the subtest index as an argument.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-5genj0ficwdmelpoqlds0u4y@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This patch allows creating only one BPF program for different
'probe_trace_event'(tev) entries generated by one
'perf_probe_event'(pev) if their prologues are identical.
This is done by comparing the argument list of different tev instances,
and the maps type of prologue and tev using a mapping array. This patch
utilizes qsort to sort the tevs. After sorting, tevs with identical
argument lists will be grouped together.
Test result:
Sample BPF program:
#define SEC(NAME) __attribute__((section(NAME), used))
SEC("inlines=no;"
"func=SyS_dup? oldfd")
int func(void *ctx)
{
return 1;
}
It would probe at SyS_dup2 and SyS_dup3, obtaining oldfd as its
argument.
The following cmdline shows a BPF program being loaded into the kernel
by perf:
# perf record -e ./test_bpf_arg.c sleep 4 & sleep 1 && ls /proc/$!/fd/ -l | grep bpf-prog
Before this patch:
# perf record -e ./test_bpf_arg.c sleep 4 & sleep 1 && ls /proc/$!/fd/ -l | grep bpf-prog
[1] 24858
lrwx------ 1 root root 64 Nov 14 04:09 3 -> anon_inode:bpf-prog
lrwx------ 1 root root 64 Nov 14 04:09 4 -> anon_inode:bpf-prog
...
After this patch:
# perf record -e ./test_bpf_arg.c sleep 4 & sleep 1 && ls /proc/$!/fd/ -l | grep bpf-prog
[1] 25699
lrwx------ 1 root root 64 Nov 14 04:10 3 -> anon_inode:bpf-prog
...
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1447749170-175898-3-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Two bugs in 'perf test BPF' are found when testing BPF prologue without
vmlinux:
# mv /lib/modules/4.3.0-rc4+/build/vmlinux{,.bak}
# ./perf test BPF
37: Test BPF filter :Failed to find the path for kernel: No such file or directory
Ok
Test BPF should fail in this case.
After this patch:
# ./perf test BPF
37: Test BPF filter :Failed to find the path for kernel: No such file or directory
FAILED!
# mv /lib/modules/4.3.0-rc4+/build/vmlinux{.bak,}
# ./perf test BPF
37: Test BPF filter : Ok
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1447749170-175898-2-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This patch introduces a new BPF script to test the BPF prologue adding
routines. The new script probes at null_lseek, which is the function pointer
used when we try to lseek on '/dev/null'.
The null_lseek function is chosen because it is used by function pointers, so
we don't need to consider inlining and LTO.
By extracting file->f_mode, bpf-script-test-prologue.c should know whether the
file is writable or readonly. According to llseek_loop() and
bpf-script-test-prologue.c, one fourth of total lseeks should be collected.
Committer note:
Testing it:
# perf test -v BPF
<SNIP>
Kernel build dir is set to /lib/modules/4.3.0+/build
set env: KBUILD_DIR=/lib/modules/4.3.0+/build
unset env: KBUILD_OPTS
include option is set to -nostdinc -isystem /usr/lib/gcc/x86_64-redhat-linux/4.9.2/include -I/home/git/linux/arch/x86/include -Iarch/x86/include/generated/uapi -Iarch/x86/include/generated -I/home/git/linux/include -Iinclude -I/home/git/linux/arch/x86/include/uapi -Iarch/x86/include/generated/uapi -I/home/git/linux/include/uapi -Iinclude/generated/uapi -include /home/git/linux/include/linux/kconfig.h
set env: NR_CPUS=4
set env: LINUX_VERSION_CODE=0x40300
set env: CLANG_EXEC=/usr/libexec/icecc/bin/clang
set env: CLANG_OPTIONS=-xc
set env: KERNEL_INC_OPTIONS= -nostdinc -isystem /usr/lib/gcc/x86_64-redhat-linux/4.9.2/include -I/home/git/linux/arch/x86/include -Iarch/x86/include/generated/uapi -Iarch/x86/include/generated -I/home/git/linux/include -Iinclude -I/home/git/linux/arch/x86/include/uapi -Iarch/x86/include/generated/uapi -I/home/git/linux/include/uapi -Iinclude/generated/uapi -include /home/git/linux/include/linux/kconfig.h
set env: WORKING_DIR=/lib/modules/4.3.0+/build
set env: CLANG_SOURCE=-
llvm compiling command template: echo '/*
* bpf-script-test-prologue.c
* Test BPF prologue
*/
#ifndef LINUX_VERSION_CODE
# error Need LINUX_VERSION_CODE
# error Example: for 4.2 kernel, put 'clang-opt="-DLINUX_VERSION_CODE=0x40200" into llvm section of ~/.perfconfig'
#endif
#define SEC(NAME) __attribute__((section(NAME), used))
#include <uapi/linux/fs.h>
#define FMODE_READ 0x1
#define FMODE_WRITE 0x2
static void (*bpf_trace_printk)(const char *fmt, int fmt_size, ...) =
(void *) 6;
SEC("func=null_lseek file->f_mode offset orig")
int bpf_func__null_lseek(void *ctx, int err, unsigned long f_mode,
unsigned long offset, unsigned long orig)
{
if (err)
return 0;
if (f_mode & FMODE_WRITE)
return 0;
if (offset & 1)
return 0;
if (orig == SEEK_CUR)
return 0;
return 1;
}
char _license[] SEC("license") = "GPL";
int _version SEC("version") = LINUX_VERSION_CODE;
