From 5febf432df1cfa5b25d99b54c32103fafbdd0eb9 Mon Sep 17 00:00:00 2001 From: Miguel Ojeda Date: Sun, 16 Aug 2026 15:32:33 +0200 Subject: kbuild: rust: keep Rust objects out of Clang LTO with inline helpers Under `CONFIG_LTO_CLANG` + `CONFIG_RUST_INLINE_HELPERS`, one may hit `objtool` errors such as: vmlinux.o: error: objtool: _R..._3Gsp4boot+0xd6a: can't find jump dest instruction at .text._R..._3Gsp4boot+0x1dfd The reason is that in such builds, the Clang invocation that compiles the combined Rust plus helpers bitcode emits LLVM bitcode (again) -- the final code generation happens in the linker's LTO step, which the `-mllvm` trap options passed to Clang do not reach. This, in turn, means that unreachable traps are missing, and the impossible paths do not merely fallthrough to the next symbol, but past the end of their own section, since LTO builds place each function in its own section. Thus filter `CC_FLAGS_LTO` out of the Clang invocation, so that it always emits machine code directly, with the traps in place. Assisted-by: LLM Cc: Gary Guo Cc: Boqun Feng Cc: Alice Ryhl Cc: Matthew Maurer Cc: Josh Poimboeuf Cc: Peter Zijlstra Cc: stable@vger.kernel.org Fixes: 3a2486cc1da5 ("kbuild: rust: provide an option to inline C helpers into Rust") Acked-by: Gary Guo Link: https://patch.msgid.link/20260816133233.197500-2-ojeda@kernel.org Signed-off-by: Miguel Ojeda --- include/trace/events/fscache.h | 507 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 507 insertions(+) create mode 100644 include/trace/events/fscache.h (limited to 'include/trace/events/fscache.h') diff --git a/include/trace/events/fscache.h b/include/trace/events/fscache.h new file mode 100644 index 000000000..f1a73aa83 --- /dev/null +++ b/include/trace/events/fscache.h @@ -0,0 +1,507 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* FS-Cache tracepoints + * + * Copyright (C) 2021 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ +#undef TRACE_SYSTEM +#define TRACE_SYSTEM fscache + +#if !defined(_TRACE_FSCACHE_H) || defined(TRACE_HEADER_MULTI_READ) +#define _TRACE_FSCACHE_H + +#include +#include + +/* + * Define enums for tracing information. + */ +#ifndef __FSCACHE_DECLARE_TRACE_ENUMS_ONCE_ONLY +#define __FSCACHE_DECLARE_TRACE_ENUMS_ONCE_ONLY + +enum fscache_cache_trace { + fscache_cache_collision, + fscache_cache_get_acquire, + fscache_cache_new_acquire, + fscache_cache_put_alloc_volume, + fscache_cache_put_cache, + fscache_cache_put_prep_failed, + fscache_cache_put_relinquish, + fscache_cache_put_volume, +}; + +enum fscache_volume_trace { + fscache_volume_collision, + fscache_volume_get_cookie, + fscache_volume_get_create_work, + fscache_volume_get_hash_collision, + fscache_volume_get_withdraw, + fscache_volume_free, + fscache_volume_new_acquire, + fscache_volume_put_cookie, + fscache_volume_put_create_work, + fscache_volume_put_hash_collision, + fscache_volume_put_relinquish, + fscache_volume_put_withdraw, + fscache_volume_see_create_work, + fscache_volume_see_hash_wake, + fscache_volume_wait_create_work, +}; + +enum fscache_cookie_trace { + fscache_cookie_collision, + fscache_cookie_discard, + fscache_cookie_failed, + fscache_cookie_get_attach_object, + fscache_cookie_get_end_access, + fscache_cookie_get_hash_collision, + fscache_cookie_get_inval_work, + fscache_cookie_get_lru, + fscache_cookie_get_use_work, + fscache_cookie_new_acquire, + fscache_cookie_put_hash_collision, + fscache_cookie_put_lru, + fscache_cookie_put_object, + fscache_cookie_put_over_queued, + fscache_cookie_put_relinquish, + fscache_cookie_put_withdrawn, + fscache_cookie_put_work, + fscache_cookie_see_active, + fscache_cookie_see_lru_discard, + fscache_cookie_see_lru_discard_clear, + fscache_cookie_see_lru_do_one, + fscache_cookie_see_relinquish, + fscache_cookie_see_withdraw, + fscache_cookie_see_work, +}; + +enum