forked from rpms/glibc
		
	
		
			
				
	
	
		
			48 lines
		
	
	
		
			1.7 KiB
		
	
	
	
		
			Diff
		
	
	
	
	
	
			
		
		
	
	
			48 lines
		
	
	
		
			1.7 KiB
		
	
	
	
		
			Diff
		
	
	
	
	
	
| From 47f747217811db35854ea06741be3685e8bbd44d Mon Sep 17 00:00:00 2001
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| From: Noah Goldstein <goldstein.w.n@gmail.com>
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| Date: Mon, 17 Jul 2023 23:14:33 -0500
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| Subject: [PATCH] x86: Fix slight bug in `shared_per_thread` cache size
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|  calculation.
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| Content-type: text/plain; charset=UTF-8
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| 
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| After:
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| ```
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|     commit af992e7abdc9049714da76cae1e5e18bc4838fb8
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|     Author: Noah Goldstein <goldstein.w.n@gmail.com>
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|     Date:   Wed Jun 7 13:18:01 2023 -0500
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| 
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|         x86: Increase `non_temporal_threshold` to roughly `sizeof_L3 / 4`
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| ```
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| 
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| Split `shared` (cumulative cache size) from `shared_per_thread` (cache
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| size per socket), the `shared_per_thread` *can* be slightly off from
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| the previous calculation.
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| 
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| Previously we added `core` even if `threads_l2` was invalid, and only
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| used `threads_l2` to divide `core` if it was present. The changed
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| version only included `core` if `threads_l2` was valid.
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| 
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| This change restores the old behavior if `threads_l2` is invalid by
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| adding the entire value of `core`.
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| Reviewed-by: DJ Delorie <dj@redhat.com>
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| ---
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|  sysdeps/x86/dl-cacheinfo.h | 4 ++--
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|  1 file changed, 2 insertions(+), 2 deletions(-)
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| 
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| [DJ - ported to C8S]
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| 
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| diff -rup b1/sysdeps/x86/cacheinfo.h b2/sysdeps/x86/cacheinfo.h
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| --- b1/sysdeps/x86/cacheinfo.h	2023-08-08 13:44:55.185333601 -0400
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| +++ b2/sysdeps/x86/cacheinfo.h	2023-08-08 13:55:16.474680016 -0400
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| @@ -253,8 +253,8 @@ get_common_cache_info (long int *shared_
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|    /* Account for non-inclusive L2 and L3 caches.  */
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|    if (!inclusive_cache)
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|      {
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| -      if (threads_l2 > 0)
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| -	shared_per_thread += core / threads_l2;
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| +      long int core_per_thread = threads_l2 > 0 ? (core / threads_l2) : core;
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| +      shared_per_thread += core_per_thread;
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|        shared += core;
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|      }
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|  
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