From nobody Thu Apr 9 12:54:34 2026 Received: from m16.mail.126.com (m16.mail.126.com [220.197.31.7]) (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 EB92E258EFF; Mon, 9 Mar 2026 02:30:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=220.197.31.7 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773023409; cv=none; b=IvBCjZVEFU1MiV3W6DIXhRY6U6T1+0Tz43nvBMMRF8da+GMVz5ow5oCdFi7LksL61iPsw7UdKd5wqOPJQ4QScZ4oWMsE7j9mHftBud6gzp6hYFpoSWB+0XS+cVQK0xeQJblKL8+X/D63Jps8B0+MdgmRX1M6X+fHvduj5yY4cTI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773023409; c=relaxed/simple; bh=PytrpEKu4z4cSniLZJgATP9QtiYJe2vxD7ljF7M4rvo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=nr5arGbN9/By6Bw16fbIoNTnhKtwPY+UsgyCnoWtpBa+80cssjbEKbO5siEFN4nQKmVoRsugSRlW8ey8G/YS75w1DnrvupYKrup9i2Pz66ztQJlNsiM9oOQS9K5yNOaSM6NM7CLrQ8gCFVJKpCc9xPJECdrH5Mwx73vChPE9TOE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=126.com; spf=pass smtp.mailfrom=126.com; dkim=pass (1024-bit key) header.d=126.com header.i=@126.com header.b=Udj3BQVI; arc=none smtp.client-ip=220.197.31.7 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=126.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=126.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=126.com header.i=@126.com header.b="Udj3BQVI" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=126.com; s=s110527; h=From:To:Subject:Date:Message-ID:MIME-Version; bh=XB EAi+d0EcrM28oc+704+b++RsibF9o45FVGfBaavnk=; b=Udj3BQVIRFTcv4ceir AEAtx+1hMGiwSFy1hQeZH2ytKuw7gAghKSYpvPVz6+6UTbPw2+1mUOFMikmz/rC4 CrM/4U1Lpcb4jNtCaKi/BR2NHHGAGuLpj189PbFZZOw1ifcwTIWANcCznshByprq /lDZG8LaSBh87tipEpZSj4SP0= Received: from localhost.localdomain (unknown []) by gzsmtp1 (Coremail) with SMTP id PCkvCgDHb_5qMK5pKd7+BA--.65315S3; Mon, 09 Mar 2026 10:28:59 +0800 (CST) From: Zhao Mengmeng To: tj@kernel.org, void@manifault.com, arighi@nvidia.com, changwoo@igalia.com, nathan@kernel.org, nick.desaulniers+lkml@gmail.com, morbo@google.com, justinstitt@google.com, emil@etsalapatis.com Cc: sched-ext@lists.linux.dev, linux-kernel@vger.kernel.org, bpf@vger.kernel.org, llvm@lists.linux.dev, zhaomengmeng@kylinos.cn Subject: [PATCH v2 1/2] sched_ext: remove SCX_OPS_HAS_CGROUP_WEIGHT Date: Mon, 9 Mar 2026 10:28:46 +0800 Message-ID: <20260309022847.106150-2-zhaomzhao@126.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260309022847.106150-1-zhaomzhao@126.com> References: <20260309022847.106150-1-zhaomzhao@126.com> 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 X-CM-TRANSID: PCkvCgDHb_5qMK5pKd7+BA--.65315S3 X-Coremail-Antispam: 1Uf129KBjvJXoWxJw4xZryxCF4rJr4kGF43Awb_yoW5CF1fpa 1DZr48tr12qry7Ga18Ca1kury7Ww43Gw12gr98Xw4S9r4kGw4aqw1Yqr43ArWYqFWrZFZ3 GFWq9a47Kw1jgF7anT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDUYxBIdaVFxhVjvjDU0xZFpf9x07UDrcfUUUUU= X-CM-SenderInfo: 52kd0zp2kd0qqrswhudrp/xtbBqwwtpGmuMGw5owAA3v Content-Type: text/plain; charset="utf-8" From: Zhao Mengmeng While running scx_flatcg, dmesg prints "SCX_OPS_HAS_CGROUP_WEIGHT is deprecated and a noop", in