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linux/tools/lib/api/io.h

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tools api: Add a lightweight buffered reading api The synthesize benchmark shows the majority of execution time going to fgets and sscanf, necessary to parse /proc/pid/maps. Add a new buffered reading library that will be used to replace these calls in a follow-up CL. Add tests for the library to perf test. Committer tests: $ perf test api 63: Test api io : Ok $ Signed-off-by: Ian Rogers <irogers@google.com> Acked-by: Jiri Olsa <jolsa@redhat.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andrey Zhizhikin <andrey.z@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lore.kernel.org/lkml/20200415054050.31645-3-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-14 22:40:49 -07:00
tools api: Add io__getline Reads a line to allocated memory up to a newline following the getline API. Committer notes: It also adds this new function to the 'api io' 'perf test' entry: $ perf test "api io" 64: Test api io : Ok $ Signed-off-by: Ian Rogers <irogers@google.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Acked-by: Namhyung Kim <namhyung@kernel.org> 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: Nathan Chancellor <nathan@kernel.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Tom Rix <trix@redhat.com> Cc: llvm@lists.linux.dev Link: https://lore.kernel.org/r/20230403184033.1836023-2-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-04-03 11:40:30 -07:00
tools api: Add simple timeout to io read In situations like reading from a pipe it can be useful to have a timeout so that the caller doesn't block indefinitely. Implement a simple one based on poll. Signed-off-by: Ian Rogers <irogers@google.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.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> Cc: Yang Jihong <yangjihong1@huawei.com> Link: http://lore.kernel.org/lkml/20230608061812.3715566-1-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-06-07 23:18:11 -07:00
libsymbols kallsyms: Parse using io api 'perf record' will call kallsyms__parse 4 times during startup and process megabytes of data. This changes kallsyms__parse to use the io library rather than fgets to improve performance of the user code by over 8%. Before: Running 'internals/kallsyms-parse' benchmark: Average kallsyms__parse took: 103.988 ms (+- 0.203 ms) After: Running 'internals/kallsyms-parse' benchmark: Average kallsyms__parse took: 95.571 ms (+- 0.006 ms) For a workload like: $ perf record /bin/true Run under 'perf record -e cycles:u -g' the time goes from: Before 30.10% 1.67% perf perf [.] kallsyms__parse After 25.55% 20.04% perf perf [.] kallsyms__parse So a little under 5% of the start-up time is removed. A lot of what remains is on the kernel side, but caching kallsyms within perf would at least impact memory footprint. Committer notes: The internal/kallsyms-parse bench is run using: [root@five ~]# perf bench internals kallsyms-parse # Running 'internals/kallsyms-parse' benchmark: Average kallsyms__parse took: 80.381 ms (+- 0.115 ms) [root@five ~]# And this pre-existing test uses these routines to parse kallsyms and then compare with the info obtained from the matching ELF symtab: [root@five ~]# perf test vmlinux 1: vmlinux symtab matches kallsyms : Ok [root@five ~]# Also we can't remove hex2u64() in this patch as this breaks the build: /usr/bin/ld: /tmp/build/perf/perf-in.o: in function `modules__parse': /home/acme/git/perf/tools/perf/util/symbol.c:607: undefined reference to `hex2u64' /usr/bin/ld: /home/acme/git/perf/tools/perf/util/symbol.c:607: undefined reference to `hex2u64' /usr/bin/ld: /tmp/build/perf/perf-in.o: in function `dso__load_perf_map': /home/acme/git/perf/tools/perf/util/symbol.c:1477: undefined reference to `hex2u64' /usr/bin/ld: /home/acme/git/perf/tools/perf/util/symbol.c:1483: undefined reference to `hex2u64' collect2: error: ld returned 1 exit status Leave it there, move it in the next patch. Signed-off-by: Ian Rogers <irogers@google.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.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> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lore.kernel.org/lkml/20200501221315.54715-3-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-05-01 15:13:14 -07:00
tools api: Add io__getline Reads a line to allocated memory up to a newline following the getline API. Committer notes: It also adds this new function to the 'api io' 'perf test' entry: $ perf test "api io" 64: Test api io : Ok $ Signed-off-by: Ian Rogers <irogers@google.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Acked-by: Namhyung Kim <namhyung@kernel.org> 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: Nathan Chancellor <nathan@kernel.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Tom Rix <trix@redhat.com> Cc: llvm@lists.linux.dev Link: https://lore.kernel.org/r/20230403184033.1836023-2-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-04-03 11:40:30 -07:00
