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From: Andres Rodriguez <andresx7-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
To: amd-gfx-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org
Cc: andresx7-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org
Subject: [PATCH 19/25] drm/amdgpu: add framework for HW specific priority settings v6
Date: Tue,  4 Apr 2017 18:05:45 -0400	[thread overview]
Message-ID: <20170404220551.8669-20-andresx7@gmail.com> (raw)
In-Reply-To: <20170404220551.8669-1-andresx7-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>

Add an initial framework for changing the HW priorities of rings. The
framework allows requesting priority changes for the lifetime of an
amdgpu_job. After the job completes the priority will decay to the next
lowest priority for which a request is still valid.

A new ring function set_priority() can now be populated to take care of
the HW specific programming sequence for priority changes.

v2: set priority before emitting IB, and take a ref on amdgpu_job
v3: use AMD_SCHED_PRIORITY_* instead of AMDGPU_CTX_PRIORITY_*
v4: plug amdgpu_ring_restore_priority_cb into amdgpu_job_free_cb
v5: use atomic for tracking job priorities instead of last_job
v6: rename amdgpu_ring_priority_[get/put]() and align parameters

Signed-off-by: Andres Rodriguez <andresx7@gmail.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_ctx.c       |  4 +-
 drivers/gpu/drm/amd/amdgpu/amdgpu_job.c       |  7 +++
 drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c      | 78 ++++++++++++++++++++++++++-
 drivers/gpu/drm/amd/amdgpu/amdgpu_ring.h      | 15 ++++++
 drivers/gpu/drm/amd/scheduler/gpu_scheduler.h |  7 +++
 5 files changed, 108 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ctx.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ctx.c
index 9edcf7f..56a2d27 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ctx.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ctx.c
@@ -25,21 +25,21 @@
 #include <drm/drmP.h>
 #include "amdgpu.h"
 
 static int amdgpu_ctx_init(struct amdgpu_device *adev,
 			   enum amd_sched_priority priority,
 			   struct amdgpu_ctx *ctx)
 {
 	unsigned i, j;
 	int r;
 
-	if (priority < 0 || priority >= AMD_SCHED_MAX_PRIORITY)
+	if (priority < 0 || priority >= AMD_SCHED_PRIORITY_MAX)
 		return -EINVAL;
 
 	if (priority == AMD_SCHED_PRIORITY_HIGH && !capable(CAP_SYS_ADMIN))
 		return -EACCES;
 
 	memset(ctx, 0, sizeof(*ctx));
 	ctx->adev = adev;
 	kref_init(&ctx->refcount);
 	spin_lock_init(&ctx->ring_lock);
 	ctx->fences = kcalloc(amdgpu_sched_jobs * AMDGPU_MAX_RINGS,
@@ -215,21 +215,21 @@ int amdgpu_ctx_ioctl(struct drm_device *dev, void *data,
 	enum amd_sched_priority priority;
 
 	union drm_amdgpu_ctx *args = data;
 	struct amdgpu_device *adev = dev->dev_private;
 	struct amdgpu_fpriv *fpriv = filp->driver_priv;
 
 	r = 0;
 	id = args->in.ctx_id;
 	priority = amdgpu_to_sched_priority(args->in.priority);
 
-	if (priority >= AMD_SCHED_MAX_PRIORITY)
+	if (priority >= AMD_SCHED_PRIORITY_MAX)
 		return -EINVAL;
 
 	switch (args->in.op) {
 	case AMDGPU_CTX_OP_ALLOC_CTX:
 		r = amdgpu_ctx_alloc(adev, fpriv, priority, &id);
 		args->out.alloc.ctx_id = id;
 		break;
 	case AMDGPU_CTX_OP_FREE_CTX:
 		r = amdgpu_ctx_free(fpriv, id);
 		break;
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c
index 86a1242..ac90dfc 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c
@@ -88,20 +88,21 @@ void amdgpu_job_free_resources(struct amdgpu_job *job)
 	f = job->base.s_fence ? &job->base.s_fence->finished : job->fence;
 
 	for (i = 0; i < job->num_ibs; ++i)
 		amdgpu_ib_free(job->adev, &job->ibs[i], f);
 }
 
 static void amdgpu_job_free_cb(struct amd_sched_job *s_job)
 {
 	struct amdgpu_job *job = container_of(s_job, struct amdgpu_job, base);
 