' | $CLANG_EXEC -D__KERNEL__ -D__NR_CPUS__=$NR_CPUS -DLINUX_VERSION_CODE=$LINUX_VERSION_CODE $CLANG_OPTIONS $KERNEL_INC_OPTIONS -Wno-unused-value -Wno-pointer-sign -working-directory $WORKING_DIR -c "$CLANG_SOURCE" -target bpf -O2 -o -
libbpf: loading object '[bpf_prologue_test]' from buffer
libbpf: section .strtab, size 135, link 0, flags 0, type=3
libbpf: section .text, size 0, link 0, flags 6, type=1
libbpf: section .data, size 0, link 0, flags 3, type=1
libbpf: section .bss, size 0, link 0, flags 3, type=8
libbpf: section func=null_lseek file->f_mode offset orig, size 112, link 0, flags 6, type=1
libbpf: found program func=null_lseek file->f_mode offset orig
libbpf: section license, size 4, link 0, flags 3, type=1
libbpf: license of [bpf_prologue_test] is GPL
libbpf: section version, size 4, link 0, flags 3, type=1
libbpf: kernel version of [bpf_prologue_test] is 40300
libbpf: section .symtab, size 168, link 1, flags 0, type=2
bpf: config program 'func=null_lseek file->f_mode offset orig'
symbol:null_lseek file:(null) line:0 offset:0 return:0 lazy:(null)
parsing arg: file->f_mode into file, f_mode(1)
parsing arg: offset into offset
parsing arg: orig into orig
bpf: config 'func=null_lseek file->f_mode offset orig' is ok
Looking at the vmlinux_path (7 entries long)
Using /lib/modules/4.3.0+/build/vmlinux for symbols
Open Debuginfo file: /lib/modules/4.3.0+/build/vmlinux
Try to find probe point from debuginfo.
Matched function: null_lseek
Probe point found: null_lseek+0
Searching 'file' variable in context.
Converting variable file into trace event.
converting f_mode in file
f_mode type is unsigned int.
Searching 'offset' variable in context.
Converting variable offset into trace event.
offset type is long long int.
Searching 'orig' variable in context.
Converting variable orig into trace event.
orig type is int.
Found 1 probe_trace_events.
Opening /sys/kernel/debug/tracing//kprobe_events write=1
Writing event: p:perf_bpf_probe/func _text+4840528 f_mode=+68(%di):u32 offset=%si:s64 orig=%dx:s32
libbpf: don't need create maps for [bpf_prologue_test]
prologue: pass validation
prologue: slow path
prologue: fetch arg 0, base reg is %di
prologue: arg 0: offset 68
prologue: fetch arg 1, base reg is %si
prologue: fetch arg 2, base reg is %dx
add bpf event perf_bpf_probe:func and attach bpf program 3
adding perf_bpf_probe:func
adding perf_bpf_probe:func to 0x51672c0
mmap size 1052672B
Opening /sys/kernel/debug/tracing//kprobe_events write=1
Opening /sys/kernel/debug/tracing//uprobe_events write=1
Parsing probe_events: p:perf_bpf_probe/func _text+4840528 f_mode=+68(%di):u32 offset=%si:s64 orig=%dx:s32
Group:perf_bpf_probe Event:func probe:p
Writing event: -:perf_bpf_probe/func
test child finished with 0
---- end ----
Test BPF filter: Ok
#
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1447675815-166222-13-git-send-email-wangnan0@huawei.com
[ Added tools/perf/tests/llvm-src-prologue.c to .gitignore ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This patch generates a prologue for each 'struct probe_trace_event' for
fetching arguments for BPF programs.
After bpf__probe(), iterate over each program to check whether prologues are
required. If none of the 'struct perf_probe_event' programs will attach to have
at least one argument, simply skip preprocessor hooking. For those who a
prologue is required, call bpf__gen_prologue() and paste the original
instruction after the prologue.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1447675815-166222-12-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This patch generates a prologue for a BPF program which fetches arguments for
it. With this patch, the program can have arguments as follow:
SEC("lock_page=__lock_page page->flags")
int lock_page(struct pt_regs *ctx, int err, unsigned long flags)
{
return 1;
}
This patch passes at most 3 arguments from r3, r4 and r5. r1 is still the ctx
pointer. r2 is used to indicate if dereferencing was done successfully.
This patch uses r6 to hold ctx (struct pt_regs) and r7 to hold stack pointer
for result. Result of each arguments first store on stack:
low address
BPF_REG_FP - 24 ARG3
BPF_REG_FP - 16 ARG2
BPF_REG_FP - 8 ARG1
BPF_REG_FP
high address
Then loaded into r3, r4 and r5.
The output prologue for offn(...off2(off1(reg)))) should be:
r6 <- r1 // save ctx into a callee saved register
r7 <- fp
r7 <- r7 - stack_offset // pointer to result slot
/* load r3 with the offset in pt_regs of 'reg' */
(r7) <- r3 // make slot valid
r3 <- r3 + off1 // prepare to read unsafe pointer
r2 <- 8
r1 <- r7 // result put onto stack
call probe_read // read unsafe pointer
jnei r0, 0, err // error checking
r3 <- (r7) // read result
r3 <- r3 + off2 // prepare to read unsafe pointer
r2 <- 8
r1 <- r7
call probe_read
jnei r0, 0, err
...
