From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=91.218.175.46 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793205450; b=BxayibV3w7VXxivXRFp9nT8LsjuIcj2g35Xxt0tf7ooCVaYl4fU8D1C3G7H31vMU8kdY FPyg4y32SJ6wt7SwUHAZHfy1ESnZVqfmicDPNqeN5BVdCNNivyE7i3wJX4i8zo99dDE05 hj6nw1zkKWsPVRi/oaSxFy4t7LQOKq6gws7mUlHmhjPXQW9hXop+8GWiVsknsXRSaLcES XlfCs8JWz6v/6/2XdZP/SJw/xgQN35riwU9sayJ3XnPwiTzq6vYcHYDZ5ggeuefcu8LEc P0DKgog5AVSmCGl6K52vSFOA6H9X9WUn/rxowQD7TxVvOIveXkm2jWuZXGdn81H303A== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793205450; h=DMARC-Filter:X-Envelope-To:DKIM-Signature:X-Envelope-To:Received: X-Mizu-Trace-ID:X-Migadu-Flow:From:To:Cc:Subject:Date:Message-Id: X-Mailer:In-Reply-To:References:MIME-Version: Content-Transfer-Encoding; bh=c0QuGi9vebWt/TMI1t8TdElZu+dctmkfByTpUVeybjc=; b=fE7TmnENX2sq9qK8DjogGjdPU0jXH8k+O3U75gULfCc6jldqJ42qlMbuzz3lG2A+rGxc lq1CWc3yyqYFrjxi4rrA0oc+3YWFdlWRuP9fKQa7r8d2md9FJFbm0YGNzeHxLbE5oALUZ 17SDYSp9DXXEN37whS8PSw5KQBZHX6Ge5JfdrVB3LeBkqhK5KtSJj/ZpPKlRcA+qF+3+E tT4HG6ijyXb8FTtoipr2/JJzksu19jplVmmlwlMs5A5uHW/rcVh1uYYn0fePKLAAnf038 s38IowVr/Rn/MTwOTr4IdSBbEeDERoXvpfs67fudFeTaQ3q6aQEy08hTolhzXjEzZRQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass header.d=linux.dev header.i=@linux.dev header.a=rsa-sha256 header.s=key1 header.b=gxofaJx9; arc=none smtp.remote-ip=91.218.175.46 Received: from mta0.migadu.com (out-46.mta0.migadu.com [91.218.175.46]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id F11B060A3829 for ; Wed, 28 Oct 2026 16:37:28 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org F11B060A3829 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linux.dev header.i=@linux.dev header.a=rsa-sha256 header.s=key1 header.b=gxofaJx9 X-Envelope-To: linux-kernel@vger.kernel.org DKIM-Signature: a=rsa-sha256; bh=UV9Dwqu1DdDd296qahuFF7A+j1SKw/YhONwnecnFrcA=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1793205447; v=1; x=1793810247; b=gxofaJx9tQaIlEqxXQb1Dxri0iTEW0tagi8mrUUOPz67a8f9ed9TpSOVAeWrygkFYGAMZAxQ d1G2TvxrUJ4PUaxdZQ061VVm3+j8cmlDUAdEHs8tvspLBiynDVhYjmHmMHrXsTThVUccbo265ju H2SXBEFS+6PaUqdcH6vFz2so= X-Envelope-To: linux-kernel@vger.kernel.org Received: by mta11.migadu.com with ESMTPS id 4c812e0bccd7e663; Wed, 28 Oct 2026 16:37:27 +0000 X-Mizu-Trace-ID: 4c812e0bccd7e663 X-Migadu-Flow: FLOW_OUT From: wen.yang@linux.dev To: Joel Granados Cc: Wen Yang , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [RFC PATCH 20/39] sysctl: refresh dynamic scheduler and PID bounds per call Date: Thu, 29 Oct 2026 00:34:59 +0800 Message-Id: <380ffe2d74c23b66e419511af4f25d5268a46ed4.1793204511.git.wen.yang@linux.dev> X-Mailer: git-send-email 2.25.1 In-Reply-To: References: X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Wen Yang Read current scheduler and PID limits into local tables before validation. Suggested-by: Joel Granados Signed-off-by: Wen Yang --- kernel/fork.c | 8 ++++---- kernel/pid.c | 16 +++++++++++++--- kernel/pid_namespace.c | 6 +++--- kernel/pid_sysctl.h | 6 +++--- kernel/sched/deadline.c | 29 +++++++++++++++++++++++++---- kernel/sched/rt.c | 13 ++++++++----- 6 files changed, 56 insertions(+), 22 deletions(-) diff --git a/kernel/fork.c