code, SCX_OPS_HAS_CGROUP_WEIGHT has been marked as DEPRECATED, and will be removed on 6.18. Now it's time to do it. Signed-off-by: Zhao Mengmeng --- kernel/sched/ext.c | 3 --- kernel/sched/ext_internal.h | 8 +------- tools/sched_ext/include/scx/enum_defs.autogen.h | 1 - tools/sched_ext/scx_flatcg.bpf.c | 2 +- 4 files changed, 2 insertions(+), 12 deletions(-) diff --git a/kernel/sched/ext.c b/kernel/sched/ext.c index d6d807337013..69bb2e5b1adb 100644 --- a/kernel/sched/ext.c +++ b/kernel/sched/ext.c @@ -6282,9 +6282,6 @@ static int validate_ops(struct scx_sched *sch, const = struct sched_ext_ops *ops) return -EINVAL; } =20 - if (ops->flags & SCX_OPS_HAS_CGROUP_WEIGHT) - pr_warn("SCX_OPS_HAS_CGROUP_WEIGHT is deprecated and a noop\n"); - if (ops->cpu_acquire || ops->cpu_release) pr_warn("ops->cpu_acquire/release() are deprecated, use sched_switch TP = instead\n"); =20 diff --git a/kernel/sched/ext_internal.h b/kernel/sched/ext_internal.h index f8df73044515..bec4d22890b0 100644 --- a/kernel/sched/ext_internal.h +++ b/kernel/sched/ext_internal.h @@ -180,19 +180,13 @@ enum scx_ops_flags { */ SCX_OPS_BUILTIN_IDLE_PER_NODE =3D 1LLU << 6, =20 - /* - * CPU cgroup support flags - */ - SCX_OPS_HAS_CGROUP_WEIGHT =3D 1LLU << 16, /* DEPRECATED, will be removed = on 6.18 */ - SCX_OPS_ALL_FLAGS =3D SCX_OPS_KEEP_BUILTIN_IDLE | SCX_OPS_ENQ_LAST | SCX_OPS_ENQ_EXITING | SCX_OPS_ENQ_MIGRATION_DISABLED | SCX_OPS_ALLOW_QUEUED_WAKEUP | SCX_OPS_SWITCH_PARTIAL | - SCX_OPS_BUILTIN_IDLE_PER_NODE | - SCX_OPS_HAS_CGROUP_WEIGHT, + SCX_OPS_BUILTIN_IDLE_PER_NODE, =20 /* high 8 bits are internal, don't include in SCX_OPS_ALL_FLAGS */ __SCX_OPS_INTERNAL_MASK =3D 0xffLLU << 56, diff --git a/tools/sched_ext/include/scx/enum_defs.autogen.h b/tools/sched_= ext/include/scx/enum_defs.autogen.h index 78d34f0c29f0..40b30dad8ede 100644 --- a/tools/sched_ext/include/scx/enum_defs.autogen.h +++ b/tools/sched_ext/include/scx/enum_defs.autogen.h @@ -114,7 +114,6 @@ #define HAVE_SCX_OPS_ENQ_MIGRATION_DISABLED #define HAVE_SCX_OPS_ALLOW_QUEUED_WAKEUP #define HAVE_SCX_OPS_BUILTIN_IDLE_PER_NODE -#define HAVE_SCX_OPS_HAS_CGROUP_WEIGHT #define HAVE_SCX_OPS_ALL_FLAGS #define HAVE___SCX_OPS_INTERNAL_MASK #define HAVE_SCX_OPS_HAS_CPU_PREEMPT diff --git a/tools/sched_ext/scx_flatcg.bpf.c b/tools/sched_ext/scx_flatcg.= bpf.c index 0e785cff0f24..a8a9234bb41e 100644 --- a/tools/sched_ext/scx_flatcg.bpf.c +++ b/tools/sched_ext/scx_flatcg.bpf.c @@ -960,5 +960,5 @@ SCX_OPS_DEFINE(flatcg_ops, .cgroup_move =3D (void *)fcg_cgroup_move, .init =3D (void *)fcg_init, .exit =3D (void *)fcg_exit, - .flags =3D SCX_OPS_HAS_CGROUP_WEIGHT | SCX_OPS_ENQ_EXITING, + .flags =3D SCX_OPS_ENQ_EXITING, .name =3D "flatcg"); 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Mon, 09 Mar 2026 10:29:00 +0800 (CST) From: Zhao Mengmeng To: tj@kernel.org, void@manifault.com, arighi@nvidia.com, changwoo@igalia.com, nathan@kernel.org, nick.desaulniers+lkml@gmail.com, morbo@google.com, justinstitt@google.com, emil@etsalapatis.com Cc: sched-ext@lists.linux.dev, linux-kernel@vger.kernel.org, bpf@vger.kernel.org, llvm@lists.linux.dev, zhaomengmeng@kylinos.cn Subject: [PATCH v2 2/2] tools/sched_ext: scx_sdt: Fix BPF verifier rejection on older LLVMs Date: Mon, 9 Mar 2026 10:28:47 +0800 Message-ID: <20260309022847.106150-3-zhaomzhao@126.