+	amdgpu_ring_priority_put(job->ring, amd_sched_get_job_priority(s_job));
 	dma_fence_put(job->fence);
 	amdgpu_sync_free(&job->sync);
 	kfree(job);
 }
 
 void amdgpu_job_free(struct amdgpu_job *job)
 {
 	amdgpu_job_free_resources(job);
 
 	dma_fence_put(job->fence);
@@ -162,28 +163,34 @@ static struct dma_fence *amdgpu_job_run(struct amd_sched_job *sched_job)
 	int r;
 
 	if (!sched_job) {
 		DRM_ERROR("job is null\n");
 		return NULL;
 	}
 	job = to_amdgpu_job(sched_job);
 
 	BUG_ON(amdgpu_sync_peek_fence(&job->sync, NULL));
 
+	r = amdgpu_ring_priority_get(job->ring,
+				     amd_sched_get_job_priority(&job->base));
+	if (r)
+		DRM_ERROR("Failed to set job priority (%d)\n", r);
+
 	trace_amdgpu_sched_run_job(job);
 	r = amdgpu_ib_schedule(job->ring, job->num_ibs, job->ibs, job, &fence);
 	if (r)
 		DRM_ERROR("Error scheduling IBs (%d)\n", r);
 
 	/* if gpu reset, hw fence will be replaced here */
 	dma_fence_put(job->fence);
 	job->fence = dma_fence_get(fence);
+
 	amdgpu_job_free_resources(job);
 	return fence;
 }
 
 const struct amd_sched_backend_ops amdgpu_sched_ops = {
 	.dependency = amdgpu_job_dependency,
 	.run_job = amdgpu_job_run,
 	.timedout_job = amdgpu_job_timedout,
 	.free_job = amdgpu_job_free_cb
 };
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c
index 2b452b0..b1af952 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c
@@ -193,35 +193,106 @@ void amdgpu_ring_commit(struct amdgpu_ring *ring)
  */
 void amdgpu_ring_undo(struct amdgpu_ring *ring)
 {
 	ring->wptr = ring->wptr_old;
 
 	if (ring->funcs->end_use)
 		ring->funcs->end_use(ring);
 }
 
 /**
+ * amdgpu_ring_priority_put - restore a ring's priority
+ *
+ * @ring: amdgpu_ring structure holding the information
+ * @priority: target priority
+ *
+ * Release a request for executing at @priority
+ */
+void amdgpu_ring_priority_put(struct amdgpu_ring *ring,
+			      enum amd_sched_priority priority)
+{
+	int i;
+
+	if (!ring->funcs->set_priority)
+		return;
+
+	if (atomic_dec_return(&ring->num_jobs[priority]) > 0)
+		return;
+
+	/* no need to restore if the job is already at the lowest priority */
+	if (priority == AMD_SCHED_PRIORITY_NORMAL)
+		return;
+
+	spin_lock(&ring->priority_lock);
+	/* something higher prio is executing, no need to decay */
+	if (ring->priority > priority)
+		goto out_unlock;
+
+	/* decay priority to the next level with a job available */
+	for (i = priority; i >= AMD_SCHED_PRIORITY_MIN; i--) {
+		if (i == AMD_SCHED_PRIORITY_NORMAL
+				|| atomic_read(&ring->num_jobs[i])) {
+			ring->priority = i;
+			ring->funcs->set_priority(ring, i);
+			break;
+		}
+	}
+
+out_unlock:
+	spin_unlock(&ring->priority_lock);
+}
+
+/**
+ * amdgpu_ring_priority_get - change the ring's priority
+ *
+ * @ring: amdgpu_ring structure holding the information
+ * @priority: target priority
+ *
+ * Request a ring's priority to be raised to @priority (refcounted).
+ * Returns 0 on success, error otherwise
+ */
+int amdgpu_ring_priority_get(struct amdgpu_ring *ring,
+			     enum amd_sched_priority priority)
+{
+	if (!ring->funcs->set_priority)
+		return 0;
+
+	atomic_inc(&ring->num_jobs[priority]);
+
+	spin_lock(&ring->priority_lock);
+	if (priority <= ring->priority)
+		goto out_unlock;
+
+	ring->priority = priority;
+	ring->funcs->set_priority(ring, priority);
+
+out_unlock:
+	spin_unlock(&ring->priority_lock);
+	return 0;
+}
+
+/**
  * amdgpu_ring_init - init driver ring struct.
  *
  * @adev: amdgpu_device pointer
  * @ring: amdgpu_ring structure holding ring information
  * @max_ndw: maximum number of dw for ring alloc
  * @nop: nop packet for this ring
  *
  * Initialize the driver information for the selected ring (all asics).
  * Returns 0 on success, error on failure.
  */
 int amdgpu_ring_init(struct amdgpu_device *adev, struct amdgpu_ring *ring,
 		     unsigned max_dw, struct amdgpu_irq_src *irq_src,
 		     unsigned irq_type)
 {
-	int r;
+	int r, i;
 
