x86,intel_iommu: Replace cmpxchg_double()

Peter Zijlstra committed 3 years ago

Commit b1fe7f21 parent 0a0a6802 files · +68 −65Browse files

Unified · Split

2 files

drivers/iommu/intel/irq_remapping.c +2 −6
include/linux/dmar.h +66 −59

 	irte = &iommu->ir_table->base[index];
 	if ((irte->pst == 1) || (irte_modified->pst == 1)) {
-		bool ret;
-		ret = cmpxchg_double(&irte->low, &irte->high,
-				     irte->low, irte->high,
-				     irte_modified->low, irte_modified->high);
 		/*
 		 * We use cmpxchg16 to atomically update the 128-bit IRTE,
 		 * and it cannot be updated by the hardware or other processors
 		 * behind us, so the return value of cmpxchg16 should be the
 		 * same as the old value.
 		 */
-		WARN_ON(!ret);
+		u128 old = irte->irte;
+		WARN_ON(!try_cmpxchg128(&irte->irte, &old, irte_modified->irte));
 	} else {
 		WRITE_ONCE(irte->low, irte_modified->low);
 		WRITE_ONCE(irte->high, irte_modified->high);

include/linux/dmar.h+66−59

@@ -202,67 +202,74 @@ static inline void detect_intel_iommu(void) · 201 unmodified lines
202		202
203	struct irte {	203	struct irte {
204	union {	204	union {
205	/* Shared between remapped and posted mode*/
206	struct {	205	struct {
207	__u64 present : 1, /* 0 */	206	union {
208	fpd : 1, /* 1 */	207	/* Shared between remapped and posted mode*/
209	__res0 : 6, /* 2 - 6 */	208	struct {
210	avail : 4, /* 8 - 11 */	209	__u64 present : 1, /* 0 */
211	__res1 : 3, /* 12 - 14 */	210	fpd : 1, /* 1 */
212	pst : 1, /* 15 */	211	__res0 : 6, /* 2 - 6 */
213	vector : 8, /* 16 - 23 */	212	avail : 4, /* 8 - 11 */
214	__res2 : 40; /* 24 - 63 */	213	__res1 : 3, /* 12 - 14 */
		214	pst : 1, /* 15 */
		215	vector : 8, /* 16 - 23 */
		216	__res2 : 40; /* 24 - 63 */
		217	};
		218
		219	/* Remapped mode */
		220	struct {
		221	__u64 r_present : 1, /* 0 */
		222	r_fpd : 1, /* 1 */
		223	dst_mode : 1, /* 2 */
		224	redir_hint : 1, /* 3 */
		225	trigger_mode : 1, /* 4 */
		226	dlvry_mode : 3, /* 5 - 7 */
		227	r_avail : 4, /* 8 - 11 */
		228	r_res0 : 4, /* 12 - 15 */
		229	r_vector : 8, /* 16 - 23 */
		230	r_res1 : 8, /* 24 - 31 */
		231	dest_id : 32; /* 32 - 63 */
		232	};
		233
		234	/* Posted mode */
		235	struct {
		236	__u64 p_present : 1, /* 0 */
		237	p_fpd : 1, /* 1 */
		238	p_res0 : 6, /* 2 - 7 */
		239	p_avail : 4, /* 8 - 11 */
		240	p_res1 : 2, /* 12 - 13 */
		241	p_urgent : 1, /* 14 */
		242	p_pst : 1, /* 15 */
		243	p_vector : 8, /* 16 - 23 */
		244	p_res2 : 14, /* 24 - 37 */
		245	pda_l : 26; /* 38 - 63 */
		246	};
		247	__u64 low;
		248	};
		249
		250	union {
		251	/* Shared between remapped and posted mode*/
		252	struct {
		253	__u64 sid : 16, /* 64 - 79 */
		254	sq : 2, /* 80 - 81 */
		255	svt : 2, /* 82 - 83 */
		256	__res3 : 44; /* 84 - 127 */
		257	};
		258
		259	/* Posted mode*/
		260	struct {
		261	__u64 p_sid : 16, /* 64 - 79 */
		262	p_sq : 2, /* 80 - 81 */
		263	p_svt : 2, /* 82 - 83 */
		264	p_res3 : 12, /* 84 - 95 */
		265	pda_h : 32; /* 96 - 127 */
		266	};
		267	__u64 high;
		268	};
215	};	269	};
216		270	#ifdef CONFIG_IRQ_REMAP
217	/* Remapped mode */	271	__u128 irte;
218	struct {	272	#endif
219	__u64 r_present : 1, /* 0 */
220	r_fpd : 1, /* 1 */
221	dst_mode : 1, /* 2 */
222	redir_hint : 1, /* 3 */
223	trigger_mode : 1, /* 4 */
224	dlvry_mode : 3, /* 5 - 7 */
225	r_avail : 4, /* 8 - 11 */
226	r_res0 : 4, /* 12 - 15 */
227	r_vector : 8, /* 16 - 23 */
228	r_res1 : 8, /* 24 - 31 */
229	dest_id : 32; /* 32 - 63 */
230	};
231
232	/* Posted mode */
233	struct {
234	__u64 p_present : 1, /* 0 */
235	p_fpd : 1, /* 1 */
236	p_res0 : 6, /* 2 - 7 */
237	p_avail : 4, /* 8 - 11 */
238	p_res1 : 2, /* 12 - 13 */
239	p_urgent : 1, /* 14 */
240	p_pst : 1, /* 15 */
241	p_vector : 8, /* 16 - 23 */
242	p_res2 : 14, /* 24 - 37 */
243	pda_l : 26; /* 38 - 63 */
244	};
245	__u64 low;
246	};
247
248	union {
249	/* Shared between remapped and posted mode*/
250	struct {
251	__u64 sid : 16, /* 64 - 79 */
252	sq : 2, /* 80 - 81 */
253	svt : 2, /* 82 - 83 */
254	__res3 : 44; /* 84 - 127 */
255	};
256
257	/* Posted mode*/
258	struct {
259	__u64 p_sid : 16, /* 64 - 79 */
260	p_sq : 2, /* 80 - 81 */
261	p_svt : 2, /* 82 - 83 */
262	p_res3 : 12, /* 84 - 95 */
263	pda_h : 32; /* 96 - 127 */
264	};
265	__u64 high;
266	};	273	};
267	};	274	};
268		275

x86,intel_iommu: Replace cmpxchg_double()

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