/* load r2, r3, r4 from stack */
goto success
err:
r2 <- 1
/* load r3, r4, r5 with 0 */
goto usercode
success:
r2 <- 0
usercode:
r1 <- r6 // restore ctx
// original user code
If all of arguments reside in register (dereferencing is not
required), gen_prologue_fastpath() will be used to create
fast prologue:
r3 <- (r1 + offset of reg1)
r4 <- (r1 + offset of reg2)
r5 <- (r1 + offset of reg3)
r2 <- 0
P.S.
eBPF calling convention is defined as:
* r0 - return value from in-kernel function, and exit value
for eBPF program
* r1 - r5 - arguments from eBPF program to in-kernel function
* r6 - r9 - callee saved registers that in-kernel function will
preserve
* r10 - read-only frame pointer to access stack
Committer note:
At least testing if it builds and loads:
# cat test_probe_arg.c
struct pt_regs;
__attribute__((section("lock_page=__lock_page page->flags"), used))
int func(struct pt_regs *ctx, int err, unsigned long flags)
{
return 1;
}
char _license[] __attribute__((section("license"), used)) = "GPL";
int _version __attribute__((section("version"), used)) = 0x40300;
# perf record -e ./test_probe_arg.c usleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.016 MB perf.data ]
# perf evlist
perf_bpf_probe:lock_page
#
Signed-off-by: He Kuang <hekuang@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1447675815-166222-11-git-send-email-wangnan0@huawei.com
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
By extending the syntax of BPF object section names, this patch allows users to
config probing options like what they can do in 'perf probe'.
The error message in 'perf probe' is also updated.
Test result:
For following BPF file test_probe_glob.c:
# cat test_probe_glob.c
__attribute__((section("inlines=no;func=SyS_dup?"), used))
int func(void *ctx)
{
return 1;
}
char _license[] __attribute__((section("license"), used)) = "GPL";
int _version __attribute__((section("version"), used)) = 0x40300;
#
# ./perf record -e ./test_probe_glob.c ls /
...
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.013 MB perf.data ]
# ./perf evlist
perf_bpf_probe:func_1
perf_bpf_probe:func
After changing "inlines=no" to "inlines=yes":
# ./perf record -e ./test_probe_glob.c ls /
...
[ perf record: Woken up 2 times to write data ]
[ perf record: Captured and wrote 0.013 MB perf.data ]
# ./perf evlist
perf_bpf_probe:func_3
perf_bpf_probe:func_2
perf_bpf_probe:func_1
perf_bpf_probe:func
Then test 'force':
Use following program:
# cat test_probe_force.c
__attribute__((section("func=sys_write"), used))
int funca(void *ctx)
{
return 1;
}
__attribute__((section("force=yes;func=sys_write"), used))
int funcb(void *ctx)
{
return 1;
}
char _license[] __attribute__((section("license"), used)) = "GPL";
int _version __attribute__((section("version"), used)) = 0x40300;
#
# perf record -e ./test_probe_force.c usleep 1
Error: event "func" already exists.
Hint: Remove existing event by 'perf probe -d'
or force duplicates by 'perf probe -f'
or set 'force=yes' in BPF source.
event syntax error: './test_probe_force.c'
\___ Probe point exist. Try 'perf probe -d "*"' and set 'force=yes'
(add -v to see detail)
...
Then replace 'force=no' to 'force=yes':
# vim test_probe_force.c
# perf record -e ./test_probe_force.c usleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.017 MB perf.data ]
# perf evlist
perf_bpf_probe:func_1
perf_bpf_probe:func
#
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1447675815-166222-7-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
By extending the syntax of BPF object section names, this patch allows
users to attach BPF programs to symbols in modules. For example:
SEC("module=i915;"
"parse_cmds=i915_parse_cmds")
int parse_cmds(void *ctx)
{
return 1;
}
The implementation is very simple: like what 'perf probe' does, for module,
fill 'uprobe' field in 'struct perf_probe_event'. Other parts will be done
automatically.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David Ahern <dsahern@gmail.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kaixu Xia <xiakaixu@huawei.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1447675815-166222-5-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This patch adds a new syntax to the BPF object section name to support
probing at uprobe event. Now we can use BPF program like this:
SEC(
"exec=/lib64/libc.so.6;"
"libcwrite=__write"
)
int libcwrite(void *ctx)
{
return 1;
}
Where, in section name of a program, before the main config string, we
can use 'key=value' style options. Now the only option key is "exec",
for uprobes.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1447675815-166222-4-git-send-email-wangnan0@huawei.com
[ Changed the separator from \n to ; ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
regs_query_register_offset() in dwarf-regs.c is required by BPF
prologue. This patch compiles it if CONFIG_BPF_PROLOGUE is on to avoid
build failure when CONFIG_BPF_PROLOGUE is on but CONFIG_DWARF is not
set.
Signed-off-by: He Kuang <hekuang@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: He Kuang <hekuang@huawei.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1447675815-166222-10-git-send-email-wangnan0@huawei.com
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
If both LIBBPF and DWARF are detected, it is possible to create prologue
for eBPF programs to help them access kernel data. HAVE_BPF_PROLOGUE and
CONFIG_BPF_PROLOGUE are added as flags for this feature.
