From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 3E2F3217673 for ; Mon, 17 Mar 2025 05:13:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742188416; cv=none; b=sCQuy58XD0Z9Ue6MeLPE25UgqwueGZ6ghpZ8k2GJwsB8gBdEsju5KwdpuWjqPzFgW+dl9DQeeeIhRvDE7imSteknqupYK41F/73KksXYpOaU/fDLRe7jN/Ok/Kf7FLtC5aSTiFQiMl4itbzhCNcjaym2MAMzhfzEJlkLQJ8yEaM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742188416; c=relaxed/simple; bh=MDaHWarqfN/apLmMOLvsgsmX0b70HCnzZWOXkpXw19A=; h=Date:To:From:Subject:Message-Id; b=Kr3lWFxCAtYdhkNbgCpb4pUUObtJsrUCSUFPsZ/nPuAl9ez/ZSXh8ArVTlZ4hyvtSDU7lywpnB9sScAOiKpN6TWeO4lPqcORKjgiIekS+dBAt/yAmer7UXWTXgGiEZWsTPKHMdew4bLKG3VKtommLnjNetdUVql9uFQl2a3oU50= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=e6/069uI; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="e6/069uI" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 12D75C4CEEC; Mon, 17 Mar 2025 05:13:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1742188416; bh=MDaHWarqfN/apLmMOLvsgsmX0b70HCnzZWOXkpXw19A=; h=Date:To:From:Subject:From; b=e6/069uItKVUGFdHd9Ljc1KKNWt36+x83gD2tfk7NZFvXZDdWEvcXAz9B2iu3xYLe PQ5ZOcLhlC2/RLCPvOIdhwYXdqBz9TR6qmBtWlco+eJDUf8wSKcHVAxf9Ng0dwZXVB hiT/moEUek6ew4cFJvM3Jvuz18MxBJ+lJLlQLJ7s= Date: Sun, 16 Mar 2025 22:13:35 -0700 To: mm-commits@vger.kernel.org,yosry.ahmed@linux.dev,ryncsn@gmail.com,minchan@kernel.org,hdanton@sina.com,bigeasy@linutronix.de,senozhatsky@chromium.org,akpm@linux-foundation.org From: Andrew Morton Subject: [merged mm-stable] zram-remove-second-stage-of-handle-allocation.patch removed from -mm tree Message-Id: <20250317051336.12D75C4CEEC@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The quilt patch titled Subject: zram: remove second stage of handle allocation has been removed from the -mm tree. Its filename was zram-remove-second-stage-of-handle-allocation.patch This patch was dropped because it was merged into the mm-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm ------------------------------------------------------ From: Sergey Senozhatsky Subject: zram: remove second stage of handle allocation Date: Mon, 3 Mar 2025 11:03:14 +0900 Previously zram write() was atomic which required us to pass __GFP_KSWAPD_RECLAIM to zsmalloc handle allocation on a fast path and attempt a slow path allocation (with recompression) if the fast path failed. Since we are not in atomic context anymore we can permit direct reclaim during handle allocation, and hence can have a single allocation path. There is no slow path anymore so we don't unlock per-CPU stream (and don't lose compressed data) which means that there is no need to do recompression now (which should reduce CPU and battery usage). Link: https://lkml.kernel.org/r/20250303022425.285971-6-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky Cc: Hillf Danton Cc: Kairui Song Cc: Minchan Kim Cc: Sebastian Andrzej Siewior Cc: Yosry Ahmed Signed-off-by: Andrew Morton --- drivers/block/zram/zram_drv.c | 39 +++++--------------------------- 1 file changed, 7 insertions(+), 32 deletions(-) --- a/drivers/block/zram/zram_drv.c~zram-remove-second-stage-of-handle-allocation +++ a/drivers/block/zram/zram_drv.c @@ -1723,11 +1723,11 @@ static int write_incompressible_page(str static int zram_write_page(struct zram *zram, struct page *page, u32 index) { int ret = 0; - unsigned long handle = -ENOMEM; - unsigned int comp_len = 0; + unsigned long handle; + unsigned int comp_len; void *dst, *mem; struct zcomp_strm *zstrm; - unsigned long element = 0; + unsigned long element; bool same_filled; /* First, free memory allocated to this slot (if any) */ @@ -1741,7 +1741,6 @@ static int zram_write_page(struct zram * if (same_filled) return write_same_filled_page(zram, element, index); -compress_again: zstrm = zcomp_stream_get(zram->comps[ZRAM_PRIMARY_COMP]); mem = kmap_local_page(page); ret = zcomp_compress(zram->comps[ZRAM_PRIMARY_COMP], zstrm, @@ -1751,7 +1750,6 @@ compress_again: if (unlikely(ret)) { zcomp_stream_put(zstrm); pr_err("Compression failed! err=%d\n", ret); - zs_free(zram->mem_pool, handle); return ret; } @@ -1760,35 +1758,12 @@ compress_again: return write_incompressible_page(zram, page, index); } - /* - * handle allocation has 2 paths: - * a) fast path is executed with preemption disabled (for - * per-cpu streams) and has __GFP_DIRECT_RECLAIM bit clear, - * since we can't sleep; - * b) slow path enables preemption and attempts to allocate - * the page with __GFP_DIRECT_RECLAIM bit set. we have to - * put per-cpu compression stream and, thus, to re-do - * the compression once handle is allocated. - * - * if we have a 'non-null' handle here then we are coming - * from the slow path and handle has already been allocated. - */ - if (IS_ERR_VALUE(handle)) - handle = zs_malloc(zram->mem_pool, comp_len, - __GFP_KSWAPD_RECLAIM | - __GFP_NOWARN | - __GFP_HIGHMEM | - __GFP_MOVABLE); + handle = zs_malloc(zram->mem_pool, comp_len, + GFP_NOIO | __GFP_NOWARN | + __GFP_HIGHMEM | __GFP_MOVABLE); if (IS_ERR_VALUE(handle)) { zcomp_stream_put(zstrm); - atomic64_inc(&zram->stats.writestall); - handle = zs_malloc(zram->mem_pool, comp_len, - GFP_NOIO | __GFP_HIGHMEM | - __GFP_MOVABLE); - if (IS_ERR_VALUE(handle)) - return PTR_ERR((void *)handle); - - goto compress_again; + return PTR_ERR((void *)handle); } if (!zram_can_store_page(zram)) { _ Patches currently in -mm which might be from senozhatsky@chromium.org are