Re: kernel - MPSAFE kern_mpipe.c

[Venkatesh Srinivas <me@xxxxxxxxxxxxxxxxxxx>]

A patch to convert to a per-pipe token; it hasn't exploded my vkernel yet... :D

diff --git a/sys/kern/kern_mpipe.c b/sys/kern/kern_mpipe.c

index 8a8559a..5b4a667 100644

--- a/sys/kern/kern_mpipe.c

+++ b/sys/kern/kern_mpipe.c

@@ -53,8 +53,6 @@

 

 static MALLOC_DEFINE(M_MPIPEARY, "MPipe Array", "Auxillary MPIPE structure");

 

-static struct lwkt_token mpipe_token = LWKT_TOKEN_MP_INITIALIZER(mpipe_token);

-

 /*

  * Initialize a malloc pipeline for the specified malloc type and allocation

  * size.  Create an array to cache up to nom_count buffers and preallocate

@@ -93,6 +91,8 @@ mpipe_init(malloc_pipe_t mpipe, malloc_type_t type, int bytes,

  ++mpipe->free_count;

  ++mpipe->total_count;

     }

+

+   lwkt_token_init(&mpipe->token, 1, "malloc pipeline token");

 }

 

 /*

@@ -121,6 +121,8 @@ mpipe_done(malloc_pipe_t mpipe)

  kfree(mpipe->array, M_MPIPEARY);

  mpipe->array = NULL;

     }

+

+    lwkt_token_uninit(&mpipe->token);

 }

 

 /*

@@ -135,7 +137,7 @@ mpipe_alloc_nowait(malloc_pipe_t mpipe)

     void *buf;

     int n;

 

-    lwkt_gettoken(&mpipe_token);

+    lwkt_gettoken(&mpipe->token);

     if ((n = mpipe->free_count) != 0) {

  /*

  * Use a free entry if it exists.

@@ -157,7 +159,7 @@ mpipe_alloc_nowait(malloc_pipe_t mpipe)

  if (buf)

     ++mpipe->total_count;

     }

-    lwkt_reltoken(&mpipe_token);

+    lwkt_reltoken(&mpipe->token);

     return(buf);

 }

 

@@ -172,7 +174,7 @@ mpipe_alloc_waitok(malloc_pipe_t mpipe)

     int n;

     int mfailed;

 

-    lwkt_gettoken(&mpipe_token);

+    lwkt_gettoken(&mpipe->token);

     mfailed = 0;

     for (;;) {

  if ((n = mpipe->free_count) != 0) {

@@ -204,7 +206,7 @@ mpipe_alloc_waitok(malloc_pipe_t mpipe)

  }

  mfailed = 1;

     }

-    lwkt_reltoken(&mpipe_token);

+    lwkt_reltoken(&mpipe->token);

     return(buf);

 }

 

@@ -219,7 +221,7 @@ mpipe_free(malloc_pipe_t mpipe, void *buf)

     if (buf == NULL)

  return;

 

-    lwkt_gettoken(&mpipe_token);

+    lwkt_gettoken(&mpipe->token);

     if ((n = mpipe->free_count) < mpipe->ary_count) {

  /*

  * Free slot available in free array (LIFO)

@@ -228,7 +230,7 @@ mpipe_free(malloc_pipe_t mpipe, void *buf)

  ++mpipe->free_count;

  if ((mpipe->mpflags & (MPF_CACHEDATA|MPF_NOZERO)) == 0) 

     bzero(buf, mpipe->bytes);

- lwkt_reltoken(&mpipe_token);

+ lwkt_reltoken(&mpipe->token);

 

  /*

  * Wakeup anyone blocked in mpipe_alloc_*().

@@ -245,7 +247,7 @@ mpipe_free(malloc_pipe_t mpipe, void *buf)

  KKASSERT(mpipe->total_count >= mpipe->free_count);

  if (mpipe->deconstruct)

     mpipe->deconstruct(mpipe, buf);

- lwkt_reltoken(&mpipe_token);

+ lwkt_reltoken(&mpipe->token);

  kfree(buf, mpipe->type);

     }

 }

diff --git a/sys/sys/mpipe.h b/sys/sys/mpipe.h

index 832b518..b54959e 100644

--- a/sys/sys/mpipe.h

+++ b/sys/sys/mpipe.h

@@ -83,6 +83,7 @@ struct malloc_pipe {

     int total_count; /* total outstanding allocations incl free */

     int ary_count; /* guarenteed allocation count */

     int max_count; /* maximum count (M_NOWAIT used beyond nom) */

+    lwkt_token token;

     void **array; /* array[ary_count] */

     void (*deconstruct)(struct malloc_pipe *, void *buf);

 };

-- vs