dtrace: SDT cleanup and bring in line with kernel

This commit performs some cleanup on the SDT provider, removing some
housekeeping tasks that are no longer needed (such as the need for an
arch-specific sdt_provide_module_arch() function).

This commit also contains a fix for the loop used in enabling and
disabling probes.  It was failing to ensure that the enable/disable
function was being called with the correct SDT probe.

Signed-off-by: Kris Van Hees <kris.van.hees@oracle.com>

diff --git a/dtrace/include/sparc64/dtrace/sdt_arch.h b/dtrace/include/sparc64/dtrace/sdt_arch.h
index c21ef6126fe938f78933c9e93ef661baa68fef8f..096b9ae944b70e38d0a776d3741aeef14610df74 100644 (file)
--- a/dtrace/include/sparc64/dtrace/sdt_arch.h
+++ b/dtrace/include/sparc64/dtrace/sdt_arch.h
@@ -32,7 +32,6 @@
  * Use is subject to license terms.
  */
 
-
 #define SDT_AFRAMES    1
 
 #endif /* _SPARC64_SDT_ARCH_H */

diff --git a/dtrace/include/x86_64/dtrace/sdt_arch.h b/dtrace/include/x86_64/dtrace/sdt_arch.h
index 0179400a2e3b2bcc616e1cae8a09a0ac4b368bbf..a24ec3c7e3e52746f592feb9dee878aaa8d3f4da 100644 (file)
--- a/dtrace/include/x86_64/dtrace/sdt_arch.h
+++ b/dtrace/include/x86_64/dtrace/sdt_arch.h
@@ -32,7 +32,6 @@
  * Use is subject to license terms.
  */
 
-
 #define SDT_AFRAMES    4
 
 #endif /* _X86_64_SDT_ARCH_H */

diff --git a/dtrace/sdt_dev.c b/dtrace/sdt_dev.c
index 4b29b66d2ed178672796afea22331eb696cfcc33..a672fb57561a28d7ec737f4fd4b1ca5891442d19 100644 (file)
--- a/dtrace/sdt_dev.c
+++ b/dtrace/sdt_dev.c
@@ -288,9 +288,6 @@ void sdt_provide_module(void *arg, struct module *mp)
                        return;
        }
 
-       if (!sdt_provide_module_arch(arg, mp))
-               return;
-
        for (idx = 0, sdpd = mp->sdt_probes; idx < mp->sdt_probec;
             idx++, sdpd++) {
                char                    *name = sdpd->sdpd_name, *nname;
@@ -379,6 +376,7 @@ void sdt_provide_module(void *arg, struct module *mp)
 int _sdt_enable(void *arg, dtrace_id_t id, void *parg)
 {
        sdt_probe_t     *sdp = parg;
+       sdt_probe_t     *curr;
 
        /*
         * Ensure that we have a reference to the module.
@@ -391,14 +389,12 @@ int _sdt_enable(void *arg, dtrace_id_t id, void *parg)
         * reference we took above, because we only need one to prevent the
         * module from being unloaded.
         */
-       PDATA(sdp->sdp_module)->sdt_enabled++;
-       if (PDATA(sdp->sdp_module)->sdt_enabled > 1)
+       PDATA(sdp->sdp_module)->enabled_cnt++;
+       if (PDATA(sdp->sdp_module)->enabled_cnt > 1)
                module_put(sdp->sdp_module);
 
-       while (sdp != NULL) {
-               sdt_enable_arch(sdp, id, arg);
-               sdp = sdp->sdp_next;
-       }
+       for (curr = sdp; curr != NULL; curr = curr->sdp_next)
+               sdt_enable_arch(curr, id, arg);
 
        return 0;
 }
@@ -406,6 +402,10 @@ int _sdt_enable(void *arg, dtrace_id_t id, void *parg)
 void _sdt_disable(void *arg, dtrace_id_t id, void *parg)
 {
        sdt_probe_t     *sdp = parg;
+       sdt_probe_t     *curr;
+
+       for (curr = sdp; curr != NULL; curr = curr->sdp_next)
+               sdt_disable_arch(curr, id, arg);
 