libsymbols kallsyms: Parse using io api 'perf record' will call kallsyms__parse 4 times during startup and process megabytes of data. This changes kallsyms__parse to use the io library rather than fgets to improve performance of the user code by over 8%. Before: Running 'internals/kallsyms-parse' benchmark: Average kallsyms__parse took: 103.988 ms (+- 0.203 ms) After: Running 'internals/kallsyms-parse' benchmark: Average kallsyms__parse took: 95.571 ms (+- 0.006 ms) For a workload like: $ perf record /bin/true Run under 'perf record -e cycles:u -g' the time goes from: Before 30.10% 1.67% perf perf [.] kallsyms__parse After 25.55% 20.04% perf perf [.] kallsyms__parse So a little under 5% of the start-up time is removed. A lot of what remains is on the kernel side, but caching kallsyms within perf would at least impact memory footprint. Committer notes: The internal/kallsyms-parse bench is run using: [root@five ~]# perf bench internals kallsyms-parse # Running 'internals/kallsyms-parse' benchmark: Average kallsyms__parse took: 80.381 ms (+- 0.115 ms) [root@five ~]# And this pre-existing test uses these routines to parse kallsyms and then compare with the info obtained from the matching ELF symtab: [root@five ~]# perf test vmlinux 1: vmlinux symtab matches kallsyms : Ok [root@five ~]# Also we can't remove hex2u64() in this patch as this breaks the build: /usr/bin/ld: /tmp/build/perf/perf-in.o: in function `modules__parse': /home/acme/git/perf/tools/perf/util/symbol.c:607: undefined reference to `hex2u64' /usr/bin/ld: /home/acme/git/perf/tools/perf/util/symbol.c:607: undefined reference to `hex2u64' /usr/bin/ld: /tmp/build/perf/perf-in.o: in function `dso__load_perf_map': /home/acme/git/perf/tools/perf/util/symbol.c:1477: undefined reference to `hex2u64' /usr/bin/ld: /home/acme/git/perf/tools/perf/util/symbol.c:1483: undefined reference to `hex2u64' collect2: error: ld returned 1 exit status Leave it there, move it in the next patch. Signed-off-by: Ian Rogers <irogers@google.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.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> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lore.kernel.org/lkml/20200501221315.54715-3-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-05-01 15:13:14 -07:00
libapi: Add missing linux/types.h header to get the __u64 type on io.h There are functions using __u64, so we need to have the linux/types.h header otherwise we'll break when its not included before api/io.h. Fixes: e95770af4c4a280f ("tools api: Add a lightweight buffered reading api") Reviewed-by: Ian Rogers <irogers@google.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Link: https://lore.kernel.org/lkml/ZWjDPL+IzPPsuC3X@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-11-30 14:11:45 -03:00
libsymbols kallsyms: Parse using io api 'perf record' will call kallsyms__parse 4 times during startup and process megabytes of data. This changes kallsyms__parse to use the io library rather than fgets to improve performance of the user code by over 8%. Before: Running 'internals/kallsyms-parse' benchmark: Average kallsyms__parse took: 103.988 ms (+- 0.203 ms) After: Running 'internals/kallsyms-parse' benchmark: Average kallsyms__parse took: 95.571 ms (+- 0.006 ms) For a workload like: $ perf record /bin/true Run under 'perf record -e cycles:u -g' the time goes from: Before 30.10% 1.67% perf perf [.] kallsyms__parse After 25.55% 20.04% perf perf [.] kallsyms__parse So a little under 5% of the start-up time is removed. A lot of what remains is on the kernel side, but caching kallsyms within perf would at least impact memory footprint. Committer notes: The internal/kallsyms-parse bench is run using: [root@five ~]# perf bench internals kallsyms-parse # Running 'internals/kallsyms-parse' benchmark: Average kallsyms__parse took: 80.381 ms (+- 0.115 ms) [root@five ~]# And this pre-existing test uses these routines to parse kallsyms and then compare with the info obtained from the matching ELF symtab: [root@five ~]# perf test vmlinux 1: vmlinux symtab matches kallsyms : Ok [root@five ~]# Also we can't remove hex2u64() in this patch as this breaks the build: /usr/bin/ld: /tmp/build/perf/perf-in.o: in function `modules__parse': /home/acme/git/perf/tools/perf/util/symbol.c:607: undefined reference to `hex2u64' /usr/bin/ld: /home/acme/git/perf/tools/perf/util/symbol.c:607: undefined reference to `hex2u64' /usr/bin/ld: /tmp/build/perf/perf-in.o: in function `dso__load_perf_map': /home/acme/git/perf/tools/perf/util/symbol.c:1477: undefined reference to `hex2u64' /usr/bin/ld: /home/acme/git/perf/tools/perf/util/symbol.c:1483: undefined reference to `hex2u64' collect2: error: ld returned 1 exit status Leave it there, move it in the next patch. Signed-off-by: Ian Rogers <irogers@google.