Jean Pihet <jean.pihet@...> writes: > > Hi > > On 19 May 2014 16:08, Prankul Garg <prankul.iiitm@...> wrote: > > Jean Pihet <jean.pihet <at> ...> writes: > > > >> > >> Hello, > >> > >> Indeed there is a problem in the ARM code for tracepoints. > >> After a good discussion with the perf maintainers a solution has be > >> found, cf. http://www.spinics.net/lists/arm-kernel/msg332293.html. > >> > >> Can you check if this fixes the problem? It does on my side on 3.15- rc4. > > > > Hi Jean, > > > > yes, it solved the problem but partially, i am getting different outputs for > > x86 and ARM. > > > > On x86(3.10.28): > > > > ./perf record -e kmem:kmalloc cal > > [ perf record: Woken up 1 times to write data ] > > [ perf record: Captured and wrote 0.009 MB perf.data (~381 samples) ] > > > > ./perf report > > # Overhead Command Shared Object Symbol > > # ........ ....... ................. .......................... > > # > > 96.77% cal [kernel.kallsyms] [k] kmem_cache_alloc_trace > > 3.23% cal [kernel.kallsyms] [k] __kmalloc > > > > ./perf report -v > > 96.77% cal /lib/modules/3.10.28+/build/vmlinux 0xffffffff81166f6d > > v [k] kmem_cache_alloc_trace > > 3.23% cal /lib/modules/3.10.28+/build/vmlinux 0xffffffff81166b24 > > v [k] __kmalloc > > > > ./perf buildid-list > > aef9a24fcddff67cd67bcc1fd27dbeaf86d35487 [kernel.kallsyms] > > > > > > but on ARM(3.4.0): > > > > ./perf record -e kmem:kmalloc cal > > [ perf record: Woken up 1 times to write data ] > > [ perf record: Captured and wrote 0.004 MB perf.data (~192 samples) ] > > > > ./perf report > > # Overhead Command Shared Object Symbol > > # ........ ....... ................. .......................... > > # > > 100.00% cal [ks8851] [k] 0x01247890 > > > > ./perf report -v > > 100.00% cal /lib/modules/3.4.0/.../ks8851.ko 0x1247890 l [k] > > 0x01247890 > > > > ./perf buildid-list > > d0898c01486575dddafc6686240186bdb4b4430a /lib/modules/3.4.0/.../ks8851.ko > > > > > > that means on ARM, it is not getting the buildid for [kernel.kallsyms]. > > > > Are you getting the same output for ARM and x86 ?? > Yes. Here is the output I have: > > root <at> axp-linaro:/home/linaro/linaro/kernel# ./linux/tools/perf/perf report -v > build id event received for vmlinux: 6db809b8adab308f64037970799dc836f6b96422 > Looking at the vmlinux_path (6 entries long) > Using /proc/kallsyms for symbols > # To display the perf.data header info, please use --header/--header-only option > # > # Samples: 12 of event 'kmem:kmalloc' > # Event count (approx.): 12 > # > # Overhead Command Shared Object Sy > # ........ ............ ................. ................................... > # > 91.67% stress_bt_v7 [kernel.kallsyms] 0xc00f1548 k [k] kmem_cache_alloc_t > 8.33% stress_bt_v7 [kernel.kallsyms] 0xc00f1400 k [k] __kmalloc > > # > # (For a higher level overview, try: perf report --sort comm,dso) > # > > root <at> axp-linaro:/home/linaro/linaro/kernel/linux# ./tools/perf/perf > buildid-list > 6db809b8adab308f64037970799dc836f6b96422 vmlinux > root <at> axp-linaro:/home/linaro/linaro/kernel/linux# > > perf is looking for symbols in vmlinux (if present in the current dir > or specified in the command line) and if not found from kallsyms. So > if I run 'perf report' from the kernel root dir, the symbols are from > vmlinux; if I run it from elsewhere the symbols are from kallsyms.
Hi Jean, yes, I am getting your point regarding vmlinux or /proc/kallsyms. For cross checking it i also run command ./perf report -k /proc/kallsyms or ./perf report --vmlinux /path/to/vmlinux but it didn't work for me. when i debug the same and just print the statement, *__dsos__findnew: (function defined in "tools/perf/util/dso.c") which dsos it is finding. So during perf record # ./perf record -e kmem:kmalloc cal dsos__findnew: [kernel.kallsyms] dsos__findnew: [ks8851] dsos__findnew: [exfat_fs] # ./perf report dsos__findnew: [ks8851] (say list of dsos 'd1') # cmdline : /opt/perf/perf record -e kmem:mm_page_alloc cal # event : name = kmem:mm_page_alloc, type = 2, config = 0x69, config1 = 0x0, config2 = 0x0, excl_usr = 0, excl_kern = 0, excl_host = 0, excl_guest = 1, precise_ip = 0 # pmu mappings: cpu = 4, software = 1, tracepoint = 2, breakpoint = 5 # ======== # dsos__findnew: [kernel.kallsyms] dsos__findnew: [ks8851] ..and many more (say list of dsos 'd2') Now it matches the 'd1' and 'd2', and those dsos which matches,of those corresponding buildid is generated. # Overhead Command Shared Object Symbol # ........ ....... ................. .......................... # 100.00% cal [ks8851] [k] 0x01247890 > > Also your build is quite old, a lot of changes went into perf since 3.4. I have also tried the same on kernel 3.10.17 but having the same issue. Since i'm working for a specific product, it's not easy for me to move on 3.15. Is TRACEPOINT events working verified on 3.15 only before that, wasn't it working ?? > > Regards, > Jean > > > > > regards, > > Prankul Garg > > > >> > >> The patch is under review by the ARM experts and hopefully should be > >> merged soon. > >> > >> Regards, > >> Jean > >> > >> On 16 May 2014 09:34, Jean Pihet <jean.pihet <at> ...> wrote: _______________________________________________ linaro-dev mailing list linaro-dev@lists.linaro.org http://lists.linaro.org/mailman/listinfo/linaro-dev
