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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-19 10:09:22 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-19 10:09:22 -0700 |
| commit | f4cdf7ca9a1fdcca413157df19753f388a5a224e (patch) | |
| tree | 60a31895b2446cd7fa27514e8c2843534a0de0da /tools/perf/tests/dwarf-unwind.c | |
| download | linux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.tar.gz linux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.zip | |
Merge tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-mediagrafted
Pull media updates from Mauro Carvalho Chehab:
- v4l2-core: added ISP statistics support and per-block validation
- v4l2-core: Allow unknown HDR10 white point and luminance
- New camera sensors: Sony IMX678 and IMX471m, Himax HM1092 IR sensor
- New codec: Milos: VPU v2.0 codec support
- isp driver: gained support for Dreamchip RPPX1 ISP framework
- vsp1 driver: gained support for RZ/T2H and RZ/N2H
- Novalake driver: gained CVS support for new NVL hardware
- dvb-core: fix feed leak on failed DMX_ADD_PID
- several driver fixes, cleanups and minor improvements
* tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (308 commits)
media: ipu-bridge: check all DMI entries when overriding sensor rotation
media: v4l2-async: avoid deleting unlinked ASC entry on link error
media: rzg2l-cru: Align bytesperline to hardware DMA stride requirement
media: intel/ipu6: fix async notifier cleanup leak on parse error
media: staging/ipu7: fix async notifier UAF on probe error path
media: amd: isp4: fix self-deadlock in isp4sd_pwron_and_init() error path
media: amd: isp4: release partial allocations in isp4if_alloc_fw_gpumem()
media: rcar-isp: Fix VSPX reference leaks
media: rcar-isp: Release ISPCORE resources
media: i2c: imx415: Release runtime PM reference on VBLANK error
media: i2c: imx415: Return test pattern write errors
media: renesas: vsp1: Declare index variables in for loop statement
media: renesas: vsp1: Make reset control optional to support platforms without a reset line
media: dt-bindings: media: renesas,vsp1: Document RZ/T2H and RZ/N2H SoCs
media: dt-bindings: media: renesas,fcp: Document RZ/T2H and RZ/N2H SoCs
media: nxp: imx8-isi: Add additional 32-bit RGB format support
media: nxp: imx8-isi: Add 16-bit raw Bayer format support
media: nxp: imx8-isi: Implement per-stream reference counting for multiplexed streams
media: nxp: imx8-isi: Use BIT_ULL() for 64-bit stream masks
media: nxp: imx8-isi: Correct color map between V4L2 and ISI
...
Diffstat (limited to 'tools/perf/tests/dwarf-unwind.c')
| -rw-r--r-- | tools/perf/tests/dwarf-unwind.c | 223 |
1 files changed, 223 insertions, 0 deletions
diff --git a/tools/perf/tests/dwarf-unwind.c b/tools/perf/tests/dwarf-unwind.c new file mode 100644 index 000000000..9ed78d00f --- /dev/null +++ b/tools/perf/tests/dwarf-unwind.c @@ -0,0 +1,223 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <linux/compiler.h> +#include <linux/types.h> +#include <linux/zalloc.h> +#include <inttypes.h> +#include <limits.h> +#include <unistd.h> +#include "tests.h" +#include "debug.h" +#include "env.h" +#include "machine.h" +#include "event.h" +#include "../util/unwind.h" +#include "perf_regs.h" +#include "map.h" +#include "symbol.h" +#include "thread.h" +#include "callchain.h" + +/* For bsearch. We try to unwind functions in shared object. */ +#include <stdlib.h> + +/* + * The test will assert frames are on the stack but tail call optimizations lose + * the frame of the caller. Clang can disable this optimization on a called + * function but GCC currently (11/2020) lacks this attribute. The barrier is + * used to inhibit tail calls in these cases. + */ +#ifdef __has_attribute +#if __has_attribute(disable_tail_calls) +#define NO_TAIL_CALL_ATTRIBUTE __attribute__((disable_tail_calls)) +#define NO_TAIL_CALL_BARRIER +#endif +#endif +#ifndef NO_TAIL_CALL_ATTRIBUTE +#define NO_TAIL_CALL_ATTRIBUTE +#define NO_TAIL_CALL_BARRIER __asm__ __volatile__("" : : : "memory"); +#endif + +/* + * We need to keep these functions global, despite the + * fact that they are used only locally in this object, + * in order to keep them around even if the binary is + * stripped. If they are gone, the unwind check for + * symbol fails. + */ +int test_dwarf_unwind__thread(struct thread *thread); +int test_dwarf_unwind__compare(void *p1, void *p2); +int test_dwarf_unwind__krava_3(struct thread *thread); +int