PERF_HAVE_ARCH_REGS_QUERY_REGISTER_OFFSET is introduced in commit
63ab024a5b ("perf tools:
regs_query_register_offset() infrastructure"), which indicates that an
architecture supports converting name of a register to its offset in
'struct pt_regs'. Without this support, BPF_PROLOGUE should be turned
off.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1447675815-166222-9-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This patch is a preparation for BPF prologue support which allows
generating a series of BPF bytecode for fetching kernel data before
calling program code. With the newly introduced multiple instances
support, perf is able to create different prologues for different kprobe
points.
Before this patch, a bpf_program can be loaded into kernel only once,
and get the only resulting fd. What this patch does is to allow creating
and loading different variants of one bpf_program, then fetching their
fds.
Here we describe the basic idea in this patch. The detailed description
of the newly introduced APIs can be found in comments in the patch body.
The key of this patch is the new mechanism in bpf_program__load().
Instead of loading BPF program into kernel directly, it calls a
'pre-processor' to generate program instances which would be finally
loaded into the kernel based on the original code. To enable the
generation of multiple instances, libbpf passes an index to the
pre-processor so it know which instance is being loaded.
Pre-processor should be called from libbpf's user (perf) using
bpf_program__set_prep(). The number of instances and the relationship
between indices and the target instance should be clear when calling
bpf_program__set_prep().
To retrieve a fd for a specific instance of a program,
bpf_program__nth_fd() is introduced. It returns the resulting fd
according to index.
Signed-off-by: He Kuang <hekuang@huawei.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: He Kuang <hekuang@huawei.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1447675815-166222-8-git-send-email-wangnan0@huawei.com
Signed-off-by: Wang Nan <wangnan0@huawei.com>
[ Enclosed multi-line if/else blocks with {}, (*func_ptr)() -> func_ptr() ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Copying it to tools/lib/string.c, the counterpart to the kernel's
lib/string.c.
This is preparation for enhancing BPF program configuration, which will
allow config string like 'inlines=yes'.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Jonathan Cameron <jic23@cam.ac.uk>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1447675815-166222-6-git-send-email-wangnan0@huawei.com
[ Copied it to tools/lib/string.c instead, to make it usable by other tools/ ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
That will contain more string functions with counterparts, sometimes
verbatim copies, in the kernel.
Acked-by: Wang Nan <wangnan0@huawei.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/n/tip-rah6g97kn21vfgmlramorz6o@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Fix copy/paste error in selftests_install rule which was copy-pasted
from the clean rule but not properly changed.
Signed-off-by: Kevin Hilman <khilman@linaro.org>
Cc: Bamvor Jian Zhang <bamvor.zhangjian@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Jonathan Cameron <jic23@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Pali Rohar <pali.rohar@gmail.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Roberta Dobrescu <roberta.dobrescu@gmail.com>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: linaro-kernel@lists.linaro.org
Link: http://lkml.kernel.org/r/1447797261-1775-1-git-send-email-khilman@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
$ rpm -q glibc
glibc-2.12-1.166.el6_7.1.x86_64
<SNIP>
CC /tmp/build/perf/tests/llvm.o
cc1: warnings being treated as errors
tests/llvm.c: In function ‘test_llvm__fetch_bpf_obj’:
tests/llvm.c:53: error: declaration of ‘index’ shadows a global declaration
/usr/include/string.h:489: error: shadowed declaration is here
<SNIP>
CC /tmp/build/perf/tests/bpf.o
cc1: warnings being treated as errors
tests/bpf.c: In function ‘__test__bpf’:
tests/bpf.c:149: error: declaration of ‘index’ shadows a global declaration
/usr/include/string.h:489: error: shadowed declaration is here
<SNIP>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: pi3orama@163.com
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Zefan Li <lizefan@huawei.com>
Fixes: b31de018a6 ("perf test: Enhance the LLVM test: update basic BPF test program")
Fixes: ba1fae431e ("perf test: Add 'perf test BPF'")
Link: http://lkml.kernel.org/n/tip-akpo4r750oya2phxoh9e3447@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
- Do not change the key of an object in a rbtree, this time it was
the one for DSOs lookup by its long_name, and the noticed symptom was
with 'perf buildid-list --with-hits' (Adrian Hunter)
- 'perf inject' is a pipe, events it doesn't touch should be passed
on, PERF_RECORD_LOST wasn't, fix it (Adrian Hunter)
- Make 'perf buildid-list' request event ordering, as it needs to
first get the mmap events to be able to mark wich DSOs had hits
(Adrian Hunter)
- Fix memory leaks on failure in 'perf probe' (Masami Hiramatsu, Wang Nan)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Merge tag 'perf-urgent-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent
Pull perf/urgent fixes from Arnaldo Carvalho de Melo:
- Do not change the key of an object in a rbtree, this time it was
the one for DSOs lookup by its long_name, and the noticed symptom was
with 'perf buildid-list --with-hits' (Adrian Hunter)
- 'perf inject' is a pipe, events it doesn't touch should be passed
on, PERF_RECORD_LOST wasn't, fix it (Adrian Hunter)
- Make 'perf buildid-list' request event ordering, as it needs to
first get the mmap events to be able to mark wich DSOs had hits
(Adrian Hunter)
- Fix memory leaks on failure in 'perf probe' (Masami Hiramatsu, Wang Nan)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
When probing with a glob, errors in add_probe_trace_event() won't be
passed to debuginfo__find_trace_events() because it would be modified by
probe_point_search_cb(). It causes a segfault if perf fails to find an
argument for a probe point matched by the glob. For example:
# ./perf probe -v -n 'SyS_dup? oldfd'
probe-definition(0): SyS_dup? oldfd
symbol:SyS_dup? file:(null) line:0 offset:0 return:0 lazy:(null)
parsing arg: oldfd into oldfd
1 arguments
Looking at the vmlinux_path (7 entries long)
Using /lib/modules/4.3.0-rc4+/build/vmlinux for symbols
Open Debuginfo file: /lib/modules/4.3.0-rc4+/build/vmlinux
Try to find probe point from debuginfo.
