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From: Mel Gorman <mgorman@suse.com>
To: NeilBrown <neilb@suse.de>
Cc: Chuck Lever III <chuck.lever@oracle.com>,
	Mike Javorski <mike.javorski@gmail.com>,
	Linux NFS Mailing List <linux-nfs@vger.kernel.org>,
	linux-mm@kvack.org
Subject: Re: [PATCH] MM: clarify effort used in alloc_pages_bulk_*()
Date: Mon, 30 Aug 2021 10:11:04 +0100	[thread overview]
Message-ID: <20210830091104.GA3997@suse.com> (raw)
In-Reply-To: <163027609524.7591.4987241695872857175@noble.neil.brown.name>

On Mon, Aug 30, 2021 at 08:28:15AM +1000, NeilBrown wrote:
> 
> The alloc_pages_bulk_*() interfaces do not make it clear what degree
> of success can be expected.
> 
> The code appears to allocate at least one page with the same effort as
> alloc_page() when used with the same GFP flags, and then to allocate any
> more only opportunistically.  So a caller should not *expect* to get a
> full allocation, but should not be *surprised* by one either.
> 
> Add text to the comment clarifying this.
> 
> Also fix a bug.  When alloc_pages_bulk_array() is called on an array
> that is partially allocated, the level of effort to get a single page is
> less than when the array was completely unallocated.  This behaviour is
> inconsistent, but now fixed.
> 
> Fixes: 0f87d9d30f21 ("mm/page_alloc: add an array-based interface to the bulk page allocator")
> Signed-off-by: NeilBrown <neilb@suse.de>

Acked-by: Mel Gorman <mgorman@suse.com>

-- 
Mel Gorman
SUSE Labs


      reply	other threads:[~2021-08-30  9:11 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <CAOv1SKCmdtchm5Z2NU80o49tkrHpAkPFaHKj4-vLDN5bZNCz-Q@mail.gmail.com>
     [not found] ` <162846730406.22632.14734595494457390936@noble.neil.brown.name>
     [not found]   ` <CAOv1SKBZ7sGBnvG9-M+De+s=CfU=H_GBs4hJah1E4ks+NSMyPw@mail.gmail.com>
     [not found]     ` <CAOv1SKCUM5cGuXWAc7dsXtbmPMATqd245juC+S9gVXHWiZsvmQ@mail.gmail.com>
     [not found]       ` <162855893202.12431.3423894387218130632@noble.neil.brown.name>
     [not found]         ` <CAOv1SKAaSbfw53LWCCrvGCHESgdtCf5h275Zkzi9_uHkqnCrdg@mail.gmail.com>
     [not found]           ` <162882238416.1695.4958036322575947783@noble.neil.brown.name>
     [not found]             ` <CAOv1SKB_dsam7P9pzzh_SKCtA8uE9cyFdJ=qquEfhLT42-szPA@mail.gmail.com>
     [not found]               ` <CAOv1SKDDOj5UeUwztrMSNJnLgSoEgD8OU55hqtLHffHvaCQzzA@mail.gmail.com>
     [not found]                 ` <162907681945.1695.10796003189432247877@noble.neil.brown.name>
     [not found]                   ` <87777C39-BDDA-4E1E-83FA-5B46918A66D3@oracle.com>
     [not found]                     ` <CAOv1SKA5ByO7PYQwvd6iBcPieWxEp=BfUZuigJ=7Hm4HAmTuMA@mail.gmail.com>
     [not found]                       ` <162915491276.9892.7049267765583701172@noble.neil.brown.name>
     [not found]                         ` <162941948235.9892.6790956894845282568@noble.neil.brown.name>
     [not found]                           ` <CAOv1SKAyr0Cixc8eQf8-Fdnf=9Db_xZGsweq9K2E5AkALFqavQ@mail.gmail.com>
     [not found]                             ` <CAOv1SKDDUFpgexZ_xYCe6c2-UCBK0+vicoG+LAtG2Zhispd_jg@mail.gmail.com>
     [not found]                               ` <162960371884.9892.13803244995043191094@noble.neil.brown.name>
     [not found]                                 ` <CAOv1SKBePD6N-R0uETgcSPA-LZZ4895ZJDKTY7mYvhfu184OQQ@mail.gmail.com>
     [not found]                                   ` <162966962721.9892.5962616727949224286@noble.neil.brown.name>
     [not found]                                     ` <CAOv1SKB6xqyduf5L5hcXOe-xMN-UJOfFeE5eXVga3TviKuH0PA@mail.gmail.com>
     [not found]                                       ` <163001427749.7591.7281634750945934559@noble.neil.brown.name>
     [not found]                                         ` <CAOv1SKC+3LXhM+L9MwU2D03bpeof55-g+i=r3SWEjVWcPVCi8Q@mail.gmail.com>
     [not found]                                           ` <163004202961.7591.12633163545286005205@noble.neil.brown.name>
     [not found]                                             ` <CAOv1SKDTcg5WDp5zf3ZGL0enJ7K693W-9TMYKcrgweyzp6Qjhg@mail.gmail.com>
     [not found]                                               ` <163004848514.7591.2757618782251492498@noble.neil.brown.name>
     [not found]                                                 ` <6CC9C852-CEE3-4657-86AD-9D5759E2BE1C@oracle.com>
     [not found]                                                   ` <CAOv1SKAiPB62sQcnDCKC5vYbbmakfbe80KRu3JEVZVO7Trk8cw@mail.gmail.com>
     [not found]                                                     ` <CAOv1SKATk1iP=J9r2x0CQzNuwq2VoRvN8Mkba3DsKq6W_tfrDQ@mail.gmail.com>
     [not found]                                                       ` <416268C9-BEAC-483C-9392-8139340BC849@oracle.com>
     [not found]                                                         ` <CAOv1SKCjvgSfUoFtufZ5-dB-quG=djnn-UHO286S410aVxrV0Q@mail.gmail.com>
     [not found]                                                           ` <12B831AA-4A4E-4102-ADA3-97B6FA0B119E@oracle.com>
2021-08-29 22:28                                                             ` NeilBrown
2021-08-30  9:11                                                               ` Mel Gorman [this message]

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