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260309022847.106150-1-zhaomzhao@126.com> References: <20260309022847.106150-1-zhaomzhao@126.com> 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 X-CM-TRANSID: PCkvCgDHb_5qMK5pKd7+BA--.65315S4 X-Coremail-Antispam: 1Uf129KBjvJXoWxKw45WFW7Jw1xXF1UuFyDJrb_yoW7XFW7pF WUJFyDXF1Utrn3Arn7t3ZYyrs3CanrXr1UWayrKrn7Z3sI9wnrX34Ikw1Fvr4qyrWSyay3 ZFZrC3Z2qF15JrJanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDUYxBIdaVFxhVjvjDU0xZFpf9x07jYT5QUUUUU= X-CM-SenderInfo: 52kd0zp2kd0qqrswhudrp/xtbBqwwtpGmuMGw5qwAA3n Content-Type: text/plain; charset="utf-8" From: Zhao Mengmeng Under Clang 17/18, when running scx_sdt scheduler, it fails with: libbpf: prog 'sdt_init_task': BPF program load failed: -EACCES libbpf: prog 'sdt_init_task': -- BEGIN PROG LOAD LOG -- ... ; desc =3D desc_find_empty(alloc->root, &idx); @ scx_sdt.bpf.c:479 43: (79) r8 =3D *(u64 *)(r6 +32) ; frame1: R6=3Dmap_value(map=3Dscx_= sdt.bss,ks=3D4,vs=3D200,off=3D120) R8=3Dscalar() ; for (level =3D zero; level < SDT_TASK_LEVELS && can_loop; level++) { @ sc= x_sdt.bpf.c:407 44: (e5) may_goto pc+51 ; idx |=3D pos; @ scx_sdt.bpf.c:418 96: (bf) r7 =3D r2 ; frame1: R2=3D0 R7=3D0 97: (bf) r1 =3D r10 ; frame1: R1=3Dfp0 R10=3Dfp0 ; @ scx_sdt.bpf.c:0 98: (07) r1 +=3D -56 ; frame1: R1=3Dfp-56 ; bpf_for(u, 0, SDT_TASK_LEVELS) { @ scx_sdt.bpf.c:447 99: (b4) w2 =3D 0 ; frame1: R2=3D0 100: (b4) w3 =3D 3 ; frame1: R3=3D3 101: (85) call bpf_iter_num_new#82234 ; frame1: R0=3Dscalar() fp-56= =3Diter_num(ref_id=3D2,state=3Dactive,depth=3D0) 102: (18) r9 =3D 0x1ffffffffffffff8 ; frame1: R9=3D0x1ffffffffffffff8 104: (bf) r1 =3D r10 ; frame1: R1=3Dfp0 R10=3Dfp0 ; @ scx_sdt.bpf.c:0 105: (07) r1 +=3D -56 ; frame1: R1=3Dfp-56 ; bpf_for(u, 0, SDT_TASK_LEVELS) { @ scx_sdt.bpf.c:447 106: (85) call bpf_iter_num_next#82235 ; frame1: R0=3D0 fp-56=3Diter= _num(ref_id=3D2,state=3Ddrained,depth=3D0) 107: (15) if r0 =3D=3D 0x0 goto pc+29 ; frame1: R0=3D0 ; if (tmp->nr_free > 0) @ scx_sdt.bpf.c:456 137: (bf) r1 =3D r10 ; frame1: R1=3Dfp0 R10=3Dfp0 ; bpf_for(u, 0, SDT_TASK_LEVELS) { @ scx_sdt.bpf.c:447 138: (07) r1 +=3D -56 ; frame1: R1=3Dfp-56 139: (85) call bpf_iter_num_destroy#82232 ; frame1: 140: (b7) r9 =3D 0 ; frame1: R9=3D0 ; if (unlikely(desc =3D=3D NULL)) { @ scx_sdt.bpf.c:480 141: (15) if r8 =3D=3D 0x0 goto pc+15 ; frame1: R8=3Dscalar(umin=3D1) ; chunk =3D desc->chunk; @ scx_sdt.bpf.c:485 142: (79) r4 =3D *(u64 *)(r8 +72) R8 invalid mem access 'scalar' The reason is these older compilers lacks native support for __BPF_FEATURE_ADDR_SPACE_CAST, __arena macro is defined as empty. Fix it by adding cast_kern when dereferencing variables with __arena tag. Signed-off-by: Zhao Mengmeng --- tools/sched_ext/scx_sdt.bpf.c | 20 +++++++++++++++++++- 