Matched function: SyS_dup3
found inline addr: 0xffffffff812095c0
Probe point found: SyS_dup3+0
Searching 'oldfd' variable in context.
Converting variable oldfd into trace event.
oldfd type is long int.
found inline addr: 0xffffffff812096d4
Probe point found: SyS_dup2+36
Searching 'oldfd' variable in context.
Failed to find 'oldfd' in this function.
Matched function: SyS_dup3
Probe point found: SyS_dup3+0
Searching 'oldfd' variable in context.
Converting variable oldfd into trace event.
oldfd type is long int.
Matched function: SyS_dup2
Probe point found: SyS_dup2+0
Searching 'oldfd' variable in context.
Converting variable oldfd into trace event.
oldfd type is long int.
Found 4 probe_trace_events.
Opening /sys/kernel/debug/tracing//kprobe_events write=1
Writing event: p:probe/SyS_dup3 _text+2135488 oldfd=%di:s64
Segmentation fault (core dumped)
#
This patch ensures that add_probe_trace_event() doesn't touches
tf->ntevs and tf->tevs if those functions fail.
After the patch:
# perf probe 'SyS_dup? oldfd'
Failed to find 'oldfd' in this function.
Added new events:
probe:SyS_dup3 (on SyS_dup? with oldfd)
probe:SyS_dup3_1 (on SyS_dup? with oldfd)
probe:SyS_dup2 (on SyS_dup? with oldfd)
You can now use it in all perf tools, such as:
perf record -e probe:SyS_dup2 -aR sleep 1
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1447417761-156094-3-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Fix memory leaking on the debuginfo__find_trace_events() failure path
which frees an array of probe_trace_events but doesn't clears all the
allocated sub-structures and strings.
So, before doing zfree(tevs), clear all the array elements which may
have allocated resources.
Reported-by: Wang Nan <wangnan0@huawei.com>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1447417761-156094-2-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
'perf buildid-list' processes events to determine hits (i.e. with-hits
option). That may not work if events are not sorted in order. i.e. MMAP
events must be processed before the samples that depend on them so that
sample processing can 'hit' the DSO to which the MMAP refers.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/1447408112-1920-3-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Commit 4598a0a6d2 ("perf symbols: Improve DSO long names lookup speed
with rbtree") Added a tree to lookup dsos by long name. That tree gets
corrupted whenever a dso long name is changed because the tree is not
updated.
One effect of that is buildid-list does not work with the 'with-hits'
option because dso lookup fails and results in two structs for the same
dso. The first has the buildid but no hits, the second has hits but no
buildid. e.g.
Before:
$ tools/perf/perf record ls
arch certs CREDITS Documentation firmware include
ipc Kconfig lib Makefile net REPORTING-BUGS
scripts sound usr block COPYING crypto
drivers fs init Kbuild kernel MAINTAINERS
mm README samples security tools virt
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.012 MB perf.data (11 samples) ]
$ tools/perf/perf buildid-list
574da826c66538a8d9060d393a8866289bd06005 [kernel.kallsyms]
30c94dc66a1fe95180c3d68d2b89e576d5ae213c /lib/x86_64-linux-gnu/libc-2.19.so
$ tools/perf/perf buildid-list -H
574da826c66538a8d9060d393a8866289bd06005 [kernel.kallsyms]
0000000000000000000000000000000000000000 /lib/x86_64-linux-gnu/libc-2.19.so
After:
$ tools/perf/perf buildid-list -H
574da826c66538a8d9060d393a8866289bd06005 [kernel.kallsyms]
30c94dc66a1fe95180c3d68d2b89e576d5ae213c /lib/x86_64-linux-gnu/libc-2.19.so
The fix is to record the root of the tree on the dso so that
dso__set_long_name() can update the tree when the long name changes.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Douglas Hatch <doug.hatch@hp.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Scott J Norton <scott.norton@hp.com>
Cc: Waiman Long <Waiman.Long@hp.com>
Fixes: 4598a0a6d2 ("perf symbols: Improve DSO long names lookup speed with rbtree")
Link: http://lkml.kernel.org/r/1447408112-1920-2-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When the root user tries to read a file owned by some other user we get:
# ls -la perf.data
-rw-------. 1 acme acme 20032 Nov 12 15:50 perf.data
# perf report
File perf.data not owned by current user or root (use -f to override)
# perf report -f | grep -v ^# | head -2
30.96% ls [kernel.vmlinux] [k] do_set_pte
28.24% ls libc-2.20.so [.] intel_check_word
#
That wasn't happening when the symbol code tried to read a JIT map,
where the same check was done but no forcing was possible, fix it.
