linux-kernel - Re: [PATCH 1/3] vmalloc: Add __vmalloc_node_try

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Message-ID: <20180620222653.GC11479@bombadil.infradead.org>
Date:   Wed, 20 Jun 2018 15:26:53 -0700
From:   Matthew Wilcox <willy@...radead.org>
To:     Rick Edgecombe <rick.p.edgecombe@...el.com>
Cc:     tglx@...utronix.de, mingo@...hat.com, hpa@...or.com,
        x86@...nel.org, linux-kernel@...r.kernel.org, linux-mm@...ck.org,
        kernel-hardening@...ts.openwall.com, kristen.c.accardi@...el.com,
        dave.hansen@...el.com, arjan.van.de.ven@...el.com
Subject: Re: [PATCH 1/3] vmalloc: Add __vmalloc_node_try_addr function

On Wed, Jun 20, 2018 at 03:09:28PM -0700, Rick Edgecombe wrote:
>  
>  /**
> + *	__vmalloc_try_addr  -  try to alloc at a specific address
> + *	@addr:		address to try
> + *	@size:		size to try
> + *	@gfp_mask:	flags for the page level allocator
> + *	@prot:		protection mask for the allocated pages
> + *	@vm_flags:	additional vm area flags (e.g. %VM_NO_GUARD)
> + *	@node:		node to use for allocation or NUMA_NO_NODE
> + *	@caller:	caller's return address
> + *
> + *	Try to allocate at the specific address. If it succeeds the address is
> + *	returned. If it fails NULL is returned.  It may trigger TLB flushes.

 * Try to allocate memory at a specific address.  May trigger TLB flushes.
 *
 * Context: Process context.
 * Return: The allocated address if it succeeds.  NULL if it fails.

> @@ -1759,8 +1795,9 @@ void *__vmalloc_node_range(unsigned long size, unsigned long align,
>  	return addr;
>  
>  fail:
> -	warn_alloc(gfp_mask, NULL,
> -			  "vmalloc: allocation failure: %lu bytes", real_size);
> +	if (!(gfp_mask & __GFP_NOWARN))
> +		warn_alloc(gfp_mask, NULL,
> +			"vmalloc: allocation failure: %lu bytes", real_size);
>  	return NULL;

Not needed:

void warn_alloc(gfp_t gfp_mask, nodemask_t *nodemask, const char *fmt, ...)
{
...
        if ((gfp_mask & __GFP_NOWARN) || !__ratelimit(&nopage_rs))
                return;