PCI: Add pci_irq_type() to query the allocated interrupt typegrafted

Add a helper that returns PCI_IRQ_MSIX, PCI_IRQ_MSI, or PCI_IRQ_INTX
based on the interrupt type the PCI core selected after
pci_alloc_irq_vectors().

Several drivers already open-code this check against pdev->msix_enabled
and pdev->msi_enabled, or even open code this helper [1].

A common helper avoids the duplication and keeps drivers from accessing
the bitfield directly (see also [2]).

Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Tested-by: John Hubbard <jhubbard@nvidia.com>
Link: https://elixir.bootlin.com/linux/v7.1/source/drivers/net/ethernet/aquantia/atlantic/aq_pci_func.c#L196 [1]
Inspired-by: John Hubbard <jhubbard@nvidia.com>
Link: https://lore.kernel.org/all/DKKG2QM3YJYB.Z2H2B2UXJ75N@kernel.org/ [2]
Reviewed-by: Gary Guo <gary@garyguo.net>
Link: https://patch.msgid.link/20260813165234.620555-5-dakr@kernel.org
[ Add missing pci_irq_type() stub for CONFIG_PCI=n. ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>

1 files changed, 71 insertions, 0 deletions

diff --git a/tools/perf/util/rwsem.c b/tools/perf/util/rwsem.c
new file mode 100644
index 000000000..9d2683239
--- /dev/null
+++ b/tools/perf/util/rwsem.c
@@ -0,0 +1,71 @@
+// SPDX-License-Identifier: GPL-2.0
+#include "util.h"
+#include "rwsem.h"
+
+#if RWS_ERRORCHECK
+#include "mutex.h"
+#endif
+
+int init_rwsem(struct rw_semaphore *sem)
+{
+#if RWS_ERRORCHECK
+	mutex_init(&sem->mtx);
+	return 0;
+#else
+	return pthread_rwlock_init(&sem->lock, NULL);
+#endif
+}
+
+int exit_rwsem(struct rw_semaphore *sem)
+{
+#if RWS_ERRORCHECK
+	mutex_destroy(&sem->mtx);
+	return 0;
+#else
+	return pthread_rwlock_destroy(&sem->lock);
+#endif
+}
+
+int down_read(struct rw_semaphore *sem)
+	NO_THREAD_SAFETY_ANALYSIS
+{
+#if RWS_ERRORCHECK
+	mutex_lock(&sem->mtx);
+	return 0;
+#else
+	return perf_singlethreaded ? 0 : pthread_rwlock_rdlock(&sem->lock);
+#endif
+}
+
+int up_read(struct rw_semaphore *sem)
+	NO_THREAD_SAFETY_ANALYSIS
+{
+#if RWS_ERRORCHECK
+	mutex_unlock(&sem->mtx);
+	return 0;
+#else
+	return perf_singlethreaded ? 0 : pthread_rwlock_unlock(&sem->lock);
+#endif
+}
+
+int down_write(struct rw_semaphore *sem)
+	NO_THREAD_SAFETY_ANALYSIS
+{
+#if RWS_ERRORCHECK
+	mutex_lock(&sem->mtx);
+	return 0;
+#else
+	return perf_singlethreaded ? 0 : pthread_rwlock_wrlock(&sem->lock);
+#endif
+}
+
+int up_write(struct rw_semaphore *sem)
+	NO_THREAD_SAFETY_ANALYSIS
+{
+#if RWS_ERRORCHECK
+	mutex_unlock(&sem->mtx);
+	return 0;
+#else
+	return perf_singlethreaded ? 0 : pthread_rwlock_unlock(&sem->lock);
+#endif
+}