From: Thomas Richter Date: Thu, 19 Dec 2019 13:56:13 +0000 (+0100) Subject: s390/cpum_sf: Use kzalloc and minor changes X-Git-Tag: v5.4.69~294 X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=4f726a2afb99f1ba2d8af4251c0b44562511cf7a;p=users%2Fdwmw2%2Flinux.git s390/cpum_sf: Use kzalloc and minor changes [ Upstream commit 32dab6828c42f087439d3e2617dc7283546bd8f7 ] 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 Signed-off-by: Vasily Gorbik Signed-off-by: Sasha Levin --- diff --git a/arch/s390/kernel/perf_cpum_sf.c b/arch/s390/kernel/perf_cpum_sf.c index 229e1e2f8253a..996e447ead3a6 100644 --- a/arch/s390/kernel/perf_cpum_sf.c +++ b/arch/s390/kernel/perf_cpum_sf.c @@ -1429,8 +1429,8 @@ 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 */ @@ -1477,8 +1477,7 @@ 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. @@ -1712,7 +1711,7 @@ 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;