        /*
         * If we are disabling a probe, we know it was enabled, and therefore
@@ -413,14 +413,9 @@ void _sdt_disable(void *arg, dtrace_id_t id, void *parg)
         * being unloaded.  If we disable the last probe on the module, we can
         * drop the reference.
         */
-       PDATA(sdp->sdp_module)->sdt_enabled--;
-       if (PDATA(sdp->sdp_module)->sdt_enabled == 0)
+       PDATA(sdp->sdp_module)->enabled_cnt--;
+       if (PDATA(sdp->sdp_module)->enabled_cnt == 0)
                module_put(sdp->sdp_module);
-
-       while (sdp != NULL) {
-               sdt_disable_arch(sdp, id, arg);
-               sdp = sdp->sdp_next;
-       }
 }
 
 void sdt_getargdesc(void *arg, dtrace_id_t id, void *parg,

diff --git a/dtrace/sdt_sparc64.c b/dtrace/sdt_sparc64.c
index 65bc8d07ca41c12a056919c843a5d72786be1c0e..1c744ba11bdc965d1412d4b2658b50ef3329aaa3 100644 (file)
--- a/dtrace/sdt_sparc64.c
+++ b/dtrace/sdt_sparc64.c
@@ -44,7 +44,7 @@
  *     mov     %i1, %o2
  *     mov     %i2, %o3
  *     mov     %i3, %o4
- *     call    <diff > 0xfff>
+ *     call    dtrace_probe
  *      mov    %i4, %o5
  *     ret
  *      restore
@@ -56,7 +56,7 @@
  *     mov     %i1, %o2
  *     mov     %i2, %o3
  *     mov     %i3, %o4
- *     call    <diff <= 0xfff>
+ *     call    dtrace_probe
  *      mov    %i4, %o5
  *     ret
  *      restore
@@ -64,8 +64,10 @@
  * For is-enabled probes, we just drop an "or %g0, 1, %o0"
  * directly into the delay slot.
  */
-#if SDT_TRAMP_SIZE < 11
-# error SDT_TRAMP_SIZE is less than the required 11 instructions.
+#ifndef SDT_TRAMP_SIZE
+# error The kernel must define SDT_TRAMP_SIZE!
+#elif SDT_TRAMP_SIZE < 11
+# error SDT_TRAMP_SIZE must be at least 11 instructions!
 #endif
 
 #define SA(x)                  ((long)ALIGN((x), 4))
@@ -194,12 +196,6 @@ void sdt_disable_arch(sdt_probe_t *sdp, dtrace_id_t id, void *arg)
 
 int sdt_dev_init_arch(void)
 {
-       /*
-        * Sanity check to ensure that the memory allocated by the kernel is
-        * sufficient for what PDATA needs.
-        */
-       ASSERT(sizeof(dtrace_module_t) < DTRACE_PDATA_SIZE);
-
        return 0;
 }
 

diff --git a/dtrace/sdt_x86_64.c b/dtrace/sdt_x86_64.c
index 69440d2ce2e86a54befe6bb00e703e5df2e07aba..b8f1ef440f2b0729bb1e8e82d7126da36fe527cc 100644 (file)
--- a/dtrace/sdt_x86_64.c
+++ b/dtrace/sdt_x86_64.c
@@ -29,6 +29,7 @@
 #include <linux/slab.h>
 #include <linux/uaccess.h>
 #include <linux/vmalloc.h>
+#include <asm/dtrace_util.h>
 
 #include "dtrace.h"
 #include "dtrace_dev.h"
@@ -53,7 +54,7 @@ static uint8_t sdt_invop(struct pt_regs *regs)
                                this_cpu_core->cpu_dtrace_regs = NULL;
                        }
 
-                       return ASM_CALL_SIZE;
+                       return DTRACE_INVOP_NOPS;
                }
        }
 
@@ -66,11 +67,6 @@ void sdt_provide_probe_arch(sdt_probe_t *sdp, struct module *mp, int idx)
        sdp->sdp_savedval = *sdp->sdp_patchpoint;
 }
 
-int sdt_provide_module_arch(void *arg, struct module *mp)
-{
-       return 1;
-}
-
 void sdt_enable_arch(sdt_probe_t *sdp, dtrace_id_t id, void *arg)
 {
        dtrace_invop_enable((uint8_t *)sdp->sdp_patchpoint);
@@ -120,12 +116,6 @@ uint64_t sdt_getarg(void *arg, dtrace_id_t id, void *parg, int argno,
 
 int sdt_dev_init_arch(void)
 {
-       /*
-        * Sanity check to ensure that the memory allocated by the kernel is
-        * sufficient for what PDATA needs.
-        */
-       ASSERT(sizeof(dtrace_module_t) < DTRACE_PDATA_SIZE);
-
        return dtrace_invop_add(sdt_invop);
 }