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.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> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lore.kernel.org/lkml/20200501221315.54715-3-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-05-01 15:13:14 -07:00
tools api: Add a lightweight buffered reading api The synthesize benchmark shows the majority of execution time going to fgets and sscanf, necessary to parse /proc/pid/maps. Add a new buffered reading library that will be used to replace these calls in a follow-up CL. Add tests for the library to perf test. Committer tests: $ perf test api 63: Test api io : Ok $ Signed-off-by: Ian Rogers <irogers@google.com> Acked-by: Jiri Olsa <jolsa@redhat.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andrey Zhizhikin <andrey.z@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lore.kernel.org/lkml/20200415054050.31645-3-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-14 22:40:49 -07:00
tools api: Add simple timeout to io read In situations like reading from a pipe it can be useful to have a timeout so that the caller doesn't block indefinitely. Implement a simple one based on poll. Signed-off-by: Ian Rogers <irogers@google.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.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> Cc: Yang Jihong <yangjihong1@huawei.com> Link: http://lore.kernel.org/lkml/20230608061812.3715566-1-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-06-07 23:18:11 -07:00
tools api: Add a lightweight buffered reading api The synthesize benchmark shows the majority of execution time going to fgets and sscanf, necessary to parse /proc/pid/maps. Add a new buffered reading library that will be used to replace these calls in a follow-up CL. Add tests for the library to perf test. Committer tests: $ perf test api 63: Test api io : Ok $ Signed-off-by: Ian Rogers <irogers@google.com> Acked-by: Jiri Olsa <jolsa@redhat.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andrey Zhizhikin <andrey.z@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lore.kernel.org/lkml/20200415054050.31645-3-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-14 22:40:49 -07:00
tools api: Add simple timeout to io read In situations like reading from a pipe it can be useful to have a timeout so that the caller doesn't block indefinitely. Implement a simple one based on poll. Signed-off-by: Ian Rogers <irogers@google.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.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> Cc: Yang Jihong <yangjihong1@huawei.com> Link: http://lore.kernel.org/lkml/20230608061812.3715566-1-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-06-07 23:18:11 -07:00
tools api: Add a lightweight buffered reading api The synthesize benchmark shows the majority of execution time going to fgets and sscanf, necessary to parse /proc/pid/maps. Add a new buffered reading library that will be used to replace these calls in a follow-up CL. Add tests for the library to perf test. Committer tests: $ perf test api 63: Test api io : Ok $ Signed-off-by: Ian Rogers <irogers@google.com> Acked-by: Jiri Olsa <jolsa@redhat.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andrey Zhizhikin <andrey.z@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lore.kernel.org/lkml/20200415054050.31645-3-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-14 22:40:49 -07:00
tools api io: Move filling the io buffer to its own function In general a read fills 4kb so filling the buffer is a 1 in 4096 operation, move it out of the io__get_char function to avoid some checking overhead and to better hint the function is good to inline. For perf's IO intensive internal (non-rigorous) benchmarks there's a small improvement to kallsyms-parsing with a default build. Before: ``` $ perf bench internals all Computing performance of single threaded perf event synthesis by synthesizing events on the perf process itself: Average synthesis took: 146.322 usec (+- 0.305 usec) Average num. events: 61.000 (+- 0.000) Average time per event 2.399 usec Average data synthesis took: 145.056 usec (+- 0.155 usec) Average num. events: 329.000 (+- 0.000) Average time per event 0.441 usec Average kallsyms__parse took: 