Commit 497cc42b authored by Peter Zijlstra's avatar Peter Zijlstra
Browse files

s390/cpum_sf: Convert to cmpxchg128() 



Now that there is a cross arch u128 and cmpxchg128(), use those
instead of the custom CDSG helper.

Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: default avatarArnd Bergmann <arnd@arndb.de>
Reviewed-by: default avatarMark Rutland <mark.rutland@arm.com>
Acked-by: default avatarHeiko Carstens <hca@linux.ibm.com>
Tested-by: default avatarMark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20230531132324.058821078@infradead.org
parent febe950d

arch/s390/include/asm/cpu_mf.h

+1 −1
Original line number Diff line number Diff line
@@ -140,7 +140,7 @@ union hws_trailer_header { 
		unsigned int dsdes:16;	/* 48-63: size of diagnostic SDE */

		unsigned long long overflow; /* 64 - Overflow Count   */

	};

	__uint128_t val;

	u128 val;

};



struct hws_trailer_entry {

arch/s390/kernel/perf_cpum_sf.c

+3 −13
Original line number Diff line number Diff line
@@ -1271,16 +1271,6 @@ static void hw_collect_samples(struct perf_event *event, unsigned long *sdbt, 
	}

}



static inline __uint128_t __cdsg(__uint128_t *ptr, __uint128_t old, __uint128_t new)

{

	asm volatile(

		"	cdsg	%[old],%[new],%[ptr]\n"

		: [old] "+d" (old), [ptr] "+QS" (*ptr)

		: [new] "d" (new)

		: "memory", "cc");

	return old;

}



/* hw_perf_event_update() - Process sampling buffer

 * @event:	The perf event

 * @flush_all:	Flag to also flush partially filled sample-data-blocks
@@ -1352,7 +1342,7 @@ static void hw_perf_event_update(struct perf_event *event, int flush_all) 
			new.f = 0;

			new.a = 1;

			new.overflow = 0;

			prev.val = __cdsg(&te->header.val, old.val, new.val);

			prev.val = cmpxchg128(&te->header.val, old.val, new.val);

		} while (prev.val != old.val);



		/* Advance to next sample-data-block */
@@ -1562,7 +1552,7 @@ static bool aux_set_alert(struct aux_buffer *aux, unsigned long alert_index, 
		}

		new.a = 1;

		new.overflow = 0;

		prev.val = __cdsg(&te->header.val, old.val, new.val);

		prev.val = cmpxchg128(&te->header.val, old.val, new.val);

	} while (prev.val != old.val);

	return true;

}
@@ -1636,7 +1626,7 @@ static bool aux_reset_buffer(struct aux_buffer *aux, unsigned long range, 
				new.a = 1;

			else

				new.a = 0;

			prev.val = __cdsg(&te->header.val, old.val, new.val);

			prev.val = cmpxchg128(&te->header.val, old.val, new.val);

		} while (prev.val != old.val);

		*overflow += orig_overflow;

	}