From nobody Tue Oct 7 21:50:09 2025 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 CCDEA241103; Fri, 9 May 2025 16:51:40 +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=1746809500; cv=none; b=I/73WHFpa6yO0s9hKR22zGH1ISqisJFk2lr+rQRUicOV6X+pKQAEPjcCLqdTzUDo/AdrfLCYbhxs0dhopt1TXTCEHDjXFL3iA4jdZITHp48h/XQpHZk2Hz7rh6O3mW+cCAORrs8nSEGmTyd07n8g3xrt4gFsfrFaWpqzOeGdEDY= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746809500; c=relaxed/simple; bh=nvl7Vl/7xOcHc3Bu1gQteWzmxNk+BT5GUaar6P8imWE=; h=Message-ID:Date:From:To:Cc:Subject:References:MIME-Version: Content-Type; b=JvFVUESRwbNB3icmXdvnMd6pVnI+/U8HLZDNOQenldb4dY9985ptKjpdtQtqsr02AO4hhoQsmYy6NP21KJ9bUlnQVEQm9SHC5IfXkGNJ2axLbLbr2in7VZCwjVC++u5ey+4H00IxAuBwYm7wmlP9FRAn+DIh+baLTVVXFt3JZLE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5BFABC4CEF3; Fri, 9 May 2025 16:51:40 +0000 (UTC) Received: from rostedt by gandalf with local (Exim 4.98.2) (envelope-from ) id 1uDQx2-00000002gKD-0Tkj; Fri, 09 May 2025 12:51:56 -0400 Message-ID: <20250509165155.965084136@goodmis.org> User-Agent: quilt/0.68 Date: Fri, 09 May 2025 12:45:38 -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 , Namhyung Kim Subject: [PATCH v8 14/18] perf: Remove get_perf_callchain() init_nr argument References: <20250509164524.448387100@goodmis.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable 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 Signed-off-by: Josh Poimboeuf Signed-off-by: Steven Rostedt (Google) Acked-by: Alexei Starovoitov --- 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 947ad12dfdbe..3cc0b0ea0afa 100644 --- a/include/linux/perf_event.h +++ b/include/linux/perf_event.h @@ -1651,7 +1651,7 @@ DECLARE_PER_CPU(struct perf_callchain_entry, perf_cal= lchain_entry); extern void perf_callchain_user(struct perf_callchain_entry_ctx *entry, st= ruct 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 us= er, +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, str= uct bpf_map *, map, if (max_depth > sysctl_perf_event_max_stack) max_depth =3D sysctl_perf_event_max_stack; =20 - trace =3D get_perf_callchain(regs, 0, kernel, user, max_depth, + trace =3D get_perf_callchain(regs, kernel, user, max_depth, false, false); =20 if (unlikely(!trace)) @@ -451,7 +451,7 @@ static long __bpf_get_stack(struct pt_regs *regs, struc= t task_struct *task, else if (kernel && task) trace =3D get_callchain_entry_for_task(task, max_depth); else - trace =3D get_perf_callchain(regs, 0, kernel, user, max_depth, + trace =3D get_perf_callchain(regs, kernel, user, max_depth, crosstask, false); =20 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 p= erf_callchain_entry *entr } =20 struct perf_callchain_entry * -get_perf_callchain(struct pt_regs *regs, u32 init_nr, bool kernel, bool us= er, +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; =20 - ctx.entry =3D entry; - ctx.max_stack =3D max_stack; - ctx.nr =3D entry->nr =3D init_nr; - ctx.contexts =3D 0; - ctx.contexts_maxed =3D false; + ctx.entry =3D entry; + ctx.max_stack =3D max_stack; + ctx.nr =3D entry->nr =3D 0; + ctx.contexts =3D 0; + ctx.contexts_maxed =3D false; =20 if (kernel && !user_mode(regs)) { if (add_mark) diff --git a/kernel/events/core.c b/kernel/events/core.c index 05136e835042..0bac8cae08a8 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -8110,7 +8110,7 @@ perf_callchain(struct perf_event *event, struct pt_re= gs *regs) if (!kernel && !user) return &__empty_callchain; =20 - callchain =3D get_perf_callchain(regs, 0, kernel, user, + callchain =3D get_perf_callchain(regs, kernel, user, max_stack, crosstask, true); return callchain ?: &__empty_callchain; } --=20 2.47.2