b/kernel/fork.c index 18b6dd851642..44947ef38cb4 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -3364,13 +3364,11 @@ static int sysctl_max_threads(const struct ctl_table *table, int write, struct ctl_table t; int ret; int threads = max_threads; - int min = 1; - int max = MAX_THREADS; t = *table; t.data = &threads; - t.extra1 = &min; - t.extra2 = &max; + t.min = 1; + t.max = MAX_THREADS; ret = proc_dointvec_minmax(&t, write, buffer, lenp, ppos); if (ret || !write) @@ -3388,6 +3386,8 @@ static const struct ctl_table fork_sysctl_table[] = { .maxlen = sizeof(int), .mode = 0644, .proc_handler = sysctl_max_threads, + .min = 1, + .max = MAX_THREADS, }, }; diff --git a/kernel/pid.c b/kernel/pid.c index adf721606768..21ffdc3d4ea7 100644 --- a/kernel/pid.c +++ b/kernel/pid.c @@ -766,15 +766,25 @@ static struct ctl_table_root pid_table_root = { .set_ownership = pid_table_root_set_ownership, }; +static int pid_max_handler(const struct ctl_table *table, int write, + void *buffer, size_t *lenp, loff_t *ppos) +{ + struct ctl_table tmp = *table; + + tmp.min = (unsigned long)READ_ONCE(pid_max_min); + tmp.max = (unsigned long)READ_ONCE(pid_max_max); + return proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos); +} + static const struct ctl_table pid_table[] = { { .procname = "pid_max", .data = &init_pid_ns.pid_max, .maxlen = sizeof(int), .mode = 0644, - .proc_handler = proc_dointvec_minmax, - .extra1 = &pid_max_min, - .extra2 = &pid_max_max, + .proc_handler = pid_max_handler, + .min = (unsigned long)INT_MIN, + .max = INT_MAX, }, }; #endif diff --git a/kernel/pid_namespace.c b/kernel/pid_namespace.c index 127a5fd23e70..fe173ec63cb2 100644 --- a/kernel/pid_namespace.c +++ b/kernel/pid_namespace.c @@ -297,7 +297,7 @@ static int pid_ns_ctl_handler(const struct ctl_table *table, int write, next = idr_get_cursor(&pid_ns->idr) - 1; tmp.data = &next; - tmp.extra2 = &pid_ns->pid_max; + tmp.max = READ_ONCE(pid_ns->pid_max); ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos); if (!ret && write) idr_set_cursor(&pid_ns->idr, next + 1); @@ -311,8 +311,8 @@ static const struct ctl_table pid_ns_ctl_table[] = { .maxlen = sizeof(int), .mode = 0666, /* permissions are checked in the handler */ .proc_handler = pid_ns_ctl_handler, - .extra1 = SYSCTL_ZERO, - .extra2 = &init_pid_ns.pid_max, + .min = 0, + .max = INT_MAX, }, }; #endif /* CONFIG_CHECKPOINT_RESTORE */ diff --git a/kernel/pid_sysctl.h b/kernel/pid_sysctl.h index 5d8f981de7c5..a7b90380285d 100644 --- a/kernel/pid_sysctl.h +++ b/kernel/pid_sysctl.h @@ -23,7 +23,7 @@ static int pid_mfd_noexec_dointvec_minmax(const struct ctl_table *table, scope = max(READ_ONCE(ns->memfd_noexec_scope), parent_scope); table_copy.data = &scope; - table_copy.extra1 = &parent_scope; + table_copy.min = (unsigned long)parent_scope; err = proc_dointvec_minmax(&table_copy, write, buf, lenp, ppos); if (!err && write) @@ -38,8 +38,8 @@ static const struct ctl_table pid_ns_ctl_table_vm[] = { .maxlen = sizeof(init_pid_ns.memfd_noexec_scope), .mode = 0644, .proc_handler = pid_mfd_noexec_dointvec_minmax, - .extra1 = SYSCTL_ZERO, - .extra2 = SYSCTL_TWO, + .min = 0, + .max = 2, }, }; static inline