gianfar: convert u64 status counters to atomic64_t
While looking at some asm dump for an unrelated change, Eric
noticed in the following stats count increment code:
50b8: 81 3c 01 f8 lwz r9,504(r28)
50bc: 81 5c 01 fc lwz r10,508(r28)
50c0: 31 4a 00 01 addic r10,r10,1
50c4: 7d 29 01 94 addze r9,r9
50c8: 91 3c 01 f8 stw r9,504(r28)
50cc: 91 5c 01 fc stw r10,508(r28)
that a 64 bit counter was used on ppc-32 without sync
and hence the "ethtool -S" output was racy.
Here we convert all the values to use atomic64_t so that
the output will always be consistent.
Reported-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
diff --git a/drivers/net/ethernet/freescale/gianfar.h b/drivers/net/ethernet/freescale/gianfar.h
index 61b1785..78125f1 100644
--- a/drivers/net/ethernet/freescale/gianfar.h
+++ b/drivers/net/ethernet/freescale/gianfar.h
@@ -627,24 +627,25 @@
};
struct gfar_extra_stats {
- u64 kernel_dropped;
- u64 rx_large;
- u64 rx_short;
- u64 rx_nonoctet;
- u64 rx_crcerr;
- u64 rx_overrun;
- u64 rx_bsy;
- u64 rx_babr;
- u64 rx_trunc;
- u64 eberr;
- u64 tx_babt;
- u64 tx_underrun;
- u64 rx_skbmissing;
- u64 tx_timeout;
+ atomic64_t kernel_dropped;
+ atomic64_t rx_large;
+ atomic64_t rx_short;
+ atomic64_t rx_nonoctet;
+ atomic64_t rx_crcerr;
+ atomic64_t rx_overrun;
+ atomic64_t rx_bsy;
+ atomic64_t rx_babr;
+ atomic64_t rx_trunc;
+ atomic64_t eberr;
+ atomic64_t tx_babt;
+ atomic64_t tx_underrun;
+ atomic64_t rx_skbmissing;
+ atomic64_t tx_timeout;
};
#define GFAR_RMON_LEN ((sizeof(struct rmon_mib) - 16)/sizeof(u32))
-#define GFAR_EXTRA_STATS_LEN (sizeof(struct gfar_extra_stats)/sizeof(u64))
+#define GFAR_EXTRA_STATS_LEN \
+ (sizeof(struct gfar_extra_stats)/sizeof(atomic64_t))
/* Number of stats exported via ethtool */
#define GFAR_STATS_LEN (GFAR_RMON_LEN + GFAR_EXTRA_STATS_LEN)