162.313 ms (+- 0.599 ms) ... Computing performance of sysfs PMU event scan for 100 times Average core PMU scanning took: 53.720 usec (+- 7.823 usec) Average PMU scanning took: 375.145 usec (+- 23.974 usec) ``` After: ``` $ perf bench internals all Computing performance of single threaded perf event synthesis by synthesizing events on the perf process itself: Average synthesis took: 127.829 usec (+- 0.079 usec) Average num. events: 61.000 (+- 0.000) Average time per event 2.096 usec Average data synthesis took: 133.652 usec (+- 0.101 usec) Average num. events: 327.000 (+- 0.000) Average time per event 0.409 usec Average kallsyms__parse took: 150.415 ms (+- 0.313 ms) ... Computing performance of sysfs PMU event scan for 100 times Average core PMU scanning took: 47.790 usec (+- 1.178 usec) Average PMU scanning took: 376.945 usec (+- 23.683 usec) ``` Signed-off-by: Ian Rogers <irogers@google.com> Signed-off-by: Namhyung Kim <namhyung@kernel.org> Link: https://lore.kernel.org/r/20240519181716.4088459-1-irogers@google.com
2024-05-19 11:17:16 -07:00
tools api: Add a lightweight buffered reading api The synthesize benchmark shows the majority of execution time going to fgets and sscanf, necessary to parse /proc/pid/maps. Add a new buffered reading library that will be used to replace these calls in a follow-up CL. Add tests for the library to perf test. Committer tests: $ perf test api 63: Test api io : Ok $ Signed-off-by: Ian Rogers <irogers@google.com> Acked-by: Jiri Olsa <jolsa@redhat.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andrey Zhizhikin <andrey.z@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lore.kernel.org/lkml/20200415054050.31645-3-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-14 22:40:49 -07:00
tools api io: Move filling the io buffer to its own function In general a read fills 4kb so filling the buffer is a 1 in 4096 operation, move it out of the io__get_char function to avoid some checking overhead and to better hint the function is good to inline. For perf's IO intensive internal (non-rigorous) benchmarks there's a small improvement to kallsyms-parsing with a default build. Before: ``` $ perf bench internals all Computing performance of single threaded perf event synthesis by synthesizing events on the perf process itself: Average synthesis took: 146.322 usec (+- 0.305 usec) Average num. events: 61.000 (+- 0.000) Average time per event 2.399 usec Average data synthesis took: 145.056 usec (+- 0.155 usec) Average num. events: 329.000 (+- 0.000) Average time per event 0.441 usec Average kallsyms__parse took: 162.313 ms (+- 0.599 ms) ... Computing performance of sysfs PMU event scan for 100 times Average core PMU scanning took: 53.720 usec (+- 7.823 usec) Average PMU scanning took: 375.145 usec (+- 23.974 usec) ``` After: ``` $ perf bench internals all Computing performance of single threaded perf event synthesis by synthesizing events on the perf process itself: Average synthesis took: 127.829 usec (+- 0.079 usec) Average num. events: 61.000 (+- 0.000) Average time per event 2.096 usec Average data synthesis took: 133.652 usec (+- 0.101 usec) Average num. events: 327.000 (+- 0.000) Average time per event 0.409 usec Average kallsyms__parse took: 150.415 ms (+- 0.313 ms) ... Computing performance of sysfs PMU event scan for 100 times Average core PMU scanning took: 47.790 usec (+- 1.178 usec) Average PMU scanning took: 376.945 usec (+- 23.683 usec) ``` Signed-off-by: Ian Rogers <irogers@google.com> Signed-off-by: Namhyung Kim <namhyung@kernel.org> Link: https://lore.kernel.org/r/20240519181716.4088459-1-irogers@google.com
2024-05-19 11:17:16 -07:00
tools api: Add a lightweight buffered reading api The synthesize benchmark shows the majority of execution time going to fgets and sscanf, necessary to parse /proc/pid/maps. Add a new buffered reading library that will be used to replace these calls in a follow-up CL. Add tests for the library to perf test. Committer tests: $ perf test api 63: Test api io : Ok $ Signed-off-by: Ian Rogers <irogers@google.com> Acked-by: Jiri Olsa <jolsa@redhat.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andrey Zhizhikin <andrey.z@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lore.kernel.org/lkml/20200415054050.31645-3-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-14 22:40:49 -07:00