 	if (ring->adev == NULL) {
 		if (adev->num_rings >= AMDGPU_MAX_RINGS)
 			return -EINVAL;
 
 		ring->adev = adev;
 		ring->idx = adev->num_rings++;
 		adev->rings[ring->idx] = ring;
 		r = amdgpu_fence_driver_init_ring(ring,
 			amdgpu_sched_hw_submission);
@@ -293,23 +364,28 @@ int amdgpu_ring_init(struct amdgpu_device *adev, struct amdgpu_ring *ring,
 					    &ring->gpu_addr,
 					    (void **)&ring->ring);
 		if (r) {
 			dev_err(adev->dev, "(%d) ring create failed\n", r);
 			return r;
 		}
 		amdgpu_ring_clear_ring(ring);
 	}
 
 	ring->max_dw = max_dw;
+	ring->priority = AMD_SCHED_PRIORITY_NORMAL;
+	spin_lock_init(&ring->priority_lock);
 	INIT_LIST_HEAD(&ring->lru_list);
 	amdgpu_ring_lru_touch(adev, ring);
 
+	for (i = 0; i < AMD_SCHED_PRIORITY_MAX; ++i)
+		atomic_set(&ring->num_jobs[i], 0);
+
 	if (amdgpu_debugfs_ring_init(adev, ring)) {
 		DRM_ERROR("Failed to register debugfs file for rings !\n");
 	}
 	return 0;
 }
 
 /**
  * amdgpu_ring_fini - tear down the driver ring struct.
  *
  * @adev: amdgpu_device pointer
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.h
index 41ab767..e8ba708 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.h
@@ -17,20 +17,21 @@
  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  * OTHER DEALINGS IN THE SOFTWARE.
  *
  * Authors: Christian König
  */
 #ifndef __AMDGPU_RING_H__
 #define __AMDGPU_RING_H__
 
+#include <drm/amdgpu_drm.h>
 #include "gpu_scheduler.h"
 
 /* max number of rings */
 #define AMDGPU_MAX_RINGS		18
 #define AMDGPU_MAX_GFX_RINGS		1
 #define AMDGPU_MAX_COMPUTE_RINGS	8
 #define AMDGPU_MAX_VCE_RINGS		3
 #define AMDGPU_MAX_UVD_ENC_RINGS	2
 
 /* some special values for the owner field */
@@ -47,20 +48,21 @@ enum amdgpu_ring_type {
 	AMDGPU_RING_TYPE_UVD,
 	AMDGPU_RING_TYPE_VCE,
 	AMDGPU_RING_TYPE_KIQ,
 	AMDGPU_RING_TYPE_UVD_ENC
 };
 
 struct amdgpu_device;
 struct amdgpu_ring;
 struct amdgpu_ib;
 struct amdgpu_cs_parser;
+struct amdgpu_job;
 
 /*
  * Fences.
  */
 struct amdgpu_fence_driver {
 	uint64_t			gpu_addr;
 	volatile uint32_t		*cpu_addr;
 	/* sync_seq is protected by ring emission lock */
 	uint32_t			sync_seq;
 	atomic_t			last_seq;
@@ -134,20 +136,23 @@ struct amdgpu_ring_funcs {
 	void (*pad_ib)(struct amdgpu_ring *ring, struct amdgpu_ib *ib);
 	unsigned (*init_cond_exec)(struct amdgpu_ring *ring);
 	void (*patch_cond_exec)(struct amdgpu_ring *ring, unsigned offset);
 	/* note usage for clock and power gating */
 	void (*begin_use)(struct amdgpu_ring *ring);
 	void (*end_use)(struct amdgpu_ring *ring);
 	void (*emit_switch_buffer) (struct amdgpu_ring *ring);
 	void (*emit_cntxcntl) (struct amdgpu_ring *ring, uint32_t flags);
 	void (*emit_rreg)(struct amdgpu_ring *ring, uint32_t reg);
 	void (*emit_wreg)(struct amdgpu_ring *ring, uint32_t reg, uint32_t val);
+	/* priority functions */
+	void (*set_priority) (struct amdgpu_ring *ring,
+			      enum amd_sched_priority priority);
 };
 
