From: Steven Rostedt <rostedt@goodmis.org>
To: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>,
Mark Rutland <mark.rutland@arm.com>,
Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
Andrew Morton <akpm@linux-foundation.org>,
Josh Poimboeuf <jpoimboe@kernel.org>,
x86@kernel.org, Peter Zijlstra <peterz@infradead.org>,
Ingo Molnar <mingo@kernel.org>,
Arnaldo Carvalho de Melo <acme@kernel.org>,
Indu Bhagat <indu.bhagat@oracle.com>,
Alexander Shishkin <alexander.shishkin@linux.intel.com>,
Jiri Olsa <jolsa@kernel.org>, Namhyung Kim <namhyung@kernel.org>,
Ian Rogers <irogers@google.com>,
Adrian Hunter <adrian.hunter@intel.com>,
linux-perf-users@vger.kernel.org, Mark Brown <broonie@kernel.org>,
linux-toolchains@vger.kernel.org, Jordan Rome <jordalgo@meta.com>,
Sam James <sam@gentoo.org>,
Andrii Nakryiko <andrii.nakryiko@gmail.com>,
Jens Remus <jremus@linux.ibm.com>,
Florian Weimer <fweimer@redhat.com>,
Andy Lutomirski <luto@kernel.org>, Weinan Liu <wnliu@google.com>,
Blake Jones <blakejones@google.com>,
Beau Belgrave <beaub@linux.microsoft.com>,
"Jose E. Marchesi" <jemarch@gnu.org>,
Alexander Aring <aahringo@redhat.com>
Subject: [PATCH v7 12/18] perf: Simplify get_perf_callchain() user logic
Date: Wed, 30 Apr 2025 15:57:58 -0400 [thread overview]
Message-ID: <20250430200109.512005059@goodmis.org> (raw)
In-Reply-To: 20250430195746.827125963@goodmis.org
From: Josh Poimboeuf <jpoimboe@kernel.org>
Simplify the get_perf_callchain() user logic a bit. task_pt_regs()
should never be NULL.
Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
---
kernel/events/callchain.c | 18 ++++++++----------
1 file changed, 8 insertions(+), 10 deletions(-)
diff --git a/kernel/events/callchain.c b/kernel/events/callchain.c
index cda145dc11bd..2798c0c9f782 100644
--- a/kernel/events/callchain.c
+++ b/kernel/events/callchain.c
@@ -247,21 +247,19 @@ get_perf_callchain(struct pt_regs *regs, bool kernel, bool user,
if (user) {
if (!user_mode(regs)) {
if (current->flags & PF_KTHREAD)
- regs = NULL;
- else
- regs = task_pt_regs(current);
+ goto exit_put;
+ regs = task_pt_regs(current);
}
- if (regs) {
- if (add_mark)
- perf_callchain_store_context(&ctx, PERF_CONTEXT_USER);
+ if (add_mark)
+ perf_callchain_store_context(&ctx, PERF_CONTEXT_USER);
- start_entry_idx = entry->nr;
- perf_callchain_user(&ctx, regs);
- fixup_uretprobe_trampoline_entries(entry, start_entry_idx);
- }
+ start_entry_idx = entry->nr;
+ perf_callchain_user(&ctx, regs);
+ fixup_uretprobe_trampoline_entries(entry, start_entry_idx);
}
+exit_put:
put_callchain_entry(rctx);
return entry;
--
2.47.2
next prev parent reply other threads:[~2025-04-30 20:01 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-04-30 19:57 [PATCH v7 00/18] perf: Deferred unwinding of user space stack traces Steven Rostedt
2025-04-30 19:57 ` [PATCH v7 01/18] unwind_user: Add user space unwinding API Steven Rostedt
2025-04-30 19:57 ` [PATCH v7 02/18] unwind_user: Add frame pointer support Steven Rostedt
2025-04-30 19:57 ` [PATCH v7 03/18] unwind_user/x86: Enable frame pointer unwinding on x86 Steven Rostedt
2025-04-30 19:57 ` [PATCH v7 04/18] perf/x86: Rename and move get_segment_base() and make it global Steven Rostedt
2025-04-30 19:57 ` [PATCH v7 05/18] unwind_user: Add compat mode frame pointer support Steven Rostedt
2025-04-30 19:57 ` [PATCH v7 06/18] unwind_user/x86: Enable compat mode frame pointer unwinding on x86 Steven Rostedt
2025-04-30 19:57 ` [PATCH v7 07/18] unwind_user/deferred: Add unwind_deferred_trace() Steven Rostedt
2025-04-30 19:57 ` [PATCH v7 08/18] unwind_user/deferred: Add unwind cache Steven Rostedt
2025-04-30 19:57 ` [PATCH v7 09/18] perf: Remove get_perf_callchain() init_nr argument Steven Rostedt
2025-04-30 19:57 ` [PATCH v7 10/18] perf: Have get_perf_callchain() return NULL if crosstask and user are set Steven Rostedt
2025-04-30 19:57 ` [PATCH v7 11/18] perf: Use current->flags & PF_KTHREAD instead of current->mm == NULL Steven Rostedt
2025-04-30 19:57 ` Steven Rostedt [this message]
2025-04-30 19:57 ` [PATCH v7 13/18] perf: Skip user unwind if the task is a kernel thread Steven Rostedt
2025-04-30 19:58 ` [PATCH v7 14/18] perf: Support deferred user callchains Steven Rostedt
2025-04-30 19:58 ` [PATCH v7 15/18] perf tools: Minimal CALLCHAIN_DEFERRED support Steven Rostedt
2025-04-30 19:58 ` [PATCH v7 16/18] perf record: Enable defer_callchain for user callchains Steven Rostedt
2025-04-30 19:58 ` [PATCH v7 17/18] perf script: Display PERF_RECORD_CALLCHAIN_DEFERRED Steven Rostedt
2025-04-30 19:58 ` [PATCH v7 18/18] perf tools: Merge deferred user callchains Steven Rostedt
2025-04-30 20:07 ` Ian Rogers
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