void register_pid_ns_sysctl_table_vm(void) diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c index c0ebdcde5fe5..bf27abdd5c33 100644 --- a/kernel/sched/deadline.c +++ b/kernel/sched/deadline.c @@ -19,6 +19,7 @@ #include #include #include +#include #include #include "sched.h" #include "pelt.h" @@ -31,22 +32,42 @@ static unsigned int sysctl_sched_dl_period_max = 1 << 22; /* ~4 seconds */ static unsigned int sysctl_sched_dl_period_min = 100; /* 100 us */ #ifdef CONFIG_SYSCTL +static int sched_dl_period_max_handler(const struct ctl_table *table, int write, + void *buffer, size_t *lenp, loff_t *ppos) +{ + struct ctl_table tmp = *table; + + tmp.min = READ_ONCE(sysctl_sched_dl_period_min); + return proc_douintvec_minmax(&tmp, write, buffer, lenp, ppos); +} + +static int sched_dl_period_min_handler(const struct ctl_table *table, int write, + void *buffer, size_t *lenp, loff_t *ppos) +{ + struct ctl_table tmp = *table; + + tmp.max = READ_ONCE(sysctl_sched_dl_period_max); + return proc_douintvec_minmax(&tmp, write, buffer, lenp, ppos); +} + static const struct ctl_table sched_dl_sysctls[] = { { .procname = "sched_deadline_period_max_us", .data = &sysctl_sched_dl_period_max, .maxlen = sizeof(unsigned int), .mode = 0644, - .proc_handler = proc_douintvec_minmax, - .extra1 = (void *)&sysctl_sched_dl_period_min, + .proc_handler = sched_dl_period_max_handler, + .min = 0, + .max = UINT_MAX, }, { .procname = "sched_deadline_period_min_us", .data = &sysctl_sched_dl_period_min, .maxlen = sizeof(unsigned int), .mode = 0644, - .proc_handler = proc_douintvec_minmax, - .extra2 = (void *)&sysctl_sched_dl_period_max, + .proc_handler = sched_dl_period_min_handler, + .min = 0, + .max = UINT_MAX, }, }; diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c index 1535046a23ff..26e9b2ac8838 100644 --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -36,8 +36,8 @@ static const struct ctl_table sched_rt_sysctls[] = { .maxlen = sizeof(int), .mode = 0644, .proc_handler = sched_rt_handler, - .extra1 = SYSCTL_ONE, - .extra2 = SYSCTL_INT_MAX, + .min = 1, + .max = INT_MAX, }, { .procname = "sched_rt_runtime_us", @@ -45,8 +45,8 @@ static const struct ctl_table sched_rt_sysctls[] = { .maxlen = sizeof(int), .mode = 0644, .proc_handler = sched_rt_handler, - .extra1 = SYSCTL_NEG_ONE, - .extra2 = (void *)&sysctl_sched_rt_period, + .min = (unsigned long)-1, + .max = INT_MAX, }, { .procname = "sched_rr_timeslice_ms", @@ -2872,6 +2872,7 @@ static int sched_rt_global_validate(void) static int sched_rt_handler(const struct ctl_table *table, int write, void *buffer, size_t *lenp, loff_t *ppos) { + struct ctl_table tmp = *table; int old_period, old_runtime; static DEFINE_MUTEX(mutex); int ret; @@ -2881,7 +2882,9 @@ static int sched_rt_handler(const struct ctl_table *table, int write, void *buff old_period = sysctl_sched_rt_period; old_runtime = sysctl_sched_rt_runtime; - ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); + if (table->data == &sysctl_sched_rt_runtime) + tmp.max = READ_ONCE(sysctl_sched_rt_period); + ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos); if (!ret && write) { ret = sched_rt_global_validate(); -- 2.25.1