Re: [PATCH v3 04/11] perf mem: Add statistics for peer snooping

[Arnaldo Carvalho de Melo <acme@kernel.org>]

Em Mon, May 23, 2022 at 09:38:31AM -0300, Arnaldo Carvalho de Melo escreveu:
> Em Wed, May 18, 2022 at 01:57:22PM +0800, Leo Yan escreveu:
> > Since the flag PERF_MEM_SNOOPX_PEER is added to support cache snooping
> > from peer cache line, it can come from a peer core, a peer cluster, or
> > a remote NUMA node.
> > 
> > This patch adds statistics for the flag PERF_MEM_SNOOPX_PEER.  Note, we
> > take PERF_MEM_SNOOPX_PEER as an affiliated info, it needs to cooperate
> > with cache level statistics.  Therefore, we account the load operations
> > for both the cache level's metrics (e.g. ld_l2hit, ld_llchit, etc.) and
> > the metric 'ld_peer' when flag PERF_MEM_SNOOPX_PEER is set.
> > 
> > Signed-off-by: Leo Yan <leo.yan@linaro.org>
> > Tested-by: Ali Saidi <alisaidi@amazon.com>
> 
> util/mem-events.c: In function ‘c2c_decode_stats’:
> util/mem-events.c:536:17: error: ‘PERF_MEM_SNOOPX_PEER’ undeclared (first use in this function); did you mean ‘PERF_MEM_SNOOPX_FWD’?

So I kept the first three patches:

⬢[acme@toolbox perf]$ git log --oneline -5
12aeaaba087d6d92 (HEAD -> perf/core) perf c2c: Update documentation for store metric 'N/A'
550b4d6f9a7e5ddc perf c2c: Add dimensions for 'N/A' metrics of store operation
9845063710725424 perf mem: Add stats for store operation with no available memory level
508c9fbce0d30da3 perf build: Error for BPF skeletons without LIBBPF
0869331fbaa2c11c Merge remote-tracking branch 'torvalds/master' into perf/core
⬢[acme@toolbox perf]$

With Jiri's ack, now waiting for clarification about the v9 discussion
on the base patchkit.