Reported-by: Brendan Gregg <brendan.d.gregg@gmail.com>
Tested-by: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://permalink.gmane.org/gmane.linux.kernel.perf.user/2380
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
So no need to have a 'dso' member in 'popup_action', remove it as no
code is using it, already.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-76a6s0007slug0op0wkl6o8b@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When pressing 'd' the expected action is to filter all entries by the
DSO in the current entry, but for that the action->map needs to be set,
and only action->dso was being set, fix it.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Fixes: 045b80dd03 ("perf hists browser: Use the map to determine if a DSO is being used as a kernel")
Link: http://lkml.kernel.org/n/tip-xqhfzgoblq49lk5h5u82atro@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Normally symbols are read from the DSO and adjusted, if need be, so that
the symbol start matches the file offset in the DSO file (we want the
file offset because that is what we know from MMAP events). That is done
by dso__load_sym() which inserts the symbols *after* adjusting them.
In the case of kcore, the symbols have been read from kallsyms and the
symbol start is the memory address. The symbols have to be adjusted to
match the kcore file offsets. dso__split_kallsyms_for_kcore() does that,
but now the adjustment is being done *after* the symbols have been
inserted. It appears dso__split_kallsyms_for_kcore() was assuming that
changing the symbol start would not change the order in the rbtree -
which is, of course, not guaranteed.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Tested-by: Wang Nan <wangnan0@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/563CB241.2090701@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
User visible:
- Add missing newlines to some pr_err() calls (Arnaldo Carvalho de Melo)
- Print full source file paths when using
'perf annotate --print-line --full-paths' (Michael Petlan)
- Fix 'perf probe -d' when just one out of uprobes and kprobes is
enabled (Wang Nan)
Developer stuff:
- Add compiler.h to list.h to fix 'make perf-tar-src-pkg' generated
tarballs, i.e. out of tree building (Arnaldo Carvalho de Melo)
- Add the llvm-src-base.c and llvm-src-kbuild.c files, generated by the
'perf test' LLVM entries, when running it in-tree, to .gitignore (Yunlong Song)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Merge tag 'perf-urgent-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent
Pull perf/urgent fixes from Arnaldo Carvalho de Melo:
- Add missing newlines to some pr_err() calls (Arnaldo Carvalho de Melo)
- Print full source file paths when using
'perf annotate --print-line --full-paths' (Michael Petlan)
- Fix 'perf probe -d' when just one out of uprobes and kprobes is
enabled (Wang Nan)
- Add compiler.h to list.h to fix 'make perf-tar-src-pkg' generated
tarballs, i.e. out of tree building (Arnaldo Carvalho de Melo)
- Add the llvm-src-base.c and llvm-src-kbuild.c files, generated by the
'perf test' LLVM entries, when running it in-tree, to .gitignore (Yunlong Song)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
list.h needs WRITE_ONCE() since 7f5f873c6a ("rculist: Use WRITE_ONCE()
when deleting from reader-visible list") add it before including the
kernel's list.h file.
This fixes builds of 'make perf-tar-src-pkg' perf tool tarball builds,
i.e. out of tree builds.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-e0rb8f7jwz0jn24ttyick9u6@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
On kernel with only one out of CONFIG_KPROBE_EVENTS and
CONFIG_UPROBE_EVENTS enabled, 'perf probe -d' causes a segfault because
perf_del_probe_events() calls probe_file__get_events() with a negative
fd.
This patch fixes it by adding parameter validation at the entry of
probe_file__get_events() and probe_file__get_rawlist(). Since they are
both non-static public functions (in .h file), parameter verifying is
required.
v1 -> v2: Verify fd at the head of probe_file__get_rawlist() instead of
checking at call site (suggested by Masami and Arnaldo at [1,2]).
[1] http://lkml.kernel.org/r/50399556C9727B4D88A595C8584AAB37526048E3@GSjpTKYDCembx32.service.hitachi.net
[2] http://lkml.kernel.org/r/20151105155830.GV13236@kernel.org
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1446803415-83382-1-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Before:
[acme@zoo linux]$ perf evlist
WARNING: The perf.data file's data size field is 0 which is unexpected.
Was the 'perf record' command properly terminated?
non matching sample_type[acme@zoo linux]$
After:
[acme@zoo linux]$ perf evlist
WARNING: The perf.data file's data size field is 0 which is unexpected.
Was the 'perf record' command properly terminated?
non matching sample_type
[acme@zoo linux]$
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-wscok3a2s7yrj8156oc2r6qe@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The --full-paths option did not show the full source file paths in the 'perf
annotate' tool, because the value of the option was not propagated into the
related functions.
With this patch the value of the --full-paths option is known to the function
that composes the srcline string, so it prints the full path when necessary.