tools api io: Move filling the io buffer to its own function In general a read fills 4kb so filling the buffer is a 1 in 4096 operation, move it out of the io__get_char function to avoid some checking overhead and to better hint the function is good to inline. For perf's IO intensive internal (non-rigorous) benchmarks there's a small improvement to kallsyms-parsing with a default build. Before: ``` $ perf bench internals all Computing performance of single threaded perf event synthesis by synthesizing events on the perf process itself: Average synthesis took: 146.322 usec (+- 0.305 usec) Average num. events: 61.000 (+- 0.000) Average time per event 2.399 usec Average data synthesis took: 145.056 usec (+- 0.155 usec) Average num. events: 329.000 (+- 0.000) Average time per event 0.441 usec Average kallsyms__parse took: 162.313 ms (+- 0.599 ms) ... Computing performance of sysfs PMU event scan for 100 times Average core PMU scanning took: 53.720 usec (+- 7.823 usec) Average PMU scanning took: 375.145 usec (+- 23.974 usec) ``` After: ``` $ perf bench internals all Computing performance of single threaded perf event synthesis by synthesizing events on the perf process itself: Average synthesis took: 127.829 usec (+- 0.079 usec) Average num. events: 61.000 (+- 0.000) Average time per event 2.096 usec Average data synthesis took: 133.652 usec (+- 0.101 usec) Average num. events: 327.000 (+- 0.000) Average time per event 0.409 usec Average kallsyms__parse took: 150.415 ms (+- 0.313 ms) ... Computing performance of sysfs PMU event scan for 100 times Average core PMU scanning took: 47.790 usec (+- 1.178 usec) Average PMU scanning took: 376.945 usec (+- 23.683 usec) ``` Signed-off-by: Ian Rogers <irogers@google.com> Signed-off-by: Namhyung Kim <namhyung@kernel.org> Link: https://lore.kernel.org/r/20240519181716.4088459-1-irogers@google.com
2024-05-19 11:17:16 -07:00
tools api: Add simple timeout to io read In situations like reading from a pipe it can be useful to have a timeout so that the caller doesn't block indefinitely. Implement a simple one based on poll. Signed-off-by: Ian Rogers <irogers@google.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.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> Cc: Yang Jihong <yangjihong1@huawei.com> Link: http://lore.kernel.org/lkml/20230608061812.3715566-1-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-06-07 23:18:11 -07:00
tools api io: Move filling the io buffer to its own function In general a read fills 4kb so filling the buffer is a 1 in 4096 operation, move it out of the io__get_char function to avoid some checking overhead and to better hint the function is good to inline. For perf's IO intensive internal (non-rigorous) benchmarks there's a small improvement to kallsyms-parsing with a default build. Before: ``` $ perf bench internals all Computing performance of single threaded perf event synthesis by synthesizing events on the perf process itself: Average synthesis took: 146.322 usec (+- 0.305 usec) Average num. events: 61.000 (+- 0.000) Average time per event 2.399 usec Average data synthesis took: 145.056 usec (+- 0.155 usec) Average num. events: 329.000 (+- 0.000) Average time per event 0.441 usec Average kallsyms__parse took: 162.313 ms (+- 0.599 ms) ... Computing performance of sysfs PMU event scan for 100 times Average core PMU scanning took: 53.720 usec (+- 7.823 usec) Average PMU scanning took: 375.145 usec (+- 23.974 usec) ``` After: ``` $ perf bench internals all Computing performance of single threaded perf event synthesis by synthesizing events on the perf process itself: Average synthesis took: 127.829 usec (+- 0.079 usec) Average num. events: 61.000 (+- 0.000) Average time per event 2.096 usec Average data synthesis took: 133.652 usec (+- 0.101 usec) Average num. events: 327.000 (+- 0.000) Average time per event 0.409 usec Average kallsyms__parse took: 150.415 ms (+- 0.313 ms) ... Computing performance of sysfs PMU event scan for 100 times Average core PMU scanning took: 47.790 usec (+- 1.178 usec) Average PMU scanning took: 376.945 usec (+- 23.683 usec) ``` Signed-off-by: Ian Rogers <irogers@google.com> Signed-off-by: Namhyung Kim <namhyung@kernel.org> Link: https://lore.kernel.org/r/20240519181716.4088459-1-irogers@google.com
2024-05-19 11:17:16 -07:00
tools api: Add simple timeout to io read In situations like reading from a pipe it can be useful to have a timeout so that the caller doesn't block indefinitely. Implement a simple one based on poll. Signed-off-by: Ian Rogers <irogers@google.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.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> Cc: Yang Jihong <yangjihong1@huawei.com> Link: http://lore.kernel.org/lkml/20230608061812.3715566-1-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-06-07 23:18:11 -07:00
