diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-23 13:28:57 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-23 13:28:57 -0700 |
| commit | 4352b8aee98005853aa63f57d6377282de17a33f (patch) | |
| tree | 27614d7a9ef05c32d089004e104364ce42324837 /tools/perf/bench/breakpoint.c | |
| download | linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip | |
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni:
"A new driver this cycle, for the AMD AXI I3C controller.
There are also new features such as IBI wakeup support, SETAASA device
discovery and ACPI support for the the DAA methods, meaning we can now
communicate with the SPD devices on DDR5 modules.
New driver:
- AMD AXI I3C master controller
Subsystem:
- I3C Common Command Code (CCC) handling improvements, especially
around GET CCCs
- SETAASA device discovery support
- ACPI support for all existing DAA methods like SETDASA, SETNEWDA as
well as I2C devices on I3C bus
- IBI-based wakeup support
Drivers:
- dw: SETAASA support
- mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C
controller support, PIO queue management support for HCI v1.2
- renesas: improve suspend to RAM support, add runtime PM support"
* tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits)
i3c: dw: reduce do_daa time if there's no client
i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller
i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2
i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode
i3c: dw: rename "pclk" to "apb" to match dt-binding
i3c: dw: make struct dw_i3c_cmd smaller
i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding
i3c: renesas: Don't register devices when ENTDAA times out
i3c: master: dw-i3c-master: fix OD timing for first broadcast
i3c: mipi-i3c-hci: Advertise IBI wakeup capability
i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev()
i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI
i3c: master: Reject IBI requests from non-IBI-capable devices
i3c: master: Add helper to query bus wakeup requirements
i3c: master: Report wakeup events for IBIs
i3c: master: Support IBI-based wakeup capability
i3c: master: Fix potential UAF in i3c_device_match()
i3c: master: Fix potential UAF in i3c_device_uevent()
i3c: Make dev->desc locking assumptions explicit
i3c: master: Fix use-after-free of master->this
...
Diffstat (limited to 'tools/perf/bench/breakpoint.c')
| -rw-r--r-- | tools/perf/bench/breakpoint.c | 262 |
1 files changed, 262 insertions, 0 deletions
diff --git a/tools/perf/bench/breakpoint.c b/tools/perf/bench/breakpoint.c new file mode 100644 index 000000000..1b7cd4481 --- /dev/null +++ b/tools/perf/bench/breakpoint.c @@ -0,0 +1,262 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <subcmd/parse-options.h> +#include <linux/hw_breakpoint.h> +#include <linux/perf_event.h> +#include <linux/time64.h> +#include <sys/syscall.h> +#include <sys/ioctl.h> +#include <sys/time.h> +#include <pthread.h> +#include <stddef.h> +#include <stdlib.h> +#include <unistd.h> +#include <stdio.h> +#include <errno.h> +#include "bench.h" +#include "futex.h" + +static struct { + unsigned int nbreakpoints; + unsigned int nparallel; + unsigned int nthreads; +} thread_params = { + .nbreakpoints = 1, + .nparallel = 1, + .nthreads = 1, +}; + +static const struct option thread_options[] = { + OPT_UINTEGER('b', "breakpoints", &thread_params.nbreakpoints, + "Specify amount of breakpoints"), + OPT_UINTEGER('p', "parallelism", &thread_params.nparallel, "Specify amount of