From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-179.mta0.migadu.com (out-179.mta0.migadu.com [91.218.175.179]) (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 9547918BBAE for ; Mon, 8 Jun 2026 04:10:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.179 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780891823; cv=none; b=ToofV1Xmkg9D0KNNTcEATBSc2HWyCCJHlT9dfLEPuCP/0xyBaP/1DbM1O+ppXUuoYGkem8zTic7KSOteQmGML9FWFSVGPdm2JdapnnPlVY05cDMs9YqpjUthIzDpyggms9fRfSIJzdHCTveGYjuDDtcVIQuO+yEmJnyQNY8NNc0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780891823; c=relaxed/simple; bh=+esi5+wmEbzr0U6tFH3wrxjSlcekmUCxuh42Y1DjLXU=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=ZsSMDo9SdVsMjGXQ1gxZRBsZrfjwJRRmwMFn9fDDT6msM+G+AIFSpuPTWjaXFtTaNHZe3PyG2jHnUaPzeT/+9KhTtORYTQKaDfbetNtRz9d5VYPOsX/YJb1vqozbjDRGbN4bBnFejYcsr3lIAZJF5cKh1G3xQv+XLIRVXMY3Oto= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=PhJQmJ4C; arc=none smtp.client-ip=91.218.175.179 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) header.d=linux.dev header.i=@linux.dev header.b="PhJQmJ4C" Message-ID: <5d77fadd-13a9-40ed-a8e8-2982ceb69af2@linux.dev> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1780891818; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=RQr+FS5WTq4T7wFBMSLf3go6FakMkvtgbNGjQKWlmw8=; b=PhJQmJ4C/cVE3UbVc5wYGTEjz2tdfRoaX48ehWPeZGWP7Nl/U5dlWYmpKB1nM2j5tvtc1F TO+/1SxF/Rg2fTp6M1SiLweIkGXWaSsWgQCzz3tFTWcWSg8Oqo4qT8Zv9umC7GkENoV4QC MLD6Yv9D6n9IuOrQPo76T96avYRGiaA= Date: Mon, 8 Jun 2026 12:09:37 +0800 Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Subject: Re: [PATCH v3 3/6] alloc_tag: add size-based filtering to ioctl To: Abhishek Bapat , Suren Baghdasaryan , Andrew Morton , Kent Overstreet Cc: Shuah Khan , Jonathan Corbet , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Sourav Panda References: Content-Language: en-US X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Hao Ge In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Migadu-Flow: FLOW_OUT Hi Abhishek Thanks for the new version. On 2026/6/6 07:36, Abhishek Bapat wrote: > Extend the allocinfo filtering mechanism to allow users to filter tags > based on the total number of bytes allocated [min_size, max_size]. The > size range is inclusive. > > Filtering by size involves retrieving allocinfo per-CPU counters, which > is an expensive operation. Hence, the performance of size-based > filtering will be worse than other filters. > > Signed-off-by: Abhishek Bapat > --- > include/uapi/linux/alloc_tag.h | 8 +++- > lib/alloc_tag.c | 68 +++++++++++++++++++++++++++------- > 2 files changed, 62 insertions(+), 14 deletions(-) > > diff --git a/include/uapi/linux/alloc_tag.h b/include/uapi/linux/alloc_tag.h > index cffb0c46e0b1..0e648192df4d 100644 > --- a/include/uapi/linux/alloc_tag.h > +++ b/include/uapi/linux/alloc_tag.h > @@ -39,13 +39,17 @@ enum { > ALLOCINFO_FILTER_FUNCTION, > ALLOCINFO_FILTER_FILENAME, > ALLOCINFO_FILTER_LINENO, > - __ALLOCINFO_FILTER_LAST = ALLOCINFO_FILTER_LINENO > + ALLOCINFO_FILTER_MIN_SIZE, > + ALLOCINFO_FILTER_MAX_SIZE, > + __ALLOCINFO_FILTER_LAST = ALLOCINFO_FILTER_MAX_SIZE > }; > > #define ALLOCINFO_FILTER_MASK_MODNAME (1 << ALLOCINFO_FILTER_MODNAME) > #define ALLOCINFO_FILTER_MASK_FUNCTION (1 << ALLOCINFO_FILTER_FUNCTION) > #define ALLOCINFO_FILTER_MASK_FILENAME (1 << ALLOCINFO_FILTER_FILENAME) > #define ALLOCINFO_FILTER_MASK_LINENO (1 << ALLOCINFO_FILTER_LINENO) > +#define ALLOCINFO_FILTER_MASK_MIN_SIZE (1 << ALLOCINFO_FILTER_MIN_SIZE) > +#define ALLOCINFO_FILTER_MASK_MAX_SIZE (1 << ALLOCINFO_FILTER_MAX_SIZE) > > #define ALLOCINFO_FILTER_MASKS \ > ((1 << (__ALLOCINFO_FILTER_LAST + 1)) - 1) > @@ -53,6 +57,8 @@ enum { > struct allocinfo_filter { > __u64 mask; /* bitmask of the filter fields used */ > struct allocinfo_tag fields; > + __u64 min_size; > + __u64 max_size; > }; > > struct allocinfo_get_at { > diff --git a/lib/alloc_tag.c b/lib/alloc_tag.c > index 93bc976ac505..ddc6946f56ab 100644 > --- a/lib/alloc_tag.c > +++ b/lib/alloc_tag.c > @@ -191,15 +191,26 @@ static int allocinfo_cmp_str(const char *str, const char *template) > return strncmp(allocinfo_str(str), template, ALLOCINFO_STR_SIZE); > } > > +/* Fetch the per-CPU counters */ > +static inline struct alloc_tag_counters allocinfo_prefetch_counters(struct codetag *ct) > +{ > + return alloc_tag_read(ct_to_alloc_tag(ct)); > +} > + > /* > * Populates the UAPI allocinfo_tag_data structure with active runtime > * profiling counters extracted from the given kernel codetag. > */ > static void allocinfo_to_params(struct codetag *ct, > - struct allocinfo_tag_data *data) > + struct allocinfo_tag_data *data, > + struct alloc_tag_counters *counters) > { > - struct alloc_tag *tag = ct_to_alloc_tag(ct); > - struct alloc_tag_counters counter = alloc_tag_read(tag); > + struct alloc_tag_counters local_counters; > + > + if (!counters) { > + local_counters = allocinfo_prefetch_counters(ct); > + counters = &local_counters; > + } > > if (ct->modname) > allocinfo_copy_str(data->tag.modname, ct->modname); > @@ -208,9 +219,9 @@ static void allocinfo_to_params(struct codetag *ct, > allocinfo_copy_str(data->tag.function, ct->function); > allocinfo_copy_str(data->tag.filename, ct->filename); > data->tag.lineno = ct->lineno; > - data->counter.bytes = counter.bytes; > - data->counter.calls = counter.calls; > - data->counter.accurate = !alloc_tag_is_inaccurate(tag); > + data->counter.bytes = counters->bytes; > + data->counter.calls = counters->calls; > + data->counter.accurate = !alloc_tag_is_inaccurate(ct_to_alloc_tag(ct)); > } > > /* > @@ -234,7 +245,9 @@ static int allocinfo_ioctl_get_content_id(struct seq_file *m, void __user *arg) > * Verifies whether a given codetag satisfies the active filtering criteria by > * matching it's characteristics against the specified filter. > */ > -static bool matches_filter(struct codetag *ct, struct allocinfo_filter *filter) > +static bool matches_filter(struct codetag *ct, struct allocinfo_filter *filter, > + struct alloc_tag_counters *counters, > + bool *fetched_counters) > { > if (!filter || !filter->mask) > return true; > @@ -247,20 +260,34 @@ static bool matches_filter(struct codetag *ct, struct allocinfo_filter *filter) > return false; > } else if (allocinfo_cmp_str(ct->modname, filter->fields.modname)) > return false; > + } It seems an extra } was accidentally added here > } > > if ((filter->mask & ALLOCINFO_FILTER_MASK_FUNCTION) && > - ct->function && (allocinfo_cmp_str(ct->function, filter->fields.function))) > + ct->function && allocinfo_cmp_str(ct->function, filter->fields.function)) > return false; > This should be fixed in the second patch; it's unrelated to current functionality. > if ((filter->mask & ALLOCINFO_FILTER_MASK_FILENAME) && > - ct->filename && (allocinfo_cmp_str(ct->filename, filter->fields.filename))) > + ct->filename && allocinfo_cmp_str(ct->filename, filter->fields.filename)) > return false; Ditto Thanks Best Regards Hao > if ((filter->mask & ALLOCINFO_FILTER_MASK_LINENO) && > ct->lineno != filter->fields.lineno) > return false; > > + if (filter->mask & (ALLOCINFO_FILTER_MASK_MIN_SIZE | ALLOCINFO_FILTER_MASK_MAX_SIZE)) { > + if (!*fetched_counters) { > + *counters = allocinfo_prefetch_counters(ct); > + *fetched_counters = true; > + } > + if ((filter->mask & ALLOCINFO_FILTER_MASK_MIN_SIZE) && > + counters->bytes < filter->min_size) > + return false; > + if ((filter->mask & ALLOCINFO_FILTER_MASK_MAX_SIZE) && > + counters->bytes > filter->max_size) > + return false; > + } > + > return true; > } > > @@ -274,6 +301,8 @@ static int allocinfo_ioctl_get_at(struct seq_file *m, void __user *arg) > struct codetag *ct; > struct allocinfo_get_at params = {0}; > __u64 skip_count; > + struct alloc_tag_counters counters; > + bool fetched_counters; > > if (copy_from_user(¶ms, arg, sizeof(params))) > return -EFAULT; > @@ -281,6 +310,11 @@ static int allocinfo_ioctl_get_at(struct seq_file *m, void __user *arg) > if (params.filter.mask & ~ALLOCINFO_FILTER_MASKS) > return -EINVAL; > > + if ((params.filter.mask & ALLOCINFO_FILTER_MASK_MIN_SIZE) && > + (params.filter.mask & ALLOCINFO_FILTER_MASK_MAX_SIZE) && > + params.filter.min_size > params.filter.max_size) > + return -EINVAL; > + > priv = m->private; > > mutex_lock(&priv->ioctl_lock); > @@ -304,7 +338,8 @@ static int allocinfo_ioctl_get_at(struct seq_file *m, void __user *arg) > ct = codetag_next_ct(&priv->ioctl_iter); > > while (ct) { > - if (matches_filter(ct, &priv->filter)) { > + fetched_counters = false; > + if (matches_filter(ct, &priv->filter, &counters, &fetched_counters)) { > if (skip_count == 0) > break; > skip_count--; > @@ -313,7 +348,7 @@ static int allocinfo_ioctl_get_at(struct seq_file *m, void __user *arg) > } > > if (ct) { > - allocinfo_to_params(ct, ¶ms.data); > + allocinfo_to_params(ct, ¶ms.data, fetched_counters ? &counters : NULL); > priv->positioned = true; > } > > @@ -339,6 +374,8 @@ static int allocinfo_ioctl_get_next(struct seq_file *m, void __user *arg) > struct codetag *ct; > struct allocinfo_tag_data params; > int ret = 0; > + struct alloc_tag_counters counters; > + bool fetched_counters; > > memset(¶ms, 0, sizeof(params)); > priv = m->private; > @@ -352,10 +389,15 @@ static int allocinfo_ioctl_get_next(struct seq_file *m, void __user *arg) > } > > ct = codetag_next_ct(&priv->ioctl_iter); > - while (ct && !matches_filter(ct, &priv->filter)) > + while (ct) { > + fetched_counters = false; > + if (matches_filter(ct, &priv->filter, &counters, &fetched_counters)) > + break; > ct = codetag_next_ct(&priv->ioctl_iter); > + } > + > if (ct) > - allocinfo_to_params(ct, ¶ms); > + allocinfo_to_params(ct, ¶ms, fetched_counters ? &counters : NULL); > > if (!ct) { > priv->positioned = false;