fscache_active_trace { + fscache_active_use, + fscache_active_use_modify, + fscache_active_unuse, +}; + +enum fscache_access_trace { + fscache_access_acquire_volume, + fscache_access_acquire_volume_end, + fscache_access_cache_pin, + fscache_access_cache_unpin, + fscache_access_invalidate_cookie, + fscache_access_invalidate_cookie_end, + fscache_access_io_end, + fscache_access_io_not_live, + fscache_access_io_read, + fscache_access_io_resize, + fscache_access_io_wait, + fscache_access_io_write, + fscache_access_lookup_cookie, + fscache_access_lookup_cookie_end, + fscache_access_lookup_cookie_end_failed, + fscache_access_relinquish_volume, + fscache_access_relinquish_volume_end, + fscache_access_unlive, +}; + +#endif + +/* + * Declare tracing information enums and their string mappings for display. + */ +#define fscache_cache_traces \ + EM(fscache_cache_collision, "*COLLIDE*") \ + EM(fscache_cache_get_acquire, "GET acq ") \ + EM(fscache_cache_new_acquire, "NEW acq ") \ + EM(fscache_cache_put_alloc_volume, "PUT alvol") \ + EM(fscache_cache_put_cache, "PUT cache") \ + EM(fscache_cache_put_prep_failed, "PUT pfail") \ + EM(fscache_cache_put_relinquish, "PUT relnq") \ + E_(fscache_cache_put_volume, "PUT vol ") + +#define fscache_volume_traces \ + EM(fscache_volume_collision, "*COLLIDE*") \ + EM(fscache_volume_get_cookie, "GET cook ") \ + EM(fscache_volume_get_create_work, "GET creat") \ + EM(fscache_volume_get_hash_collision, "GET hcoll") \ + EM(fscache_volume_get_withdraw, "GET withd") \ + EM(fscache_volume_free, "FREE ") \ + EM(fscache_volume_new_acquire, "NEW acq ") \ + EM(fscache_volume_put_cookie, "PUT cook ") \ + EM(fscache_volume_put_create_work, "PUT creat") \ + EM(fscache_volume_put_hash_collision, "PUT hcoll") \ + EM(fscache_volume_put_relinquish, "PUT relnq") \ + EM(fscache_volume_put_withdraw, "PUT withd") \ + EM(fscache_volume_see_create_work, "SEE creat") \ + EM(fscache_volume_see_hash_wake, "SEE hwake") \ + E_(fscache_volume_wait_create_work, "WAIT crea") + +#define fscache_cookie_traces \ + EM(fscache_cookie_collision, "*COLLIDE*") \ + EM(fscache_cookie_discard, "DISCARD ") \ + EM(fscache_cookie_failed, "FAILED ") \ + EM(fscache_cookie_get_attach_object, "GET attch") \ + EM(fscache_cookie_get_hash_collision, "GET hcoll") \ + EM(fscache_cookie_get_end_access, "GQ endac") \ + EM(fscache_cookie_get_inval_work, "GQ inval") \ + EM(fscache_cookie_get_lru, "GET lru ") \ + EM(fscache_cookie_get_use_work, "GQ use ") \ + EM(fscache_cookie_new_acquire, "NEW acq ") \ + EM(fscache_cookie_put_hash_collision, "PUT hcoll") \ + EM(fscache_cookie_put_lru, "PUT lru ") \ + EM(fscache_cookie_put_object, "PUT obj ") \ + EM(fscache_cookie_put_over_queued, "PQ overq") \ + EM(fscache_cookie_put_relinquish, "PUT relnq") \ + EM(fscache_cookie_put_withdrawn, "PUT wthdn") \ + EM(fscache_cookie_put_work, "PQ work ") \ + EM(fscache_cookie_see_active, "- activ") \ + EM(fscache_cookie_see_lru_discard, "- x-lru") \ + EM(fscache_cookie_see_lru_discard_clear,"- lrudc") \ + EM(fscache_cookie_see_lru_do_one, "- lrudo") \ + EM(fscache_cookie_see_relinquish, "- x-rlq") \ + EM(fscache_cookie_see_withdraw, "- x-wth") \ + E_(fscache_cookie_see_work, "- work ") + +#define fscache_active_traces \ + EM(fscache_active_use, "USE ") \ + EM(fscache_active_use_modify, "USE-m ") \ + E_(fscache_active_unuse, "UNUSE ") + +#define fscache_access_traces \ + EM(fscache_access_acquire_volume, "BEGIN acq_vol") \ + EM(fscache_access_acquire_volume_end, "END acq_vol") \ + EM(fscache_access_cache_pin, "PIN cache ") \ + EM(fscache_access_cache_unpin, "UNPIN cache ") \ + EM(fscache_access_invalidate_cookie, "BEGIN inval ") \ + EM(fscache_access_invalidate_cookie_end,"END inval ") \ + EM(fscache_access_io_end, "END io ") \ + EM(fscache_access_io_not_live, "END io_notl") \ + EM(fscache_access_io_read, "BEGIN