From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3C0F9290F; Tue, 8 Jul 2025 02:00:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751940050; cv=none; b=CbNtskR624BpEOjZfcRoIiguYl8ers6YHYN/3g8g1sYkLT3NeuqCQ7EU9wQIWpnKdqMtabjqbEdqUWWDT9fStiXTzzBXbV6GT9ankDCpYi1EFs8wJgHurJKG1mJcqDLLVOF4i0Axc5gauO+73loMgCDA94ADnUUkmGqDdb9AgOg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751940050; c=relaxed/simple; bh=PlMed3FiOV4T6l6o16L8MmIemjqgKth6Lso3Lz/CSCM=; h=Message-ID:Date:From:To:Cc:Subject:References:MIME-Version: Content-Type; b=FdGQyvx7RnTiFVaRdJTo2hO2OLP2D0Ew7ChAXcIPBYvKl7w+k+4lvCwqAB7GsmaqcqXrl+FMA4Tb4y+Zrx1Kyvy/5JE8wYXD8DjmZc3oWRHonCnzOalhjo13jbtvbWOrBX0L4jgILGp4rsVui9KDdnnnjChe48v91wcAadTYNUY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=bm62l0JN; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="bm62l0JN" Received: by smtp.kernel.org (Postfix) with ESMTPSA id F2234C4CEF5; Tue, 8 Jul 2025 02:00:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1751940050; bh=PlMed3FiOV4T6l6o16L8MmIemjqgKth6Lso3Lz/CSCM=; h=Date:From:To:Cc:Subject:References:From; b=bm62l0JNiGZo5Hmr1FcNM47wFa3tdohoktnEuZSBzzWlyB7E5qDrYbyZClKjIVYv7 mySfsK/WMJ40uce1Qtt8nXYgZrpKv7ZBsm/tFDA1wnuGamcO4ltxdvgzhTK4geghQZ rY/kOH1d5yzwfnKSdMa7t4Il3I7Xjy5OL/rf5YRE5DcZGHvg5xcFXzK3d5yaS0V5PM pnoGZKmMgoo8Cs5fYeWs6rIevqYQkF3RXGUCMNDAaq7fCoCzwcq32aqCDLzyT9RtOn Bnokvpktn/dEvfIv5spHZXFRIRVbacAzUKwOjtLi+4AxftS4cpc/R/QJtPO3bEOhVi frPLAvdOhRnEg== Received: from rostedt by gandalf with local (Exim 4.98.2) (envelope-from ) id 1uYxda-00000000D4A-0wDQ; Mon, 07 Jul 2025 22:00:50 -0400 Message-ID: <20250708020050.074392259@kernel.org> User-Agent: quilt/0.68 Date: Mon, 07 Jul 2025 22:00:04 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, bpf@vger.kernel.org, x86@kernel.org Cc: Masami Hiramatsu , Mathieu Desnoyers , Josh Poimboeuf , Peter Zijlstra , Ingo Molnar , Jiri Olsa , Namhyung Kim , Thomas Gleixner , Andrii Nakryiko , Indu Bhagat , "Jose E. Marchesi" , Beau Belgrave , Jens Remus , Linus Torvalds , Andrew Morton , Jens Axboe , Florian Weimer , Sam James , Namhyung Kim , Alexei Starovoitov Subject: [PATCH v13 01/11] perf: Remove get_perf_callchain() init_nr argument References: <20250708020003.565862284@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 From: Josh Poimboeuf The 'init_nr' argument has double duty: it's used to initialize both the number of contexts and the number of stack entries. That's confusing and the callers always pass zero anyway. Hard code the zero. Acked-by: Namhyung Kim Acked-by: Alexei Starovoitov Signed-off-by: Josh Poimboeuf Signed-off-by: Steven Rostedt (Google) --- include/linux/perf_event.h | 2 +- kernel/bpf/stackmap.c | 4 ++-- kernel/events/callchain.c | 12 ++++++------ kernel/events/core.c | 2 +- 4 files changed, 10 insertions(+), 10 deletions(-) diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h index ec9d96025683..54e0d31afcad 100644 --- a/include/linux/perf_event.h +++ b/include/linux/perf_event.h @@ -1719,7 +1719,7 @@ DECLARE_PER_CPU(struct perf_callchain_entry, perf_callchain_entry); extern void perf_callchain_user(struct perf_callchain_entry_ctx *entry, struct pt_regs *regs); extern void perf_callchain_kernel(struct perf_callchain_entry_ctx *entry, struct pt_regs *regs); extern struct perf_callchain_entry * -get_perf_callchain(struct pt_regs *regs, u32 init_nr, bool kernel, bool user, +get_perf_callchain(struct pt_regs *regs, bool kernel, bool user, u32 max_stack, bool crosstask, bool add_mark); extern int get_callchain_buffers(int max_stack); extern void put_callchain_buffers(void); diff --git a/kernel/bpf/stackmap.c b/kernel/bpf/stackmap.c index 3615c06b7dfa..ec3a57a5fba1 100644 --- a/kernel/bpf/stackmap.c +++ b/kernel/bpf/stackmap.c @@ -314,7 +314,7 @@ BPF_CALL_3(bpf_get_stackid, struct pt_regs *, regs, struct bpf_map *, map, if (max_depth > sysctl_perf_event_max_stack) max_depth = sysctl_perf_event_max_stack; - trace = get_perf_callchain(regs, 0, kernel, user, max_depth, + trace = get_perf_callchain(regs, kernel, user, max_depth, false, false); if (unlikely(!trace)) @@ -451,7 +451,7 @@ static long __bpf_get_stack(struct pt_regs *regs, struct task_struct *task, else if (kernel && task) trace = get_callchain_entry_for_task(task, max_depth); else - trace = get_perf_callchain(regs, 0, kernel, user, max_depth, + trace = get_perf_callchain(regs, kernel, user, max_depth, crosstask, false); if (unlikely(!trace) || trace->nr < skip) { diff --git a/kernel/events/callchain.c b/kernel/events/callchain.c index 6c83ad674d01..b0f5bd228cd8 100644 --- a/kernel/events/callchain.c +++ b/kernel/events/callchain.c @@ -217,7 +217,7 @@ static void fixup_uretprobe_trampoline_entries(struct perf_callchain_entry *entr } struct perf_callchain_entry * -get_perf_callchain(struct pt_regs *regs, u32 init_nr, bool kernel, bool user, +get_perf_callchain(struct pt_regs *regs, bool kernel, bool user, u32 max_stack, bool crosstask, bool add_mark) { struct perf_callchain_entry *entry; @@ -228,11 +228,11 @@ get_perf_callchain(struct pt_regs *regs, u32 init_nr, bool kernel, bool user, if (!entry) return NULL; - ctx.entry = entry; - ctx.max_stack = max_stack; - ctx.nr = entry->nr = init_nr; - ctx.contexts = 0; - ctx.contexts_maxed = false; + ctx.entry = entry; + ctx.max_stack = max_stack; + ctx.nr = entry->nr = 0; + ctx.contexts = 0; + ctx.contexts_maxed = false; if (kernel && !user_mode(regs)) { if (add_mark) diff --git a/kernel/events/core.c b/kernel/events/core.c index 0db36b2b2448..b2a53cabcb17 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -8178,7 +8178,7 @@ perf_callchain(struct perf_event *event, struct pt_regs *regs) if (!kernel && !user) return &__empty_callchain; - callchain = get_perf_callchain(regs, 0, kernel, user, + callchain = get_perf_callchain(regs, kernel, user, max_stack, crosstask, true); return callchain ?: &__empty_callchain; } -- 2.47.2