tools api: Add a lightweight buffered reading api The synthesize benchmark shows the majority of execution time going to fgets and sscanf, necessary to parse /proc/pid/maps. Add a new buffered reading library that will be used to replace these calls in a follow-up CL. Add tests for the library to perf test. Committer tests: $ perf test api 63: Test api io : Ok $ Signed-off-by: Ian Rogers <irogers@google.com> Acked-by: Jiri Olsa <jolsa@redhat.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andrey Zhizhikin <andrey.z@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lore.kernel.org/lkml/20200415054050.31645-3-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-14 22:40:49 -07:00
tools api io: Move filling the io buffer to its own function In general a read fills 4kb so filling the buffer is a 1 in 4096 operation, move it out of the io__get_char function to avoid some checking overhead and to better hint the function is good to inline. For perf's IO intensive internal (non-rigorous) benchmarks there's a small improvement to kallsyms-parsing with a default build. Before: ``` $ perf bench internals all Computing performance of single threaded perf event synthesis by synthesizing events on the perf process itself: Average synthesis took: 146.322 usec (+- 0.305 usec) Average num. events: 61.000 (+- 0.000) Average time per event 2.399 usec Average data synthesis took: 145.056 usec (+- 0.155 usec) Average num. events: 329.000 (+- 0.000) Average time per event 0.441 usec Average kallsyms__parse took: 162.313 ms (+- 0.599 ms) ... Computing performance of sysfs PMU event scan for 100 times Average core PMU scanning took: 53.720 usec (+- 7.823 usec) Average PMU scanning took: 375.145 usec (+- 23.974 usec) ``` After: ``` $ perf bench internals all Computing performance of single threaded perf event synthesis by synthesizing events on the perf process itself: Average synthesis took: 127.829 usec (+- 0.079 usec) Average num. events: 61.000 (+- 0.000) Average time per event 2.096 usec Average data synthesis took: 133.652 usec (+- 0.101 usec) Average num. events: 327.000 (+- 0.000) Average time per event 0.409 usec Average kallsyms__parse took: 150.415 ms (+- 0.313 ms) ... Computing performance of sysfs PMU event scan for 100 times Average core PMU scanning took: 47.790 usec (+- 1.178 usec) Average PMU scanning took: 376.945 usec (+- 23.683 usec) ``` Signed-off-by: Ian Rogers <irogers@google.com> Signed-off-by: Namhyung Kim <namhyung@kernel.org> Link: https://lore.kernel.org/r/20240519181716.4088459-1-irogers@google.com
2024-05-19 11:17:16 -07:00
tools api: Add a lightweight buffered reading api The synthesize benchmark shows the majority of execution time going to fgets and sscanf, necessary to parse /proc/pid/maps. Add a new buffered reading library that will be used to replace these calls in a follow-up CL. Add tests for the library to perf test. Committer tests: $ perf test api 63: Test api io : Ok $ Signed-off-by: Ian Rogers <irogers@google.com> Acked-by: Jiri Olsa <jolsa@redhat.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andrey Zhizhikin <andrey.z@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lore.kernel.org/lkml/20200415054050.31645-3-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-14 22:40:49 -07:00
tools api fs: Switch filename__read_str to use io.h filename__read_str() has its own string reading code that allocates memory before reading into it. The memory allocated is sized at BUFSIZ that is 8kb. Most strings are short and so most of this 8kb is wasted. Refactor io__getline(), as io__getdelim(), so that the newline character can be configurable and ignored in the case of filename__read_str(). Code like build_caches_for_cpu() in perf's header.c will read many strings and hold them in a data structure, in this case multiple strings per cache level per CPU. Using io.h's io__getline() avoids the wasted memory as strings are temporarily read into a buffer on the stack before being copied to a buffer that grows 128 bytes at a time and is never sized larger than the string. For a 16 hyperthread system the memory consumption of "perf record true" is reduced by 180kb, primarily through saving memory when reading the cache information. Signed-off-by: Ian Rogers <irogers@google.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Athira Jajeev <atrajeev@linux.vnet.ibm.com> Cc: Changbin Du <changbin.du@huawei.com> Cc: Colin Ian King <colin.i.king@gmail.com> Cc: Dmitrii Dolgov <9erthalion6@gmail.com> Cc: German Gomez <german.gomez@arm.com> Cc: Guilherme Amadio <amadio@gentoo.org> Cc: Huacai Chen <chenhuacai@kernel.org> 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: Kajol Jain <kjain@linux.ibm.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Leo Yan <leo.yan@linaro.org> Cc: Li Dong <lidong@vivo.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Masami Hiramatsu (Google) <mhiramat@kernel.org> Cc: Miguel Ojeda <ojeda@kernel.org> Cc: Ming Wang <wangming01@loongson.cn> Cc: Nick Terrell <terrelln@fb.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi Bangoria <ravi.bangoria@amd.com> Cc: Sandipan Das <sandipan.das@amd.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Steinar H. Gunderson <sesse@google.com> Cc: Vincent Whitchurch <vincent.whitchurch@axis.com> Cc: Wenyu Liu <liuwenyu7@huawei.com> Cc: Yang Jihong <yangjihong1@huawei.com> Link: https://lore.kernel.org/r/20231127220902.1315692-5-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-11-27 14:08:16 -08:00