 struct amdgpu_ring {
 	struct amdgpu_device		*adev;
 	const struct amdgpu_ring_funcs	*funcs;
 	struct amdgpu_fence_driver	fence_drv;
 	struct amd_gpu_scheduler	sched;
 	struct list_head		lru_list;
 
 	struct amdgpu_bo	*ring_obj;
@@ -172,32 +177,42 @@ struct amdgpu_ring {
 	uint64_t                eop_gpu_addr;
 	u32			doorbell_index;
 	bool			use_doorbell;
 	unsigned		wptr_offs;
 	unsigned		fence_offs;
 	uint64_t		current_ctx;
 	char			name[16];
 	unsigned		cond_exe_offs;
 	u64			cond_exe_gpu_addr;
 	volatile u32		*cond_exe_cpu_addr;
+
+	atomic_t		num_jobs[AMD_SCHED_PRIORITY_MAX];
+	spinlock_t		priority_lock;
+	/* protected by priority_lock */
+	int			priority;
+
 #if defined(CONFIG_DEBUG_FS)
 	struct dentry *ent;
 #endif
 };
 
 int amdgpu_ring_is_valid_index(struct amdgpu_device *adev,
 			       int hw_ip, int ring);
 int amdgpu_ring_alloc(struct amdgpu_ring *ring, unsigned ndw);
 void amdgpu_ring_insert_nop(struct amdgpu_ring *ring, uint32_t count);
 void amdgpu_ring_generic_pad_ib(struct amdgpu_ring *ring, struct amdgpu_ib *ib);
 void amdgpu_ring_commit(struct amdgpu_ring *ring);
 void amdgpu_ring_undo(struct amdgpu_ring *ring);
+int amdgpu_ring_priority_get(struct amdgpu_ring *ring,
+			     enum amd_sched_priority priority);
+void amdgpu_ring_priority_put(struct amdgpu_ring *ring,
+			      enum amd_sched_priority priority);
 int amdgpu_ring_init(struct amdgpu_device *adev, struct amdgpu_ring *ring,
 		     unsigned ring_size, struct amdgpu_irq_src *irq_src,
 		     unsigned irq_type);
 void amdgpu_ring_fini(struct amdgpu_ring *ring);
 int amdgpu_ring_lru_get(struct amdgpu_device *adev, int hw_ip,
 			struct amdgpu_ring **ring);
 void amdgpu_ring_lru_touch(struct amdgpu_device *adev, struct amdgpu_ring *ring);
 static inline void amdgpu_ring_clear_ring(struct amdgpu_ring *ring)
 {
 	int i = 0;
diff --git a/drivers/gpu/drm/amd/scheduler/gpu_scheduler.h b/drivers/gpu/drm/amd/scheduler/gpu_scheduler.h
index e266e1e..a33f6ec 100644
--- a/drivers/gpu/drm/amd/scheduler/gpu_scheduler.h
+++ b/drivers/gpu/drm/amd/scheduler/gpu_scheduler.h
@@ -152,11 +152,18 @@ void amd_sched_fence_slab_fini(void);
 struct amd_sched_fence *amd_sched_fence_create(
 	struct amd_sched_entity *s_entity, void *owner);
 void amd_sched_fence_scheduled(struct amd_sched_fence *fence);
 void amd_sched_fence_finished(struct amd_sched_fence *fence);
 int amd_sched_job_init(struct amd_sched_job *job,
 		       struct amd_gpu_scheduler *sched,
 		       struct amd_sched_entity *entity,
 		       void *owner);
 void amd_sched_hw_job_reset(struct amd_gpu_scheduler *sched);
 void amd_sched_job_recovery(struct amd_gpu_scheduler *sched);
+
+static inline enum amd_sched_priority
+amd_sched_get_job_priority(struct amd_sched_job *job)
+{
+	return (job->s_entity->rq - job->sched->sched_rq);
+}
+
 #endif
-- 
2.9.3

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  parent reply	other threads:[~2017-04-04 22:05 UTC|newest]

