[tip: locking/core] s390/cpum_sf: Convert to cmpxchg128()

From: tip-bot2 for Peter Zijlstra
Date: Mon Jun 05 2023 - 03:42:58 EST


The following commit has been merged into the locking/core branch of tip:

Commit-ID: 497cc42bf53b55185ab3d39c634fbf09eb6681ae
Gitweb: https://git.kernel.org/tip/497cc42bf53b55185ab3d39c634fbf09eb6681ae
Author: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
AuthorDate: Wed, 31 May 2023 15:08:45 +02:00
Committer: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
CommitterDate: Mon, 05 Jun 2023 09:36:40 +02:00

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: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Reviewed-by: Arnd Bergmann <arnd@xxxxxxxx>
Reviewed-by: Mark Rutland <mark.rutland@xxxxxxx>
Acked-by: Heiko Carstens <hca@xxxxxxxxxxxxx>
Tested-by: Mark Rutland <mark.rutland@xxxxxxx>
Link: https://lore.kernel.org/r/20230531132324.058821078@xxxxxxxxxxxxx
---
arch/s390/include/asm/cpu_mf.h | 2 +-
arch/s390/kernel/perf_cpum_sf.c | 16 +++-------------
2 files changed, 4 insertions(+), 14 deletions(-)

diff --git a/arch/s390/include/asm/cpu_mf.h b/arch/s390/include/asm/cpu_mf.h
index 7e417d7..a0de5b9 100644
--- a/arch/s390/include/asm/cpu_mf.h
+++ b/arch/s390/include/asm/cpu_mf.h
@@ -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 {
diff --git a/arch/s390/kernel/perf_cpum_sf.c b/arch/s390/kernel/perf_cpum_sf.c
index 7ef72f5..8ecfbce 100644
--- a/arch/s390/kernel/perf_cpum_sf.c
+++ b/arch/s390/kernel/perf_cpum_sf.c
@@ -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;
}