io_read") \ + EM(fscache_access_io_resize, "BEGIN io_resz") \ + EM(fscache_access_io_wait, "WAIT io ") \ + EM(fscache_access_io_write, "BEGIN io_writ") \ + EM(fscache_access_lookup_cookie, "BEGIN lookup ") \ + EM(fscache_access_lookup_cookie_end, "END lookup ") \ + EM(fscache_access_lookup_cookie_end_failed,"END lookupf") \ + EM(fscache_access_relinquish_volume, "BEGIN rlq_vol") \ + EM(fscache_access_relinquish_volume_end,"END rlq_vol") \ + E_(fscache_access_unlive, "END unlive ") + +/* + * Export enum symbols via userspace. + */ +#undef EM +#undef E_ +#define EM(a, b) TRACE_DEFINE_ENUM(a); +#define E_(a, b) TRACE_DEFINE_ENUM(a); + +fscache_cache_traces; +fscache_volume_traces; +fscache_cookie_traces; +fscache_access_traces; + +/* + * Now redefine the EM() and E_() macros to map the enums to the strings that + * will be printed in the output. + */ +#undef EM +#undef E_ +#define EM(a, b) { a, b }, +#define E_(a, b) { a, b } + + +TRACE_EVENT(fscache_cache, + TP_PROTO(unsigned int cache_debug_id, + int usage, + enum fscache_cache_trace where), + + TP_ARGS(cache_debug_id, usage, where), + + TP_STRUCT__entry( + __field(unsigned int, cache ) + __field(int, usage ) + __field(enum fscache_cache_trace, where ) + ), + + TP_fast_assign( + __entry->cache = cache_debug_id; + __entry->usage = usage; + __entry->where = where; + ), + + TP_printk("C=%08x %s r=%d", + __entry->cache, + __print_symbolic(__entry->where, fscache_cache_traces), + __entry->usage) + ); + +TRACE_EVENT(fscache_volume, + TP_PROTO(unsigned int volume_debug_id, + int usage, + enum fscache_volume_trace where), + + TP_ARGS(volume_debug_id, usage, where), + + TP_STRUCT__entry( + __field(unsigned int, volume ) + __field(int, usage ) + __field(enum fscache_volume_trace, where ) + ), + + TP_fast_assign( + __entry->volume = volume_debug_id; + __entry->usage = usage; + __entry->where = where; + ), + + TP_printk("V=%08x %s u=%d", + __entry->volume, + __print_symbolic(__entry->where, fscache_volume_traces), + __entry->usage) + ); + +TRACE_EVENT(fscache_cookie, + TP_PROTO(unsigned int cookie_debug_id, + int ref, + enum fscache_cookie_trace where), + + TP_ARGS(cookie_debug_id, ref, where), + + TP_STRUCT__entry( + __field(unsigned int, cookie ) + __field(int, ref ) + __field(enum fscache_cookie_trace, where ) + ), + + TP_fast_assign( + __entry->cookie = cookie_debug_id; + __entry->ref = ref; + __entry->where = where; + ), + + TP_printk("c=%08x %s r=%d", + __entry->cookie, + __print_symbolic(__entry->where, fscache_cookie_traces), + __entry->ref) + ); + +TRACE_EVENT(fscache_active, + TP_PROTO(unsigned int cookie_debug_id, + int ref, + int n_active, + int n_accesses, + enum fscache_active_trace why), + + TP_ARGS(cookie_debug_id, ref, n_active, n_accesses, why), + + TP_STRUCT__entry( + __field(unsigned int, cookie ) + __field(int, ref ) + __field(int, n_active ) + __field(int, n_accesses ) + __field(enum fscache_active_trace, why ) + ), + + TP_fast_assign( + __entry->cookie = cookie_debug_id; + __entry->ref = ref; + __entry->n_active = n_active; + __entry->n_accesses = n_accesses; + __entry->why = why; + ), + + TP_printk("c=%08x %s r=%d a=%d c=%d", + __entry->cookie, + __print_symbolic(__entry->why, fscache_active_traces), + __entry->ref, + __entry->n_accesses, + __entry->n_active) + ); + +TRACE_EVENT(fscache_access_cache, + TP_PROTO(unsigned int cache_debug_id, + int ref, + int n_accesses, + enum fscache_access_trace why), + + TP_ARGS(cache_debug_id, ref, n_accesses, why), + + TP_STRUCT__entry( + __field(unsigned int, cache ) + __field(int, ref ) + __field(int, n_accesses ) + __field(enum fscache_access_trace, why ) + ), + + TP_fast_assign( + __entry->cache = cache_debug_id; + __entry->ref = ref; + __entry->n_accesses = n_accesses; + __entry->why = why; + ), + + TP_printk("C=%08x %s r=%d