parallelism"), + OPT_UINTEGER('t', "threads", &thread_params.nthreads, "Specify amount of threads"), + OPT_END() +}; + +static const char * const thread_usage[] = { + "perf bench breakpoint thread <options>", + NULL +}; + +struct breakpoint { + int fd; + char watched; +}; + +static int breakpoint_setup(void *addr) +{ + struct perf_event_attr attr = { .size = 0, }; + int fd; + + attr.type = PERF_TYPE_BREAKPOINT; + attr.size = sizeof(attr); + attr.inherit = 1; + attr.exclude_kernel = 1; + attr.exclude_hv = 1; + attr.bp_addr = (unsigned long)addr; + attr.bp_type = HW_BREAKPOINT_RW; + attr.bp_len = HW_BREAKPOINT_LEN_1; + fd = syscall(SYS_perf_event_open, &attr, 0, -1, -1, 0); + + if (fd < 0) + fd = -errno; + + return fd; +} + +static void *passive_thread(void *arg) +{ + unsigned int *done = (unsigned int *)arg; + + while (!__atomic_load_n(done, __ATOMIC_RELAXED)) + futex_wait(done, 0, NULL, 0); + return NULL; +} + +static void *active_thread(void *arg) +{ + unsigned int *done = (unsigned int *)arg; + + while (!__atomic_load_n(done, __ATOMIC_RELAXED)); + return NULL; +} + +static void *breakpoint_thread(void *arg) +{ + unsigned int i, done; + int *repeat = (int *)arg; + pthread_t *threads; + + threads = calloc(thread_params.nthreads, sizeof(threads[0])); + if (!threads) + exit((perror("calloc"), EXIT_FAILURE)); + + while (__atomic_fetch_sub(repeat, 1, __ATOMIC_RELAXED) > 0) { + done = 0; + for (i = 0; i < thread_params.nthreads; i++) { + if (pthread_create(&threads[i], NULL, passive_thread, &done)) + exit((perror("pthread_create"), EXIT_FAILURE)); + } + __atomic_store_n(&done, 1, __ATOMIC_RELAXED); + futex_wake(&done, thread_params.nthreads, 0); + for (i = 0; i < thread_params.nthreads; i++) + pthread_join(threads[i], NULL); + } + free(threads); + return NULL; +} + +// The benchmark creates nbreakpoints inheritable breakpoints, +// then starts nparallel threads which create and join bench_repeat batches of nthreads threads. +int bench_breakpoint_thread(int argc, const char **argv) +{ + unsigned int i, result_usec; + int repeat = bench_repeat; + struct breakpoint *breakpoints; + pthread_t *parallel; + struct timeval start, stop, diff; + + if (parse_options(argc, argv, thread_options, thread_usage, 0)) { + usage_with_options(thread_usage, thread_options); + exit(EXIT_FAILURE); + } + breakpoints = calloc(thread_params.nbreakpoints, sizeof(breakpoints[0])); + parallel = calloc(thread_params.nparallel, sizeof(parallel[0])); + if (!breakpoints || !parallel) + exit((perror("calloc"), EXIT_FAILURE)); + + for (i = 0; i < thread_params.nbreakpoints; i++) { + breakpoints[i].fd = breakpoint_setup(&breakpoints[i].watched); + + if (breakpoints[i].fd < 0) { + if (breakpoints[i].fd == -ENODEV) { + printf("Skipping perf bench breakpoint thread: No hardware support\n"); + return 0; + } + exit((perror("perf_event_open"), EXIT_FAILURE)); + } + } + gettimeofday(&start, NULL); + for (i = 0; i < thread_params.nparallel; i++) { + if (pthread_create(¶llel[i], NULL, breakpoint_thread, &repeat)) + exit((perror("pthread_create"), EXIT_FAILURE)); + } + for (i = 0; i < thread_params.nparallel; i++) + pthread_join(parallel[i], NULL); + gettimeofday(&stop, NULL); + timersub(&stop, &start, &diff); + for (i = 0; i < thread_params.nbreakpoints; i++) + close(breakpoints[i].fd); + free(parallel); + free(breakpoints); + switch (bench_format) { + case BENCH_FORMAT_DEFAULT: + printf("# Created/joined %d threads with %d breakpoints and %d parallelism\n", + bench_repeat, thread_params.nbreakpoints, thread_params.nparallel); + printf(" %14s: %lu.