1 file changed, 19 insertions(+), 1 deletion(-) diff --git a/tools/sched_ext/scx_sdt.bpf.c b/tools/sched_ext/scx_sdt.bpf.c index 31b09958e8d5..caacc55bd7a5 100644 --- a/tools/sched_ext/scx_sdt.bpf.c +++ b/tools/sched_ext/scx_sdt.bpf.c @@ -148,6 +148,7 @@ static sdt_desc_t *scx_alloc_chunk(void) =20 out =3D desc; =20 + cast_kern(desc); desc->nr_free =3D SDT_TASK_ENTS_PER_CHUNK; desc->chunk =3D chunk; =20 @@ -244,6 +245,7 @@ int mark_nodes_avail(sdt_desc_t *lv_desc[SDT_TASK_LEVEL= S], __u64 lv_pos[SDT_TASK /* Only propagate upwards if we are the parent's only free chunk. */ desc =3D lv_desc[level]; =20 + cast_kern(desc); ret =3D set_idx_state(desc, lv_pos[level], false); if (unlikely(ret !=3D 0)) return ret; @@ -298,20 +300,26 @@ int scx_alloc_free_idx(struct scx_allocator *alloc, _= _u64 idx) if (level =3D=3D SDT_TASK_LEVELS - 1) break; =20 + cast_kern(desc); chunk =3D desc->chunk; =20 + cast_kern(chunk); desc_children =3D (sdt_desc_t * __arena *)chunk->descs; + cast_kern(desc_children); desc =3D desc_children[pos]; =20 if (unlikely(!desc)) return -EINVAL; } =20 + cast_kern(desc); chunk =3D desc->chunk; =20 pos =3D idx & mask; + cast_kern(chunk); data =3D chunk->data[pos]; if (likely(data)) { + cast_kern(data); *data =3D (struct sdt_data) { .tid.genn =3D data->tid.genn + 1, }; @@ -378,6 +386,7 @@ __u64 chunk_find_empty(sdt_desc_t __arg_arena *desc) __u64 freeslots; __u64 i; =20 + cast_kern(desc); for (i =3D 0; i < SDT_TASK_CHUNK_BITMAP_U64S; i++) { freeslots =3D ~desc->allocated[i]; if (freeslots =3D=3D (__u64)0) @@ -426,9 +435,12 @@ static sdt_desc_t * desc_find_empty(sdt_desc_t *desc, = __u64 *idxp) break; =20 /* Allocate an internal node if necessary. */ + cast_kern(desc); chunk =3D desc->chunk; + cast_kern(chunk); desc_children =3D (sdt_desc_t * __arena *)chunk->descs; =20 + cast_kern(desc_children); desc =3D desc_children[pos]; if (!desc) { desc =3D scx_alloc_chunk(); @@ -448,6 +460,7 @@ static sdt_desc_t * desc_find_empty(sdt_desc_t *desc, _= _u64 *idxp) level =3D SDT_TASK_LEVELS - 1 - u; tmp =3D lv_desc[level]; =20 + cast_kern(tmp); ret =3D set_idx_state(tmp, lv_pos[level], true); if (ret !=3D 0) break; @@ -482,10 +495,12 @@ void __arena *scx_alloc(struct scx_allocator *alloc) return NULL; } =20 + cast_kern(desc); chunk =3D desc->chunk; =20 /* Populate the leaf node if necessary. */ pos =3D idx & (SDT_TASK_ENTS_PER_CHUNK - 1); + cast_kern(chunk); data =3D chunk->data[pos]; if (!data) { data =3D scx_alloc_from_pool(&alloc->pool); @@ -503,10 +518,12 @@ void __arena *scx_alloc(struct scx_allocator *alloc) alloc_stats.alloc_ops +=3D 1; alloc_stats.active_allocs +=3D 1; =20 + cast_kern(data); data->tid.idx =3D idx; =20 bpf_spin_unlock(&alloc_lock); =20 + cast_user(data); return data; } =20 @@ -544,9 +561,10 @@ void __arena *scx_task_alloc(struct task_struct *p) if (unlikely(!data)) return NULL; =20 + mval->data =3D data; + cast_kern(data); mval->tid =3D data->tid; mval->tptr =3D (__u64) p; - mval->data =3D data; =20 return (void __arena *)data->payload; } --=20 2.43.0