a=%d", + __entry->cache, + __print_symbolic(__entry->why, fscache_access_traces), + __entry->ref, + __entry->n_accesses) + ); + +TRACE_EVENT(fscache_access_volume, + TP_PROTO(unsigned int volume_debug_id, + unsigned int cookie_debug_id, + int ref, + int n_accesses, + enum fscache_access_trace why), + + TP_ARGS(volume_debug_id, cookie_debug_id, ref, n_accesses, why), + + TP_STRUCT__entry( + __field(unsigned int, volume ) + __field(unsigned int, cookie ) + __field(int, ref ) + __field(int, n_accesses ) + __field(enum fscache_access_trace, why ) + ), + + TP_fast_assign( + __entry->volume = volume_debug_id; + __entry->cookie = cookie_debug_id; + __entry->ref = ref; + __entry->n_accesses = n_accesses; + __entry->why = why; + ), + + TP_printk("V=%08x c=%08x %s r=%d a=%d", + __entry->volume, + __entry->cookie, + __print_symbolic(__entry->why, fscache_access_traces), + __entry->ref, + __entry->n_accesses) + ); + +TRACE_EVENT(fscache_access, + TP_PROTO(unsigned int cookie_debug_id, + int ref, + int n_accesses, + enum fscache_access_trace why), + + TP_ARGS(cookie_debug_id, ref, n_accesses, why), + + TP_STRUCT__entry( + __field(unsigned int, cookie ) + __field(int, ref ) + __field(int, n_accesses ) + __field(enum fscache_access_trace, why ) + ), + + TP_fast_assign( + __entry->cookie = cookie_debug_id; + __entry->ref = ref; + __entry->n_accesses = n_accesses; + __entry->why = why; + ), + + TP_printk("c=%08x %s r=%d a=%d", + __entry->cookie, + __print_symbolic(__entry->why, fscache_access_traces), + __entry->ref, + __entry->n_accesses) + ); + +TRACE_EVENT(fscache_acquire, + TP_PROTO(struct fscache_cookie *cookie), + + TP_ARGS(cookie), + + TP_STRUCT__entry( + __field(unsigned int, cookie ) + __field(unsigned int, volume ) + __field(int, v_ref ) + __field(int, v_n_cookies ) + ), + + TP_fast_assign( + __entry->cookie = cookie->debug_id; + __entry->volume = cookie->volume->debug_id; + __entry->v_ref = refcount_read(&cookie->volume->ref); + __entry->v_n_cookies = atomic_read(&cookie->volume->n_cookies); + ), + + TP_printk("c=%08x V=%08x vr=%d vc=%d", + __entry->cookie, + __entry->volume, __entry->v_ref, __entry->v_n_cookies) + ); + +TRACE_EVENT(fscache_relinquish, + TP_PROTO(struct fscache_cookie *cookie, bool retire), + + TP_ARGS(cookie, retire), + + TP_STRUCT__entry( + __field(unsigned int, cookie ) + __field(unsigned int, volume ) + __field(int, ref ) + __field(int, n_active ) + __field(u8, flags ) + __field(bool, retire ) + ), + + TP_fast_assign( + __entry->cookie = cookie->debug_id; + __entry->volume = cookie->volume->debug_id; + __entry->ref = refcount_read(&cookie->ref); + __entry->n_active = atomic_read(&cookie->n_active); + __entry->flags = cookie->flags; + __entry->retire = retire; + ), + + TP_printk("c=%08x V=%08x r=%d U=%d f=%02x rt=%u", + __entry->cookie, __entry->volume, __entry->ref, + __entry->n_active, __entry->flags, __entry->retire) + ); + +TRACE_EVENT(fscache_invalidate, + TP_PROTO(struct fscache_cookie *cookie, loff_t new_size), + + TP_ARGS(cookie, new_size), + + TP_STRUCT__entry( + __field(unsigned int, cookie ) + __field(loff_t, new_size ) + ), + + TP_fast_assign( + __entry->cookie = cookie->debug_id; + __entry->new_size = new_size; + ), + + TP_printk("c=%08x sz=%llx", + __entry->cookie, __entry->new_size) + ); + +TRACE_EVENT(fscache_resize, + TP_PROTO(struct fscache_cookie *cookie, loff_t new_size), + + TP_ARGS(cookie, new_size), + + TP_STRUCT__entry( + __field(unsigned int, cookie ) + __field(loff_t, old_size ) + __field(loff_t, new_size ) + ), + + TP_fast_assign( + __entry->cookie = cookie->debug_id; + __entry->old_size = cookie->object_size; + __entry->new_size = new_size; + ), + + TP_printk("c=%08x os=%08llx sz=%08llx", + __entry->cookie, + __entry->old_size, + __entry->new_size) + ); + +#endif /* _TRACE_FSCACHE_H */ + +/* This part must be outside protection */ +#include -- cgit v1.3.1