Thread overview: 30+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-04-04 22:05 [PATCH] Add support for high priority scheduling in amdgpu v7 Andres Rodriguez
     [not found] ` <20170404220551.8669-1-andresx7-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
2017-04-04 22:05   ` [PATCH 01/25] drm/amdgpu: refactor MQD/HQD initialization v2 Andres Rodriguez
2017-04-04 22:05   ` [PATCH 02/25] drm/amdgpu: doorbell registers need only be set once v2 Andres Rodriguez
2017-04-04 22:05   ` [PATCH 03/25] drm/amdgpu: detect timeout error when deactivating hqd Andres Rodriguez
2017-04-04 22:05   ` [PATCH 04/25] drm/amdgpu: remove duplicate definition of cik_mqd Andres Rodriguez
2017-04-04 22:05   ` [PATCH 05/25] drm/amdgpu: unify MQD programming sequence for kfd and amdgpu Andres Rodriguez
2017-04-04 22:05   ` [PATCH 06/25] drm/amdgpu: rename rdev to adev Andres Rodriguez
2017-04-04 22:05   ` [PATCH 07/25] drm/amdgpu: take ownership of per-pipe configuration v2 Andres Rodriguez
2017-04-04 22:05   ` [PATCH 08/25] drm/radeon: take ownership of pipe initialization Andres Rodriguez
2017-04-04 22:05   ` [PATCH 09/25] drm/amdgpu: allow split of queues with kfd at queue granularity v2 Andres Rodriguez
     [not found]     ` <20170404220551.8669-10-andresx7-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
2017-04-05  3:16       ` Alex Deucher
     [not found]         ` <CADnq5_PkNpqK-aKwPSFemE7oOXU0rJ38n9rtn_udWz8u+KHXjQ-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2017-04-05  4:09           ` Andres Rodriguez
2017-04-04 22:05   ` [PATCH 10/25] drm/amdgpu: teach amdgpu how to enable interrupts for any pipe v2 Andres Rodriguez
2017-04-04 22:05   ` [PATCH 11/25] drm/amdkfd: allow split HQD on per-queue granularity v4 Andres Rodriguez
2017-04-04 22:05   ` [PATCH 12/25] drm/amdgpu: remove duplicate magic constants from amdgpu_amdkfd_gfx*.c Andres Rodriguez
2017-04-04 22:05   ` [PATCH 13/25] drm/amdgpu: allocate queues horizontally across pipes Andres Rodriguez
2017-04-04 22:05   ` [PATCH 14/25] drm/amdgpu: remove hardcoded queue_mask in PACKET3_SET_RESOURCES Andres Rodriguez
2017-04-04 22:05   ` [PATCH 15/25] drm/amdgpu: new queue policy, take first 2 queues of each pipe Andres Rodriguez
2017-04-04 22:05   ` [PATCH 16/25] drm/amdgpu: untie user ring ids from kernel ring ids v4 Andres Rodriguez
     [not found]     ` <20170404220551.8669-17-andresx7-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
2017-04-05  3:06       ` Alex Deucher
     [not found]         ` <CADnq5_MA9npTkiX0gNsPDSyz7HoeHPSBpvcuYN3Vt2D7NtwPjw-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2017-04-05  3:12           ` Andres Rodriguez
2017-04-04 22:05   ` [PATCH 17/25] drm/amdgpu: implement lru amdgpu_queue_mgr policy for compute v4 Andres Rodriguez
2017-04-04 22:05   ` [PATCH 18/25] drm/amdgpu: add parameter to allocate high priority contexts v7 Andres Rodriguez
2017-04-04 22:05   ` Andres Rodriguez [this message]
2017-04-04 22:05   ` [PATCH 20/25] drm/amdgpu: convert srbm lock to a spinlock v2 Andres Rodriguez
2017-04-04 22:05   ` [PATCH 21/25] drm/amdgpu: implement ring set_priority for gfx_v8 compute v5 Andres Rodriguez
2017-04-04 22:05   ` [PATCH 22/25] drm/amdgpu: condense mqd programming sequence Andres Rodriguez
2017-04-04 22:05   ` [PATCH 23/25] drm/amdgpu: workaround tonga HW bug in HQD " Andres Rodriguez
2017-04-04 22:05   ` [PATCH 24/25] drm/amdgpu: guarantee bijective mapping of ring ids for LRU v3 Andres Rodriguez
2017-04-04 22:05   ` [PATCH 25/25] drm/amdgpu: use LRU mapping policy for SDMA engines Andres Rodriguez

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