tools api: Add io__getline Reads a line to allocated memory up to a newline following the getline API. Committer notes: It also adds this new function to the 'api io' 'perf test' entry: $ perf test "api io" 64: Test api io : Ok $ Signed-off-by: Ian Rogers <irogers@google.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Acked-by: Namhyung Kim <namhyung@kernel.org> 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: Nathan Chancellor <nathan@kernel.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Tom Rix <trix@redhat.com> Cc: llvm@lists.linux.dev Link: https://lore.kernel.org/r/20230403184033.1836023-2-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-04-03 11:40:30 -07:00
tools api fs: Switch filename__read_str to use io.h filename__read_str() has its own string reading code that allocates memory before reading into it. The memory allocated is sized at BUFSIZ that is 8kb. Most strings are short and so most of this 8kb is wasted. Refactor io__getline(), as io__getdelim(), so that the newline character can be configurable and ignored in the case of filename__read_str(). Code like build_caches_for_cpu() in perf's header.c will read many strings and hold them in a data structure, in this case multiple strings per cache level per CPU. Using io.h's io__getline() avoids the wasted memory as strings are temporarily read into a buffer on the stack before being copied to a buffer that grows 128 bytes at a time and is never sized larger than the string. For a 16 hyperthread system the memory consumption of "perf record true" is reduced by 180kb, primarily through saving memory when reading the cache information. Signed-off-by: Ian Rogers <irogers@google.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Athira Jajeev <atrajeev@linux.vnet.ibm.com> Cc: Changbin Du <changbin.du@huawei.com> Cc: Colin Ian King <colin.i.king@gmail.com> Cc: Dmitrii Dolgov <9erthalion6@gmail.com> Cc: German Gomez <german.gomez@arm.com> Cc: Guilherme Amadio <amadio@gentoo.org> Cc: Huacai Chen <chenhuacai@kernel.org> 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: Kajol Jain <kjain@linux.ibm.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Leo Yan <leo.yan@linaro.org> Cc: Li Dong <lidong@vivo.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Masami Hiramatsu (Google) <mhiramat@kernel.org> Cc: Miguel Ojeda <ojeda@kernel.org> Cc: Ming Wang <wangming01@loongson.cn> Cc: Nick Terrell <terrelln@fb.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi Bangoria <ravi.bangoria@amd.com> Cc: Sandipan Das <sandipan.das@amd.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Steinar H. Gunderson <sesse@google.com> Cc: Vincent Whitchurch <vincent.whitchurch@axis.com> Cc: Wenyu Liu <liuwenyu7@huawei.com> Cc: Yang Jihong <yangjihong1@huawei.com> Link: https://lore.kernel.org/r/20231127220902.1315692-5-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-11-27 14:08:16 -08:00
tools api: Add io__getline Reads a line to allocated memory up to a newline following the getline API. Committer notes: It also adds this new function to the 'api io' 'perf test' entry: $ perf test "api io" 64: Test api io : Ok $ Signed-off-by: Ian Rogers <irogers@google.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Acked-by: Namhyung Kim <namhyung@kernel.org> 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: Nathan Chancellor <nathan@kernel.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Tom Rix <trix@redhat.com> Cc: llvm@lists.linux.dev Link: https://lore.kernel.org/r/20230403184033.1836023-2-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-04-03 11:40:30 -07:00
tools api: Avoid potential double free io__getline will free the line on error but it doesn't clear the out argument. This may lead to the line being freed twice, like in tools/perf/util/srcline.c as detected by clang-tidy. Signed-off-by: Ian Rogers <irogers@google.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Cc: Ravi Bangoria <ravi.bangoria@amd.com> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Yang Jihong <yangjihong1@huawei.com> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: Nathan Chancellor <nathan@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: llvm@lists.linux.dev Cc: Ming Wang <wangming01@loongson.cn> Cc: Tom Rix <trix@redhat.com> Cc: bpf@vger.kernel.org Link: https://lore.kernel.org/r/20231009183920.200859-17-irogers@google.com Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2023-10-09 11:39:17 -07:00