test_dwarf_unwind__krava_2(struct thread *thread); +int test_dwarf_unwind__krava_1(struct thread *thread); +int test__dwarf_unwind(struct test_suite *test, int subtest); + +#define MAX_STACK 8 + +static int unwind_entry(struct unwind_entry *entry, void *arg) +{ + unsigned long *cnt = (unsigned long *) arg; + char *symbol = entry->ms.sym ? entry->ms.sym->name : NULL; + static const char *funcs[MAX_STACK] = { + "test__arch_unwind_sample", + "test_dwarf_unwind__thread", + "test_dwarf_unwind__compare", + "bsearch", + "test_dwarf_unwind__krava_3", + "test_dwarf_unwind__krava_2", + "test_dwarf_unwind__krava_1", + "test__dwarf_unwind" + }; + /* + * The funcs[MAX_STACK] array index, based on the + * callchain order setup. + */ + int idx = callchain_param.order == ORDER_CALLER ? + MAX_STACK - *cnt - 1 : *cnt; + + if (*cnt >= MAX_STACK) { + pr_debug("failed: crossed the max stack value %d\n", MAX_STACK); + return -1; + } + + if (!symbol) { + pr_debug("failed: got unresolved address 0x%" PRIx64 "\n", + entry->ip); + return -1; + } + + (*cnt)++; + pr_debug("got: %s 0x%" PRIx64 ", expecting %s\n", + symbol, entry->ip, funcs[idx]); + return strcmp((const char *) symbol, funcs[idx]); +} + +NO_TAIL_CALL_ATTRIBUTE noinline int test_dwarf_unwind__thread(struct thread *thread) +{ + struct perf_sample sample; + unsigned long cnt = 0; + int err = -1; + + perf_sample__init(&sample, /*all=*/true); + if (test__arch_unwind_sample(&sample, thread)) { + pr_debug("failed to get unwind sample\n"); + goto out; + } + + err = unwind__get_entries(unwind_entry, &cnt, thread, + &sample, MAX_STACK, false); + if (err) + pr_debug("unwind failed\n"); + else if (cnt != MAX_STACK) { + pr_debug("got wrong number of stack entries %lu != %d\n", + cnt, MAX_STACK); + err = -1; + } + + out: + zfree(&sample.user_stack.data); + zfree(&sample.user_regs->regs); + perf_sample__exit(&sample); + return err; +} + +static int global_unwind_retval = -INT_MAX; + +NO_TAIL_CALL_ATTRIBUTE noinline int test_dwarf_unwind__compare(void *p1, void *p2) +{ + /* Any possible value should be 'thread' */ + struct thread *thread = *(struct thread **)p1; + + if (global_unwind_retval == -INT_MAX) { + /* Call unwinder twice for both callchain orders. */ + callchain_param.order = ORDER_CALLER; + + global_unwind_retval = test_dwarf_unwind__thread(thread); + if (!global_unwind_retval) { + callchain_param.order = ORDER_CALLEE; + global_unwind_retval = test_dwarf_unwind__thread(thread); + } + } + + return p1 - p2; +} + +NO_TAIL_CALL_ATTRIBUTE noinline int test_dwarf_unwind__krava_3(struct thread *thread) +{ + struct thread *array[2] = {thread, thread}; + void *fp = &bsearch; + /* + * make _bsearch a volatile function pointer to + * prevent potential optimization, which may expand + * bsearch and call compare directly from this function, + * instead of libc shared object. + */ + void *(*volatile _bsearch)(void *, void *, size_t, + size_t, int (*)(void *, void *)); + + _bsearch = fp; + _bsearch(array, &thread, 2, sizeof(struct thread **), + test_dwarf_unwind__compare); + return global_unwind_retval; +} + +NO_TAIL_CALL_ATTRIBUTE noinline int test_dwarf_unwind__krava_2(struct thread *thread) +{ + int ret; + + ret = test_dwarf_unwind__krava_3(thread); + NO_TAIL_CALL_BARRIER; + return ret; +} + +NO_TAIL_CALL_ATTRIBUTE noinline int test_dwarf_unwind__krava_1(struct thread *thread) +{ + int ret; + + ret = test_dwarf_unwind__krava_2(thread); + NO_TAIL_CALL_BARRIER; + return ret; +} + +noinline int test__dwarf_unwind(struct test_suite *test __maybe_unused, + int subtest __maybe_unused) +{ + struct perf_env host_env; + struct machine *machine; + struct thread *thread; + int err = -1; + pid_t pid = getpid(); + + callchain_param.record_mode = CALLCHAIN_DWARF; + dwarf_callchain_users = true; + + perf_env__init(&host_env); + machine = machine__new_live(&host_env, /*kernel_maps=*/true, pid); + if (!machine) { + pr_err("Could not get machine\n"); + goto out; + } + + if (machine__create_kernel_maps(machine)) { + pr_err("Failed to create kernel maps\n"); + goto out; + } + + if (verbose > 1) + machine__fprintf(machine, stderr); + + thread = machine__find_thread(machine, pid, pid); + if (!thread) { + pr_err("Could not get thread\n"); + goto out; + } + + err = test_dwarf_unwind__krava_1(thread); + thread__put(thread); + + out: + machine__delete(machine); + perf_env__exit(&host_env); + return err; +} + +DEFINE_SUITE("Test dwarf unwind", dwarf_unwind); |
