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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-10-02 12:17:24 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-10-02 12:17:24 -0700 |
| commit | 3f1fe48a36b0b6722dc3fd421d93512bac138e9a (patch) | |
| tree | b767d7f6e26bc64334d3f14f8422d187239dc45d /tools/perf/util/sample.c | |
| download | linux-stable-3f1fe48a36b0b6722dc3fd421d93512bac138e9a.tar.gz linux-stable-3f1fe48a36b0b6722dc3fd421d93512bac138e9a.zip | |
Merge tag 'io_uring-7.3-20261002' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linuxgrafted
Pull io_uring fixes from Jens Axboe:
- Fix a task_work add use-after-free with SQPOLL.
The sqpoll thread could pop and complete the last request while
io_req_normal_work_add() was still looking at them after the mpscq
push.
Use the same approach as DEFER_TASKRUN to protect from that, holding
an RCU read lock across the add, and have exit wait for an RCU grace
period for SQPOLL rings as well.
- CQE32 ring fixes: correct the free entry check for 32b CQEs, zero the
big_cqe for aux CQEs, and only post the dummy skip CQE on CQE_MIXED
rings
- Mark the source filter table as COW when cloning bpf filters, so
registering another filter on the source doesn't modify the shared
table in place
- Initialize the task context before running the BPF loop
- Requeue zcrx multishot receives stopped by a local resource
- End a TX_TIMESTAMP multishot cmd when the CQ is full (lollipopkit)
* tag 'io_uring-7.3-20261002' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux:
io_uring: fix task_work add use-after-free with SQPOLL
io_uring/cmd_net: end TX_TIMESTAMP multishot when the CQ is full
io_uring/zcrx: requeue multishot receives stopped by a local resource
io_uring: initialize task context before running the BPF loop
io_uring: zero big_cqe for aux CQEs on CQE32 rings
io_uring: fix free entry check for 32b CQEs on CQE32 rings
io_uring: only post the dummy skip CQE on CQE_MIXED rings
io_uring/bpf_filter: mark source as COW when cloning filters
Diffstat (limited to 'tools/perf/util/sample.c')
| -rw-r--r-- | tools/perf/util/sample.c | 134 |
1 files changed, 134 insertions, 0 deletions
diff --git a/tools/perf/util/sample.c b/tools/perf/util/sample.c new file mode 100644 index 000000000..bccc19e2a --- /dev/null +++ b/tools/perf/util/sample.c @@ -0,0 +1,134 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#include "sample.h" + +#include <stdlib.h> +#include <string.h> + +#include <elf.h> +#include <linux/zalloc.h> + +#include "../../arch/x86/include/asm/insn.h" +#include "debug.h" +#include "evsel.h" +#include "thread.h" + +#ifndef EM_CSKY +#define EM_CSKY 252 +#endif +#ifndef EM_LOONGARCH +#define EM_LOONGARCH 258 +#endif + +void perf_sample__init(struct perf_sample *sample, bool all) +{ + if (all) { + memset(sample, 0, sizeof(*sample)); + } else { + sample->evsel = NULL; + sample->user_regs = NULL; + sample->intr_regs = NULL; + sample->merged_callchain = false; + sample->callchain = NULL; + } +} + +void perf_sample__exit(struct perf_sample *sample) +{ + evsel__put(sample->evsel); + sample->evsel = NULL; + zfree(&sample->user_regs); + zfree(&sample->intr_regs); + if (sample->merged_callchain) { + zfree(&sample->callchain); + sample->merged_callchain = false; + } +} + +struct regs_dump *perf_sample__user_regs(struct perf_sample *sample) +{ + if (!sample->user_regs) { + sample->user_regs = zalloc(sizeof(*sample->user_regs)); + if (!sample->user_regs) + pr_err("Failure to allocate sample user_regs"); + } + return sample->user_regs; +} + + +struct regs_dump *perf_sample__intr_regs(struct perf_sample *sample) +{ + if (!sample->intr_regs) { + sample->intr_regs = zalloc(sizeof(*sample->intr_regs)); + if (!sample->intr_regs) + pr_err("Failure to allocate sample intr_regs"); + } + return sample->intr_regs; +} + +static int elf_machine_max_instruction_length(uint16_t e_machine) +{ + switch (e_machine) { + /* Fixed 4-byte (32-bit) architectures */ + case EM_AARCH64: + case EM_PPC: + case EM_PPC64: + case EM_MIPS: + case EM_SPARC: + case EM_SPARCV9: + case EM_ALPHA: + case EM_LOONGARCH: + case EM_PARISC: + case EM_SH: + return 4; + + /* Variable length or mixed-mode architectures */ + case EM_ARM: /* Variable due to Thumb/Thumb-2 */ + case EM_RISCV: /* Variable due to Compressed (C) extension */ + case EM_CSKY: /* Variable (16 or 32 bit) */ + case EM_ARC: /* Variable (ARCompact) */ + return 4; + case EM_S390: /* Variable (2, 4, or 6 bytes) */ + return 6; + case EM_68K: + return 10; + case EM_386: + case EM_X86_64: + return 15; + case EM_XTENSA: /* Variable (FLIX) */ + return 16; + default: + return MAX_INSN; + } +} + +void perf_sample__fetch_insn(struct perf_sample *sample, + struct thread *thread, + struct machine *machine) +{ + int ret, len; + bool is64bit = false; + uint16_t e_machine; + + if (!sample->ip || sample->insn_len != 0) + return; + + e_machine = thread__e_machine(thread, machine, /*e_flags=*/NULL); + len = elf_machine_max_instruction_length(e_machine); + len = thread__memcpy(thread, machine, sample->insn, + sample->ip, len, + &is64bit); + if (len <= 0) + return; + + sample->insn_len = len; + + if (e_machine == EM_386 || e_machine == EM_X86_64) { + /* Refine the x86 instruction length with the decoder. */ + struct insn insn; + + ret = insn_decode(&insn, sample->insn, len, + is64bit ? INSN_MODE_64 : INSN_MODE_32); + if (ret >= 0 && insn.length <= len) + sample->insn_len = insn.length; + } +} |