tools api io: Ensure line_len_out is always initialized Ensure initialization to avoid compiler warnings about potential use of uninitialized variables. Signed-off-by: Ian Rogers <irogers@google.com> Cc: Ravi Bangoria <ravi.bangoria@amd.com> Cc: Yoshihiro Furudera <fj5100bi@fujitsu.com> Cc: Howard Chu <howardchu95@gmail.com> Cc: Ze Gao <zegao2021@gmail.com> Cc: Changbin Du <changbin.du@huawei.com> Cc: Junhao He <hejunhao3@huawei.com> Cc: Weilin Wang <weilin.wang@intel.com> Cc: James Clark <james.clark@linaro.org> Cc: Oliver Upton <oliver.upton@linux.dev> Cc: Athira Jajeev <atrajeev@linux.vnet.ibm.com> Link: https://lore.kernel.org/r/20241109003759.473460-2-irogers@google.com Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2024-11-08 16:37:53 -08:00
tools api: Add io__getline Reads a line to allocated memory up to a newline following the getline API. Committer notes: It also adds this new function to the 'api io' 'perf test' entry: $ perf test "api io" 64: Test api io : Ok $ Signed-off-by: Ian Rogers <irogers@google.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Acked-by: Namhyung Kim <namhyung@kernel.org> 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: Nathan Chancellor <nathan@kernel.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Tom Rix <trix@redhat.com> Cc: llvm@lists.linux.dev Link: https://lore.kernel.org/r/20230403184033.1836023-2-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-04-03 11:40:30 -07:00
tools api fs: Switch filename__read_str to use io.h filename__read_str() has its own string reading code that allocates memory before reading into it. The memory allocated is sized at BUFSIZ that is 8kb. Most strings are short and so most of this 8kb is wasted. Refactor io__getline(), as io__getdelim(), so that the newline character can be configurable and ignored in the case of filename__read_str(). Code like build_caches_for_cpu() in perf's header.c will read many strings and hold them in a data structure, in this case multiple strings per cache level per CPU. Using io.h's io__getline() avoids the wasted memory as strings are temporarily read into a buffer on the stack before being copied to a buffer that grows 128 bytes at a time and is never sized larger than the string. For a 16 hyperthread system the memory consumption of "perf record true" is reduced by 180kb, primarily through saving memory when reading the cache information. Signed-off-by: Ian Rogers <irogers@google.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Athira Jajeev <atrajeev@linux.vnet.ibm.com> Cc: Changbin Du <changbin.du@huawei.com> Cc: Colin Ian King <colin.i.king@gmail.com> Cc: Dmitrii Dolgov <9erthalion6@gmail.com> Cc: German Gomez <german.gomez@arm.com> Cc: Guilherme Amadio <amadio@gentoo.org> Cc: Huacai Chen <chenhuacai@kernel.org> 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: Kajol Jain <kjain@linux.ibm.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Leo Yan <leo.yan@linaro.org> Cc: Li Dong <lidong@vivo.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Masami Hiramatsu (Google) <mhiramat@kernel.org> Cc: Miguel Ojeda <ojeda@kernel.org> Cc: Ming Wang <wangming01@loongson.cn> Cc: Nick Terrell <terrelln@fb.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi Bangoria <ravi.bangoria@amd.com> Cc: Sandipan Das <sandipan.das@amd.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Steinar H. Gunderson <sesse@google.com> Cc: Vincent Whitchurch <vincent.whitchurch@axis.com> Cc: Wenyu Liu <liuwenyu7@huawei.com> Cc: Yang Jihong <yangjihong1@huawei.com> Link: https://lore.kernel.org/r/20231127220902.1315692-5-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-11-27 14:08:16 -08:00
tools api: Add a lightweight buffered reading api The synthesize benchmark shows the majority of execution time going to fgets and sscanf, necessary to parse /proc/pid/maps. Add a new buffered reading library that will be used to replace these calls in a follow-up CL. Add tests for the library to perf test. Committer tests: $ perf test api 63: Test api io : Ok $ Signed-off-by: Ian Rogers <irogers@google.com> Acked-by: Jiri Olsa <jolsa@redhat.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andrey Zhizhikin <andrey.z@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lore.kernel.org/lkml/20200415054050.31645-3-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-14 22:40:49 -07:00