%03lu [sec]\n\n", "Total time", + (long)diff.tv_sec, (long)(diff.tv_usec / USEC_PER_MSEC)); + result_usec = diff.tv_sec * USEC_PER_SEC + diff.tv_usec; + printf(" %14lf usecs/op\n", + (double)result_usec / bench_repeat / thread_params.nthreads); + printf(" %14lf usecs/op/cpu\n", + (double)result_usec / bench_repeat / + thread_params.nthreads * thread_params.nparallel); + break; + case BENCH_FORMAT_SIMPLE: + printf("%lu.%03lu\n", (long)diff.tv_sec, (long)(diff.tv_usec / USEC_PER_MSEC)); + break; + default: + fprintf(stderr, "Unknown format: %d\n", bench_format); + exit(EXIT_FAILURE); + } + return 0; +} + +static struct { + unsigned int npassive; + unsigned int nactive; +} enable_params = { + .nactive = 0, + .npassive = 0, +}; + +static const struct option enable_options[] = { + OPT_UINTEGER('p', "passive", &enable_params.npassive, "Specify amount of passive threads"), + OPT_UINTEGER('a', "active", &enable_params.nactive, "Specify amount of active threads"), + OPT_END() +}; + +static const char * const enable_usage[] = { + "perf bench breakpoint enable <options>", + NULL +}; + +// The benchmark creates an inheritable breakpoint, +// then starts npassive threads that block and nactive threads that actively spin +// and then disables and enables the breakpoint bench_repeat times. +int bench_breakpoint_enable(int argc, const char **argv) +{ + unsigned int i, nthreads, result_usec, done = 0; + char watched; + int fd; + pthread_t *threads; + struct timeval start, stop, diff; + + if (parse_options(argc, argv, enable_options, enable_usage, 0)) { + usage_with_options(enable_usage, enable_options); + exit(EXIT_FAILURE); + } + fd = breakpoint_setup(&watched); + + if (fd < 0) { + if (fd == -ENODEV) { + printf("Skipping perf bench breakpoint enable: No hardware support\n"); + return 0; + } + exit((perror("perf_event_open"), EXIT_FAILURE)); + } + nthreads = enable_params.npassive + enable_params.nactive; + threads = calloc(nthreads, sizeof(threads[0])); + if (!threads) + exit((perror("calloc"), EXIT_FAILURE)); + + for (i = 0; i < nthreads; i++) { + if (pthread_create(&threads[i], NULL, + i < enable_params.npassive ? passive_thread : active_thread, &done)) + exit((perror("pthread_create"), EXIT_FAILURE)); + } + usleep(10000); // let the threads block + gettimeofday(&start, NULL); + for (i = 0; i < bench_repeat; i++) { + if (ioctl(fd, PERF_EVENT_IOC_DISABLE, 0)) + exit((perror("ioctl(PERF_EVENT_IOC_DISABLE)"), EXIT_FAILURE)); + if (ioctl(fd, PERF_EVENT_IOC_ENABLE, 0)) + exit((perror("ioctl(PERF_EVENT_IOC_ENABLE)"), EXIT_FAILURE)); + } + gettimeofday(&stop, NULL); + timersub(&stop, &start, &diff); + __atomic_store_n(&done, 1, __ATOMIC_RELAXED); + futex_wake(&done, enable_params.npassive, 0); + for (i = 0; i < nthreads; i++) + pthread_join(threads[i], NULL); + free(threads); + close(fd); + switch (bench_format) { + case BENCH_FORMAT_DEFAULT: + printf("# Enabled/disabled breakpoint %d time with %d passive and %d active threads\n", + bench_repeat, enable_params.npassive, enable_params.nactive); + printf(" %14s: %lu.%03lu [sec]\n\n", "Total time", + (long)diff.tv_sec, (long)(diff.tv_usec / USEC_PER_MSEC)); + result_usec = diff.tv_sec * USEC_PER_SEC + diff.tv_usec; + printf(" %14lf usecs/op\n", (double)result_usec / bench_repeat); + break; + case BENCH_FORMAT_SIMPLE: + printf("%lu.%03lu\n", (long)diff.tv_sec, (long)(diff.tv_usec / USEC_PER_MSEC)); + break; + default: + fprintf(stderr, "Unknown format: %d\n", bench_format); + exit(EXIT_FAILURE); + } + return 0; +} |