Committer Note:
This affects annotate when the --print-line option is used:
# perf annotate -h 2>&1 | grep print-line
-l, --print-line print matching source lines (may be slow)
Looking just at the lines that should be affected by this change:
Before:
# perf annotate --print-line --full-paths --stdio fput | grep '\.[ch]:[0-9]\+'
94.44 atomic64_64.h:114
5.56 file_table.c:265
file_table.c:265 5.56 : ffffffff81219a00: callq ffffffff81769360 <__fentry__>
atomic64_64.h:114 94.44 : ffffffff81219a05: lock decq 0x38(%rdi)
After:
# perf annotate --print-line --full-paths --stdio fput | grep '\.[ch]:[0-9]\+'
94.44 /home/git/linux/arch/x86/include/asm/atomic64_64.h:114
5.56 /home/git/linux/fs/file_table.c:265
/home/git/linux/fs/file_table.c:265 5.56 : ffffffff81219a00: callq ffffffff81769360 <__fentry__>
/home/git/linux/arch/x86/include/asm/atomic64_64.h:114 94.44 : ffffffff81219a05: lock decq 0x38(%rdi)
#
Signed-off-by: Michael Petlan <mpetlan@redhat.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Link: http://permalink.gmane.org/gmane.linux.kernel.perf.user/2365
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo reported that tracepoint filters seem to misbehave (ie. not
apply) on inherited events.
The fix is obvious; filters are only set on the actual (parent)
event, use the normal pattern of using this parent event for filters.
This is safe because each child event has a reference to it.
Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20151102095051.GN17308@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The perf_lock_task_context() function disables preemption across its
RCU read-side critical section because that critical section acquires
a scheduler lock. If there was a preemption during that RCU read-side
critical section, the rcu_read_unlock() could attempt to acquire scheduler
locks, resulting in deadlock.
However, recent optimizations to expedited grace periods mean that IPI
handlers that execute during preemptible RCU read-side critical sections
can now cause the subsequent rcu_read_unlock() to acquire scheduler locks.
Disabling preemption does nothiing to prevent these IPI handlers from
executing, so these optimizations introduced a deadlock. In theory,
this deadlock could be avoided by pulling all wakeups and printk()s out
from rnp->lock critical sections, but in practice this would re-introduce
some RCU CPU stall warning bugs.
Given that acquiring scheduler locks entails disabling interrupts, these
deadlocks can be avoided by disabling interrupts (instead of disabling
preemption) across any RCU read-side critical that acquires scheduler
locks and holds them across the rcu_read_unlock(). This commit therefore
makes this change for perf_lock_task_context().
Reported-by: Dave Jones <davej@codemonkey.org.uk>
Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Stephane Eranian <eranian@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20151104134838.GR29027@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
- libbpf error reporting improvements, using a strerror interface to
more precisely tell the user about problems with the provided
scriptlet, be it in C or as a ready made object file (Wang Nan)
- Do not be case sensitive when searching for matching 'perf test'
entries (Arnaldo Carvalho de Melo)
- Inform the user about objdump failures in 'perf annotate' (Andi Kleen)
Infrastructure:
- Improve the LLVM 'perf test' entry, introduce a new ones for
BPF and kbuild tests to check the environment used by clang to
compile .c scriptlets (Wang Nan)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Merge tag 'perf-core-for-mingo-2' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent
Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:
Fixes:
- libbpf error reporting improvements, using a strerror interface to
more precisely tell the user about problems with the provided
scriptlet, be it in C or as a ready made object file (Wang Nan)
- Do not be case sensitive when searching for matching 'perf test'
entries (Arnaldo Carvalho de Melo)
- Inform the user about objdump failures in 'perf annotate' (Andi Kleen)
Infrastructure changes:
- Improve the LLVM 'perf test' entry, introduce a new ones for
BPF and kbuild tests to check the environment used by clang to
compile .c scriptlets (Wang Nan)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Before:
# perf test llvm
# perf test LLVM
35: Test LLVM searching and compiling : Ok
#
After
# perf test llvm
35: Test LLVM searching and compiling : Ok
#
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-c1u05npqbf6epse17ovfejoj@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This patch adds BPF testcase for testing BPF event filtering.
By utilizing the result of 'perf test LLVM', this patch compiles the
eBPF sample program then test its ability. The BPF script in 'perf test
LLVM' lets only 50% samples generated by epoll_pwait() to be captured.
This patch runs that system call for 111 times, so the result should
contain 56 samples.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1446817783-86722-8-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This patch adds a kbuild testcase to check whether kernel headers can be
correctly found.
For example:
# mv /lib/modules/4.3.0-rc5{,.bak}
# perf test LLVM
38: Test LLVM searching and compiling : Skip
# perf test -v LLVM
...
<stdin>:11:10: fatal error: 'uapi/linux/fs.h' file not found
#include <uapi/linux/fs.h>
^
1 error generated.
ERROR: unable to compile -
Hint: Check error message shown above.
Hint: You can also pre-compile it into .o using:
clang -target bpf -O2 -c -
with proper -I and -D options.
Failed to compile test case: 'Test kbuild searching'
test child finished with -2
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1446817783-86722-7-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This patch replaces the original toy BPF program with the previously
introduced bpf-script-example.c. Dynamically embeddeding it into
'llvm-src-base.c'.
The newly introduced BPF program attaches a BPF program to
'sys_epoll_pwait()'. perf itself never use that syscall, so further test
can verify their result with it. The program would generate 1 sample in
every 2 calls of epoll_pwait() system call.
Since the resulting BPF object is useful per se for further tests,
test_llvm__fetch_bpf_obj() is introduced for creating BPF objects from
source. The LLVM test was rewritten to use it.
