Re: [PATCH 01/28] ibtrs: add header shared between ibtrs_client and ibtrs_server

On Fri, Mar 24, 2017 at 11:45:16AM +0100, Jack Wang wrote:

From: Jack Wang <redacted>

Signed-off-by: Jack Wang <redacted>
Signed-off-by: Kleber Souza <redacted>
Signed-off-by: Danil Kipnis <redacted>
Signed-off-by: Roman Pen <redacted>
---

[...]

+
+#define XX(a) case (a): return #a

please no macros with retun in them and XX isn't quite too descriptive as
well.

[...]

+static inline const char *ib_wc_opcode_str(enum ib_wc_opcode opcode)
+{
+	switch (opcode) {
+	XX(IB_WC_SEND);
+	XX(IB_WC_RDMA_WRITE);
+	XX(IB_WC_RDMA_READ);
+	XX(IB_WC_COMP_SWAP);
+	XX(IB_WC_FETCH_ADD);
+	/* recv-side); inbound completion */
+	XX(IB_WC_RECV);
+	XX(IB_WC_RECV_RDMA_WITH_IMM);
+	default: return "IB_WC_OPCODE_UNKNOWN";
+	}
+}

How about:

struct {
	char *name;
	enum ib_wc_opcode opcode;
} ib_wc_opcode_table[] = {
	{ stringyfy(IB_WC_SEND), IB_WC_SEND },
	{ stringyfy(IB_WC_RDMA_WRITE), IB_WC_RDMA_WRITE },
	{ stringyfy(IB_WC_RDMA_READ ), IB_WC_RDMA_READ }
	{ stringyfy(IB_WC_COMP_SWAP), IB_WC_COMP_SWAP },
	{ stringyfy(IB_WC_FETCH_ADD), IB_WC_FETCH_ADD },
	{ stringyfy(IB_WC_RECV), IB_WC_RECV },
	{ stringyfy(IB_WC_RECV_RDMA_WITH_IMM), IB_WC_RECV_RDMA_WITH_IMM },
	{ NULL, 0 },
};

static inline const char *ib_wc_opcode_str(enum ib_wc_opcode opcode)
{
	int i;

	for (i = 0; i < ARRAY_SIZE(ib_wc_opcode_table); i++)
		if (ib_wc_opcode_table[i].opcode == opcode)
			return ib_wc_opcode_table[i].name;

	return "IB_WC_OPCODE_UNKNOWN";
}


[...]

+/**
+ * struct ibtrs_msg_hdr - Common header of all IBTRS messages
+ * @type:	Message type, valid values see: enum ibtrs_msg_types
+ * @tsize:	Total size of transferred data
+ *
+ * Don't move the first 8 padding bytes! It's a workaround for a kernel bug.
+ * See IBNBD-610 for details

What about resolving the kernel bug instead of making workarounds?

+ *
+ * DO NOT CHANGE!
+ */
+struct ibtrs_msg_hdr {
+	u8			__padding1;
+	u8			type;
+	u16			__padding2;
+	u32			tsize;
+};

[...]

-- 
Johannes Thumshirn                                          Storage
jthumshirn@suse.de                                +49 911 74053 689
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