s390/cpum_sf: Use kzalloc and minor changes

[ Upstream commit 32dab6828c ]

Use kzalloc() to allocate auxiliary buffer structure initialized
with all zeroes to avoid random value in trace output.

Avoid double access to SBD hardware flags.

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Thomas Richter
2019-12-19 14:56:13 +01:00
committed by Greg Kroah-Hartman
parent 2708ed6048
commit a356441de6

View File

@@ -1377,8 +1377,8 @@ static int aux_output_begin(struct perf_output_handle *handle,
idx = aux->empty_mark + 1;
for (i = 0; i < range_scan; i++, idx++) {
te = aux_sdb_trailer(aux, idx);
te->flags = te->flags & ~SDB_TE_BUFFER_FULL_MASK;
te->flags = te->flags & ~SDB_TE_ALERT_REQ_MASK;
te->flags &= ~(SDB_TE_BUFFER_FULL_MASK |
SDB_TE_ALERT_REQ_MASK);
te->overflow = 0;
}
/* Save the position of empty SDBs */
@@ -1425,8 +1425,7 @@ static bool aux_set_alert(struct aux_buffer *aux, unsigned long alert_index,
te = aux_sdb_trailer(aux, alert_index);
do {
orig_flags = te->flags;
orig_overflow = te->overflow;
*overflow = orig_overflow;
*overflow = orig_overflow = te->overflow;
if (orig_flags & SDB_TE_BUFFER_FULL_MASK) {
/*
* SDB is already set by hardware.
@@ -1660,7 +1659,7 @@ static void *aux_buffer_setup(struct perf_event *event, void **pages,
}
/* Allocate aux_buffer struct for the event */
aux = kmalloc(sizeof(struct aux_buffer), GFP_KERNEL);
aux = kzalloc(sizeof(struct aux_buffer), GFP_KERNEL);
if (!aux)
goto no_aux;
sfb = &aux->sfb;