Committer note:
Running it:
[root@zoo wb]# perf test -v LLVM
35: Test LLVM searching and compiling :
--- start ---
test child forked, pid 17740
Kernel build dir is set to /lib/modules/4.3.0-rc1+/build
set env: KBUILD_DIR=/lib/modules/4.3.0-rc1+/build
unset env: KBUILD_OPTS
include option is set to -nostdinc -isystem /usr/lib/gcc/x86_64-redhat-linux/4.9.2/include -I/home/git/linux/arch/x86/include -Iarch/x86/include/generated/uapi -Iarch/x86/include/generated -I/home/git/linux/include -Iinclude -I/home/git/linux/arch/x86/include/uapi -Iarch/x86/include/generated/uapi -I/home/git/linux/include/uapi -Iinclude/generated/uapi -include /home/git/linux/include/linux/kconfig.h
set env: NR_CPUS=4
set env: LINUX_VERSION_CODE=0x40300
set env: CLANG_EXEC=/usr/libexec/icecc/bin/clang
set env: CLANG_OPTIONS=-xc
set env: KERNEL_INC_OPTIONS= -nostdinc -isystem /usr/lib/gcc/x86_64-redhat-linux/4.9.2/include -I/home/git/linux/arch/x86/include -Iarch/x86/include/generated/uapi -Iarch/x86/include/generated -I/home/git/linux/include -Iinclude -I/home/git/linux/arch/x86/include/uapi -Iarch/x86/include/generated/uapi -I/home/git/linux/include/uapi -Iinclude/generated/uapi -include /home/git/linux/include/linux/kconfig.h
set env: WORKING_DIR=/lib/modules/4.3.0-rc1+/build
set env: CLANG_SOURCE=-
llvm compiling command template: echo '/*
* bpf-script-example.c
* Test basic LLVM building
*/
#ifndef LINUX_VERSION_CODE
# error Need LINUX_VERSION_CODE
# error Example: for 4.2 kernel, put 'clang-opt="-DLINUX_VERSION_CODE=0x40200" into llvm section of ~/.perfconfig'
#endif
#define BPF_ANY 0
#define BPF_MAP_TYPE_ARRAY 2
#define BPF_FUNC_map_lookup_elem 1
#define BPF_FUNC_map_update_elem 2
static void *(*bpf_map_lookup_elem)(void *map, void *key) =
(void *) BPF_FUNC_map_lookup_elem;
static void *(*bpf_map_update_elem)(void *map, void *key, void *value, int flags) =
(void *) BPF_FUNC_map_update_elem;
struct bpf_map_def {
unsigned int type;
unsigned int key_size;
unsigned int value_size;
unsigned int max_entries;
};
#define SEC(NAME) __attribute__((section(NAME), used))
struct bpf_map_def SEC("maps") flip_table = {
.type = BPF_MAP_TYPE_ARRAY,
.key_size = sizeof(int),
.value_size = sizeof(int),
.max_entries = 1,
};
SEC("func=sys_epoll_pwait")
int bpf_func__sys_epoll_pwait(void *ctx)
{
int ind =0;
int *flag = bpf_map_lookup_elem(&flip_table, &ind);
int new_flag;
if (!flag)
return 0;
/* flip flag and store back */
new_flag = !*flag;
bpf_map_update_elem(&flip_table, &ind, &new_flag, BPF_ANY);
return new_flag;
}
char _license[] SEC("license") = "GPL";
int _version SEC("version") = LINUX_VERSION_CODE;
' | $CLANG_EXEC -D__KERNEL__ -D__NR_CPUS__=$NR_CPUS -DLINUX_VERSION_CODE=$LINUX_VERSION_CODE $CLANG_OPTIONS $KERNEL_INC_OPTIONS -Wno-unused-value -Wno-pointer-sign -working-directory $WORKING_DIR -c "$CLANG_SOURCE" -target bpf -O2 -o -
test child finished with 0
---- end ----
Test LLVM searching and compiling: Ok
[root@zoo wb]#
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1446817783-86722-6-git-send-email-wangnan0@huawei.com
Signed-off-by: He Kuang <hekuang@huawei.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
A series of bpf loader related error codes were introduced to help error
reporting. Functions were improved to return these new error codes.
Functions which return pointers were adjusted to encode error codes into
return value using the ERR_PTR() interface.
bpf_loader_strerror() was improved to convert these error messages to
strings. It checks the error codes and calls libbpf_strerror() and
strerror_r() accordingly, so caller don't need to consider checking the
range of the error code.
In bpf__strerror_load(), print kernel version of running kernel and the
object's 'version' section to notify user how to fix his/her program.
v1 -> v2:
Use macro for error code.
Fetch error message based on array index, eliminate for-loop.
Print version strings.
Before:
# perf record -e ./test_kversion_nomatch_program.o sleep 1
event syntax error: './test_kversion_nomatch_program.o'
\___ Failed to load program: Validate your program and check 'license'/'version' sections in your object
SKIP
After:
# perf record -e ./test_kversion_nomatch_program.o ls
event syntax error: './test_kversion_nomatch_program.o'
\___ 'version' (4.4.0) doesn't match running kernel (4.3.0)
SKIP
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1446818289-87444-1-git-send-email-wangnan0@huawei.com
[ Add 'static inline' to bpf__strerror_prepare_load() when LIBBPF is disabled ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
There are 2 places in llvm-utils.c which find kernel version information
through uname. This patch extracts the uname related code into a
fetch_kernel_version() function and puts it into util.h so it can be
reused.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1446818135-87310-1-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
