Commit 2171787b authored by Pallipadi, Venkatesh's avatar Pallipadi, Venkatesh Committed by H. Peter Anvin
Browse files

x86: avoid back to back on_each_cpu in cpa_flush_array 



Cleanup cpa_flush_array() to avoid back to back on_each_cpu() calls.

[ Impact: optimizes fix 0af48f42 ]

Signed-off-by: default avatarVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: default avatarH. Peter Anvin <hpa@zytor.com>
parent 46176b4f

arch/x86/mm/pageattr.c

+3 −14
Original line number Diff line number Diff line
@@ -204,30 +204,19 @@ static void cpa_flush_range(unsigned long start, int numpages, int cache) 
	}

}



static void wbinvd_local(void *unused)

{

	wbinvd();

}



static void cpa_flush_array(unsigned long *start, int numpages, int cache,

			    int in_flags, struct page **pages)

{

	unsigned int i, level;

	unsigned long do_wbinvd = cache && numpages >= 1024; /* 4M threshold */



	BUG_ON(irqs_disabled());



	on_each_cpu(__cpa_flush_range, NULL, 1);

	on_each_cpu(__cpa_flush_all, (void *) do_wbinvd, 1);



	if (!cache)

	if (!cache || do_wbinvd)

		return;



	/* 4M threshold */

	if (numpages >= 1024) {

		if (boot_cpu_data.x86 >= 4)

			on_each_cpu(wbinvd_local, NULL, 1);



		return;

	}

	/*

	 * We only need to flush on one CPU,

	 * clflush is a MESI-coherent instruction that