- Arnaldo
 
> 
> Should I fix this as suggested by the compiler?
> 
>   536 | #define P(a, b) PERF_MEM_##a##_##b
>       |                 ^~~~~~~~~
> util/mem-events.c:562:46: note: in expansion of macro ‘P’
>   562 |                                 if (snoopx & P(SNOOPX, PEER))
>       |                                              ^
> util/mem-events.c:536:17: note: each undeclared identifier is reported only once for each function it appears in
>   536 | #define P(a, b) PERF_MEM_##a##_##b
>       |                 ^~~~~~~~~
> util/mem-events.c:562:46: note: in expansion of macro ‘P’
>   562 |                                 if (snoopx & P(SNOOPX, PEER))
>       |                                              ^
> make[4]: *** [/var/home/acme/git/perf/tools/build/Makefile.build:96: /tmp/build/perf/util/mem-events.o] Error 1
> make[4]: *** Waiting for unfinished jobs....
>   LD      /tmp/build/perf/util/scripting-engines/perf-in.o
> make[3]: *** [/var/home/acme/git/perf/tools/build/Makefile.build:139: util] Error 2
> make[2]: *** [Makefile.perf:664: /tmp/build/perf/perf-in.o] Error 2
> make[1]: *** [Makefile.perf:240: sub-make] Error 2
> make: *** [Makefile:113: install-bin] Error 2
> make: Leaving directory '/var/home/acme/git/perf/tools/perf'
> 
>  Performance counter stats for 'make -k BUILD_BPF_SKEL=1 CORESIGHT=1 PYTHON=python3 O=/tmp/build/perf -C tools/perf install-bin':
> 
>     31,749,639,340      cycles:u
>     57,052,398,827      instructions:u            #    1.80  insn per cycle
> 
>        2.123830023 seconds time elapsed
> 
>        7.146520000 seconds user
>        1.707080000 seconds sys
> 
> 
> ⬢[acme@toolbox perf]$
> 
> > ---
> >  tools/perf/util/mem-events.c | 22 +++++++++++++++++++---
> >  tools/perf/util/mem-events.h |  1 +
> >  2 files changed, 20 insertions(+), 3 deletions(-)
> > 
> > diff --git a/tools/perf/util/mem-events.c b/tools/perf/util/mem-events.c
> > index 5dca1882c284..9de0eb3a1200 100644
> > --- a/tools/perf/util/mem-events.c
> > +++ b/tools/perf/util/mem-events.c
> > @@ -525,6 +525,7 @@ int c2c_decode_stats(struct c2c_stats *stats, struct mem_info *mi)
> >  	u64 op     = data_src->mem_op;
> >  	u64 lvl    = data_src->mem_lvl;
> >  	u64 snoop  = data_src->mem_snoop;
> > +	u64 snoopx = data_src->mem_snoopx;
> >  	u64 lock   = data_src->mem_lock;
> >  	u64 blk    = data_src->mem_blk;
> >  	/*
> > @@ -567,18 +568,28 @@ do {				\
> >  			if (lvl & P(LVL, IO))  stats->ld_io++;
> >  			if (lvl & P(LVL, LFB)) stats->ld_fbhit++;
> >  			if (lvl & P(LVL, L1 )) stats->ld_l1hit++;
> > -			if (lvl & P(LVL, L2 )) stats->ld_l2hit++;
> > +			if (lvl & P(LVL, L2)) {
> > +				stats->ld_l2hit++;
> > +
> > +				if (snoopx & P(SNOOPX, PEER))
> > +					stats->ld_peer++;
> > +			}
> >  			if (lvl & P(LVL, L3 )) {
> >  				if (snoop & P(SNOOP, HITM))
> >  					HITM_INC(lcl_hitm);
> >  				else
> >  					stats->ld_llchit++;
> > +
> > +				if (snoopx & P(SNOOPX, PEER))
> > +					stats->ld_peer++;
> >  			}
> >  
> >  			if (lvl & P(LVL, LOC_RAM)) {
> >  				stats->lcl_dram++;
> >  				if (snoop & P(SNOOP, HIT))
> >  					stats->ld_shared++;
> > +				else if (snoopx & P(SNOOPX, PEER))
> > +					stats->ld_peer++;
> >  				else
> >  					stats->ld_excl++;
> >  			}
> > @@ -597,10 +608,14 @@ do {				\
> >  		if ((lvl & P(LVL, REM_CCE1)) ||
> >  		    (lvl & P(LVL, REM_CCE2)) ||
> >  		     mrem) {
> > -			if (snoop & P(SNOOP, HIT))
> > +			if (snoop & P(SNOOP, HIT)) {
> >  				stats->rmt_hit++;
> > -			else if (snoop & P(SNOOP, HITM))
> > +			} else if (snoop & P(SNOOP, HITM)) {
> >  				HITM_INC(rmt_hitm);
> > +			} else if (snoopx & P(SNOOPX, PEER)) {
> > +				stats->rmt_hit++;
> > +				stats->ld_peer++;
> > +			}
> >  		}
> >  
> >  		if ((lvl & P(LVL, MISS)))
> > @@ -661,6 +676,7 @@ void c2c_add_stats(struct c2c_stats *stats, struct c2c_stats *add)
> >  	stats->ld_l1hit		+= add->ld_l1hit;
> >  	stats->ld_l2hit		+= add->ld_l2hit;
> >  	stats->ld_llchit	+= add->ld_llchit;
> > +	stats->ld_peer		+= add->ld_peer;
> >  	stats->lcl_hitm		+= add->lcl_hitm;
> >  	stats->rmt_hitm		+= add->rmt_hitm;
> >  	stats->tot_hitm		+= add->tot_hitm;
> > diff --git a/tools/perf/util/mem-events.h b/tools/perf/util/mem-events.h
> > index 8a8b568baeee..4879b841c841 100644
> > --- a/tools/perf/util/mem-events.h
> > +++ b/tools/perf/util/mem-events.h
> > @@ -75,6 +75,7 @@ struct c2c_stats {
> >  	u32	ld_l1hit;            /* count of loads that hit L1D */
> >  	u32	ld_l2hit;            /* count of loads that hit L2D */
> >  	u32	ld_llchit;           /* count of loads that hit LLC */
> > +	u32	ld_peer;             /* count of loads that hit peer core or cluster cache */
> >  	u32	lcl_hitm;            /* count of loads with local HITM  */
> >  	u32	rmt_hitm;            /* count of loads with remote HITM */
> >  	u32	tot_hitm;            /* count of loads with local and remote HITM */
> > -- 
> > 2.25.1
> 
> -- 
> 
> - Arnaldo

-- 

- Arnaldo