From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id B19F2E81A3C for ; Mon, 16 Feb 2026 16:03:55 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id E6DCE6B0088; Mon, 16 Feb 2026 11:03:54 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id E4F046B0089; Mon, 16 Feb 2026 11:03:54 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id D51FD6B008A; Mon, 16 Feb 2026 11:03:54 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id BF3BE6B0088 for ; Mon, 16 Feb 2026 11:03:54 -0500 (EST) Received: from smtpin17.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay10.hostedemail.com (Postfix) with ESMTP id 52EC3C404D for ; Mon, 16 Feb 2026 16:03:54 +0000 (UTC) X-FDA: 84450790788.17.A15D2AF Received: from out-189.mta0.migadu.com (out-189.mta0.migadu.com [91.218.175.189]) by imf12.hostedemail.com (Postfix) with ESMTP id 5419440009 for ; Mon, 16 Feb 2026 16:03:52 +0000 (UTC) Authentication-Results: imf12.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=cww3fojq; spf=pass (imf12.hostedemail.com: domain of usama.arif@linux.dev designates 91.218.175.189 as permitted sender) smtp.mailfrom=usama.arif@linux.dev; dmarc=pass (policy=none) header.from=linux.dev ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1771257832; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=LoBTiJLuQJ9fkPhkSercyUgUATiDuyc3IG1+yyGn5p0=; b=NzKj+qa9wZttba9IHqb5KGDj3yqDV7H6+KqjqNbkXjr1tQRE7mcwj9r8TGwT0hFROwKRXG +8BPIL9HBi1hcH3aozzjoPUsoqoKi17d7OjngjI/wDfVAajEZt43aws2m7YvEqpmAQdsUx vrx2ibQR02O+DQxXX7cYIzXXSB6WrzU= ARC-Authentication-Results: i=1; imf12.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=cww3fojq; spf=pass (imf12.hostedemail.com: domain of usama.arif@linux.dev designates 91.218.175.189 as permitted sender) smtp.mailfrom=usama.arif@linux.dev; dmarc=pass (policy=none) header.from=linux.dev ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1771257832; a=rsa-sha256; cv=none; b=tASV+vI/R2l2DXDJQwuGaZAQQqh1A1Cq399hI88qNtX2VC7d1RakkA1SJaUkhyT6HAXjUZ HpryZYUPYN7oWl00zD6JjWZGURRoXe9L0T50VG2iLEy4UZ0E5L63jIL9Z3pIG296NA2Fa9 38Xd0qPgOfBhNMwL4zxT2t52C/+ZM64= X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1771257830; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=LoBTiJLuQJ9fkPhkSercyUgUATiDuyc3IG1+yyGn5p0=; b=cww3fojq6AJxpft6Q4NoMLB9alkb2FcIGHFdMU9na1WLoNdoeGtMGycT6hDbp3v0U6s/BU V+HJN/izShNhsrA8tGR5/g9WbqtjFwR/SBd3SkJ1uT6IxSOrou9R4aff6Krchincb5x33b RXVB2I3jlAuqLQ6i3h3D3FNdJ6fnFe0= From: Usama Arif To: Thomas Ballasi Cc: Usama Arif , akpm@linux-foundation.org, axelrasmussen@google.com, david@kernel.org, hannes@cmpxchg.org, linux-mm@kvack.org, linux-trace-kernel@vger.kernel.org, lorenzo.stoakes@oracle.com, mhiramat@kernel.org, mhocko@kernel.org, rostedt@goodmis.org, shakeel.butt@linux.dev, weixugc@google.com, yuanchu@google.com, zhengqi.arch@bytedance.com Subject: Re: [PATCH v6 3/3] mm: vmscan: add PIDs to vmscan tracepoints Date: Mon, 16 Feb 2026 08:02:37 -0800 Message-ID: <20260216160247.3956707-1-usama.arif@linux.dev> In-Reply-To: <20260213181537.54350-4-tballasi@linux.microsoft.com> References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT X-Stat-Signature: 1r7kkomsgkdpqz993txczwq6yfx44f6f X-Rspamd-Queue-Id: 5419440009 X-Rspam-User: X-Rspamd-Server: rspam04 X-HE-Tag: 1771257832-459787 X-HE-Meta: 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 BJMXrMbn lmAgN3L0aVNhCcdcVpUTxuq7vYIzNXoB93KzOQtiHVyM+dw4kemAZfNT59Vt5GejOgTyVuzBEtjvkhVzPVUb8jRiqzH09Mg+CveaDHTMfNEa47a9AqFDxZTNiofAwEI/IzpkK617QWNzDY3s2dN2VpD2Qh3M5F/Oa4TQY7AgJoBJfixbi/e7ZGpbHYZRlHVkyfl5XkwmOH07K1EZLwVtygwuXp1d/Edr23J7m X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Fri, 13 Feb 2026 10:15:37 -0800 Thomas Ballasi wrote: > The changes aims at adding additionnal tracepoints variables to help > debuggers attribute them to specific processes. > > The PID field uses in_task() to reliably detect when we're in process > context and can safely access current->pid. When not in process > context (such as in interrupt or in an asynchronous RCU context), the > field is set to -1 as a sentinel value. > > Signed-off-by: Thomas Ballasi > --- > include/trace/events/vmscan.h | 35 +++++++++++++++++++++++++---------- > 1 file changed, 25 insertions(+), 10 deletions(-) > > diff --git a/include/trace/events/vmscan.h b/include/trace/events/vmscan.h > index 1212f6a7c223e..a68b712ef757a 100644 > --- a/include/trace/events/vmscan.h > +++ b/include/trace/events/vmscan.h > @@ -122,18 +122,22 @@ DECLARE_EVENT_CLASS(mm_vmscan_direct_reclaim_begin_template, > __field( unsigned long, gfp_flags ) > __field( u64, memcg_id ) > __field( int, order ) > + __field( int, pid ) > ), > > TP_fast_assign( > __entry->gfp_flags = (__force unsigned long)gfp_flags; > __entry->order = order; > + __entry->pid = current->pid; > __entry->memcg_id = mem_cgroup_id(memcg); > ), > > - TP_printk("order=%d gfp_flags=%s memcg_id=%llu", > + TP_printk("order=%d gfp_flags=%s pid=%d memcg_id=%llu %s", > __entry->order, > show_gfp_flags(__entry->gfp_flags), > - __entry->memcg_id) > + __entry->pid, > + __entry->memcg_id, > + __event_in_irq() ? "(in-irq)" : "") > ); > > DEFINE_EVENT(mm_vmscan_direct_reclaim_begin_template, mm_vmscan_direct_reclaim_begin, > @@ -168,16 +172,20 @@ DECLARE_EVENT_CLASS(mm_vmscan_direct_reclaim_end_template, > TP_STRUCT__entry( > __field( unsigned long, nr_reclaimed ) > __field( u64, memcg_id ) > + __field( int, pid ) > ), > > TP_fast_assign( > __entry->nr_reclaimed = nr_reclaimed; > __entry->memcg_id = mem_cgroup_id(memcg); > + __entry->pid = current->pid; > ), > > - TP_printk("nr_reclaimed=%lu memcg_id=%llu", > + TP_printk("nr_reclaimed=%lu pid=%d memcg_id=%llu %s", > __entry->nr_reclaimed, > - __entry->memcg_id) > + __entry->pid, > + __entry->memcg_id, > + __event_in_irq() ? "(in-irq)" : "") > ); > > DEFINE_EVENT(mm_vmscan_direct_reclaim_end_template, mm_vmscan_direct_reclaim_end, > @@ -220,9 +228,10 @@ TRACE_EVENT(mm_shrink_slab_start, > __field(unsigned long, cache_items) > __field(unsigned long long, delta) > __field(unsigned long, total_scan) > + __field(u64, memcg_id) > __field(int, priority) > __field(int, nid) > - __field(u64, memcg_id) > + __field(int, pid) > ), > > TP_fast_assign( > @@ -236,19 +245,22 @@ TRACE_EVENT(mm_shrink_slab_start, > __entry->priority = priority; > __entry->nid = sc->nid; > __entry->memcg_id = mem_cgroup_id(memcg); > + __entry->pid = current->pid; > ), > > - TP_printk("%pS %p: nid: %d memcg_id: %llu objects to shrink %ld gfp_flags %s cache items %ld delta %lld total_scan %ld priority %d", > + TP_printk("%pS %p: nid: %d pid: %d memcg_id: %llu objects to shrink %ld gfp_flags %s cache items %ld delta %lld total_scan %ld priority %d %s", > __entry->shrink, > __entry->shr, > __entry->nid, > + __entry->pid, > __entry->memcg_id, > __entry->nr_objects_to_shrink, > show_gfp_flags(__entry->gfp_flags), > __entry->cache_items, > __entry->delta, > __entry->total_scan, > - __entry->priority) > + __entry->priority, > + __event_in_irq() ? "(in-irq)" : "") > ); > > TRACE_EVENT(mm_shrink_slab_end, > @@ -266,29 +278,32 @@ TRACE_EVENT(mm_shrink_slab_end, > __field(long, total_scan) > __field(int, nid) > __field(int, retval) > + __field(int, pid) > __field(u64, memcg_id) > ), > > TP_fast_assign( > __entry->shr = shr; > - __entry->shrink = shr->scan_objects; __entry->shrink is removed here, but still printed below. Was this an intended change of this commit? > __entry->unused_scan = unused_scan_cnt; > __entry->new_scan = new_scan_cnt; > __entry->total_scan = total_scan; > __entry->nid = nid; > __entry->retval = shrinker_retval; > + __entry->pid = current->pid; > __entry->memcg_id = mem_cgroup_id(memcg); > ), > > - TP_printk("%pS %p: nid: %d memcg_id: %llu unused scan count %ld new scan count %ld total_scan %ld last shrinker return val %d", > + TP_printk("%pS %p: nid: %d pid: %d memcg_id: %llu unused scan count %ld new scan count %ld total_scan %ld last shrinker return val %d %s", > __entry->shrink, > __entry->shr, > __entry->nid, > + __entry->pid, > __entry->memcg_id, > __entry->unused_scan, > __entry->new_scan, > __entry->total_scan, > - __entry->retval) > + __entry->retval, > + __event_in_irq() ? "(in-irq)" : "") > ); > > TRACE_EVENT(mm_vmscan_lru_isolate, > -- > 2.33.8 > >