From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-181.mta1.migadu.com (out-181.mta1.migadu.com [95.215.58.181]) (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 9D56E824A3 for ; Fri, 20 Mar 2026 06:02:16 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.181 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773986538; cv=none; b=oYSAYnH+N00Std10QgPYJb9G7GHpzs8WADjKAUEuCDuFYoUO1eneK3+a3Z1YO7dTdCt/t33hvgnF+dgo+pgW5u3T3Yl1l4tBKmdBWfl67jGfK8Owl17dAq1MacY5+0LAmsX1zlII3SwkxcL8WYxvAoMuOYEgnKUDo4NHFpA5ehk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773986538; c=relaxed/simple; bh=7gZTYvCYms6JLg4kbg3LMUFIljecloyM93oJfeULTjg=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=CIBySdHieGYDX1SXSJjHS9slFWGj7BGt/qP3qFZIHQ7Av+gVqK5QIrDBTjJHq/UF29k4+5NSwG7ylUMyV2AFsan0WcMcZxR5+TTBGrkLHuM9kLikcXlSUrPsx1MWASyVxHdojLi4/PVPX4Y79uUKSzlUf6k0XXGCMF22WkGBzBo= 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=lpL0/jza; arc=none smtp.client-ip=95.215.58.181 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="lpL0/jza" 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=1773986534; 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=YQcMr+CuWLq8RG6gUzwSk4dQyB0LcYdk73WHFDu273k=; b=lpL0/jza0612zsRwBePsrvNBAt5uG0PKzHE86KDZZ5y1svqlPoLcwO6GARh5LQpSkZ/z0w ZEyP0OGrRW8S7gCylv0mrqFALfnh4jxY5L7eap9/9VNV54pvzH65Hhz+vCeBFAnN0v2R/l cnkppksIyzHrkBfpGq6iO1/0Sh8xi1U= From: sunliming@linux.dev To: song@kernel.org, yukuai@fnnas.com, akpm@linux-foundation.org Cc: linux-raid@vger.kernel.org, linux-kernel@vger.kernel.org, sunliming Subject: [PATCH RESEND v3 1/3] lib/raid6: Divide the raid6 algorithm selection process into two parts Date: Fri, 20 Mar 2026 14:00:19 +0800 Message-Id: <20260320060021.30762-2-sunliming@linux.dev> In-Reply-To: <20260320060021.30762-1-sunliming@linux.dev> References: <20260320060021.30762-1-sunliming@linux.dev> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT From: sunliming Divide the RAID6 algorithm selection process into two parts: fast selection and benchmark selection. To prepare for the asynchronous processing of the benchmark phase. Signed-off-by: sunliming --- lib/raid6/algos.c | 76 +++++++++++++++++++++++++++++++++-------------- 1 file changed, 54 insertions(+), 22 deletions(-) diff --git a/lib/raid6/algos.c b/lib/raid6/algos.c index 799e0e5eac26..c21e3ad99d97 100644 --- a/lib/raid6/algos.c +++ b/lib/raid6/algos.c @@ -152,8 +152,32 @@ static inline const struct raid6_recov_calls *raid6_choose_recov(void) return best; } -static inline const struct raid6_calls *raid6_choose_gen( - void *(*const dptrs)[RAID6_TEST_DISKS], const int disks) +/* Quick selection: select the highest priority valid algorithm. */ +static inline int raid6_choose_gen_fast(void) +{ + int ret = 0; + const struct raid6_calls *const *algo; + const struct raid6_calls *best = NULL; + + for (best = NULL, algo = raid6_algos; *algo; algo++) + if (!best || (*algo)->priority > best->priority) + if (!(*algo)->valid || (*algo)->valid()) + best = *algo; + + if (best) { + raid6_call = *best; + pr_info("raid6: skipped pq benchmark and selected %s\n", + best->name); + } else { + pr_err("raid6: No valid algorithm found even for fast selection!\n"); + ret = -EINVAL; + } + + return ret; +} + +static inline const struct raid6_calls *raid6_gen_benchmark( + void *(*const dptrs)[RAID6_TEST_DISKS], const int disks) { unsigned long perf, bestgenperf, j0, j1; int start = (disks>>1)-1, stop = disks-3; /* work on the second half of the disks */ @@ -165,11 +189,6 @@ static inline const struct raid6_calls *raid6_choose_gen( if ((*algo)->valid && !(*algo)->valid()) continue; - if (!IS_ENABLED(CONFIG_RAID6_PQ_BENCHMARK)) { - best = *algo; - break; - } - perf = 0; preempt_disable(); @@ -200,12 +219,6 @@ static inline const struct raid6_calls *raid6_choose_gen( raid6_call = *best; - if (!IS_ENABLED(CONFIG_RAID6_PQ_BENCHMARK)) { - pr_info("raid6: skipped pq benchmark and selected %s\n", - best->name); - goto out; - } - pr_info("raid6: using algorithm %s gen() %ld MB/s\n", best->name, (bestgenperf * HZ * (disks - 2)) >> @@ -239,15 +252,13 @@ static inline const struct raid6_calls *raid6_choose_gen( /* Try to pick the best algorithm */ /* This code uses the gfmul table as convenient data set to abuse */ -int __init raid6_select_algo(void) +static int raid6_choose_gen_benmark(void) { const int disks = RAID6_TEST_DISKS; - const struct raid6_calls *gen_best; - const struct raid6_recov_calls *rec_best; char *disk_ptr, *p; void *dptrs[RAID6_TEST_DISKS]; - int i, cycle; + int i, cycle, ret = 0; /* prepare the buffer and fill it circularly with gfmul table */ disk_ptr = (char *)__get_free_pages(GFP_KERNEL, RAID6_TEST_DISKS_ORDER); @@ -269,15 +280,36 @@ int __init raid6_select_algo(void) if ((disks - 2) * PAGE_SIZE % 65536) memcpy(p, raid6_gfmul, (disks - 2) * PAGE_SIZE % 65536); - /* select raid gen_syndrome function */ - gen_best = raid6_choose_gen(&dptrs, disks); + gen_best = raid6_gen_benchmark(&dptrs, disks); + if (!gen_best) + ret = -EINVAL; + + free_pages((unsigned long)disk_ptr, RAID6_TEST_DISKS_ORDER); + + return ret; +} + +int __init raid6_select_algo(void) +{ + int ret = 0; + const struct raid6_recov_calls *rec_best = NULL; + + /* select raid gen_syndrome functions */ + if (!IS_ENABLED(CONFIG_RAID6_PQ_BENCHMARK)) + ret = raid6_choose_gen_fast(); + else + ret = raid6_choose_gen_benmark(); + + if (ret < 0) + goto out; /* select raid recover functions */ rec_best = raid6_choose_recov(); + if (!rec_best) + ret = -EINVAL; - free_pages((unsigned long)disk_ptr, RAID6_TEST_DISKS_ORDER); - - return gen_best && rec_best ? 0 : -EINVAL; +out: + return ret; } static void raid6_exit(void) -- 2.25.1